bipalium adventitium is a land planarian in the subfamily bipaliinae .

it has been accidentally introduced in the united states , where it is considered invasive .

bipalium adventitium

bipalium adventitium <EOT> tracking and predation on earthworms by the invasive terrestrial planarian bipalium adventitium ( tricladida , platyhelminthes ) .

tracking and predation on earthworms by the invasive terrestrial planarian bipalium adventitium ( tricladida , platyhelminthes ) . - pubmed - ncbi

maggie whitson marked " land planarian ( bipalium sp . ) " as trusted on the " bipalium " page .

bipalium adventitium est un prédateur ver plat dans la famille geoplanidae d ' asie . # animaux # etrange # bizarre | pinterest | animaux and animal

dindal , d . l . , 1970 . feeding behavior of a terrestrial turbellarian bipalium adventitium . am . midl . nat . 83 : 635–637 .

dindal , d . l . 1970 . feeding behavior of a terrestrial turbellarian bipalium adventitium . the american midland naturalist 83 ( 2 ) : 635 - 637 .

zaborski , e . 2002 . observations on feeding behavior by the terrestrial flatworm bipalium adventitium ( platyhelminthes : tricladida : terricola ) from illinois . am . midl . nat . 148 : 401 - 408 .

ducey , p . k . , and s . noce . 1998 . successful invasion of new york state by the terrestrial flatworm , bipalium adventitium . northeastern naturalist 5 ( 3 ) : 199 - 206 .

yasuko shirasawa & naoya makino ( 1991 ) . pharyngeal regeneration in the land planarian bipalium kewense

maggie whitson changed the thumbnail image of " land planarian ( bipalium sp . ) " .

elution times and ttx profiles of an authentic ttx standard ( top ) , bipalium adventitium ( middle ) , and b . adventitium co - injected with a ttx standard ( 0 . 0005 mg / ml ) . the presence of single peak in the flatworm and co - injected sample confirm that the ttx like toxin present in this species is authentic ttx .

citation : stokes an , ducey pk , neuman - lee l , hanifin ct , french ss , pfrender me , et al . ( 2014 ) confirmation and distribution of tetrodotoxin for the first time in terrestrial invertebrates : two terrestrial flatworm species ( bipalium adventitium and bipalium kewense ) . plos one 9 ( 6 ) : e100718 . urltoken

ducey , p . k . ; west , l . j . ; shaw , g . ; de lisle , j . ( 2005 ) . " reproductive ecology and evolution in the invasive terrestrial planarian bipalium adventitium across north america " .

fiore , c . ; tull , j . l . ; zehner , s . ; ducey , p . k . ( 2004 ) . " tracking and predation on earthworms by the invasive terrestrial planarian bipalium adventitium ( tricladida , platyhelminthes ) " .

eduard solà marked " image of bipaliinae " as hidden on the " bipalium kewense moseley , 1878 " page .

stokes , a . , ducey , p . , neuman - lee , l . , hanifin , c . , french , s . , pfrender , m . , brodie , e . , & brodie jr , e . ( 2014 ) . confirmation and distribution of tetrodotoxin for the first time in terrestrial invertebrates : two terrestrial flatworm species ( bipalium adventitium and bipalium kewense )

one of 3 bipalium adventitium i found in my backyard on staten island on the first day of spring in 2010 . it is an invasive species that eats earthworms ( which are also invasive ) . check out the link for a description of them . urltoken and urltoken

curtis , s . k . , r . r . cowden , j . d . moore , and j . l . robertson . 1983 . histochemical and ultrastructural features of the epidermis of land planarian bipalium adventitium . j . of morphology 175 : 171 - 194 .

eduard solà marked " image of bipaliinae " as untrusted on the " bipalium kewense moseley , 1878 " page . reasons to untrust : misidentified

stokes , a . n . ; ducey , p . k . ; neuman - lee , l . ; hanifin , c . t . ; french , s . s . ; pfrender , m . e . ; brodie , e . d . ; brodie jr . , e . d . ( 2014 ) . " confirmation and distribution of tetrodotoxin for the first time in terrestrial invertebrates : two terrestrial flatworm species ( bipalium adventitium and bipalium kewense ) " .

daly jj , farris he jr , & matthews hm ( 1976 ) . pseudoparasitism of dogs and cats by the land planarian , bipalium kewense .

ducey , p . k . ; west , l . j . ; shaw , g . ; de lisle , j . ( 2005 ) . " reproductive ecology and evolution in the invasive terrestrial planarian bipalium adventitium across north america " . pedobiologia 49 ( 4 ) : 367 . doi : 10 . 1016 / j . pedobi . 2005 . 04 . 002 .

bipalium kewense notice the distinctive hammer - like head by ajaykuyiloor ( own work ) [ cc - by - sa - 3 . 0 ] , via wikimedia commons

miyoshi , y . , 1955 . observations on the food habit of bipalium . collect . & breed . , tokyo 17 : 377 . ( in japanese ) .

fiore , c . ; tull , j . l . ; zehner , s . ; ducey , p . k . ( 2004 ) . " tracking and predation on earthworms by the invasive terrestrial planarian bipalium adventitium ( tricladida , platyhelminthes ) " . behavioural processes 67 ( 3 ) : 327–334 . doi : 10 . 1016 / j . beproc . 2004 . 06 . 001 . pmid 15518983 .

neck , r . w . , 1987 . a predatory terrestrial flatworm , bipalium kewense , in texas : feral populations and laboratory observations . texas j . sci . 39 : 267–271 .

ducey , p . k . ; messere , m . ; lapoint , k . ; noce , s . ( 1999 ) . " lumbricid prey and potential herpetofaunal predators of the invading terrestrial flatworm bipalium adventitium ( turbellaria : tricladida : terricola ) " . the american midland naturalist 141 ( 2 ) : 305 . doi : 10 . 1674 / 0003 - 0031 ( 1999 ) 141 [ 0305 : lpaphp ] 2 . 0 . co ; 2 .

both bipalium kewense and b . adventitium exhibited ttx ( fig . 1 , 2 , and 3 ) . total ttx did not differ between the two species ( df = 1 , p = 0 . 4712 ) . the mean amount of total ttx in each sample for b . adventitium and b . kewense was 40 . 10 ng / ml ttx ( sem = 14 . 218 , range = bdl–81 . 42 ng / ml ) and 62 . 03 ng / ml ttx ( sem = 5 . 13 , range = 50 . 25–82 . 71 ng / ml ) , respectively . likewise , relative to mass the two species did not differ with a mean of 4 . 64 ng / mg ttx ( sem = 3 . 26 , range = bdl–19 . 89 ng / mg ) for whole b . adventitium , and a mean of 3 . 72 ng / mg ttx ( sem = 1 . 22 , range = 0 . 73–8 . 27 ng / mg ) for whole b . kewense .

landsperger , w . j . , e . h . peters & m . d . dresden , 1981 . properties of a collagenolytic enzyme from bipalium kewense . biochim . biophys . acta , 661 : 213–220 .

filella - subira , e . ( 1983 ) . «nota sobre la presència de la planària terrestre bipalium kewense moseley , 1878 a catalunya» . butll . inst . cat . hist . nat . , 49 : 151

winsor , l . 1983 . a revision of the cosmopolitan land planarian bipalium kewense moseley , 1878 ( turbellaria : tricladida : terricola ) . zool . j . of the linnean soc . 79 : 61 - 100 .

