Hydraena copulata, 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 : 71-72

Hydraena copulata , new species

( Figs. 115 , 117 , 484 )

Type Material. Holotype (male): Gulf Province: Marawaka , Mala, 1400 m, 7° 5.664' S, 145° 44.467' E, 11 xi 2006, Balke & Kinibel ( PNG 90) ( ZSM) . Paratype: Same data as holotype (1 female ZSM) .

Differential Diagnosis. Among members of the Velvetina group, somewhat similar in habitus to H. incista ( Figs. 114 , 115 ); distinguished therefrom by the wider pronotal shape (PL<PW vs. PL=PW), the non-depressed mesoventral intercoxal process, and the midlongitudinal extension of pronotal fovea PF1. The aedeagi of the two species distinctively differ ( Figs. 116, 117 ).

Description. Size: holotype (length/width, mm): body (length to elytral apices) 1.78/0.72; head 0.26/0.37; pronotum 0.43/0.45, PA 0.37, PB 0.36; elytra 1.08/0.72. Dorsum piceous, except light brown to testaceous band across anterior 1/6 of pronotum, legs and maxillary palpi brown to reddish brown, distal 1/3 of last palpomere darker.

Frons with depressed area next to each eye, punctures less than 1xef; interstices 2–4xpd; depressed areas microreticulate, dull or very weakly shining, disc more strongly shining,. Clypeus microreticulate laterally, very finely sparsely punctate medially. Mentum concave, very sparsely very finely punctulate, shining. Genae raised, shining, with tiny median impression, without posterior ridge. Pronotum cordiform, anterior margin slightly arcuate; punctures on disc ca. 1xef, interstices shining, 2–4xpd, punctures slightly larger and denser at anterior and posterior; PF1 with shallow midlongitudinal extension to ca. middle of disc; PF2 deep, large, oval, oblique, confluent, together forming U-shaped impression; PF3 deep; PF4 moderately deep.

Elytra convex, summit of posterior declivity slightly before midlength; lateral explanate margins moderately wide; on basal 1/3 punctures ca. 1xpd largest pronotal punctures, punctures becoming gradually smaller toward posterior. Intervals not raised, shining, on disc ca. 1–3xpd, as are interstices between punctures of a row. Apices in dorsal aspect conjointly rounded, in posterior aspect margins forming angle with one another.

P1 laminate; median carina very low, not sinuate in profile. P2 not raised, very short, much shorter than and confluent with metaventral intercoxal process. Plaques absent, hydrofuge pubescence longest at sides of deep median depression. AIS width at straight posterior margin ca. 3x P2. All legs long and slender, except profemur more robust. Profemur (male) without tubercle next to trochanter; protibia straight, medial margin gradually widening from base to ca. distal 1/4, then emarginate and with flat surface to apex, widest point with large spine, emargination with row of short spines. Mesotibia straight. Metatibia straight, with few setae on medial margin subapically; metatarsi with long setae on basal tarsomeres. Abdominal apex symmetrical; last tergite (male) notched.

P1 laminate; median carina sinuate in profile. P2 raised, l/w ca. 2/1, sides slightly converging toward apex. Plaques absent, hydrofuge pubescence longest at sides of deep median depression. AIS width at straight posterior margin ca. 2x P2. All legs long and very slender. Profemur (male) without tubercle next to trochanter; protibia straight, medial margin gradually widening from base to slightly past midlength, then decreasing in width to slightly hooked apex, widest point with several large spines, between these spines and apex with row of short spines, anterior face of protibia flat. Meso- and metatibiae straight. Abdominal apex symmetrical; last tergite (male) notched. Aedeagus ( Fig. 117 ) distal piece with several smaller processes and one large, strong, hook-shaped process. Female with depressions on frons like those of male.

Etymology. "Joined"; named in reference to the fact that the holotype and only known female were collected in copulo ( Fig. 8 ), and also named in reference to the very strong and large hook-shaped process of the aedeagus.

Distribution. Currently known only from the type locality near Marawaka, in the southeastern extreme of Area 1; elevation 1400 m ( Fig. 484 ).

Figures

FIGURE 114. Hydraena incista, holotype, dorsal and lateral habitus, and venter.

FIGURE 115. Hydraena copulata, holotype, dorsal and lateral habitus, and venter.

FIGURES 116–117. Aedeagi of holotypes. 116. H. incista. 117. H. copulata.

FIGURES 483–486. Geographical distributions of Hydraena species.

FIGURES 4–9. 4–7. Pronotal sculpture and measurements. 8. H. copulata, holotype male and paratype female in copula. 9. Metavental structures and measurements.