Mesovelia isiasi, 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 : 488-491

Mesovelia isiasi sp. nov.

( Figs. 7 A–I)

Material examined. Holotype (apterous male): INDIA, MEGHALAYA, West Jaintia Hills District, Laskein Village, Paddy field, 1232 m a.s.l., 25.51083 0 N, 92.40692 0 E, 13.iii.2016 , Coll. E.E. Jehamalar. Paratypes: 2 apt. ♀, same locality data as for Holotype. 1 apt. ♂, Changpung Village, Umyurem River , 1245 m a.s.l., 25.48244 0 N, 92.33867 0 E, 13.iii.2016 ; 4 apt. ♂, Khliehtyrchi, Tyrchi falls , 1333 m a.s.l., 25.47192 0 N, 92.19108 0 E, 14.iii.2016 ; 1 apt. ♂, Mukhla Village, Pond , 1365 m a.s.l., 25.49744 0 N, 92.17175 0 E, 14.iii.2016 . East Khasi Hills District, 1 apt. ♀, Lyngiang Village, Stream , 1665 m a.s.l., 25.41767 0 N, 91.69792 0 E, 7.iii.2016 . East Garo Hills District, 1 mac. ♀, Warima Village, Simsang River , 268 m, 25.56668 0 N, 90.50925 0 E, 20.vi.2016 ; 1 apt. ♂, 1 apt. ♀, 1 nymph, Chidakgre Village, Rongdol Stream , 272 m a.s.l., 25.65672 0 N, 90.61028 0 E, 21.vi.2016 ; 1 apt. ♀, Darugre Village, Rongat River , 332 m a.s.l., 25.62215 0 N, 90.76859 0 E, 22.vi.2016 . West Garo Hills District, 1 apt. ♀, Adhangre Village, Pond , 36 m a.s.l., 25.23368 0 N, 90.17239 0 E, 11.vi.2016 ; 1 apt. ♀, Tikrikilla, Didak River , 35 m, 25.95449 0 N, 90.21321 0 E, 18.vi.2016 ; 3 apt. ♀, Chibongagre, Sum River , 38 m a.s.l., 25.67749 0 N, 90.02682 0 E, 15.vi.2016 ; 1 apt. ♀, Chochokia, Rajabala Nala , 32 m, 25.75136 0 N, 89.97665 0 E, 15.vi.2016 ; 1 mac. ♂, Rom Village, Rom River , 199 m a.s.l., 25.71478 0 N, 90.1299 0 E, 17.vi.2016 ; 1 apt. ♂, 2 mac. ♂, 1 apt. ♀, 1 mac. ♀, Churakathum Village , Pond, 185 m, 25.72503 0 N, 90.19274 0 E, 17.vi.2016 ; 1 apt. ♂, 1 mac. ♂, 2 apt. ♀, 1 nymph, Bolongkodak Village, Dabong River , 42 m a.s.l., 25.91517 0 N, 90.23245 0 E, 18.vi.2016 ; 1 apt. ♀, Ringmagre Village, Stream , 153 m, 25.741030 0 N, 90.089630 0 E, 18.vi.2016 . South West Garo Hills District, 1 mac-da ♀, Chilipara Vil- lage, 54 m a.s.l., 25.42378 0 N, 89.93026 0 E, 14.vi.2016 . South Garo Hills District, 1 mac-da ♀, Dabitampandam Village, Pond , 21 m a.s.l., 25.22096 0 N, 90.61389 0 E, 2.iii.2018 ; 1 apt. ♀, 1 mac-da ♀, Tarukol Village, Stream , 26 m a.s.l., 25.28074 0 N, 90.6477 0 E, 6.iii.2018 . West Khasi Hills District, 1 apt. ♀, Photumbah Village , Pond, 19.iii.2018 , 1465 m a.s.l., 25.61082 0 N, 91.37129 0 E. Ri-Bhoi District, 1 mac-da ♀, Wah Synon Village , Thana Stream, 23.iii. 2018, 370 m a.s.l., 25.94512 0 N, 91.62021 0 E. All specimens were collected by E. Eyarin Jehamalar.

Repository. The type specimens are deposited in the CEL, ZSI, New Alipore, Kolkata, West Bengal, India. Holotype Reg. No. 8339/H15 and Paratypes Reg. No. 8340/H15 to 8360/H15.

Etymology. This species is named after Dr. S. Isias, Principal, St. Alphonsa College of Arts and Science, Karungal, Tamil Nadu, for his support in arranging the field trips in Meghalaya.

Diagnosis. Mesovelia isiasi sp. nov. can be identified by the presence of a single spine on the flexor region of the fore femur and mostly one or rarely two spines on the flexor region of the mid femur only on one side; the relatively broad male paramere with a subapical constriction ( Fig. 7I ); and the presence of 8–13 spiniform setae in each of the tufts lying on either side of the midline on male abdominal sternum VIII ( Figs. 7D, E ).

Description. Apterous male (holotype): ( Figs. 7A , D–I). Body length 2.06 (1.99–2.12, n=5); body width at metanotum 0.57 (0.57–0.62, n=5), body width at tergum IV 0.59 (0.59–0.63, n=5).

Colour. Brown; dorsum of body covered with minute brown setae and with indistinct brown marks; antenna dark brown; legs yellowish brown; 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 to black.

Structural characters. Frontoclypeal region with 5 thick setae. Head length 0.29, head width across eyes 0.48; synthlipsis 0.21; eye length 0.16, eye width 0.12. Lengths of antennomeres I–IV 0.37, 0.26, 0.57, 0.67.

