Parhydraenopsis, Perkins, 2009

Perkins, Philip D., 2009, Revisions of the genera Parhydraena Orchymont, Protozantaena Perkins, Decarthrocerus Orchymont, and Parhydraenopsis nomen novum, aquatic and humicolous beetles from Africa and Madagascar, and comparative morphology of the tribe Parhydraenini (Coleoptera: Hydraenidae), Zootaxa 2038, pp. 1-119 : 48-49

Parhydraenopsis nomen novum

Pseudhydraena Orchymont, 1947: 721 (junior homonym of Pseudhydraena Acloque, 1896; see Hansen 1998). Type species: Parhydraena cooperi Orchymont , by original designation.

Parhydraena (Decarthrocerus) : Perkins, 1997: 174. (Pseudhydraena as junior synonym of Decarthrocerus ).

Parhydraena (Decarthrocerus) : Hansen, 1998: 62 (catalog).

Diagnosis. Distinguished from Parhydraena and Decarthrocerus by the lack of an hypomeral carina; further distinguished from Decarthrocerus by the markedly different habitus ( Fig. 1). Distinguished from Discozantaena by the presence of hypomeral antennal pocket setae, and the markedly different habitus. Distinguished from Protozantaena by the much larger size, the more convex form, the different elytral puncture pattern, and the markedly different aedeagal form. Recognized by the moderately large size (length ca. 2.12–2.38 mm); the transversely moderately convex body form; the ten-articled antenna (five + club); the lack of an hypomeral carina; the hypomeral antennal pocket setae forming a moderately strong cup; the weakly to moderately developed ocelli located between the midline and the eyes; the densely punctate pronotum with anterior hyaline margin and lacking postocular emarginations, and the elytra with some random punctures, and with setae of punctures and intervals very similar.

Description. Body size moderately large, length ca. 2.12–2.38 mm; form elongate oval, transversely convex dorsally, weakly to moderately explanate, head not deflexed. Antennomeres ten (five + club), second slightly longer than combined lengths of third to fifth. Maxillary palpus moderately robust, total length varying only slightly, length/head width ca. 0.42–0.57; ratios of articles two to four (last) variable, but fourth always longest and third always shortest (e.g., 6/4/9 and 10/5/12). Eyes well-developed, not elevated, 9–10 facets in longest series in dorsal aspect. Labrum set at an angle to clypeus, about same length or slightly shorter than clypeus, shape of anterior margin straight to weakly emarginate. Clypeus anterior margin and frontoclypeal suture slightly arcuate. Ocelli weakly convex, located midway between midline and eyes. Frons very weakly convex between ocelli; area behind and between ocelli lacking carinae. Pronotum densely coarsely punctate, punctures paired, disc with anterior and posterior transverse U-shaped impressions; anterior hyaline border present over median third, narrow. Hypomeron lacking carina at margin of hydrofuge pubescence; antennal pocket bordered by row contiguous, arcuate setae forming cup. Proventral antennal cleaner, a dense cluster of sharp spines, located on anterolateral margin of each side of proventrite. Metaventrite with shallow impression on disc in basal 1/2, midlongitudinal carina between impression and mesoventral intercoxal process. Elytra with ten rows of punctures, six between suture and humerus, except some series near base random; serial punctures and punctures on intervals very similar, setae of each very similar, short. Intercoxal sternite small, triangular. Aedeagus with distal piece articulated on main-piece; parameres, when present, minute, each with two setae.

N otes. Hansen (1998) was the first to point out that Pseudhydraena Orchymont, 1947 is a junior homonym of Pseudhydraena Acloque, 1896. Hansen (1998: 92) also established Pseudhydraena Acloque as a junior synonym of the subgenus Ochthebius (s. str.) Leach, and designated Elophorus marinus Paykull as the type species of Pseudhydraena Acloque.

Orchymont (1947, 1948) stated that the aedeagus of Parhydraena (Pseudhydraena) cooperi Orchymont (now the type species of Parhydraenopsis ) did not have parameres; also, Orchymont (1947) illustrated the aedeagus without parameres. Following those papers, Perkins (1997: 174) also stated, incorrectly, that parameres were absent. In fact, with very high magnification, the aedeagus is seen to have a very short paramere on the right side, and two paramere-derived setae (no paramere) on the left side ( Fig. 80).