Mesovelia brevia, 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 : 476-478

Mesovelia brevia sp. nov.

( Figs. 2 A–H)

Material examined. Holotype (apterous ♂): INDIA, TAMIL NADU, Kanyakumari District, Parakai Village, Pond , 16 m a.s.l., 8.14049 0 N, 77.45403 0 E, 5.vii.2014, Coll. E.E. Jehamalar & E. Hallings. Paratypes: 1 mac-da ♂, same data as for holotype. 1 mac-da ♂, Suseentharam , 13 m a.s.l., 08.14786 0 N, 77.45742 0 E, 5.vii.2014, Coll. E.E. Jehamalar & E. Hallings ; 1 mac-da ♂, Nagercoil, Scott Christian College Pond , 60 m a.s.l., 8.18283 0 N, 77.40564 0 E, 8.iv.2008, Coll. E.E. Jehamalar. MEGHALAYA, East Garo Hills District, 1 mac. ♂, Warima Village, Simsang River , 268 m a.s.l., 25.56668 0 N, 90.50925 0 E, 20.vi.2016, Coll. E.E. Jehamalar.

Repository. The type specimens are deposited in the CEL, ZSI, New Alipore, Kolkata, West Bengal, India. Holotype Reg. No. 8307/H15 and Paratypes Reg. No. 8308/H15 to 8311/H15.

Etymology. The name brevia is derived from the Latin adjective “brevis” which means short, referring to the very short apical part of the male paramere.

Diagnosis. Mesovelia brevia sp. nov. can be identified by the peculiarly shaped, very short (0.02) and subtriangular apical part of the male paramere ( Fig. 2H ); the presence of a pair of black, mostly erect spiniform setal tufts, usually with 6 and rarely with 5 or 7 spiniform setae, on male abdominal sternum VIII ( Fig. 2C ); the macropterous form with a large white arrow-shaped mark on hemelytral membrane ( Fig. 2B ); and the flexor region on the femora of all legs lacking spines.

Description. Apterous male (holotype): ( Figs. 2A, C, E, F ). Body length 1.45, body width at metanotum 0.39, body width at tergum IV 0.37.

Colour. Brown; dorsum of body covered with minute brown setae, pigmentation of dorsum of body indistinct; frontoclypeal region dark brown antenna brown, eyes brown to black; apex of tibia, first and last tarsomeres of all legs brown to black, except basal half of third fore tarsomere yellow; claws, setiform spines on appendages, spiniform setal tufts on abdominal sternum VIII black; setae on proctiger brown.

Structural characters. Frontoclypeal region with 5–6 thick setae. Head length 0.31, head width across eyes 0.32; synthlipsis 0.14; eye length 0.12, eye width 0.08. Head near inner margin of eye with 5 setae arranged longitudinally. Lengths of antennomeres I–IV 0.26, 0.21, 0.44, 0.44.

Pronotal length 0.12, width 0.35; mesonotal length 0.13, width 0.36; metanotal length 0.09, width 0.39. Lengths of leg segments: foreleg: femur 0.42, tibia 0.38, tarsomeres I–III 0.03, 0.04, 0.06; mid leg: femur 0.53, tibia 0.53, tarsomeres I–III 0.03, 0.08, 0.08; hind leg: femur 0.67, tibia 0.91, tarsomeres I–III 0.04, 0.13, 0.09. Widths of fore, mid, hind femora 0.07, 0.08, 0.08. Flexor region of femora of all legs lacking spines; flexor region of second hind tarsomere with two widely spaced thin, short setae.

Length of abdominal tergum 0.81; intersegmental suture between abdominal terga I–III not visible medially, combined length of terga I–III (fused) 0.25, terga IV–VIII 0.08, 0.07, 0.09, 0.12, 0.16; sterna VI–VIII 0.09, 0.11, 0.09. Combined length of abdominal sterna VI–VII 0.20. Basal region of sternum VIII sublaterally with pair of black spiniform setal tufts, each setal tuft with six spiniform setae ( Fig. 2C ); sternum VIII 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 0.02, basal width 0.04, width between two tufts 0.08; without any space between posterior margin of abdominal sternum VII and anterior margin of spiniform setal tuft. Terminalia: length of pygophore 0.16, 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. 2G ); paramere broad basally, D-shaped, medially not twisted, apical part, short, slightly curved ( Fig. 2H ), paramere when attached to pygophore with apical part slightly curved and directed anterolaterad in lateral view ( Fig. 2E ), apex directed anterad in dorsal view ( Fig. 2F ).

Macropterous male (paratype): ( Figs. 2B, D, G, H ). Body length including hemelytra 2.08 (1.42–1.80 to abdominal tip, n=3); body width at humeral angle 0.61 (0.47–0.61, n=4).

Colour. Yellowish brown, posterior region of pronotum and mesoscutellum dark brown, membrane brown with largeheaded white arrow mark ( Fig. 2B ), anal vein black, costal vein and corial region brown, corial apex brown to black.