- winsor , l . 1983 . a revision of the cosmopolitan land planarian bipalium kewense moseley , 1878 ( turbellaria : tricladida : terricola ) . zool . j . of the linnean soc . 79 : 61 - 100 .

chandler , c . m . , 1976 . field observations on a population of the land planarian , bipalium kewense ( turbellaria , tricladida ) in middle tennessee . j . tenn . acad . sci . 51 : 73–75 .

olewine , d . a . , 1972 . further observations in georgia on the land planarians , bipalium kewense and geoplana vaga ( turbellaria : tricladida : terricola ) . assoc . southeast . biol . bull . 19 : 88 .

choate , p . m . , and dunn , r . a . , 1988 . land planarians , bipalium kewense moseley and dolichoplana striata moseley ( tricladida : terricola ) , ifas document eeny - 049 . online : available urltoken

hammerhead slug , crossing a road near hilo , hawaii . by dick culbert from gibsons , b . c . , canada ( bipalium kewense , a hammerhead worm . ) [ cc - by - 2 . 0 ] , via wikimedia commons

- ducey , p . k . , j . cerqua , l - j west , and m . warner . 2006 . rare egg capsule production in the invasive terrestrial planarian bipalium kewense . southwest naturalist 51 ( 2 ) : 252 - 254 .

ducey , p . k . ; cerqua , j . ; west , l . j . ; warner , m . ( 2006 ) . eberle , mark e , ed . " rare egg capsule production in the invasive terrestrial planarian bipalium kewense " .

ducey , p . k . , m . mccormick , and e . davidson . 2007 . natural history observations on bipalium cf . vagum jones and sterrer , 2005 ( platyhelminthes : tricladida ) , a terrestrial broadhead planarian new to north america . southeastern naturalist .

ogren , r . e . & j . k . sheldon , 1991 . ecological observations on the land planarian bipalium pennsylvanicum ogren , with references to phenology , reproduction , growth rate and food niche . j . pa . acad . sci . 65 : 3–9 .

ogren , r . e . 1987 . description of a new three - lined planarian of the genus bipalium ( turbellaria : tricladida ) from pennsylvania , u . s . a . trans . am . microsc . soc . 106 ( 1 ) : 21 - 30 .

barnwell , g . m . , l . j . peacock & r . e . taylor , 1965 . feeding behavior of a land planarian , bipalium kewense . unpublished manuscript presented to the southern society for philosophy and psychology , atlanta , ga , april , 15–17 , 1965 ( 8 pages photocopy available ) .

reproduction bipalium kewense is hermaphroditic ( like all bipalium species ) and capable of both asexual and sexual reproduction . however , the latter has rarely been observed and apparently fragmentation is the preffered form of reproduction . this is done by chipping off about 1cm of the tail . the tip first attaches itself to something in the soil , and then the parent worm pulls away . the new worm can move immediately and develops a head within 10 days . as for sexual reproduction , they lay eggs in a bright red cocoon . after one day the cocoon turns black and the eggs hatch about 20 days later , depending on temperature and moisture conditions .

we confirmed the presence of ttx in these species using hplc analysis ( fig . 1 ) . we compared the peaks from b . adventitium to that of a 0 . 0005 mg / ml ttx standard , and the flatworm sample co - injected with the same ttx standard . the single peak in the flatworm and in the co - injected sample indicates that this toxin is ttx and that ttx itself is the primary enantiomer present in these species .

ducey , p . k . ; cerqua , j . ; west , l . j . ; warner , m . ( 2006 ) . eberle , mark e , ed . " rare egg capsule production in the invasive terrestrial planarian bipalium kewense " . the southwestern naturalist 51 ( 2 ) : 252 . doi : 10 . 1894 / 0038 - 4909 ( 2006 ) 51 [ 252 : recpit ] 2 . 0 . co ; 2 .

html public " - / / w3c / / dtd xhtml 1 . 0 transitional / / en " " urltoken "

your web browser is not enabled for javascript . some features of worldcat will not be available .

your list has reached the maximum number of items . please create a new list with a new name ; move some items to a new or existing list ; or delete some items .

note : citations are based on reference standards . however , formatting rules can vary widely between applications and fields of interest or study . the specific requirements or preferences of your reviewing publisher , classroom teacher , institution or organization should be applied .

the e - mail address ( es ) field is required . please enter recipient e - mail address ( es ) .

the e - mail address ( es ) you entered is ( are ) not in a valid format . please re - enter recipient e - mail address ( es ) .

i thought you might be interested in this item at urltoken title : plos one publisher : san francisco , ca : public library of science . isbn / issn : 1932 - 6203 oclc : 969745500

public library of science . ; national institutes of health ( u . s . ) . pubmed central .

please choose whether or not you want other users to be able to see on your profile that this library is a favorite of yours .

you may have already requested this item . please select ok if you would like to proceed with this request anyway .

# national institutes of health ( u . s . ) . pubmed central .

worldcat is the world ' s largest library catalog , helping you find library materials online . learn more ››

don ' t have an account ? you can easily create a free account .

discover a faster , simpler path to publishing in a high - quality journal . plos one promises fair , rigorous peer review , broad scope , and wide readership – a perfect fit for your research every time .

copyright : © 2014 stokes et al . this is an open - access article distributed under the terms of the creative commons attribution license , which permits unrestricted use , distribution , and reproduction in any medium , provided the original author and source are credited .

data availability : the authors confirm that all data underlying the findings are fully available without restriction . all relevant data are within the supporting information files .

funding : utah state university , suny cortland , nsf : deb - 0922251 to me pfrender , ed brodie , jr , and ed brodie iii . the funders had no role in study design , data collection and analysis , decision to publish , or preparation of the manuscript .

segments are denoted as h for head , ab for anterior body , and pb for posterior body .

segments are denoted as h for head , ab for anterior body , and pb for posterior body . letters above bars indicate significant differences between segments .

although , ttx is best known as a defensive compound in vertebrates , there are many invertebrate groups that have ttx including red calcareous algae , dinoflagellates , bacteria , horseshoe crabs , blue - ringed octopuses , and multiple species of gastropods [ 4 ] . notably , several groups of worms possess ttx including annelids and flatworms ( planocera species ) [ 4 ] , [ 18 ] . though this taxonomic distribution is wide , this study is the first known to document the presence of ttx in any terrestrial invertebrate species .

