Exocelina pseudofume Shaverdo & Balke

Shaverdo, Helena, Sagata, Katayo & Balke, Michael, 2018, Introduction of the Exocelinacasuarina-group, with a key to its representatives and descriptions of 19 new species from New Guinea (Coleoptera, Dytiscidae, Copelatinae), ZooKeys 803, pp. 7-70 : 32

17. Exocelina pseudofume Shaverdo & Balke sp. n. Figs 7, 32

Exocelina fume _New_Guinea_MB 4169: Toussaint et al. 2015: supplementary figs S1-S2, table S3, and information S5-S6.

Type locality.

Papua New Guinea: Madang Province, Wannang, 05°15.458'S, 145°02.389'E, 270 m a.s.l.

Type material studied.

Holotype: male "Papua New Guinea: Madang, Wannang, 270m 31.x.2008, 05.15.458S 145.02.389E, Posman, (PNG187)" (ZSM). Paratypes: 6 males, 1 female with the same label as the holotype, one of males additionally with "M.Balke 4169" [green] (NHMW, ZSM).

Description.

Body size and form: Beetle medium-sized: TL-H 3.3-3.6 mm, TL 3.6-3.95 mm, MW 1.8-2.0 mm (holotype: TL-H 3.3 mm, TL 3.6 mm, MW 1.9 mm), with oblong-oval habitus.

Coloration: Reddish to reddish brown, with head and pronotum paler. Head yellowish red to reddish brown, with small darker areas posterior to eyes. Pronotum yellowish red to reddish brown, darker (to brown) on disc. Elytra reddish brown to brown, sometimes with narrow yellowish or reddish sutural lines. Head appendages and legs yellowish red, legs distally darker, especially metathoracic legs (Fig. 7). All specimens are slightly teneral, therefore, the species coloration might be more darker.

Surface sculpture: Shiny dorsally. Head with rather dense punctation (spaces between punctures 1-2 times size of punctures), evidently finer and sparser anteriorly; diameter of punctures smaller than diameter of cells of microreticulation or equal to it. Pronotum and elytra with very distinct punctation, sparser and slightly finer than on head. Pronotum and elytra with weakly impressed microreticulation. Head with microreticulation stronger. Metaventrite and metacoxae distinctly microreticulate, metacoxal plates with longitudinal strioles and transverse wrinkles. Abdominal ventrites with distinct microreticulation, strioles, and very fine sparse punctation.

Structures: Pronotum without lateral bead. Base of prosternum and neck of prosternal process with distinct ridge, slightly rounded anteriorly. Blade of prosternal process lanceolate, relatively narrow, slightly convex, with distinct lateral bead and few setae. Abdominal ventrite 6 rounded.

Male: Antennae simple (Fig. 7). Protarsomere 4 with anterolateral seta thin, long, smaller than more laterally situated large setae, slightly curved downwards. Protarsomere 5 long and narrow, with anterior band of ca 40 and posterior row of 10 relatively long setae (Fig. 32D). Median lobe in lateral view slightly curved, its apex strongly bent downwards, with visible angle on dorsal side; in ventral view, almost subparallel and distally narrowed to truncate apex. Paramere slightly concave on dorsal side and with long, dense, thin setae, situated along dorsal margin: subdistal setae denser than setae in middle and proximal parts (Fig. 32 A–C). Abdominal ventrite 6 with 5-8 lateral striae on each side.

Female: Without evident differences in external morphology from males, except for not modified protarsi and abdominal ventrite 6 without striae.

Affinities.

Exocelina pseudofume sp. n. is similar to E. messeri and E. keki sp. n. but it has distinctly broader and more oval habitus, shinier dorsal surface due to weaker microreticulation, as well as median lobe of different shape: thicker, with apex broader and curved downwards, with visible angle on dorsal side in lateral view. The shape of median lobe is similar to that of E. fume .

Distribution.

Papua New Guinea: Madang (Fig. 50).

Etymology.

The species is named " pseudofume " because shape of its median lobe remains that of E. fume . The name is a noun in the nominative singular standing in apposition.