Metrocoris morsei, Jehamalar, E. Eyarin & Chandra, Kailash, 2013

Jehamalar, E. Eyarin & Chandra, Kailash, 2013, Two new species of Metrocoris Mayr (Hemiptera: Heteroptera: Gerridae) from India, Zootaxa 3734 (1), pp. 63-71 : 64-66

Metrocoris morsei sp. nov.

( Figs. 1A–M )

Material examined. Holotype. ♂, (apt.): INDIA, Andaman & Nicobar Islands, Nicobar District, Great Nicobar Biosphere Reserve (GNBR), Nature Trail, 348 ft [106.1 m], N 07°00.202’, E 093°52.821’, 10.x.2010, Coll: E. Eyarin Jehamalar.

Paratypes. Same data as that of holotype 3 ♂, 4 ♀; GNBR, Laxmi Nagar, 367 ft [111.8 m], N 6°53.375’, E 93°53.178’, 25.x.2010, 1 ♀; Gandhi Nagar, 298 ft [90.8 m], N 6°50.215’, E 93°53.181’, 25.iii.2012, 2 ♂, 2 ♀; Nature Trail, 619 ft [188.6 m], N 6°59.954’, E 93°52.149’, 30.iii.2012, 6 ♂,7 ♀; East West Road 19th Km, Galathea tributary, 208 ft [63.3 m], N 6°58.831’, E 93°51.044’, 3.iv.2012, 1 ♂; Govind Nagar 10th Km, 351 ft [106.9 m], N 7°00.292’, E 93°53.017’, 9.iv.2012, 2 ♂, 4 ♀; Afra Bay, 113 ft [34.4 m], N 7°11.040’, E 93°44.184’, 15.iv.2012, 1 ♂; Macropterous form unknown. All materials were collected from streams of INDIA, Great Nicobar, GNBR, by E. Eyarin Jehamalar.

Diagnosis. The smaller body size, posterior margin of eyes almost reaching anterior mesopleura but not fully overlapping the proplura ( Fig. 1A, F ), slender fore femur, posterior median notch of male 8th tergum ( Fig. 1J ), falciform male paramere with pointed apex ( Fig. 1E ), medially convexed male proctiger ( Fig. 1L ), distinct colour pattern on thorax ( Fig. 1A ), swollen second mid tarsus ( Fig. 1B ), are the diagnostic features of Metrocoris morsei sp. nov.

Description. Apterous male (Holotype). (Figures A–G, J–L). Body length 3.26, range 2.85–3.5 (n=5), width (across mesoacetabula) 1.5, range 1.41–1.56 (n=5).

Colour. Yellow with prominent black stripes; interocular dark mark confined to anterior part of head, posterior part yellow; inner margin of eyes dark; basal 1/3 of first antennal segment yellow, remaining segments black; rostrum yellow, apical half of third and entire fourth segment piceous to black and shiny; body venter yellow, along the anterior portion of mesoacetabular suture with black stripe; pronotum with T-shaped stripe, central stripe very broad, lateral stripe united to sublateral and lateral stripe of mesonotum; mesonotum with thin median longitudinal stripe and broad sublateral stripe mostly connected to anterior transverse stripe of metanotum; longitudinal stripe of mesopleuron very short and confined only on anterior region ( Fig. 1F ), in some specimens sometimes reaching up to middle of mesopleura; mesoacetabular short stripe obscure; yellow part of metacetabulum not interrupted medially; fore, mid, and hind coxa, and trochanter yellow; fore femur black except base, yellow; mid and hind femur, tibia, and tarsus black except base of antero-lateral region of mid femur, yellowish brown; transverse stripe between mesonotum and metanotum angulated near middle anteriorly ( Fig. 1A ); abdomen fully black except abdominal segments six and seven, yellowish.

Structural characters. Head length 0.38, width 1.09, minimum interocular width 0.39; eye length 0.61, eye width 0.28, posterior eye width 0.43, eyes overlapping more than ¾ of propleura ( Fig. 1F ); antennal length I-IV 0.86, 0.57, 0.73, 0.59; rostral length III and IV together 0.4; head near to the anterior margin of eyes with few short setae; sub-apex of first antennal segment with a single setae little longer than few short erected setae of fourth antennal segment; rostrum surpassing the base of fore trochanter; first two rostral segments with piceous pubescence.