currently , we have little conclusive knowledge regarding production or acquisition of ttx in the tissues of organisms . in marine systems the common view is that bacterial species produce ttx , which is then sequestered in the tissues of other organisms that ingest the bacteria [ 24 ] . puffer fish often are the example of this hypothesis , as they have little to no ttx when not fed a ttx - bearing diet [ 25 ] . however , even in puffer fish it is unclear where exactly the ttx came from as the production of ttx by bacterial species is still questionable [ 26 ] , and this hypothesis has not held up well in regards to terrestrial species [ 14 ] , [ 22 ] . our findings provide a potential avenue for ttx to move up the food chain in terrestrial organisms .

we would like to thank brian rivest , michelle hamerslough , and dan hodgson for help collecting these flatworms in the field . susan durham at utah state university provided helpful insight with statistical analyses .

conceived and designed the experiments : ans pkd ssf mep edmund d . brodie iii edmund d . brodie jr . performed the experiments : ans lnl cth . analyzed the data : ans . contributed reagents / materials / analysis tools : pkd cth ssf mep edmund d . brodie iii edmund d . brodie jr . wrote the paper : ans . extensive review and editing of manuscript : ans pkd lnl cth ssf mep edmund d . brodie iii edmund d . brodie jr .

narahashi t , moore jw , scott wr ( 1964 ) tetrodotoxin blockage of sodium conductuance increase in lobster giant axons . j gen phys 47 : 965–974 .

narahashi t , moore jw , poston rn ( 1967 ) tetrodotoxin derivatives : chemical structure and blockage of nerve membrane conductance . science 156 : 976–979 .

miyazawa k , noguchi t ( 2001 ) distribution and origin of tetrodotoxin . j toxicol - toxin rev 20 : 11–33 .

( turbellaria : tricladida : terricola ) . am midl nat 141 : 305–314 .

( platyhelminthes : tricladida : terricola ) from illinois . am midl nat 148 : 40–408 .

ogren re ( 1995 ) predation behaviour of land planarians . hydrobiologia 305 : 105–111 .

stokes an , williams bl , french ss ( 2012 ) an improved competitive inhibition enzymatic immunoassay method for tetrodotoxin quantification . biol proced online 14 : 3 available :

hanifin ct , brodie ed iii , brodie ed jr ( 2002 ) tetrodotoxin levels of the rough - skin newt , taricha granulosa , increase in long - term captivity . toxicon 40 : 1149–1153 .

hanifin ct , brodie ed jr , brodie ed iii ( 2008 ) phenotypic mismatches reveal escape from arms - race coevolution . plos biol 6 : 471–482 .

by a novel predator and its relationship with tetrodotoxin toxicity . am midl nat 165 : 389–399 .

ritson - williams r , yotsu - yamashita m , paul vj ( 2005 ) ecological functions of tetrodotoxin in a deadly polyclad flatworm . pnas : 3176–3179 .

kao cy ( 1966 ) tetrodotoxin , saxitoxin , and their significance in the study of excitation phenomena . pharmacol rev 18 : 997–1049 .

fuhrman fa , fuhrman gj , dull dl , mosher hs ( 1969 ) toxins from eggs of fishes and amphibia . j agri food chem 17 : 417–424 .

) produce tetrodotoxin laden eggs after long term captivity . toxicon 60 : 1057–1062 .

williams bl ( 2010 ) behavioral and chemical ecology of marine organisms with respect to tetrodotoxin . mar drugs 8 : 381–398 .

shimizu c , matssui t , sato h , yamamori k ( 1982 ) artificially reared puffers are not poisonous . mar sci mon 16 : 560 .

matsumura k ( 1995 ) reexamination of tetrodotoxin production by bacteria . app environ microbiol 61 : 3468–3470 .

do these subject areas make sense for this article ? click the target next to the incorrect subject area and let us know . thanks for your help !

scientists aim to describe a single ' tree of life ' that reflects the evolutionary relationships of living things . however , evolutionary relationships are a matter of ongoing discovery , and there are different opinions about how living things should be grouped and named . eol reflects these differences by supporting several different scientific ' classifications ' . some species have been named more than once . such duplicates are listed under synonyms . eol also provides support for common names which may vary across regions as well as languages .

eol content is automatically assembled from many different content providers . as a result , from time to time you may find pages on eol that are confusing .

to request an improvement , please leave a comment on the page . thank you !

pasedena , california , usa collection date : 1943 or earlier kind : default type comments : from a garden . campus , university of california berkeley , california , usa collection date : 1943 or earlier kind : default type comments : under boards . ursinus college , collegeville , montgomery county , pennsylvania , usa collection date : 1987 or earlier comments : on the campus and environs of ursinus college . on the campus and adjacent gardens

for the second time on the property , yesterday . i was checking amphibian cover boards and observed two individuals in what looked as if they were copulating . i collected the specimens and ran back to the office to confirm my identification . my colleague jeff greenwood , wmcc education director , ran an errand on the property shortly afterwards and found another individual . this brought us up to 3 specimens in one day ( april 26 , 2012 ) and we weren ' t even focusing a search for them !

blue - spotted x jefferson salamander is a state endangered species in ct that inhabits white memorial and eats earthworms .

is an introduced earthworm from asia and it is one of the few dirty words among forest ecologists ( please pardon the pun ) .

to peter ducey . since these species ( earthworms and flatworms ) have been introduced to north america from the horticultural industry , it is best to use native species in your garden raised by local growers using local stock for their plants , soils , and amendments . if you use worms as bait for fishing , throw any remaining worms into the garbage not your garden ! and finally , learn as much as you can about this topic ( soil , earthworms , invasive species , forest ecosystems , etc . ) on your own because soil is one of our vital natural resources that we all need , so take care of it .

location : the white memorial conservation center , inc . , 80 whitehall rd , litchfield , ct 06759 , usa

warning : the ncbi web site requires javascript to function . more . . .

department of biological sciences , state university of new york college at cortland , cortland , ny 13045 , usa .

this is an open access article distributed under the terms of the creative commons attribution license , which permits unrestricted use , distribution , reproduction and adaptation in any medium and for any purpose provided that it is properly attributed . for attribution , the original author ( s ) , title , publication source ( peerj ) and either doi or url of the article must be cited .

most animal invasive species detected in europe are terrestrial invertebrates ( roques et al . , 2009 ) . invading edaphic organisms can have dramatic effects on the environment , due to the direct effects on native soil organisms , and through their interactions with the environment aboveground . however , overall , their impact in human health and economy is greater than their ecological impact ( vilà et al . , 2010 ) . among these organisms , land planarians are becoming an important and diversified group of introduced species in europe .

