Two new species of the genus Dahlica Enderlein (Lepidoptera, Psychidae) from Korea

Abstract The genus Dahlica Enderlein, 1912 is reported for the first time from Korea with two new species: Dahlica (Dahlica) somae Roh & Byun, sp. n. and Dahlica (Dahlica) ochrostigma Roh & Byun, sp. n. Adults and genitalia are illustrated, and DNA barcodes for precise identification of the species are also provided.


Introduction
The family Psychidae is a medium-sized family of moths consisting of 241 named genera and 1,350 species (Sobczyk 2011;van Nieukerken et al. 2011). Phylogenetically, Psychidae belong to the oldest clades of the suborder Ditrysia in the order Lepidoptera, and have usually been placed in the superfamily Tineoidea (Davis and Robinson 1998),

Materials and methods
The material examined in this study is preserved in the Systematic Entomology Laboratory, Hannam University (SEL/HNU), Daejeon, Korea, and the Entomological Collection of the Korea National Arboretum, Pocheon, Korea (KNAE). Specimens were dissected and examined after mounting on slide glass; male genitalia and wing scales in 80 % glycerol solution, females in euparal solution and wing venation on dried condition. Photographs of adults and genitalia were taken using a PAXcam digital camera (PAXcam Microscope Cameras Co., Chicago, IL, USA) attached to a Carl Zeiss Axio Imager A1 microscope (Carl Zeiss Ltd., Cambridge, MA, USA).
Genomic DNA was extracted from the legs of dried specimen for males and thorax parts of immersion specimen for females, preserved in 100% alcohol using a Genomic Cell/Tissue Spin Mini Kit (Mbiotech, Inc., Hanam, Korea), according to the manufacturer's protocol. A total of six specimens were sequenced for, the 658 bp fragment of the mitochondrial cytochrome c oxidase I (COI) gene, the DNA barcode, was amplified using the primer pair LepF1 and LepR1 (Hebert et al. 2004). PCR conditions for amplification followed the manufacturer's protocol (Platinum Taq, Invitrogen, Carlsbad City, CA, USA). Amplicons were purified using the QIAquick® PCR purification kit (QIAGEN, Inc.) and directly sequenced at Genotech Corp. (Yuseong-gu, Daejeon, Korea). Contigs were assembled using CodonCode aligner version 2.0.6 (CodonCode Co., Centerville City, MA, USA) and were aligned using MAFFT (Katoh and Toh 2008).
The new barcodes were compared to 18 DNA barcodes of the genera Dahlica and Narycia downloaded from GenBank (National Center for Biotechnology Information, USA, http://www.ncbi.nlm.nih.gov/) (Table 1). A neighbor-joining (NJ) analysis was performed with MEGA 6.0 (Tamura et al 2013) under the K2P model for nucleotide substitutions. Successful sequences were uploaded to BOLD systems (project. KNAE) and submitted to GenBank (Table 1).

Diagnosis.
Male of this species is superficially similar to D. triquetrella (Hübner, 1813), but can be distinguished by a slightly longer transtilla and a relatively short ampulla of the male genitalia (lateral aspect). This species can be readily differentiated by the veins of the male hindwing; M2 and M3 originate at the apical corner of the posterior part of the discoidal cell. Female apophyses posteriores 1.75 times longer than apophyses anteriores.
Description. Adult. Male (Figs 5-12). Wingspan 12.3-13.4 mm ( Table 2). Coloration and vestiture: Vertex of head roughly covered with grayish brown hairs. Thoracic notum covered with blackish brown hairs. Upper side of forewing: ground color grayish black; white spots present regularly; scales ( Fig. 10) slightly narrow and evenly widened apically; apical margin usually produced into two to four laciniations (classes 2-4) ( Table 2). Hindwing covered with grayish white scales; postmarginal part present with slight long shiny white hairs. Structure: head and compound eyes slightly large; ocelli absent. Antennae (Fig. 8) filiform, longer than 2/3 forewing. Forewing: slightly long and narrow; costa straight; termen shortly arched to posterior margin, discoidal cell 0.64 times as long as forewing; venation ( Fig. 28) with nine veins, originating at the discoidal cell; accessory cell present; intercalary cell absent; Sc arising with 3/5 costa; R 2 and R 3 originating at corner of accessory cell; R 4 and R 5 fused and originating at apical corner of anterior part of the discoidal cell reaching to the apex; M 1 and M 2 parallel; M 2 and M 3 stalked at apical corner of posterior part of the discoidal cell; Cu 1 and Cu 2 parallel. Hindwing (Fig. 28): costa straight; discoidal cell 0.51 times as long as hindwing; Sc straight to 4/5 costa; R terminating at apex; M 1 and M 2 parallel, M 2 and M 3 originating at apical corner of posterior part of the discoidal cell (Table 2); Cu 1 and Cu 2 parallel to tornus. Legs: epiphysis absent (Fig. 9); femora and tibiae covered with brown hairs; tarsi covered with grayish brown scales.
Female (Figs 24-27). Adult 4.2 mm in length. Coloration: Head, meso-, and metanotum dark brown. Membranous areas of abdomen yellowish brown. Abdomen covered with light brown scales; corethrogyne densely covered with white hairs on ventral part only. Structure: apterous. Head and compound eyes small, antennae slightly developed with basal flagellomeres 17 segmented, bipectinated. Legs well developed with tarsi divided into four tarsomeres; hind legs present with apical spurs.
Male genitalia (Figs 11, 12). In lateral aspect. Genitalia index, 1.46-1.56 (Table 2). Dorsum gently curved. Saccus very short; ampulla narrow and short with club shape, setae present sparsely; harpe short with hooked shape; phallus slender and very long with whip shape. In dorso-ventral aspect, uncus slightly concave; gnathos and juxta absent; valva slightly narrow, apical part of valva densely covered. Female genitalia (Fig. 27). Oviscapt and ostium bursae well sclerotized. Apophyses posteriores 1.75 times longer than apophyses anteriores, very slender. Sclerotizations of the seventh sternite present with bundle of hairs DNA barcode. DNA barcode sequences were generated from three individuals. Multiple alignments using the BLAST tool in the NCBI database showed the following species as nearest neighbor: Dahlica charlottae with a similarity between 97 and 95%.
Etymology. The species is named in honor of Ms. Da-Som Kim, collector of the material. Diagnosis. Male, this species is superficially similar to D. somae sp. n., but can be distinguished by slightly shorter antennae, a narrow forewing, and the venation of hindwing M3 stalked at 1/4 of M2. This species can be readily differentiated by the dorsum of male genitalia, which is strongly arched to the apical part and in the shape of a hat, and a very short phallus (lateral aspect). Female, apophyses posteriores 1.16 times longer than apophyses anteriores.