Pronotal length 0.28, width 1.02; lower margin of fore trochanter with three long setae and fringed with numerous setae; fore femur linear, slightly curved, base with a single long setae and two short setae, without any teeth underside apically; apical process of fore tibia prominent; second mid tarsus stout; pronotum slightly narrower than head; anterior and posterior margin of pronotum slightly sinuated; omphalium prominent and found on apex of reduced spindle shaped metasternum; Legs measurements: Range is given in parenthesis (n=5). Fore femur length 1.44 (1.16–1.53), width 0.2 (0.18–0.21); fore tibial length 1.23 (1.05–1.32); fore tarsus I 0.07 (0.06– 0.08); fore tarsus II 0.4 (0.34–0.44); mid femur length 3.86 (3.68–3.93), width 0.18 (0.18–0.19); mid tibia 2.85 (2.81–2.97); mid tarsus I 1.22 (1.2–1.28); mid tarsus II 0.23 (0.21–0.23); hind trochanter length 0.41 (0.39–0.44); hind femur length 3.78 (3.68–3.91), width 0.12 (0.11–0.12); hind tibia 2.01 (1.91–2.05); hind tarsus I 0.28 (0.26– 0.28), hind tarsus II 0.26 (0.25–0.27); hind femur slightly bend inwards; dorsum of abdomen clothed with short shiny golden hair; venter of abdomen densely clothed with pale yellow hairs; dorsum of dissected abdominal segment eight medially sinuated posteriorly ( Fig. 1J ); paramere falciform with acute apex ( Fig. 1E ); tergum VIII shiny without fringes of long hairs on posterior margin; length of abdominal tergite VIII 0.24, width 0.35.

Apterous female ( Figs. 1H, I ). Body length 3.32 range 3.22–3.37 (n=5), width (across mesoacetabula) 1.82 range 1.77–1.87 (n=5). Colour and structural characters similar to holotype with the following exceptions:

Lower margin of fore trochanter with seven long setae and basal fore femur with three long setae; seventh abdominal sternum of female longer than combined length of preceding abdominal sternites; tergum six, seven, eight half-yellowish; hind trochanter not hiding abdominal segment eight laterally.

Structural characters: Mean of five specimens are given and for legs range given in square brackets.

Head length 0.44, width 1.14, minimum interocular width 0.41; eye length 0.59, eye width 0.28, posterior eye width 0.41; antennal length I-IV 0.95, 0.55, 0.72, 0.59; rostral length III, IV 0.4, 0.17; pronotal length 0.26, width 1.11. Legs measurements: Fore femur length 1.34 [1.15–1.41], width 0.21 [0.19–0.21]; fore tibial length 1.25 [1.21–1.3]; fore tarsus I 0.08 [0.04–0.1]; fore tarsus II 0.41 [0.39–0.44]; mid femur length 3.86 [3.66–4.02], width 0.19 [0.18–0.19]; mid tibia 3.0 [2.94–3.09]; mid tarsus I 1.37 [1.31–1.42]; mid tarsus II 0.22 [0.19–0.22]; hind trochanter length 0.46 [0.43–0.47]; hind femur length 3.84 [3.64–4.0], width 0.12 [0.11–0.12]; hind tibia 2.17 [2.12–2.2]; hind tarsus I 0.30 [0.29–0.32]; hind tarsus II 0.27 [0.26–0.27]; combined length of abdominal sternites II–VI 0.33; sternite VI 0.10; sternite VII 0.44; sternite VIII 0.08.

Repository. The type specimens are deposited in the Central Entomological Laboratory, Zoological Survey of India, New Alipore, Kolkata. Holotype Reg. No. 3026/H15, Paratypes Reg. No. 3027/H15 to 3033/H15.

Etymology. This species is dedicated to Dr. John C. Morse, Emeritus Professor and Emeritus Director, Clemson University, South Carolina, USA, for teaching the first author about aquatic insects, for sending literatures, for encouragement, and timely and valuable help rendered by him.

Comparative notes. M. morsei sp. nov. does not match any of the known species groups, and thus forms a separate species group. The eye structure is close to M. hungerfordi den Boer, 1965 which has eyes fully covering the propleura; however, in M. morsei sp. nov. the eyes do not fully cover the propleura. Endosomal structures are similar to M. philippinensis species group, but other morphological characters do not match M. morsei sp. nov. Metrocoris morsei species group is characterized by small body size, linear fore femur with no notch or tooth on the venter, eighth tergum of male laterally hidden by hind trochanter, stout second mid tarsus, falciform paramere, sternum seven of female not covering the abdomen ventrally, and male abdominal segment eight cylindrical with a median notch posteriorly.

Figures

FIGURES 1 A – M. Metrocoris morsei sp. nov.: A, male, dorsal view; B, tip of male mid tarsus showing incrassated second segment; C, male endosoma showing sclerites; D, male genital capsule, lateral view; E, male left paramere; F, male, left lateral view; G, male endosoma, sheath not removed; H, Female abdomen, dorsal view; I, female genital segments, ventral view; J, male dissected eighth abdominal segment, dorsal view; K, same, left lateral view; L, male proctiger, dorsal view; M, female genitalia (aas—accessory apical sclerite; dls—dorsolateral sclerite of pygophore; ds—dorsal sclerite; du—ductus seminalis; ls 1 — left first lateral sclerite; ls 2 — left second lateral sclerite; pa—paramere; pds—proximal dorsal sclerite; pr—proctiger; py—pygophore; vs—ventral sclerite).