) ; however , most species are found in the southern hemisphere . bipaliinae (

) are the subfamilies with the most northerly distribution , including europe . terrestrial planarians are the only free - living platyhelminthes that do not live in an aquatic habitat . however , they have not developed the capacity to prevent water loss and are thus strongly dependent on environmental moisture levels (

) . they seem to withstand this limitation through behavioral strategies such as hiding in damp refuges during the day and becoming active during the night . due to these characteristics , these animals are considered to have a low capacity to disperse . in fact , in their areas of origin , although a few species are well - adapted to open and human - transformed lands (

( a ) subfamily bipaliinae . ( b ) subfamily geoplaninae . information from urltoken .

( a ) subfamily microplaninae . ( b ) subfamily rhynchodeminae . information from urltoken .

after receiving multiple reports from non - scientists on the presence of “large and colored” terrestrial flatworms in several localities in the ip , and given their observed locations , particularly in private gardens , we decided to analyze their presence in garden centers and plant nurseries .

the aims of this work were to : ( 1 ) estimate the number of terrestrial flatworm species introduced in the ip , and find their region of origin ; ( 2 ) check whether plant nurseries and garden centers are acting as entrance gates and reservoirs ; ( 3 ) estimate the invasive potential of some introduced species by considering their diet and by using species distribution modeling ( sdm ) ; ( 4 ) propose measures to prevent their becoming invasive and to prevent further introductions and spread .

) : ( 1 ) gardens , ( 2 ) nurseries and plantations , ( 3 ) semi natural areas , and ( 4 ) from other countries ( either the original area of distribution or other invaded areas ) . specimens from sources 1 and 2 were either sent by people who knew our work through the information in social networks , or sampled by us ( all the localities reported by non - scientist collaborators correspond to gardens ) . specimens from source 3 were sampled by us . specimens from source 4 were sent by colleagues , specialists of the group , to whom we requested material for comparison with the iberian populations .

to each new sequence a three digit numeric code was assigned . sequences from the genbank database do not have specimen code numbers , only when there are more specimens from the same species in the same locality was a specimen code assigned ( three letters + one number ) . loc codes are as described in

. collector : db , dani boix ; em , eduardo mateos ; hj , hugh jones ; ka , miquel arnedo ; ll , laia leria ; lw , l winsor ; ma , marta álvarez - presas ; sg , s graham ; mv , miquel vila .

japan / baguñà et al . , 2001 – álvarez - presas , baguñà & riutort , 2008

leignston ( usa ) / baguñà et al . , 2001 – álvarez - presas , baguñà & riutort , 2008

ponta delgada , illa são miguel ( açores , portugal ) / db n37 . 745196 w25 . 667408 *

vall d’en bas ( girona , spain ) / mateos et al . , 2009

australia / baguñà et al . 2001– álvarez - presas , baguñà & riutort , 2008

malborough ( australia ) / baguñà et al . 2001– álvarez - presas , baguñà & riutort , 2008

menorca ( balearic islands , spain ) / ( breugelmans et al . , 2012 )

garden , adelaide ( australia ) / sg s34 . 988611 e138 . 599722 *

garden in townsville ( palmetum , australia ) / lw s19 . 260277 e146 . 822222 *

nursery in liverpool ( uk ) / hj n53 . 3525 w2 . 902777 *

saint pée sur nivelle ( france ) / ma n43 . 34235 w1 . 52650 *

townsville ( australia ) / baguñà et al . , 2001 - álvarez - presas , baguñà & riutort , 2008

luarca , asturias ( spain ) / ll 43°32′30 . 81″n6 °32′7 . 42″o *

canyamars ( barcelona , spain ) / em n41 . 598317 e2 . 44302 *

montjuïc ( barcelona , spain ) / vila - farré et al . , 2008 *

benamargosa ( málaga , spain ) / vila - farré et al . , 2011 *

sueiro , asturias ( spain ) / ll n43 . 527130 w6 . 877329 *

int . park la amistad , pila ( panamá ) / ka n8 . 524944 w82 . 618777 *

são paulo ( brazil ) / álvarez - presas et al . , 2011 - carbayo et al . , 2013

, loc - code p ) . in all three places recent habitat restoration activities have been performed , including the transplantation of autochthonous plant species from commercial nurseries .

amateur collaborators photographed the animals alive and fixed them in absolute ethanol . specimens we collected were also photographed and external morphological characters recorded . subsequently , animals were subjected to two different procedures to proceed to the species identification : ( 1 ) specimens for molecular analyses were fixed in 100 % ethanol and ( 2 ) specimens for histological studies were killed with boiling water , fixed with 10 % formalin for 24 h , and then preserved in 70 % ethanol .

preserved specimens were examined under a stereo microscope and notes of their dimensions , appearance , color ( though this is affected by preservation ) , eyes , any stripes or pattern , the position of the pharyngeal aperture ( mouth ) and gonopore , if present , were taken . specimens with no visible gonopore were considered to be immature . it was possible to identify some specimens , even immature ones , to species level without further examination . for unrecognized specimens , or where identity was uncertain and required confirmation , a mature specimen ( evidenced by an open gonopore ) was selected and divided into various portions , being embedded in wax . the copulatory apparatus ( gonopore ) and a small anterior region were sagittally and transversely sectioned at 10 or 15 µm , respectively , stained in harris’ haematoxylin and eosin and mounted in canada balsam .

a small piece of tissue fixed in absolute alcohol was digested with wizard genomic dna purification lysis buffer ( promega , madison , wi , usa ) and proteinase k overnight at 37 °c , following manufacturer’s instructions . the rest of the tissue is kept as voucher in the genetics department ( universitat de barcelona ) .

pcr products of the 28s gene for some individuals , that yielded double bands in the direct sequences , were cloned using htp topo ta cloning kit for sequencing ( invitrogen ) in order to be sure that only one type of sequence was recovered ( since the existence of a duplication of the ribosomal cluster is known in terrestrial planarians , carranza et al . , 1996 ) . the sequences of the clones showed that these bands corresponded to polymorphisms of one of the types . seqman ( v . 4 . 2 . 2 , gene codes ) was used to revise the chromatograms and obtain the definitive sequences .

based on the external appearance of the flatworms we initially grouped the specimens into nine morphotypes . we classified four of them at the species level due to their characteristic shapes or other external features , and the other five at genus or tribe level .

) has been identified by the characteristic shape of the anterior end and the pattern of stripes along the dorsal and ventral body surfaces . one specimen preserved in 70 % ethanol from bordils locality ( loc code v in

( a ) dorsal view . ( b ) ventral view of median part . ( c ) dorsal view of posterior end . ( d ) dorsal view of anterior end . scale bar 5 mm .

