Quadriops dentatus Hansen, 1999

Giron, Jennifer C. & Short, Andrew Edward Z., 2017, Revision of the Neotropical water scavenger beetle genus Quadriops Hansen, 1999 (Coleoptera, Hydrophilidae, Acidocerinae), ZooKeys 705, pp. 115-141 : 122

Quadriops dentatus Hansen, 1999 Figs 1 A–D, 9B

Quadriops dentatus Hansen, 1999: 134.

Type material examined.

Holotype (female): "VENEZ [Venezuela]: Bolivar/ 105 km S El Dorado/ 17. VII– 7.VIII.86/ B. Gill 350m", "Flight intercept/ trap", “HOLOTYPE”, "[Handwritten] HOLOTYPE/ Quadriops dentatus / M. Hansen", "[Barcode] Canadian Museum of/ Musée canadien de la/ NATURE/ CMNEN 0011502" (CMNC).

Additional material examined

(5 exs.). FRENCH GUIANA: Matoury: 41.5 km SSW on Hwy N2, 4°37'22"N, 52°22'35W, 50m, 29 May– 9 Jun 1997, J. Ashe, R. Brooks, FG1A97 170, ex: flight intercept trap // Barcodes: SM0134289 (SEMC, 1 female), SM0134241 (SEMC, 1 female, dissected); Roura: 8.4 km SSE, 200 m, 4°40'41"N, 52°13'25"W, 25-29 May 1997, J. Ashe, R. Brooks, FG1AB97 088, ex: flight intercept trap // Barcode: SM0096111 (SEMC, 1 female); 13.0 km SSE, 240 m, 4°38'38"N, 52°17'56"W / 13 Jun 1997; J. Ashe, R. Brooks, FG1AB97 196, ex: miscellaneous collecting // Barcode: SM0100061 (SEMC, 1 female). SURINAME: Sipaliwini: Camp 4 (low), Kasikasima, 2.97731°N, 55.38500°W, 200m, 20-25 mar 2012, leg. Larsen, flight intercept trap, SR12-0320-TN1, 2012 CI-RAP Survey // Barcode: SEMC1089659 (SEMC, 1 female).

Differential diagnosis.

Quadriops dentatus is very similar to Q. acroreius , both species being moderately convex (as opposed to dorsally flattened) and the serial punctures of the elytra are randomly and uniformly distributed, not aligned to form well defined longitudinal rows. It can be easily distinguished by the toothlike projection of the mesoventrite (as opposed to a wide, transverse, straight, blunt carina as in Q. acroreius ); in addition, the surface of head and clypeus is smooth between punctures (as opposed to reticulated).

Redescription.

Body length 1.6-2.2 mm, width 1.1-1.2 mm. Body elongate oval, moderately convex. General coloration uniform yellowish to dark brown. Surface smooth (as opposed to reticulated between punctures) on head, pronotum and elytra. Elevation of mesoventrite forming a basally transverse acute tooth. Metaventrite with a posterior, short, glabrous and narrow stripe. Elytra with randomly and uniformly distributed punctures, not aligned into striae; surface of pseudepipleura smooth throughout, at most only slightly reticulated at base. Metafemora with pubescence only along dorsal area of articulation to trochanter.

Variation.

There is variation in size with the type specimen being the largest.

Distribution.

Venezuela ( Bolívar), Suriname (Sipaliwini), French Guiana (Matoury, Roura). See Fig. 9B.

Biology.

The male of this species remains unknown. All known specimens were collected using flight intercept traps, at elevations between 50 and 350 m.