Thysanarthria ceylonensis Hebauer 2001
Creators: name: Fikáček, Martin
name: Liu, Hsing-Che
Publisher: name: Zenodo
Year: 2019
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Hydrophilidae
Thysanarthria
Thysanarthria ceylonensis

description: Thysanarthria ceylonensis Hebauer, 2001
(Figs 6 K–O, 11)
Thysanarthria ceylonensis Hebauer, 2001: 396
Type material examined. HOLOTYPE: ♂ (MZLU), SRI LANKA: NORTHERN PROVINCE: ʻCeylon, N. Prov. / Kudattanai / 6 mls SE Point Pedro / 13.II.62, Loc. 70 // At pond in semi- / desert // Lund University / Ceylon Expedition 1962 / Brinck-Andersson- / Cederholm // MZLU / Type no. / 3120:1 // Photo 2017 / by MZLU // MZLU / 2017 / 511’.
Additional material examined. INDIA: MADHYA PRADESH: 1 ♂, 2 specimens (NHMW, NMPC): River Denwa, ca. 8 km SSE Matkuli, Satpura Range, 400 m, 28.ii.2008, lgt. M. Jäch, S. & P. Sharma; 1 ♀ (NHMW): Hoshangabad Distr., Bandrabhan, ca. 60 km SSE Bhopal, ca. 5 km NE Hoshangabad, River Narmada, 280 m, 23.‒24.ii.2008, lgt. M. Jäch, S. & P. Sharma; 1 spec. (NHWM): Chhindwara Distr., Bhadhua Chora (stream), ca. 10 km E Matkuli near Mahul Jhir, 400 m, 28.ii.2008, lgt. M. Jäch, S. & P.Sharma; 1♀ (NHMW): Hoshangabad Distr., Dhobighat Nala (stream), ca. 2 km SE Pachmarhi,Saphura Range, 900 m, 27.ii.2008, lgt. M. Jäch, S. & P. Sharma.
Redescription. Body length 1.5–1.7 mm (holotype 1.5 mm), maximum body width 0.9–1.0 mm (holotype 0.9 mm). Head and labrum black and pronotum uniformly yellowish; elytra yellowish with slightly darker lateral parts; legs reddish to yellowish. Head with strong microsculpture on interstices; punctation sparse, each puncture bearing pointed seta. Eyes separated by 3.5× the width of one eye in dorsal view. Pronotum with sparse setiferous punctation similar to that on head; interstices without microsculpture. Elytra with 10 striae sharply impressed except 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 (Figs 6 K–O) 0.4 mm long. Phallobase not much wider at base of parameres than more basally, only indistinctly narrowed at midlength; arcuate in lateral view. Paremere moderately wide basally, slightly narrowing towards apex, apex widely angulate. Median lobe widely bottle-shaped, rounded apically, without paired subapical projections; apex not reaching level of parameral apices; gonopore rounded, situated far from apex.
Differential diagnosis. Thysanarthria ceylonensis resembles T. bengalensis, T. brincki and H. saurahana in having strong mesh-like microsculpture on the head, but it can be easily distinguished from all these species as well as from all other Thysanarthria by a very characteristic aedeagus.
Biology. Specimens from Madhya Pradesh were collected at the sides of small to large rivers with stony banks (e.g., Fig. 11D) but precise microhabitat is not known (M. A. Jäch, pers. comm.).
Distribution. Described from Sri Lanka (HEBAUER 2001) but here recorded from central India (Madhya Pradesh), hence the species is likely widespread in the Indian Peninsula.
description: Published as part of 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), pp. 229-252 in Acta Entomologica Musei Nationalis Pragae 59 (1) on pages 240-242, DOI: 10.2478/aemnp-2019-0020, http://zenodo.org/record/4488918