) . this specimen is deposited in the tissue collection of the genetics department ( universitat de barcelona ) .

dorsal view with partial ventral view in the center . the anterior end is not shown ( the specimen was damaged in this region ) . scale bar 5 mm .

phenotype , we have found two morphotypes basing on their color pattern . morphotype ca1 (

) presents a light brown dorsal region with a pale yellow middle - dorsal stripe , and a ventral light blue - greenish region . the histological study of one specimen from bordils locality ( loc code v in

( a ) dorsal view . ( b ) ventral view of median part . ( c ) lateral view of anterior end showing line of eyes . scale bar 5 mm .

( a ) dorsal view . ( b ) ventral view of median part and dorsal view of anterior end showing line of eyes . ( c ) lateral view of anterior end showing line of eyes . scale bar 5 mm .

) could also be identified by its characteristic external appearance . one specimen from bordils locality ( loc code v in

( a ) dorsal view . ( b ) ventral view of median part . ( c ) lateral view of anterior end showing the eye spot . scale bar 5 mm .

( a ) dorsal view . ( b ) ventral view of posterior end . ( c ) lateral view of anterior end showing line of eyes . scale bar 5 mm .

morph rs1 has a dark brown pigmented body with two black longitudinal stripes , and two large eyes situated a little distant from the anterior tip . one specimen from vall d’en bas locality ( loc code p in

( a ) dorsal view , scale bar 5 mm . ( b ) lateral view of anterior region , scale bar 2 . 5 mm .

a morphotype externally ascribable to the tribe rhynchodemini was found in benamargosa locality ( loc - code g ) , but its morphological features did not allow assigning it to any genus . rhynchodemini morph ri1 presents a dark brown pigmented body with one dorsal black line ( no image available ) .

) have a characteristic leaf - shaped , broad , flattened body . externally , they are very similar to

from brazil ( f carbayo , pers . comm . , 2013 ) . one specimen from bordils locality ( loc code v in

) . ( c ) ventral view . ( d ) lateral view of anterior end showing line of eyes . scale bar 5 mm .

we inferred ml trees to check the diagnosis of the introduced specimens and to determine their level of relatedness to the ones from the original areas of distribution . for this reason , the datasets included , when possible , sequences belonging to morphologically diagnosed specimens from the original area of distribution of the putative introduced species ( obtained for this study or coming from genbank ;

we obtained 28s sequences for 15 individuals . one or two sequences from each morphotype were aligned together with 19 genbank ingroup sequences and 3 outgroup sequences belonging to the

) . the best - fit model of sequence evolution for the 28s was gtr + g and for cox1 was gtr + i + g . we inferred a ml tree with partitions from a concatenated dataset including 37 individuals for which both 28s and cox1 sequences had been obtained (

maximum likelihood ( ml ) tree of the geoplanidae subfamilies and tribes ( bipaliinae , geoplaninae , caenoplanini , and rhynchodemini ) .

tree inferred from the concatenated dataset ( cox1 and 28s genes ) . three dugesia species as outgroups . values at nodes correspond to bootstrap ( > 75 ) for ml and posterior probability ( pp ) values from the bayesian analysis ( > 0 . 95 ) .

tree inferred from the cox1 gene . three microplana species as outgroups . values at nodes correspond to bootstrap ( > 75 ) and pp ( > 0 . 95 ) values .

tree inferred from the cox1 gene . one species of genres arthurdendyus , artioposthia , australoplana and caenopolana as outgroups . values at nodes correspond to bootstrap ( > 75 ) and pp ( > 0 . 95 ) values .

) . in the cox1 tree , specimens coming from the ip , united kingdom ( both introduced ) and brazil ( original area ) constitute a highly - supported monophyletic group . within this group , the introduced individuals are divided in two quite differentiated clades (

) , also distinctly separated from the brazilian individuals . all the uk individuals fall within the clade

tree inferred from the cox1 gene . two cratera species as outgroups . values at nodes correspond to bootstrap ( > 75 ) and pp ( > 0 . 95 ) values .

) includes a high number of introduced individuals and the broadest diversity of sequences . even

sequences , either coming from genbank , or from the individuals sent by our collaborator in australia , are found in very distinct genetic clades pointing to the existence of more than one species ( see discussion ) . for this reason , we use the name

s . l . to refer to all those specimens . in the concatenated tree , the representative of

. the divergence among these three lineages can be appreciated when compared to the other subfamilies present in the tree . in the cox1 tree (

again shows high levels of genetic diversity , evidenced by the long branches separating its subclades . most

s . l . from its original area ( australia ) and also from uk and menorca ( also introduced ) . this clade is sister to another group including

) ; however , the differentiation among these two clades is extremely high . the other two

morphotype ca1 individuals , coming from townsville ( australia ) , constitute a highly differentiated clade that also includes a genbank sequence identified only to the genus level and one of the introduced individuals . finally , there is a clade including only introduced animals , one of them identified as

and the rest as morphotype ca2 . the genetic differentiation between the two lineages within this clade is nonetheless extremely high .

tree inferred from the cox1 gene . one rhynchodemus species , one platydemus species , and two dolichoplana species as outgroups . values at nodes correspond to bootstrap ( > 75 ) and pp ( > 0 . 95 ) values .

sequences form a monophyletic clade in the cox1 tree , including three introduced animals in the ip and one coming from brazil . the individuals assigned to rhynchodemini morphotype ri1 collected in málaga ( spain , loc code g in

specimens analyzed constitute a monophyletic group with a low variability , the french representative being the more divergent . the genus

show the sampling localities of the animals analyzed in this study . in all the plant nurseries , only one species of terrestrial planarian was found (

, loc - code v ) . the rest of the localities also contained a single species , with the exception of treto ( a garden , loc - code u ) with two species , and the two “semi natural areas” situated in vall d’en bas ( loc - code p ) and in granollers ( loc - code m ) also with two species each .

s . l . in the ip presents mean values of auc beyond 0 . 9 ( 0 . 974 ) and significance for all tests of omission , which indicates good performance of the models . furthermore , predictions were significantly different from random because binomial omission test thresholds were significant (

< 0 . 01 ) in all 1 , 000 runs . a composite map showing the potential distribution models for

the color gradient indicates the predicted likelihood that the environmental conditions suitable for the species based on the maxent average output . letters indicate localities where

the results of the potential distribution of the species in the ip , based on data from its current distribution in their region of origin ( australia ) , show that the species can find extremely suitable areas for its survival and expansion is the northern region , where the appropriate temperature and humidity conditions occur .

, monophyletic in the trees , leads us to predict that it includes more than one species . in the cox1 tree (

) , at least three monophyletic groups seem to be clearly defined and probably represent different species . in fact ,

is philadelphia , pennsylvania , usa ( 1851 ) . this species has a wide distribution in the ip and two of the locations are plant nurseries , one in barcelona (

) , while the other localities can be considered natural habitats . in our molecular analysis there was no separation of specimens according to their locality type ( natural or artificial ) . two distinct clades of european

in the case of rhyncodemini ri1 , this species probably belongs to the genus dolichoplana ; however , we were only able to obtain three specimens and none of them were sexually mature .

