Hydraena fasciolata, 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 : 120-121

Hydraena fasciolata , new species

( Figs. 219 , 221 , 530 )

Type Material. Holotype (male): Madang Province: Madang, Ohu Village , 160 m, 5° 13.923' S, 145° 40.763' E, 30 iv 2006, Balke & Sagata ( PNG 49) ( ZSM).

Differential Diagnosis. A distinctively banded, very broad species. Somewhat similar to H. dudgeoni in habitus, both having a very transverse pronotum ( Figs. 218 , 219 ), but more markedly color banded, and with more widely spaced coxae (plaque ratios ca. 9/1/6/8 vs. 7/1/6/8). This species has the widest separation of the mesocoxae. The male genitalia of the two species differ markedly ( Figs. 220, 221 ).

Description. Size: holotype (length/width, mm): body (length to elytral apices) 1.44/0.68; head 0.23/0.35; pronotum 0.36/0.55, PA 0.43, PB 0.46; elytra 0.84/0.68. Dorsum very distinctively banded: labrum and clypeus light brown to testaceous; frons dark brown; pronotum testaceous; elytra dark brown with light brown to testaceous fascia at posterior declivity, and similarly colored band across elytral apices; legs and maxillary palpi testaceous, tip of palpus not darker.

Frons punctures ca. 1xef, slightly larger near eyes than medially; interstices shining, 2–4xpd. Clypeus microreticulate laterally, very finely sparsely punctate medially. Mentum and postmentum very sparsely very finely punctulate, shining. Genae raised, shining, without posterior ridge. Pronotum very transverse, sides markedly rounded, ca. median 5/7 of anterior margin arcuate to posterior; punctures on disc ca. 1xpd frons punctures, interstices shining, 1–2xpd, punctures not appreciably larger or denser at anterior and posterior; PF1 absent; PF2 absent or so shallow as to be almost imperceptible; PF3 shallow; PF4 absent.

Elytra with summit of posterior declivity anterior to midlength; lateral explanate margins rather wide in anterior 1/2 where sides of elytra gradually sloping; on basal 1/3 punctures ca. 1xpd largest pronotal punctures, a few punctures subserial, punctures becoming gradually smaller toward posterior. Intervals not raised, shining, on disc ca. 2–5xpd, 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. 9/1/6/8. P1 ca. 2/3 P2; median carina straight in profile; postcoxal process medially concave. P2 transversely concave, l/w ca. 4/9, sides slightly diverging toward blunt apex. Plaques very narrow, carinate, very slightly arcuate, converging slightly anteriorly, at sides of deep median depression. Metaventrite concave between P2 and plaques. AIS width at straight posterior margin ca. equal P2. All legs rather short, moderately slender. Profemur (male) with small tubercle next to trochanter; protibia arcuate. Meso- and metatibia straight. Abdominal apex symmetrical; last tergite (male) deeply notched. Aedeagus as illustrated ( Fig. 221 ).

Etymology. Named in reference to the dorsal fasciae, and wide body.

Distribution. Currently known only from the type locality, Ohu Village, in the northwestern part of Area 5; elevation 160 m ( Fig. 530 ).

Figures

FIGURE 218. Hydraena dudgeoni, holotype, dorsal and lateral habitus, and venter.

FIGURE 219. Hydraena fasciolata, holotype, dorsal and lateral habitus, and venter.

FIGURES 220–221. Aedeagi of holotypes. 220. H. dudgeoni. 221. H. fasciolata.

FIGURES 527–530. Geographical distributions of Hydraena species.