Hydraena photogenica, 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 : 139-140

publication ID	https://doi.org/ 10.11646/zootaxa.2944.1.1
DOI	https://doi.org/10.5281/zenodo.5291843
persistent identifier	https://treatment.plazi.org/id/03B087E5-5BEF-FF18-FF79-F0D1FE43FEF2
treatment provided by	Felipe
scientific name	Hydraena photogenica
status	sp. nov.

Treatment

Hydraena photogenica View in CoL , new species

( Figs. 258 View FIGURE 258 , 260 View FIGURES 260–261 , 553 View FIGURES 551–554 )

Type Material. Holotype (male): Eastern Highlands Province: Goroka , Mt. Gahavisuka, 2200 m, 6°.896' S, 145° 24.753' E, 8 iv 2006, Balke & Sagata ( PNG 35) ( ZSM) . Paratypes (4): Eastern Highlands Province: Same data as holotype (3 ZSM); Kainantu, Yoginofi, 1900 m, 6° 21.799' S, 145° 45.463' E, 9 v 2006, Balke & Sagata ( PNG 55) (1 ZSM) GoogleMaps .

Differential Diagnosis. Similar in dorsal habitus to H. fundarca ( Figs. 254 View FIGURE 254 , 258 View FIGURE 258 ); dorsally differing therefrom in slightly less angulate sides of the pronotum and slightly more narrowly rounded elytral apices. The metaventral plaques differ distinctively in the two species: in H. photogenica the plaques are more narrowly separated, shorter, less arcuate, and evenly carinate (plaque ratios ca. 4/1/6/4 vs. 5/2/10/7). Males of H. photogenica lack the markedly modified pro- and metatibiae present in H. fundarca . The male genitalia of the two species bear some general resemblance, but differ distinctively in many details ( Figs. 256 View FIGURES 256–257 , 260 View FIGURES 260–261 ).

Description. Size: holotype (length/width, mm): body (length to elytral apices) 1.56/0.67; head 0.23/0.36; pronotum 0.39/0.55, PA 0.42, PB 0.50; elytra 0.94/0.67. Dorsum of head with frons dark brown to piceous, clypeus brown, labrum light brown to testaceous; pronotum light brown around dark brown, diffusely margined, rectangular macula, ratios of color bands, as measured in midline, ca. 8/12/6; elytra dark brown; legs light brown; maxillary palpi testaceous, tip not darker. Dorsum shining.

Frons punctures ca. 1xef near eyes, smaller and much sparser medially; interstices shining, 1–5xpd. 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, with shallow, obsolete median impression, 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 very slightly larger than those on disc; PF1, PF2 and PF4 absent; PF3 shallow, wide.

Elytra widest at about midlength; summit of posterior declivity at or very near midlength; lateral explanate margins moderately wide; on basal 1/3 punctures ca. 1xpd of largest pronotal punctures, a few punctures subserial, punctures becoming gradually smaller toward posterior. Intervals not raised, shining, on disc ca. 2–3xpd, 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. 4/1/6/4. P1 laminate; median carina nearly straight in profile, very slightly arcuate between coxae. P2 markedly concave, length/width ca. 3/2, sides very slightly diverging toward blunt, slightly concave apex. Plaques low carinate lines, converging anteriorly, at sides of median depression. Metaventrite flat between mesocoxae. AIS width at straight posterior margin slightly greater than P2. All legs of moderate length. Profemur (male) with very small tubercle on ventral margin near basal 1/3; protibia straight, medial margin slightly widened in distal 1/2. Meso- and metatibia straight, slender. Abdominal apex symmetrical; last tergite (male) with apicomedian notch. Aedeagus as illustrated ( Fig. 260 View FIGURES 260–261 ).

Etymology. A photogenic species (see Fig. 258 View FIGURE 258 ).

Distribution. Currently known from two moderately closely spaced localities in eastern Area 1; elevations 1900 m and 2200 m ( Fig. 553 View FIGURES 551–554 ).