Mesovelia tenuia, Jehamalar & Chandra & Polhemus, 2019

Jehamalar, E. Eyarin, Chandra, Kailash & Polhemus, Dan A., 2019, Review of the Mesovelia horvathi species complex (Hemiptera: Gerromorpha: Mesoveliidae), with the description of seven new species from India, Zootaxa 4651 (3), pp. 471-496 : 491-495

Mesovelia tenuia sp. nov.

( Figs. 8 A–H)

Material examined. Holotype (apterous male): INDIA, TAMIL NADU, Kanyakumari District, Pallenvilai Village , 30 m a.s.l. , 8.30097 0 N, 77.21519 0 E, 8.vii.2014, Coll. E.E. Jehamalar & E. Hallings. Paratypes: 2 apt. ♂, 1 apt. ♀ same data as for holotype .

Repository. The type specimens are deposited in the CEL, ZSI, New Alipore, Kolkata, West Bengal, India. Holotype Reg. No. 8361/H15 and Paratypes Reg. No. 8362/H15.

Diagnosis. Mesovelia tenuia sp. nov. can be identified by the slender male paramere ( Fig. 8H ); the presence of the dark brown, almost straight spiniform setal tuft, usually with 3–6 spiniform setae, on male abdominal sternum VIII ( Fig. 8C ); and the flexor region of the fore and mid femora bearing a single subapical spine.

Description

Apterous male (holotype): ( Figs. 8A , C–H). Body length 2.11 (2.05–2.11, n=3); body width at metanotum 0.60 (0.57–0.60, n=3), body width at tergum IV 0.56 (0.55–0.56).

Colour. Brown; dorsum of body covered with minute brown setae; thorax and abdominal terga I–IV with brown marks; antenna brown to black; legs yellowish brown; femora of all legs subapically with brown hue; apex of tibia and first and last tarsomeres of all legs brown to black; claws, setiform spines on appendages black, spiniform setal tufts on abdominal sternum VIII dark brown.

Structural characters. Frontoclypeal region with 6–7 thick setae. Head length 0.32, head width across eyes 0.48; synthlipsis 0.20; eye length 0.19, eye width 0.11. Head in front of middle pair of trichobothria with few setae. Lengths of antennomeres I–IV 0.43, 0.34, 0.70, 0.63.

Pronotal length 0.18, width 0.52; mesonotal length 0.20, width 0.57; metanotal length 0.13, width 0.60. Lengths of leg segments: foreleg: femur 0.59, tibia 0.60, tarsomeres I–III 0.02, 0.06, 0.08; mid leg: femur 0.84, tibia 0.85, tarsomeres I–III 0.04, 0.16, 0.13; hind leg: femur 1.04, tibia 1.43, tarsomeres I–III 0.06, 0.25, 0.15. Widths of fore, mid, hind femora 0.11, 0.12, 0.13. Flexor region of fore and mid femora subapically with single spine; hind tibia sparsely clothed with medium sized spines; flexor region of second hind tarsomere with three almost evenly spaced thin, short setae.

Dorsal abdominal length 1.39; intersegmental suture between terga I–III visible; terga I–VIII 0.14, 0.16, 0.12, 0.15, 0.13, 0.16, 0.23, 0.23; sterna VI–VIII 0.14, 0.19, 0.12. Combined length of abdominal sterna VI–VII 0.33. Basal region of sternum VIII sublaterally with pair of dark brown spiniform setal tufts, each setal tuft with 4–6 spiniform setae arranged irregularly ( Fig. 8C ); sternum VIII midlaterally at the level of posterior margin with very small tubercle (more evident in alcohol after dissection), posterolaterally excavated; inner length of spiniform setal tuft on sternum VIII 0.06, basal width 0.03, width between two tufts 0.14; without any space between posterior margin of abdominal sternum VII and anterior margin of spiniform setal tuft. Terminalia: length of pygophore 0.24, anterior part of proctiger longer than bowl-shaped posterior part, clothed with long setae posteriorly, median lateral process long with acute tip, posterior part ventromedially convex, not excavated ( Fig. 8G ); paramere slightly broad basally, medially not twisted, apical part, long, curved ( Fig. 8H ), paramere when attached to pygophore apical part slightly curved and directed laterad in lateral view ( Fig. 8D ) and in dorsal view tip directed anterad ( Fig. 8E ).

Apterous female (paratype): ( Fig. 8B ). Colour: similar to apterous male. Body length 2.42, width across metanotum 0.68, width across tergum IV 0.92, head length 0.36, head width 0.50, eye length 0.18, eye width 0.13, synthlipsis 0.24; lengths of antennomeres I–IV 0.39, 0.33, 0.64, 0.67; pronotal length 0.17, width 0.56, mesonotal length 0.20, width 0.62, metanotal length 0.13, width 0.68. Lengths of leg segments: foreleg: femur 0.66, tibia 0.60, tarsomeres I–III 0.04, 0.06, 0.10; mid leg: femur 0.80, tibia 0.82, tarsomeres I–III 0.04, 0.18, 0.13; hind leg: femur 1.05, tibia 1.47, tarsomeres I–III 0.05, 0.27, 0.16. Widths of fore, mid, hind femora 0.10, 0.11, 0.13. Flexor region of fore and mid femora subapically with single spine.

Dorsal abdominal length 1.60, lengths of abdominal terga I–VIII, 0.16, 0.19, 0.17, 0.17, 0.16, 0.21, 0.23, 0.17; proctiger 0.10, dorsal gonoplac length 0.03, abdominal sterna V–VII, 0.14, 0.11, 0.17, abdominal length from sternum VIII to abdominal tip 0.50; combined length of abdominal sterna V–VII 0.41; maximum connexivum width at tergum V 0.21, ventral abdominal length from sternum V to abdominal tip 0.92.

Distribution. Presently known only from Kanyakumari District, Tamil Nadu, India ( Fig. 9D ).

Comparative notes. See under comparative notes of M. andamana .

Figures

FIGURES 8A–H. Mesovelia tenuia sp. nov. (A, C–H holotype; B, paratype): A, apterous male, dorsal view; B, apterous female, dorsal view; C, abdominal tip of apterous male, ventral view; D, genital capsule of apterous male, lateral view; E, same, dorsal view; F, eighth abdominal segment of apterous male, lateral view; G, proctiger of apterous male, ventral view; H, paramere of apterous male, lateral view (dmp—dorsomedian projection of pygophore; lex—lateral excavation; lp—lateral process; pa—paramere; pr—proctiger; py—pygophore).

FIGURES 9A–H. Distribution of Mesovelia horvathi species complex in India: A, Map of India; B, Meghalaya with M. bispinosa sp. nov. in red triangles, M. brevia sp. nov. in green square, M. isiasi sp. nov. in green cross; C, Meghalaya with M. dilatata sp. nov. in blue circles; D, Tamil Nadu with M. occulta sp. nov. in green circles, M. tenuia sp. nov. in pink square, M. brevia sp. nov. in green squares; E, Tamil Nadu with M. dilatata sp. nov. in blue circles; F, Andaman and Nicobar Islands with M. andamana sp. nov. in red circles.