Pronotal length 0.21, width 0.54; mesonotal length 0.20, width 0.57; metanotal length 0.11, width 0.57. Lengths of leg segments: foreleg: femur 0.66, tibia 0.55, tarsomeres I–III 0.03, 0.05, 0.09; mid leg: femur 0.83, tibia 0.82, tarsomeres I–III 0.04, 0.14, 0.12; hind leg: femur 1.03, tibia 1.40, tarsomeres I–III 0.05, 0.22, 0.17. Widths of fore, mid, hind femora 0.11, 0.12, 0.13. Flexor region of fore and mid femora subapically with single spine, mid femur rarely with two spines; hind tibia sparsely clothed with medium sized spines; flexor region of second hind tarsomere with two widely spaced thin, short setae.

Dorsal abdominal length 1.26; intersegmental suture between terga I–III indistinct, terga I–VIII 0.12, 0.14, 0.13, 0.12, 0.11, 0.14, 0.21, 0.23; sterna V–VIII 0.13, 0.14, 0.16, 0.13. Combined length of abdominal sterna VI–VII 0.30. Basal region of sternum VIII sublaterally with pair of dark brown spiniform setal tufts, each setal tuft with 8–13 spiniform setae arranged irregularly ( Figs. 7D, E ); sternum VIII posterolaterally excavated, midlaterally at the level of posterior margin with very small tubercle (more evident in alcohol after dissection); inner length of spiniform setal tuft on sternum VIII 0.07, basal width 0.05, width between two tufts 0.12; 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 slightly longer than bowl-shaped posterior part, clothed with long setae posteriorly, median lateral process long with acute tip, posterior part ventromedially not excavated ( Fig. 7H ); paramere slightly broad basally, medially not twisted, apical part slender, medium sized and slightly curved ( Fig. 7I ), paramere when attached to pygophore apical part slightly curved and directed laterad in lateral view ( Fig. 7G ) and in dorsal view tip directed anterad ( Fig. 7F ).

Macropterous male (paratype): ( Fig. 7C ). Body length including hemelytra 2.15 (1.94–2.15, to abdominal tip, n=4); body width at humeral angle 0.64 (0.63–0.68, n=4).

Colour. Yellowish brown, posterior region of pronotum and metanotal elevation dark brown, membrane brown with large headed smoke white arrow mark ( Fig. 7C ), anal region of hemelytra below metanotal elevation with dark brown mark, inner basal region of hemelytra white, veins dark brown to black.

Structural characters. Notum length including metanotal elevation 0.65, length of anterior pronotal lobe 0.14, width 0.50, length of posterior pronotal lobe 0.31, width 0.64, length of mesoscutellum 0.13, length of metanotal elevation 0.11, humeral angle sinuated, lateral region of pronotum with few short black setae, posterior region of metanotal elevation with 5–6 medium sized setae; hemelytra with two closed basal cells, apical cell indistinct; hemelytral length 1.74, length to apex of corium 1.01, width across membrane 0.54, length of wing from abdominal tip to wing tip 0.17. Other characters similar to apterous male.

Apterous female (paratype): ( Fig. 7B ). Colour: similar to apterous male. Body length 2.23 (2.23–2.51, n=5), width across metanotum 0.63 (0.63–0.71, n=5), width across tergum IV 0.83 (0.78–0.90, n=5), head length 0.37, head width 0.48, eye length 0.16, eye width 0.11, synthlipsis 0.23; lengths of antennomeres I–IV 0.34, 0.28, 0.49, 0.63; pronotal length 0.17, width 0.55, mesonotal length 0.18, width 0.60, metanotal length 0.12, width 0.63. Lengths of leg segments: foreleg: femur 0.59, tibia 0.51, tarsomeres I–III 0.03, 0.05, 0.09; mid leg: femur 0.75, tibia 0.76, tarsomeres I–III 0.06, 0.15, 0.14; hind leg: femur 1.02, tibia 1.32, tarsomeres I–III 0.05, 0.20, 0.17. Widths of fore, mid, hind femora 0.10, 0.11, 0.14. Flexor region of fore and mid femora subapically mostly with single spine.

Dorsal abdominal length 1.41, combined length of abdominal terga I–III, 0.44, lengths of abdominal terga IV–VIII, 0.14, 0.14, 0.18, 0.21, 0.16; proctiger 0.09, dorsal gonoplac length 0.06, combined length of abdominal sterna VI–VII, 0.26, abdominal length from sternum VIII to abdominal tip 0.54; combined length of abdominal sterna V–VII 0.38; maximum connexivum width at tergum IV 0.19, ventral abdominal length from sternum V to abdominal tip 0.91.

Macropterous female (paratype). Body length including hemelytra 2.40 (2.23–2.51 to abdominal tip, n=5); body width at humeral angle 0.73 (0.69–0.77, n=5).

Colour. Similar to macropterous male.

Structural characters. Notum length including metanotal elevation 0.73, length of anterior pronotal lobe 0.15, width 0.54, length of posterior pronotal lobe 0.34, width 0.73, length of mesoscutellum 0.14, length of metanotal elevation 0.10, hemelytral length 1.85, length to apex of corium 1.11, width across membrane 0.57, length of wing from abdominal tip to wing tip 0.05. Other characters similar to macropterous male and apterous female.

Distribution. Presently known only from Meghalaya, India ( Fig. 9B ).

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

Figures

FIGURES 7A–I. Mesovelia isiasi sp. nov. (A, D–I holotype; B, C, paratype): A, apterous male, dorsal view; B, apterous female, dorsal view; C, macropterous male, dorsal view; D, abdominal apex of apterous male, ventral view; E, eighth abdominal segment of apterous male, lateral view; F, genital capsule of apterous male, dorsal view; G, genital capsule of apterous male, lateral view; H, proctiger of apterous male, ventral view; I, 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.