Protozantaena palpalis, Perkins, 2009

Perkins, Philip D., 2009, Revisions of the genera Parhydraena Orchymont, Protozantaena Perkins, Decarthrocerus Orchymont, and Parhydraenopsis nomen novum, aquatic and humicolous beetles from Africa and Madagascar, and comparative morphology of the tribe Parhydraenini (Coleoptera: Hydraenidae), Zootaxa 2038, pp. 1-119 : 44-45

Protozantaena palpalis new species

( Figs. 71, 73, 101)

Type material. Holotype (male): Madagascar: Antananarivo, Anjozorobe, Ravoandrina, left affluent of River Ampanakamonty , upstream from site (13), draining a forest clearing, elev. 1230 m, 18° 24' S, 47° 53' E, 24.vii. 2001, Gerecke & Goldschmidt (14). Deposited in the NMW . Paratype: Madagascar: Antsiranana, Mt. d’Ambre Forest Reserve , stream at entrance gate, elev. 915 m, 12° 30' S, 49° 10' E, 13.xi.1986, J. T. & D. A. Polhemus (CL 2777) (1 USNM) .

Differential diagnosis. Distinguished from other members of the genus, except P. labrata , by the comparatively long maxillary palpi (palpus length/head width ca. 0.72) ( Fig. 71). Differentiated from P. labrata by the differently shaped last maxillary palpomere, the microreticulate, dull dorsum, and the differently shaped sides of the pronotum, among other characters. The aedeagus indicates a relationship with P. ankaratra ( Figs. 73, 74); the latter species has shorter palpi and dual-rimmed sides of the prothorax, among other differences.

Description. Size (length/width, mm) holotype: body (length to elytral apices) 1.46/0.64; head 0.25/0.42; pronotum 0.35/0.57, PA 0.48, PB 0.49; elytra 0.87 /0.64. Color dark brown, except head and pronotal disc piceous.

Head with eyes moderately large, in dorsal aspect ca. 8 convex facets in longest series. Ocelli indistinct, round small shining, each located at base of very shallow oblique interocular fovea. Frons effacedly microreticulate, dull, disc finely punctate, ca. 1xef on disc, finer anteriorly, interstices ca. 2–6xpd. Clypeus effacedly microreticulate, dull, punctures much finer than those of frons. Labrum dull, length subequal that of clypeus, apicomedially emarginate, anterior margin narrowly upturned; laterally fringed with short arcuate setae. Maxillary palpi moderately long, combined lengths of meres less than width of head (ratio ca. 21/29); ratios of meres 2–4 ca. 6/5/10. Mentum and submentum moderately coarsely punctulate, interstices effacedly microreticulate, weakly shining; genae moderately swollen.

Pronotum broad, anterior margin arcuate, ca. median 1/2 with narrow hyaline border. Anterior angles obtusangulate. Sides weakly rounded, widest at about midlength, weakly attenuate and sinuate behind middle, in lateral view margin with single rim. Posterior angle obtusangulate. Discal relief very finely sparsely punctate, punctures shallow, ca. 0.3xef, interstices effacedly microreticulate, dull, 3–6xpd; anterior and posterior impressions moderately deep, punctures much deeper and much larger than those on relief, some confluent, forming short transverse rows, each puncture with anterior margin extended posteriorly as narrow ridge, dividing puncture into a pair of two smaller punctures each of which ca. 1xef, short recumbent seta arising from posterior extreme of dividing ridge. Lacking impression at each posterior angle. Sculpture laterally subrugulose, dull.

Elytra weakly shining, attenuate posteriorly, sides arcuate, explanate margins moderately wide, distinct from shoulder for 3/4 of length, apices separately rounded. Ten-seriate punctate, not striate-impressed, punctures on disc small, round, ca. 2–3xef, interstices ca. 1xpd, anterior rim of each puncture with minute granule and minute recumbent seta, punctures becoming much smaller and shallower over posterior declivity; intervals ca. 2–3xpd, each with unilinear row of short recumbent setae very similar in size and spacing to setae of serial punctures, minute granule at base of some setae on disc.

Metaventrite with moderately deep, elongate oval impression in post 1/2; midlongitudinal carina between anterior extreme of groove and mesoventral intercoxal process. Metaventrite and abdominal ventrites 1–4 hydrofuge pubescent. Ventrites 5 and 6 elongate, effacedly microreticulate, shining. Ventrite 5 hydrofuge pubescent in anterior 1/5, posterior 1/2 with very sparse, long pubescence in transverse band. Ventrite 6 very sparsely pubescent in transverse band across posterior 1/2. Last ventrite very sparsely pubescent, free margin markedly arcuate; last tergite with moderately wide apicomedian notch, and bearing moderately long setae.

Legs short, femora moderately broad, metafemora width/metatarsus length ratio ca. 8/15; combined lengths of metatibia and metatarsus slightly greater than width of head (ratio ca. 35/29), ratio of lengths of metatibia/metatarsus ca. 20/15. Basal 3 protarsomeres, in male, with pad of suction setae. Female unknown.

Wings fully developed in holotype and paratype.

Aedeagus length ca. 0.48 mm (measured from base to tip of flagellum); gonopore bearing flagellum long, markedly sinuate, as long as main-piece; supporting distal piece in lateral view with three apical process, attaining slightly past midlength of gonopore bearing flagellum; main-piece in ventral view straight or nearly so, gradually increasing in width from base to apex, in lateral view markedly arcuate, rather thick, tapering apically; parameres very short, each with two setae ( Fig. 73).

Etymology. Named in reference to the moderately long (for Protozantaena ) maxillary palpi.

Distribution. Madagascar, currently known from two disjunct areas, northernmost and eastern central ( Fig. 101).