( schultze & müller , 1857 ) due to their external appearance ; however , molecular data ( m riutort , unpublished data , 2014 ) showed that the european specimens did not constitute a monophyletic group with that species , indicating that they belonged to an unknown , still undescribed , geoplaninae . sampling performed in brazil since then has found another species (

sp . 6 ) , which is also externally very similar . molecular data show that it is closely related to the individuals found in europe ( m riutort , unpublished data , 2014 ) . as in the previous case , a morphological and molecular study should be undertaken to clearly delimit and describe the new species . the two clades found in our cox1 tree (

) , that may represent two different species , suggest that there have been two independent introductions into the ip from different native sites in brazil .

see winsor , johns & barker , 2004 for refs olewine , 1972 terrace & baker , 1994 mateos et al . , 2013 barnwell , 1978

s . l . , we performed a potential distribution study to check whether the area around its present introduced localities in the ip may be suitable for its expansion . the results show that the potential distribution of the species (

) indeed includes the countryside that was nearby to the localities of the ip where it is already present . the most suitable area is the northern ip . this is not surprising when we consider that in this northern region , the climatic conditions ( temperature and humidity ) are also more optimal for the presence of native land planarians (

) . thus , we show that by having suitable climatic databases , it is possible to model the potential distribution of introduced species , and thus predict their risk of becoming invasive . if we add to this information the knowledge of some biological features of the terrestrial planarian species , such as their prey preferences , we may be able to make an even more precise image of the sites where it is more likely for the species to become invasive and thus concentrate prevention efforts in those areas .

no reference has been made to the effect of these species on autochthonous populations of terrestrial planarians , probably because the knowledge of the autochthonous fauna is very scarce . in the ip we have already performed some studies on the autochthonous terrestrial planarian fauna and found that it is very diverse , including at least 15 species , of which some contain a great deal of genetic diversity ( mateos et al . , 2009 ; álvarez - presas et al . , 2012 ) . the potential arrival of some of these introduced species in natural habitats , where the autochthonous ones are localized ( as predicted by the potential distribution studies ) , would have very negative consequences . since exotic planarians are , in general , bigger in size , more voracious , have more aggressive behavior , and sometimes appear to have a generalist diet ( pers . obs . ) , they may be more resistant to extreme conditions than the native species .

this research was supported by the ministerio de ciencia e innovación of spain ( cgl2011 - 23466 ) . the funders had no role in study design , data collection and analysis , decision to publish , or preparation of the manuscript .

marta álvarez - presas , eduardo mateos and marta riutort conceived and designed the experiments , performed the experiments , analyzed the data , contributed reagents / materials / analysis tools , wrote the paper , prepared figures and / or tables , reviewed drafts of the paper .

àngels tudó performed the experiments , analyzed the data , wrote the paper , prepared figures and / or tables .

hugh jones performed the experiments , analyzed the data , contributed reagents / materials / analysis tools , wrote the paper , prepared figures and / or tables , reviewed drafts of the paper .

álvarez - presas m , baguñà j , riutort m . molecular phylogeny of land and freshwater planarians ( tricladida , platyhelminthes ) : from freshwater to land and back .

álvarez - presas m , carbayo f , rozas j , riutort m . land planarians ( platyhelminthes ) as a model organism for fine - scale phylogeographic studies : understanding patterns of biodiversity in the brazilian atlantic forest hotspot .

álvarez - presas m , mateos e , vila - farré m , sluys r , riutort m . evidence for the persistence of the land planarian species

( müller , 1774 ) ( platyhelminthes , tricladida ) in microrefugia during the last glacial maximum in the northern section of the iberian peninsula .

baguñà j , carranza s , paps j , ruiz - trillo i , riutort m . molecular taxonomy and phylogeny of tricladida . in : littlewood dtj , bray rd , editors .

baptista va , leal - zanchet am . land flatworm community structure in a subtropical deciduous forest in southern brazil .

boag b , yeates gw , johns pm . limitations to the distribution and spread of terrestrial flatworms with special reference to the new zealand flatworm (

boag b , neilson r . impact of new zealand flatworm on agricultura and wildlife in scotland . proceedings of crop protection in northern britain conference ; 2006 . pp . 51–56 .

boag b , neilson r , jones hd . quantifying the risk to biodiversity by alien terrestrial planarians .

breugelmans k , cardona jq , artois t , jordaens k , backeljau t . first report of the exotic blue land planarian ,

campbell je , gibson dj . the effect of seeds of exotic species transported via horse dung on vegetation along trail corridors .

cannon rjc , baker rha , taylor mc , moore jp . a review of the status of the new zealand flatworm in the uk .

carbayo f , leal - zanchet am , vieira em . terrestrial flatworm ( platyhelminthes : tricladida : terricola ) diversity versus man - induced disturbance in an ombrophilous forest in southern brazil .

carbayo f , álvarez - presas m , olivares ct , marques fpl , froehlich em , riutort m . molecular phylogeny of geoplaninae ( platyhelminthes ) challenges current classification : proposal of taxonomic actions .

carranza s , giribet g , ribera c , baguñà j , riutort m . evidence that two types of 18s rdna coexist in the genome of

carranza s , littlewood dtj , clough ka , ruiz - trillo i , baguñà j , riutort m . a robust molecular phylogeny of the tricladida ( platyhelminthes : seriata ) with a discussion on morphological synapomorphies .

darriba d , taboada gl , doallo r , posada d . jmodeltest 2 : more models , new heuristics and parallel computing .

defra 2005 . code of practice to prevent the spread of non - indigenous flatworms . available at urltoken ( accessed 28 march 2014 )

dehnen - schmutz k , holdenrieder o , jeger mj , pautasso m . structural change in the international horticultural industry : some implications for plant health .

dove 2012 . code of practice to prevent the spread of non - indigenous flatworms . dove associates 17 / 01 / 2012 .

drew j , anderson n , andow d . conundrums of a complex vector for invasive species control : a detailed examination of the horticultural industry .

ducey pk , noce s . successful invasion of new york state by the terrestrial flatworm ,

eppo 2000a . import requirements concerning arthurdendyus triangulatus . eppo standard pm 1 / 3 ( 1 )

eppo 2000b . nursery inspection , exclusion and treatment for arthurdendyus triangulatus . eppo standard pm 1 / 4 ( 1 )

faubel a . 2004 . fauna europaea : platyhelminthes , tricladida , terricola . fauna europaea version 1 . 1 . available at urltoken ( accessed 28 march 2014 )

fernández f , lago d , negrete l , brusa f , damborenea c , noreña c . 2013 . presencia de obama marmorata ( schultze & müller , 1857 ) sf geoplaninae en la península ibérica . primer registro de este género para europa . [ abstract no 6 ] . vi jornadas del departament de biodiversidad y biología evolutiva ( mncn - csic ) - 2013 : 19 . available at urltoken ( accessed 1 may 2014 )

boletim da faculdade de filosofia , ciências e letras da universidade de são paulo , série zoologia .

