Thysanarthria brincki Hebauer, 2001

Fikáček, Martin & Liu, Hsing-Che, 2019, A review of Thysanarthria with description of seven new species and comments on its relationship to Chaetarthria (Hydrophilidae: Chaetarthriini), Acta Entomologica Musei Nationalis Pragae 59 (1), pp. 229-252 : 240

Thysanarthria brincki Hebauer, 2001

( Figs 5 A–E, 11 )

Thysanarthria brincki Hebauer, 2001: 395

Type material examined. HOLOTYPE: ♂ ( MZLU), ʻCeylon, E. Prov. / Madura Oya / 15 mls NNW Bibile / 13.III.62 Loc. 138 // near river // Lund University / Ceylon Expedition 1962 / Brinck-Andersson- / Cederholm // MZLU / Type no. / 3119:1 // Photo 2017 / by MZLU // MZLU / 2017 / 510’.

Redescription. Body length 1.6 mm, maximum body width 1.0 mm. Head and labrum black, pronotum and elytra uniformly yellowish; legs reddish to yellowish. Head with strong mesh-like microsculpture on interstices; punctation sparse, each puncture bearing pointed seta. Eyes separated by 2.8× the width of one eye in dorsal view. Pronotum with sparse setiferous punctation similar to that on head; interstices with mesh-like microsculpture. Elytra with 10 striae sharply impressed anteromedially (near scutellar shield) where neither striae nor serial punctures are visible; intervals weakly convex at midlength and near apex; interval punctation sparse, setiferous; interstices without microsculpture. Aedeagus slightly over 0.5 mm long (basal part of phallobase broken in the holotype). Phallobase weakly and gradually narrowing from base of parameres to base, weakly arcuately bent in lateral view, slightly longer than parameres. Paremeres wide, c. of same width throughout, arcuately bent, apex rectangularly widened, with a denticle apicolaterally. Median lobe pointed apically, widening to the level of gonopore, more basally slightly constricted again, subapically with a pair of triangular projections; apex not reaching the level of apex of parameres; gonopore transversely oval, situated below the base of paired projections.

Differential diagnosis. Thysanarthria brincki is easy to recognize by the unusual shape of the parameral apices which are widely rectangular with a small anterolateral spine; in this character it slightly resembles T. cardamona sp. nov. but differs from it in parameres c. of the same width throughout (compared to the parameres wide basally and strongly constricted in distal third in T. cardamona .

Biology. Unknown.

Distribution. Only known from the type locality in Sri Lanka ( HEBAUER 2001).

Figures

Fig. 5. Male genitalia of Thysanarthria species, holotypes.A–E – T.brincki Hebauer, 2001 (A–C – whole aedeagus in dorsal, lateral and ventral view; D–E – detail of median lobe and parameres in dorsal and ventral view); F–J – T. cardamona sp. nov. (F–H – whole aedeagus in dorsal, lateral and ventral view; I–J – detail of median lobe and parameres in dorsal and ventral view); K–M – T. bengalensis Hebauer, 2001 (K – photo of the aedeagus before re-mounting; L – whole aedeagus in ventral view; M – whole aedeagus in lateral view).

Fig. 11. Distribution of Thysanarthria and American Chaetarthria in Asia (A–B) and Near East (C), and examples of habitats of Thysanarthria (D–F). Localities: D – India, Madhya Pradesh, Bhadhua Chora stream ca. 10 km E of Matkuli Jhir, habitat of T. ceylonensis Hebauer, 2001; E – Republic of South Africa, Western Cape, 8 km NEE of Stanford, habitat of T. atriceps (Régimber, 1903), collecting spot marked by an arrow; F–G – Taiwan, Wufeng distr., 4.3 km SEE of Chaoyang University of Technology, habitat of T. chui sp. nov. (G – detail of sandy shore with one alive beetle). Photo D by M. Jäch, photo E by M. Fikáček, F–G by H.-C. Liu.