Thysanarthria championi ( Knisch, 1924 )

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 : 242-243

Thysanarthria championi ( Knisch, 1924)

( Figs 2 H–M,b, 3 A,C–F, 7 A–J, 11 )

Chaetarthria championi Knisch, 1924b: 40 .

Thysanarthria championi: ORCHYMONT (1926a: 195 , transfer to Thysanarthria ); ORCHYMONT (1926b:242, transfer to Thysanarthria explained in more detail, comparison with T. atriceps ); HANSEN (1999: 105, catalogue); HEBAUER (2001:398, redescription and update of distribution).

Chaetarthriomorphus sulcatus Chiesa, 1967: 276 , syn. nov.

Thysanarthria sulcata: HANSEN (1991: 126 , transfer to Thysanarthria ); HANSEN (1999: 105, catalogue).All other records of this species refer to different species, see under T. persica sp. nov. and T. wadicola sp. nov.

Type material examined. Chaetarthria championi . LECTOTYPE (here designated): ♂ ( BMNH), INDIA: UTTARKHAND: ʻRanikhet / Kumaon / India, H. G. C. // G. C. Champion / Brit. Mus. / 1924-42. // Chaetarthria / championi / Knisch // det. Knisch / W. E. Z. 1924ʼ. PARALECTOTYPES: 1 spec. ( BMNH), same label data as the lectotype; 1 spec. ( BMNH): ʻW. Almora / Kumaon U.P. / India, H. G. C. // G. C. Champion / Brit. Mus. / 1924-42. // Chaetarthria / championi / Knisch // Knisch det. 1922 / Chaetarthria / championiʼ; 1 spec. ( BMNH): ʻW. Almora / Kumaon / India, H. G. C. // G. C. Champion / Brit. Mus. / 1924-42. // Chaetarthria / championi / Knisch // Knisch det. 1922 / Chaetarthria / championiʼ

Chaetarthriomorphus sulcatus : LECTOTYPE (here designated): ♂ ( HNHM): AFGHANISTAN: ʻNO.Afghan.1953 / J. Klapperich // Nuristan, 1200 m / Bashgultal, 20.IV. // Paratypus 1964 / Chaetarthriomorphus / sulcatus / Chiesa // CHAETARTHRIOMORPHUS / sulcatus / CHIESA / CHIESA DET. // AEDEAGUS / DRAWN BY / P. D. PERKINS’.

Additional material examined. NEPAL: 1 ♂ ( NMPC), S Ganesh Himal village,near Kali Sundhara Bazar, 700 m, 24.–25.v.1996,lgt.Ahrens, Kulbe & Rulik; 1 ♂, 3 specimens ( SMNS): Narayani, Sauraha, bank of Rapti River, light trap, 180, 84.49695, 27.56667, 2000-04-18, A. Weigel; 1 ♂ ( SMNS):same label data but lgt.A. Skale. INDIA: UTTARANCHAL: 1 ♂, 22 specimens ( NMPC): ca. 13 km NW of Nainital, Khaira [= Khairna] bridge, near river, at light, 900 m, 13.–17.vii.2003, lgt. Z. Kejval & M. Trýzna. ARUNACHAL PRADESH: 1 ♂, 8 specimens ( NMPC): 8 km S Jamiri-Sesa vicinity, 350 m, 4.–26.v.2006, lgt. P.Pacholatko. CHINA: YUNNAN: 1 ♂, 2 spec. ( NHMW): 100 km W of Kunming, Diaolin Nature Reserve, 22.v.–2. vi.1993, lgt.E. Jendek & O.Šauša; 1♂, 2 spec. ( NMPC):Tongbiguan vill., near river, at light, 1340 m, 24°36.7ʹN 97°39.4ʹE, 24.–26.vi.2018, lgt. J. Hájek &J.Růžička. MYANMAR: 1♂, 6 specimens ( NHMW): Mandalay, ca. 50 km NW Kalaw,Myitsona river, 450 m, 25.x.1998,lgt.Schillhammer.