Structural characters. Posterolateral margin adjacent to ocelli with minute downwardly directed black setae; dorsal thoracic length including metanotal elevation 0.60; length of anterior pronotal lobe 0.12, width 0.45; length of posterior pronotal lobe 0.28, width 0.61; length of mesoscutellum 0.10, length of metanotal elevation 0.09; humeral angle sinuated, lateral region of pronotum and posterior region of mesoscutellum and metanotal elevation with a few short black setae; hemelytra with three closed cells, basal two elongate, apical cell very small, enclosed by thick brown to black veins, membrane brown with large headed white mark; hemelytral length 1.43, length to vein tip 0.80, width across membrane 0.43, length of wing from abdominal tip to wing tip 0.14. Other characters similar to apterous male.

Female: Unknown.

Distribution. Presently known from the Kanyakumari District of Tamil Nadu and the East Garo Hills District of Meghalaya, India ( Figs. 9B, D ).

Comparative notes. Superficially, M. brevia sp. nov. is closely related to M. dilatata sp. nov., M. occulta sp. nov. and M. horvathi in terms of general appearance, and by the absence of spines on the flexor region of the fore and mid femora, but clearly differs from M. dilatata sp. nov. and M. occulta sp. nov. in the number of spines in the spiniform setal tufts of abdominal sternum VIII. In M. brevia sp. nov. the setal tufts usually contain 6 spiniform setae each ( Fig. 2C ), but in M. dilatata sp. nov. each setal tuft is composed of 8–9 spiniform setae ( Fig. 3G ) whereas in M. occulta sp. nov. the setal tuft contains only 3–5 spiniform setae ( Fig. 4F ). The lateral process on the male proctiger in M. brevia sp. nov. is boat-shaped with a pointed tip ( Fig. 2G ), whereas in M. dilatata sp. nov. it is oblique with blunt tip ( Fig. 3I ), and in M. occulta sp. nov. it is oblique, and abruptly tapered apically ( Fig. 4H ). The apical part of the male paramere in lateral view is short in M. brevia sp. nov. ( Figs. 2E, H ), but long in M. dilatata sp. nov. ( Fig. 3J ), M. horvathi ( Fig. 1E ) and M. occulta sp. nov. ( Fig. 4K ). The basal part of the male paramere is highly dilated in M. dilatata sp. nov. ( Fig. 3J ), but only moderately dilated in M. brevia sp. nov. ( Figs. 2E, H ), M. horvathi ( Fig. 1E ) and M. occulta sp. nov. ( Fig. 4K ). The gap between the spiniform setal tufts on the abdominal sternum VIII is narrow (0.08–0.10) in M. brevia sp. nov., versus twice as wide (0.16) in M. occulta sp. nov. and M. dilatata sp. nov. (0.19).

Figures

FIGURES 1A–F. Mesovelia horvathi Lundblad apterous male: A, habitus, dorsal view; B, dorsal view of legs; C, eighth abdominal segment, lateral view; D, genital capsule, dorsal view; E, same, lateral view; F, fore femur, ventral view (dmp—dorsomedian projection of pygophore; lex—lateral excavation; lp—lateral process; pa—paramere; pr—proctiger; py—pygophore).

FIGURES 2A–H. Mesovelia brevia sp. nov. (A, C, E, F, holotype; B, D, G, H, paratype): A, apterous male, dorsal view; B, macropterous male, dorsal view; C, eighth abdominal segment of apterous male, ventrolateral view; D, eighth abdominal segment of macropterous male, lateral view; E, genital capsule of apterous male, lateral view; F, same, dorsal view; G, proctiger of macropterous male with forewing membrane broken off, ventral view; H, paramere of macropterous male with forewing membrane broken off, lateral view (dmp—dorsomedian projection of pygophore; lex—lateral excavation; lp—lateral process; pa—paramere; pr—proctiger; py—pygophore).

FIGURES 3A–K. Mesovelia dilatata sp. nov. (A, E, F, H, J, holotype; B, C, D, G, I, K, paratype): A, apterous male, dorsal view; B, apterous female, dorsal view; C, macropterous female with forewing membrane broken off, dorsal view; D, abdominal tip of apterous male, ventral view; E, genital capsule of apterous male, lateral view; F, same, dorsal view; G, eighth abdominal segment of apterous male, ventrolateral view; H, eighth abdominal segment of apterous male, lateral view; I, proctiger of apterous male, ventral view; J, paramere of apterous male, lateral view; K, terminalia of apterous female, lateral view (ab9— ninth abdominal segment; dmp—dorsomedian projection of pygophore; go1—first gonapophyses; go2—second gonapophyses; gp—gonoplac; lex—lateral excavation; lp—lateral process; pa—paramere; pr—proctiger; py—pygophore).

FIGURES 4A–K. Mesovelia occulta sp. nov. (A, E, G–K holotype; B, C, D, F, paratype): A, apterous male, dorsal view; B, apterous female, dorsal view; C, macropterous female with forewing membrane broken off, dorsal view; D, abdominal apex of apterous female, ventral view; E, fore leg of apterous male, ventral view; F, eighth abdominal segment of apterous male, ventrolateral view; G, eighth abdominal segment of apterous male, lateral view; H, proctiger of apterous male, ventral view; I, genital capsule of apterous male, dorsal view; J, same, lateral view; K, 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.