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  When still in larval form, the beetles vary in size from about 1 to 5 cm (0.5 to 2.0 in). The larval bodies are shaped like crescents, with the tail long and covered with thin hairs. Six legs protrude from along the 胸, which also sports the same thin hairs. The head is flat and square, with a pair of long, large pincers. When hunting, they cling to grasses or pieces of wood along the bottom, and hold perfectly still until prey passes by, then they lunge, trapping their prey between their front legs and biting down with their pincers. Their usual prey includes 蝌蚪s and s, among other smaller water-dwelling creatures.  As the larvae mature, they crawl from the water on the sturdy legs, and bury themselves in the mud for 蛹. After about a week, or longer in some species, they emerge from the mud as adults.

  本科物種的成蟲,特別是"Cybister"屬的物種,均為可食用昆蟲。在美國內華達州洪堡幹湖的一個山洞內,還在當地史前人類遺下的糞化石內發現有'被食用的殘骸。在墨西哥,他們在吃"C. explanatus"時會以墨西哥夾餅夾著來吃。在日本多個地區(例如:長野縣)有以日本龍蝨(')為食的習慣;在中華人民共和國廣東省,除了日本龍蝨以外,亦會食用"C. bengalensis"、"C. guerini"、"C. limbatus"、"C. sugillatus"、"C. tripunctatus"等物種。"D. marginalis"很可能也包括在內,但這個物種的肉很少。也有報告指在臺灣、泰國及新幾內亞亦有食用本科物種的習慣。  Large but slow on land and not particularly fierce as adults, they are also eaten with relish by many midsized 鳥s, 哺乳動物s, and other larger 捕食s. The larvae are usually safer, due to their 保護色 and ability to escape by water jet; they can be quite hard to catch and may become 頂級掠食者s in small 池塘s.

  The diving beetle plays a role in a 切羅基人 creation story. According to the narrative, upon finding nowhere to rest in the "liquid chaos" the beetle brought up soft mud from the bottom. This mud then spread out to form all of the land on Earth.

  Adult Dytiscidae, as well as 豉甲科, are collected by young girls in 東非. It is believed that inducing the beetles to bite the nipples will stimulate breast growth.

  蟎 of the genus "Dytiscacarus" were found to be are highly specialised 寄生 of 鞘翅目 in the family Dytiscidae, undergoing their entire life cycle while inhabiting the space beneath the 翅鞘 of their hosts.

  本科包括下列各屬:
龍蝨科(),亦作龍蝨科,為水甲蟲的一種,隸屬於鞘翅目之下的肉食亞目。生活在田野、水溝、小溪等水體中,是一種掠食性水生昆蟲。其學名源於希臘文'("dytikos"),意思就是「肉食性的潛水甲蟲」。本科物種幾乎見於全世界所有淡水棲境,但亦有部分於落葉堆中棲息。成蟲體長一般在之間,儘管物種間的差異會比較大。當中見於歐洲的'及巴西的""有最大的體型,可分別長至到。與之相反,擁有最小體型的物種應當為棲息於澳大利亞地下水中的" atypicali",只有約長。 大多數物種的顏色都在深棕色、黑色或深橄欖綠,某些亞科的物種會在其邊沿帶有金黃色的條狀斑紋。 They have short, but sharp s. Immediately upon biting, they deliver digestive enzymes. The 幼體e are commonly known as water tigers. The family includes more than 4,000 described 物種 in numerous 屬.