great britain non - native species secretariat 2013 . kontikia flatworms ( kontikia ventrolineata and andersoni ) . available at urltoken ( accessed 1 may 2014 )

hall ta . bioedit : a user - friendly biological sequence alignment editor and analysis program for windows 95 / 98 / nt .

hijmans rj , cameron se , parra jl , jones pg , jarvis a . very high resolution interpolated climate surfaces for global land areas .

jones hd . the african and european land planarian fauna , with an identification guide for field workers in europe .

jones hd , johns pm , winsor l . the proposed synonymy of parakontikia ventrolineata ( dendy , 1892 ) and kontikia mexicana ( hyman , 1939 ) : what is a penis papilla ?

jones hd , webster bl , littlewood dtj , mcdonald jc . molecular and morphological evidence for two new species of terrestrial planarians of the genus

justine jl , winsor l , gey d , gros p , thévenot j . the invasive new guinea flatworm

in france , the first record for europe : time for action is now .

katoh k , standley dm . mafft multiple sequence alignment software version 7 : improvements in performance and usability .

lázaro em , sluys r , pala m , stocchino ga , baguñà j , riutort m . molecular barcoding and phylogeography of sexual and asexual freshwater planarians of the genus

lilleskov e , callaham ma , pouyat r , smith je , castellano m , gonzalez g , lodge dj , arango r , green f . invasive soil organisms and their effects on belowground processes . in : dix me , britton k , editors .

washington dc : usda forest service , research and development gtr wo - 79 / 83 ; 2010 . pp . 67–83 .

mateos e , cabrera c , carranza s , riutort m . molecular analysis of the diversity of terrestrial planarians ( platyhelminthes , tricladida , continenticola ) in the iberian peninsula .

mateos e , giribet g , carranza s . terrestrial planarians ( platyhelminthes , tricladida , terricola ) from the iberian peninsula : first records of the family rhynchodemidae , with the description of a new

mateos e , tudó a , álvarez - presas m , riutort m . planàries terrestres exòtiques a la garrotxa .

mcdonald jc , jones hd . abundance , reproduction , and feeding of three species of british terrestrial planarians : observations over 4 years .

committee on the scientific basis for predicting the invasive potential of nonindigenous plants and plant pests in the united states , national research council . washington dc : the national academies press ; 2002 .

ogren re . the human factor in the spread of an exotic planarian in pennsylvania .

ogren re , kawakatsu m . american nearctic and neotropical land planarian ( tricladida : terricola ) faunas .

phillips sj , anderson rp , schapire re . maximum entropy modeling of species geographic distributions .

phillips sj , dudík m . modeling of species distributions with maxent : new extensions and a comprehensive evaluation .

richardson dm , pyšek p , rejmánek m , barbour mg , panetta fd , west cj . naturalization and invasion of alien plants : concepts and definitions .

ronquist f , teslenko m , van der mark p , ayres dl , darling a , höhna s , larget b , liu l , suchard ma , huelsenbeck jp . mrbayes 3 . 2 : efficient bayesian inference and model choice across a large model space .

roques a , rabitsch w , rasplus jy , lopez - vaamonde c , nentwig w , kenis m .

dordrecht : springer ; 2009 . alien terrestrial invertebrates of europe ; pp . 63–79 .

seerad 2000 . biological and ecological studies of the new zealand flatworm , arthurdendyus triangulatus : towards a comprehensive risk assessment for the uk . final report for the period 1st march 1997 to 31st march 2000 . central science laboratory ministry of agriculture , fisheries and food , sand hutton , york .

sluys r , kawakatsu m , riutort m , baguñà j . a new higher classification of planarian flatworms ( platyhelminthes , tricladida )

simberloff d , martin jl , genovesi p , maris v , wardle da , aronson j , courchamp f , galil b , garcía - berthou e , pascal m , pysek p , sousa r , tabacchi e , vilà m . impacts of biological invasions : what’s what and the way forward .

stamatakis a . raxml - vi - hpc : maximum likelihood - based phylogenetic analyses with thousands of taxa and mixed models .

sugiura s . hot water tolerance of soil animals : utility of hot water immersions for biological invasions of soil animals .

sunnucks p , blacket mj , taylor jm , sands cj , ciavaglia sa , garrick rc , tait nn , rowell dm , pavlova a . a tale of two flatties : different responses of two terrestrial flatworms to past environmental climatic fluctuations at tallaganda in montane southeastern australia .

vilà m , basnou c , pysek p , josefsson m , genovesi p , gollasch s , nentwig w , olenin s , roques a , roy d , hulme pe , daisie partners how well do we understand the impacts of alien species on ecosystem services ? a pan - european , cross - taxa assessment .


batodonoides ( often misspelled as batonoides ) is a genus of extinct shrew-like mammals , which includes a species that is possibly the smallest mammal to have ever lived .

species of batodonoides lived about 42 to 53 million years ago during the early to middle eocene epoch in north america .

the genus contains four species : the type species b. powayensis , the older b. vanhouteni , b. walshi and b. rileyi .

batodonoides

batodonoides <EOT> the smallest mammal alive today is the bumblebee bat , which is only slightly larger than batodonoides .

length : 2 . 5 cm ( 1 in ) weight : 1 . 3 g ( 0 . 05 oz ) time : 55 , 400 , 000 - 42 , 000 , 000 b . c . location : california and wyoming , united states species : batodonoides powayensis batodonoides vanhouteni

a shrew - like , insect - eating mammal , batodonoides appears to be the smallest mammal ever to walk the earth . the smaller and older species ,

while batodonoides is the smallest mammal ever , the largest animal - - mammal or otherwise - - is the blue whale , with a heart the size of a small car .

jonathan i . bloch , kenneth d . rose , philip d . gingerich ; new species of batodonoides ( lipotyphla , geolabididae ) from the early eocene of wyoming : smallest known mammal ? , journal of mammalogy , volume 79 , issue 3 , 21 august 1998 , pages 804–827 , urltoken

full reference : j . i . bloch , k . d . rose , and p . d . gingerich . 1998 . new species of batodonoides ( lipotyphla , geolabididae ) from the early eocene of wyoming : smallest known mammal ? . journal of mammalogy 79 ( 3 ) : 804 - 827

