Hydraena pugillista, Published, 2007

PERKINS, PHILIP D., 2007, A revision of the Australian species of the water beetle genus Hydraena Kugelann (Coleoptera: Hydraenidae), Zootaxa 1489 (1), pp. 1-207 : 46-47

Hydraena pugillista new species

(Figs. 65, 72, 248)

Type Material. Holotype (male): Queensland, 7 km N Mt. Spurgeon , rainforest, sieved litter, Q. M. berlesate No. 857, elev. 1250 m, 16° 22' S, 145° 13' E, 20 October 1991, Monteith & Janetzki. Deposited in the QMBA.

Differential Diagnosis. Similar to H. cultrata and H. bidefensa in color pattern, with pronotum unicolorous, contrasting with the darker brown head and elytra, and the narrow, partially carinate, widely separated

plaques (Figs. 65, 66, 173); differing therefrom by the deeper pronotal foveae PF2, which are united to form a U-shaped impression, the stronger microreticulation of the pronotal depressions, the more regular elytral series, and details of the plaque shape. The aedeagus of H. pugillista differs distinctively from those of the compared species (Figs. 69, 70, 72).

Description. Size (length/width, mm) holotype: body (length to elytral apices) 1.40/0.59; head 0.21/ 0.33; pronotum 0.35/0.48, PA 0.38, PB 0.42; elytra 0.87/0.59. Head and elytra dark brown; pronotum, legs and palpi brown to light brown, tip of palpi not darker.

Frons shining on disc, effacedly microreticulate laterally, punctures slightly less than 1xef; interstices on disc 2–4xpd. Clypeus microreticulate. Mentum and postmentum dull, microreticulate. Genae weakly raised, lacking posterior ridge. Pronotum shining on disc, microreticulate and dull laterally, punctures on disc ca. 2xpd those of frons, interstices 2–5xpd; punctures anteriorly and posteriorly slightly larger than those on disc, interstices ca. 2–3xpd; PF1 and PF4 absent; PF2 shallow, microreticulate, confluent with one another medially, forming u-shaped impression; PF3 moderately deep, broad.

Elytra strongly shining, punctures slightly larger than largest pronotal punctures; punctures becoming smaller and shallower over posterior declivity. Intervals not raised, width ca. 2–3xpd, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins form weak angle with one another.

Ratios of P2 width and plaque shape (P2/w/l/s) ca. 3/1/10/4. P1 laminate; median carina angulate in profile. P2 narrow, l/w ca. 5/3, sides weakly arcuate, apex blunt. Plaques located in posterior 2/3 of metaventrite on sides of deep, median, subtriangular depression; plaques narrow, weakly arcuate, carinate in posterior 1/2, narrowly separated anteriorly. AIS flat, width at arcuate posterior margin ca. 2x P2. Profemur with minute sharp tubercle on medial surface near basal 1/3; protibia slightly arcuate, distinctively thickened, widest at distal 2/3; mesotibia and metatibia simple. Last sternite symmetrical or nearly so; last tergite slightly asymmetrical, with apical, slightly off-center concavity.

Aedeagus (Fig. 72) main-piece with very large lobe on right side, boxing glove-shaped in lateral view; distal piece with narrow terminal lobe, gonopore bearing flagellum at right angle to terminal lobe; left paramere shorter than right, setae in row along ventral margin of widened distal 1/2; right paramere widened from near base, nearly straight, setae in row along slightly angulate, slightly widened distal end. Females not yet known.

Etymology. Named in reference to the boxing glove-shaped process of the aedeagus.

Distribution. Currently known only from the type locality near Mt. Spurgeon, northeastern Queensland (Fig. 248).