Redescription. Body length 1.5–2.0 mm (holotype 1.9 mm), maximum body width 1.0– 1.1 mm (holotype 1.0 mm). Head and labrum black; pronotum yellowish with vaguely delimited darker central spot of variable extent or in some specimens (incl. holotype) completely dark brown; elytra yellowish with darkened elytral striae, or with darker lateral parts, or uniformly brown (incl. in holotype); legs yellowish to brown. Head with weak microsculpture on interstices; punctation sparse, each puncture bearing pointed seta. Eyes separated by 3.1× 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 (but darker spots may be present, resembling real punctures); intervals weakly convex at midlength and near apex; interval punctation sparse, setiferous; interstices without microsculpture. Aedeagus ( Figs 7 A–J) c. 0.5 mm long. Phallobase not much wider at base of parameres than more basally, only indistinctly narrowed at midlength; arcuate in lateral view. Paremere wide basally, gradually narrowing towards apex, outer face nearly continuously arcuate, slightly bisinuate in apical fourth, apex bluntly pointed; mesal face with short cuticular asperities (visible in cleaned aedeagus only, Fig. 7E ). Median lobe widely bottle-shaped, without paired subapical projections; apex nearly reaching level of parameral apices, membranous, rounded in relaxed position ( Figs 7D , I–J), with a pair of backwards directed lobes when fully everted (not usually visible); gonopore rounded, situated subapically.

Differential diagnosis. Thysanarthria championi resembles T. bifida sp. nov., T. trifida sp. nov., and T. chui sp. nov. in the general morphology of the aedeagus and the basally wide parameres arcuately narrowing into widely to narrowly rounded apex; of these T. bifida and T. trifida can be distinguished by the presence of a pair of subapical projections on the median lobe (absent in T. championi ); T. chui lacks these lobes, but its parameres are relatively shorter and more abruptly narrowed apically, projecting into rounded lobes. Thysanarthria championi is one of four species co-occurring in Himalaya, along with T. madurensis , T. saurahana sp. nov., and T. siamensis ; it can be easily distinguished from all of them by the morphology of male genitalia.

Comments on synonymy. The above type specimen of Chaetarthriomorphus sulcatus is the only found in the Klapperich collection in HNHM. It is largely damaged, with prothorax and one elytron completely missing. However, the abdomen and male genitalia are present, and the morphology of the aedeagus corresponds completely with that of the lectotype of T. championi . The elytron is paler, not dark brown, which further supports the fact that C. sulcatus cannot be conspecific with the specimens from southern Iran (described here as T. persica sp. nov.) and the northern Arabian Peninsula (described here as T. wadicola sp. nov.) as erroneously reported by HEBAUER (1997) and FIKÁČEK et al. (2010). Following these facts, the examined specimen is designated as the lectotype, and Chaetarthriomorphus sulcatus is here placed in synonymy with Chaetarthria championi .

Biology. Part of the examined specimens was collected at light on river banks, no more information is available.

Distribution. The species is widely distributed in the foothills of the Himalaya Mts. and the adjacent mountain systems in eastern Afghanistan (Hindukush Mts.), southwestern China (Yunnan), and Myanmar. The specimens listed by HEBAUER (2001) from Laos are females and hence their identity cannot be confirmed.

Figures

Fig. 2. Morphological differences among Thysanarthria and principal groups of Chaetarthria. A–Z – male genitalia and surrounding sclerites; a–e – details of elytral pubescence. A – Chaetarthria similis Wollaston, 1864; B–G, c – Chaetarthria seminulum (Herbst, 1797); H–M, b – Thysanarthria championi (Knisch, 1924); N–S, d – Chaetarthria panda Orchymont, 1939; T–Z, e – Chaetarthria malickyi Hebauer, 1995; a – Thysanarthria atriceps (Régimbart, 1903). A–D, K–M, Q–S, X–Z – aedeagus in dorsal, lateral and ventral view; E, J, P, V – male sternite 9; F, H, N, T – male sternite 8; G, I, O, U – male tergite 8. Figures a–e are all to the same scale.

Fig. 3. Morphology of Thysanarthria. A – mentum and maxillary palps; B – meso- and metaventrite and meso- and metafemora; C – head and prothorax in ventral view; D – antenna; E – ultimate maxillary palpomere with basal peg-like setae; F – metatarsus; G – ventral view with gelatinous substrance on the base of abdomen; H – detail of abdomen with gelatinous substance in the cavity on ventrites 1–2. A, C–F – Thysanarthria championi (Knisch, 1924); B, G–H – T. atriceps (Régimbart, 1903).

Fig. 7. Male genitalia of Thysanarthria championi (Knisch, 1924).A–E – lectotype of Chaetarthria championi Knisch, 1924 (A–C – whole aedeagus in dorsal, lateral and ventral view; D – detail of median lobe and parameres in dorsal view; E – same after KOH treatment, with fully everted internal sac). F–J – lectotype of Chaetarthriomorphus sulcatus Chiesa, 1967 (F–H – whole aedeagus in dorsal, lateral and ventral view; I–J – details of parameres and median lobe in dorsal and ventral 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.