53 million years old , and it may be the smallest mammal that has ever lived . batodonoides vanhouteni was a shrew - like mammal that scientific illustrator jen christiansen has deftly described in this illustration . in addition to being an illustrator , christiansen is also scientific american ' s art editor of information graphics .

the smallest mammal that ever lived could be sitting right on your shoulder and you would hardly know it . batodonoides vanhouteni , which lived about 50 million years ago in what is now wyoming , was so small that it could climb up a pencil - - and it weighed as little as a dollar bill .

paleontologist jonathan bloch found a tiny fossil jaw of batodonoides . " under a microscope , i realized i was looking at the smallest mammal teeth i had ever seen , " bloch said . several slightly larger species of these mini - mammals lived between 55 and 42 million years ago , but they are now all extinct .

composing an illustration with only a few , spare elements can be incredibly difficult , moreso if the aim is to inform instead of to simply look pleasing . there is a remarkable economy of information in this piece : we can see just how tiny the batodonoides vanhouteni is next to a modern etruscan shrew . the familiar wooden ruler prompts us to what ' s important about the relationship between the wee mammals .

with mammals as large as the blue whale ( balaenoptera musculus ) and the african elephant ( loxodonta africana ) , it may be hard to imagine that the world’s smallest mammal is only about the size of your fingernail . this miniature mammal , batodonoides vanhouteni , was an ancient ancestor of the modern day shrew and weighed about 1 . 3 grams— the equivalent mass of a single dollar bill ! this species of tiny rodents is said to have inhabited the underbrush of prehistoric forests .

the museum is open daily from 10 am to 5 : 45 pm except on thanksgiving and christmas .

can ' t find a community you love ? create your own and start something epic .

html public " - / / w3c / / dtd xhtml 1 . 0 transitional / / en " " urltoken "

, had teeth roughly a millimeter ( one - tenth of an inch ) in length and is thought to have weighed 1 . 3 grams ( 0 . 05 oz ) , the weight of a dollar bill and slightly lighter than the smallest mammal in our time , the etruscan shrew .

html public " - / / w3c / / dtd html 4 . 01 transitional / / en "

javascript is required to use this web site . please turn it on before proceeding .

full reference : m . j . novacek . 1976 . early tertiary vertebrate faunas , vieja group , trans - pecos texas : insectivora . pearce - sellards series 23

average measurements ( in mm ) : m1 1 . 11 x 0 . 64

type specimen : um 101991 , a maxilla . its type locality is sc - 303 , which is in a wasatchian terrestrial horizon in the willwood formation of wyoming .

average measurements ( in mm ) : m1 0 . 750 x 0 . 540

all scientific illustrators bring different skill sets into their work . looking at this , i can ' t help but think that the simplicity and pared down elements common to the best infographics was informing christiansen ' s compositional choices

you can see more of jen christiansen ' s work - both her own illustrations and infographics she has guided and edited - at her site + portfolio .

for the third year running , we are turning september into a month - long celebration of science artists by delivering new sciart to invade your eyeballs . the sciart blitz ! can’t get enough ? check out what was previously featured on this day :

the views expressed are those of the author ( s ) and are not necessarily those of scientific american .

glendon mellow is a fine artist , illustrator and tattoo designer working in oil and digital media based in toronto , canada . he tweets @ flyingtrilobite and is on instagram . you can see glendon ' s work - in - progress at the flying trilobite blog and portfolio at urltoken .

discover world - changing science . explore our digital archive back to 1845 , including articles by more than 150 nobel prize winners .

scientific american is part of springer nature , which owns or has commercial relations with thousands of scientific publications ( many of them can be found at urltoken ) . scientific american maintains a strict policy of editorial independence in reporting developments in science to our readers .

encyclo . co . uk , online since 2007 , is a search engine for english meanings and definitions . the website aims to publish all wordlists , big and small , on the internet , making it much easier to find the word you need . follow us on facebook

popular : trivia , history , america , television , tv , usa , geography , cities , . . . more

note : count is of distinct taxa , meaning named species plus genera with no identified species at this locality .

note : assorted invalid combinations involving the same synonymous species name are counted separately .

note : many of these species are small marsupials , rodents , or insectivorans .

notes : regression equations perform poorly for very large species , and some of these estimates are likely to be too high . proboscidean sizes are estimated from m2 , not m1 .

note : authors receive half - credit for co - authored actions . taxonomic contributions of lander and frick each appeared mostly in just one publication .

notes : authors receive half - credit for co - authored lists . most of kihm ' s lists are from an unpublished ph . d . thesis . most of skinner ' s " lists " are locality descriptions with identifications provided by other authors .

note : only senior authors are counted . nineteenth - century authors ( including matthew ) are excluded .

/ bloch , jonathan i . ; rose , kenneth d . ; gingerich , philip d .

bloch , jonathan i . ; rose , kenneth d . ; gingerich , philip d . /

author = " bloch , { jonathan i . } and rose , { kenneth d . } and gingerich , { philip d . } " ,

powered by pure , scopus & elsevier fingerprint engine™ © 2018 elsevier b . v .

cookies are used by this site . to decline or learn more , visit our cookies page

we use cookies to enhance your experience on our website . by continuing to use our website , you are agreeing to our use of cookies . you can change your cookie settings at any time .

oxford university press is a department of the university of oxford . it furthers the university ' s objective of excellence in research , scholarship , and education by publishing worldwide

for full access to this pdf , sign in to an existing account , or purchase an annual subscription .

see it ( and compare it to the largest land mammal . . . ) when you visit " extreme mammals " at the field museum !

at chicago ' s field museum . ( it closes january 6th , so if you ' re interested , go now ! ) one of the very first thing that you come across is a display of both the largest land animal ever (

is that very creature - - the smallest mammal ever discovered . this itty bitty , tiny little shrew - like critter lived during the eocene between 53 and 42 million years ago . it was so small that is weighed less than a dollar bill and could comfortably sit on the top of a pencil !

there are three species within the genus , the first of which was discovered back in 1976 . all have been found in the western united states . the smallest of the three ,

of course , we still have tiny mammals today . the smallest still alive , the

text and design by lauren robb . awesome inc . theme . theme images by airyelf . powered by blogger .

prettylitter is lightweight , odorless , long - lasting and best yet , keeps tabs on your cat’s health .

the feedback you provide will help us show you more relevant content in the future .

there’s one contender not noted in the other answers so far : hadrocodium wui , a species from the early jurassic known from a skull . it is estimated at 32mm in length and 2g in mass .

that estimate could be wrong , since none of the postcranial body is known .

it is probably not quite a mammal , but a very , very close relative of mammals .

, garden expert , and gardengail1 on yahoo answers , i ' ve worked at the home depot for 21 years , 35 years garde . . .

smallest animals in the world ! 5 weird animal facts - ep . 14 : animalbytestv

animal records ( biggest , longest , tallest , fastest . . ) ever !