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Home » Guide » Arthropods (Arthropoda) » Hexapods (Hexapoda) » Insects (Insecta) » Beetles (Coleoptera) » Adephaga » Predaceous Diving Beetles (Dytiscidae) » Coptotominae » Coptotomus

Genus Coptotomus

Coptotomus venustus (Say) - Coptotomus venustus - female

Classification

Kingdom Animalia (Animals)

Phylum Arthropoda (Arthropods)

Subphylum Hexapoda (Hexapods)

Class Insecta (Insects)

Order Coleoptera (Beetles)

Suborder Adephaga

Family Dytiscidae (Predaceous Diving Beetles)

Subfamily Coptotominae

Genus Coptotomus

Synonyms and other taxonomic changes

genus needs revision mainly because of high morphological similarity between adults of various species and possible hybridization/intergradation of individuals once deemed as separate species(1)

Explanation of Names

Coptotomus Say 1834

Greek copto 'cut, strike' + tomos 'part'

Numbers

5 spp. total in genus, plus one subspecies; 4 spp. north of Mexico, 1 sp. in Mexico known only from type specimen; perhaps additional undescribed species or synonyms; genus requires revision (1)

Size

5.7-8.6 mm(1)

Identification

Adults:

generally elongate-oval in shape, with the surface of the elytra variously maculate (patterned)

eyes notched at antennal bases

labial and maxillary palps notched apically on the last (outermost) segment (separates from all othe genera in the subamily)

Larvae:

Can be easily separated from other dytiscid larvae as they have elongated lateral abdominal gills.

Species identification of adults relies on examination of technical features such as colouration/patterning, characters on the underside (e.g. metasternal wing width), and genitalia.

Range

transcontinental, Canada to n. Mexico(2)

Habitat

Deeper sections of permanent ponds with emergent vegetation, lakes and slowly flowing streams(2)

Print References

Hilsenhoff W.L. (1980) Coptotomus (Coleoptera: Dytiscidae) in eastern North America with descriptions of two new species. Trans. Am. Ent. Soc. 105: 461-471.

Works Cited

1.	Predaceous Diving Beetles (Coleoptera: Dytiscidae) of the Nearctic Region, with emphasis on the fauna of Canada and Alaska D.J. Larson, Y. Alarie, and R.E. Roughley. 2001. NRC 43253.

2.	American Beetles, Volume I: Archostemata, Myxophaga, Adephaga, Polyphaga: Staphyliniformia Arnett, R.H., Jr., and M. C. Thomas. (eds.). 2000. CRC Press LLC, Boca Raton, FL.

Contributed by Jim McClarin on 16 June, 2006 - 8:19pm
Additional contributions by Mike Quinn, t.loh, v belov, mpintar
Last updated 2 July, 2023 - 12:59am

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