Hydraena fundapta, Perkins, 2011

Perkins, Philip D., 2011, New species (130) of the hyperdiverse aquatic beetle genus Hydraena Kugelann from Papua New Guinea, and a preliminary analysis of areas of endemism (Coleoptera: Hydraenidae) 2944, Zootaxa 2944 (1), pp. 1-417 : 138-139

Hydraena fundapta , new species

( Figs. 255 , 257 , 556 )

Type Material. Holotype (male): Central Province: Port Moresby – Brown River road, ex small pool in dry gravelly stream bed, [GE est.] 50–100 m, 9° 24' S, 147° 14' E, 15 iii 1965, M. E. Bacchus (MEB 196) ( NHM) . Paratypes: Same data as holotype (1 NHM) .

Differential Diagnosis. Differentiated from other members of the Fundarca group by the shape of the metaventral plaques and the plaque ratios (ca. 5/2/6/4). This is the only species in the group that has P2 wider than the distance between the plaques ( Fig. 255 ). The aedeagus is very distinctive; the large lobe on the right side of the main piece is covered in velcro-like spicules in this species, whereas in the other members of the group the lobe bears short setae ( Fig. 257 ).

Description. Size: holotype (length/width, mm): body (length to elytral apices) 1.35/0.59; head 0.20/0.34; pronotum 0.34/0.49, PA 0.39, PB 0.47; elytra 0.83/0.59. Dorsum of head dark brown, clypeus and labrum slightly lighter; pronotum testaceous around dark brown, diffusely margined, rectangular macula, ratios of color bands, as measured in midline, ca. 7/12/6; elytra brown; legs light brown; maxillary palpi testaceous, tip not darker. Dorsum moderately shining.

Frons punctures ca. 1xef near eyes, smaller and sparser medially; interstices shining, 1–4xpd. Clypeus effacedly microreticulate laterally, very finely sparsely punctulate and shining medially. Mentum very sparsely very finely punctulate, shining. Postmentum effacedly microreticulate in shallow median depression, otherwise finely sparsely punctate. Genae very slightly raised, shining, without posterior ridge. Pronotum transverse, ca. median 3/4 of anterior margin slightly arcuate to posterior, sides weakly arcuate, slightly emarginate between midlength and posterior angle; punctures on disc ca. 1xpd largest frons punctures, interstices shining, ca. 2–5xpd, punctures anteriorly and posteriorly slightly larger than those on disc; PF1 and PF4 absent; PF2 very shallow, completely shallowly confluent in midline to form U-shaped impression; PF3 moderately deep, wide.

Elytra widest at about anterior 1/3; summit of posterior declivity at or very near midlength; lateral explanate margins moderately wide; on basal 1/3 punctures slightly smaller than largest pronotal punctures, a few punctures subserial, punctures becoming gradually smaller toward posterior. Intervals not raised, shining, on disc ca. 2–4xpd, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins forming shallow angle with one another.

Ratios of P2 width and plaque shape (P2/w/l/s) ca. 5/2/6/4. P1 very slightly wider than laminate; median carina nearly straight in profile, very slightly arcuate between coxae. P2 markedly concave, length/width ca. 6/5, sides very slightly diverging toward blunt, transversely slightly concave apex. Plaques slightly raised, converging, but not becoming confluent, anteriorly, at sides of inverted V-shaped median depression. Metaventrite between mesocoxae slightly sloping, confluent with tip of P2. AIS width at straight posterior margin ca. equal P2. All legs of moderate length. Profemur (male) without tubercle on ventral margin near basal 1/3; protibia slightly arcuate, gradually increasing in width from base to apex, medial margin flat. Meso- and metatibia straight, slender. Abdominal apex symmetrical; last tergite (male) with apicomedian notch. Aedeagus as illustrated ( Fig. 257 ).

Etymology. Named in reference to the relationship to H. funda , and to the prominent lobe of the aedeagus, which is covered with velcro-like spines.

Distribution. Currently known only from the type locality near Port Moresby; this is in central Area 11, elevation 50–100 m ( Fig. 556 ).

Figures

FIGURE 255. Hydraena fundapta, holotype, dorsal and lateral habitus, and venter.

FIGURES 256–257. Aedeagi of holotypes. 256. H. fundarca. 257. H. fundapta.

FIGURES 555–558. Geographical distributions of Hydraena species.