Dahlica
Description. Adult. Male (Figs 13-19). Wingspan 9.8-11.2 mm ( Table 2). Coloration and vestiture: Vertex of head roughly covered with short grayish brown hairs. Thoracic notum covered with brown hairs. Upper side of forewing: ground color gray with sparsely yellow spots; scales (Fig. 16) considerably narrow; apical margin usually produced into two to three laciniations (classes 1-2) ( Table 2). Postmarginal part of hindwing present with long shiny white hairs. Structure: head slightly small, compound eyes relatively large; ocelli absent. Antennae filiform (Fig. 15), less than 1/2 forewing. Forewing: short and narrow; costa straight; apex strongly arched to termen, discoidal cell 0.67 times as long as forewing; venation ( Fig. 29) with nine veins, originating at the discoidal cell; intercalary cell absent and accessory cell present; Sc reaching to 3/5 costa;   R 4 and R 5 fused; R 3 and R 4 + R 5 originating at apical corner of anterior part of discoidal cell; M 1 and M 2 parallel; M 2 and M 3 stalked at apical corner of posterior part of the discoidal cell; Cu 1 and Cu 2 parallel. Hindwing (Fig. 29): costa straight; discoidal cell 0.52 times as long as hindwing; Sc straight and reaching to 4/5 costa; R originated at apical corner of anterior part of discoidal cell and reaching the apex; M 1 and M 2 parallel, M 3 stalked at 1/4 M 2 (Table 2); Cu 1 and Cu 2 parallel. Legs covered with shiny brown scales, epiphysis absent (Fig. 17).
Female . 4.5 mm in length. Coloration: Head dark-brown. Meso and metanotum red-brown. Membranous areas of abdomen yellow. Abdomen clothed with light brown scales; corethrogyne densely covered with yellowish white hairs at only ventral part. Structure: Apterous. Head slightly small, antennae relatively developed and long. Legs well developed, slightly long, tarsi 4-segmented.
Male genitalia (Figs 18, 19). In lateral aspect. Genitalia index, 0.79-1.08 (Table 2). Dorsum strongly arched to apical part with the shape of a hat. Saccus relatively short; ampulla slightly long and club shape, setae sparsely; harpe short with needle shape; phallus slender and short with whip shape. In dorso-ventral aspect, uncus slightly concave shape; gnathos and juxta absent; valva slightly narrow and apical part produced into weak rounded claviform.
Distribution. Korea. DNA barcode. DNA barcode sequences were generated from three individuals (Table 1). Multiple alignments using the BLAST tool in the NCBI database showed the following species as nearest neighbor, Dahlica charlottae with a similarity between 96 and 94%.
Etymology. The specific name is derived from the Greek words ochro and stigma (= pale spots), referring to the forewing pattern.

Discussion
The taxonomy of Dahlica has until recently been confusing owing to the similar morphology of the species in this genus and those in the allied genera Siederia, Postsolenobia, Brevantennia, and Praesolenobia. The proposal by Arnscheid and Weidlich (2017) to treat all these as subgenera of Dahlica has partly solved this problem. In this study, two new Korean species of Dahlica were reported for the first time with COI barcodes ( Table 1). The results of comparison with related taxa, including subgenera of Dahlica, revealed no distinct differences (Fig 36). Therefore, the taxonomic positions of the species in genus Dahlica needs to be redefined through future systematic studies with additional samples.
Most species of the genus Dahlica have been reported from Europe (48 species) to date, only one species, D. (D.) parthenogenesis Saigusa, 1961 was collected in Japan (Saigusa 1961). Thus, the two new species described in this study represent the first records for continental East Asia and serve as important basic data for future research on this genus and allied taxa in Asia.