Gomesius indicus, Ghate & Mathew, 2018

Ghate, H. V. & Mathew, Mirjoy, 2018, First record of the genus Gomesius (Hemiptera: Heteroptera: Reduviidae: Emesinae) from India, with description of a new species, Zootaxa 4461 (3), pp. 421-428 : 422-424

Gomesius indicus sp. nov.

( Figs. 1–25 )

Diagnosis. Gomesius indicus sp. nov. can be differentiated from other congeners by a combination of the following characters: eyes large, reaching ventral outline of head in lateral view; mesonotum with a pair of shining dark brown, round and slightly sunken areas near posterior border; presence of four pairs of tubercles - one pair on each of abdominal sternites four to seven, lack of lobate extensions on connexival margins; laterally and ventrally fully visible eighth abdominal sternite.

Description. Male. Measurements (in mm). Total length to the tip of abdomen 23. Head length 1.5; length of anteocular portion 0.75; length of postocular portion 0.35; eye diameter measured horizontally in lateral view 0.60; lengths of antennal segments: I: 10.00; II: 6.50; III: 3.25; IV: 4.25; labium: total length 1.82; lengths of labial segments: II (first visible): 0.50; III: 0.50; IV: 0.82; total length of pronotum 3.12; mesonotum 2.50; legs (lengths): fore coxa 4.00; femur 5.30; tibia 1.30; tarsus (including claw) 2.00; middle coxa 0.87; femur 15.0; tibia 17.0; tarsus (including claw) 0.70; hind coxa 0.95; femur 20.5; tibia 25.0; tarsus (including claw) 0.81. Pygophore length 1.60; length from base to parameres 1.50; maximum width at base of parameres 0.87.

Color and integument: Body surface partly dull partly subshining. Body dark brown with a few ochraceous spots or blotches, without any conspicuous pattern; legs more ochraceous with dark brown spots ( Fig. 8, 9, 11 ). Head with a horizontal dark brown stripe across eye laterally ( Fig. 2 ), dorsally with brown blotch centrally, on either side of median pale line of setae, in between eyes ( Fig. 4, 6 ). Antenna dark brown, with irregular ochraceous marking ( Fig. 3 ); second segment mostly ochraceous with a basal, apical and few middle dark annulations, third and fourth segments almost entirely ochraceous, with faint basal and apical brownish spots.

Pronotum darker, with few irregular ochraceous blotches; mesonotum brown, base with a pair of round, dark brown, slightly sunken and shining areas ( Figs. 7 ). Scutellum and metanotum dark brown. Fore coxae and femora with fine dark brown elongate spots on external as well as internal surfaces, those on coxae mostly hidden under setae; similar elongate dark spots on mid and hind femora in apical portion only ( Fig. 1 ). Mid femora brown with ochraceous markings while hind femora pale brown with indistinct markings; mid tibiae more ochraceous than femora with a few dark brown blotches; hind tibia very pale brown except in apical region where colour is dark; tarsus dark. Forewing pale brown with fuscous blotches or bands along major veins ( Fig. 10 ).

Abdominal tergites brownish with indistinct, median, longitudinal ochraceous line on first four or five segments; sixth to seventh tergites with two median parallel dark brown longitudinal lines. Underside of head, thoracic and abdominal sternites brown; sternites VII, VIII and pygophore very dark brown; median, longitudinal broad ochraceous band present on abdominal sternites VI–VIII and pygophore, this band very prominent on seventh and eighth sternites as well as on pygophore ( Figs. 11 , 17 ). Spiracles surrounded by whitish annulus.

Vestiture: Entire body clothed with very fine, adpressed, colorless or golden setae. Head dorsally covered with three lines of pale setae; antennal setae mostly fine, short, adpressed, along with few slightly longer erect setae, Pronotum with dense cover of setae, with a median band with more dense setae. Mesonotum with thick, longitudinal lines of setae giving appearance of median and a pair of lateral pale lines. Scutellum and metanotum also with two rows of pale setae. Sternum and abdominal sternites with a cover of fine setae. All legs covered with moderately dense fine setae. Hind tibia with scattered, small, dark spine-like setae.

Structure: Head elongate, more or less fusiform in lateral view, gently rounded dorsally, more or less flat ventrally; anteocular about twice longer than postocular portion, the latter with sides converging posteriorly in dorsal and lateral views. Interocular transverse sulcus or furrow distinct in dorsal view but less so in lateral view, conspicuously backwardly curved but not attaining level of posterior border of eyes, with a pair of small tubercles dorsomedially on posterior border of transverse sulcus ( Figs. 2, 4, 6 ). Eyes large and reaching ventral margin of head. Labium with second (first visible) and third (second visible) segments moderately stout, fourth (third visible) slender and pointed at tip; overall labium straight, not bent between first and second visible segments. First two visible segments of labium subequal in length, third longest; distal tip of first visible segment of labium is in vertical line with antenniferous tubercles above, second visible segment reaches beyond level of anterior border of eye while last segment reaches level of fore coxae. Antennae inserted dorsally at middle of anteocular portion ( Fig. 2 ). Pronotum elongate, subcylindrical, with anterior and posterior one third broader than median narrowed part, with very small but distinct hind lobe, its posterior border not covering mesonotum ( Fig. 5, 6 ). Scutellum and metanotum without spines. Posterior border of prosternum distinctly emarginated ( Fig. 12, 13 ). Forelegs moderately stout and long; fore coxae slender than fore femora; fore femora slightly constricted near middle and widened again distally and then almost subparallel. Each fore femur with posteroventral and anteroventral series of spiniform setae and one stout process on outer surface, slightly in front of penicillate process. Posteroventral series beginning at a distance from base of femur equal to one-third of total length of the article, composed of one basal, elongate, penicillate process followed by a large number of slender spiniform setae inserted on short, wartlike bases ( Figs. 8, 9 ). Anteroventral series beginning distinctly apicad of basal process of posteroventral series, not interrupted but strongly curved at base, consisting exclusively of smaller, slender spiniform setae. Tibia short and stout, about one-fourth length of femur; ventrally with one series of short, adpressed, spiniform setae. Tarsus not segmented, longer than tibia and gently curved. One simple, very small claw only ( Figs. 1 , 8, 9 ). Mid and hind legs long; hind femora very long, surpassing apex of abdomen. Claws long and slender. Forewings narrow, not attaining apex of abdomen, leaving about 2.5 mm length of abdomen exposed, with venation as shown in Fig.10 . Abdomen elongate, parallel-sided, more or less widened posteriorly, connexivum moderately broad; posterior angles of connexivum of sixth and seventh segment angularly produced backward ( Fig. 11 ). Abdominal sternites IV–VII with a pair of sublateral protuberances or tubercles near anterior border, those on fifth and sixth prominent than others; distance between two tubercles of same segment about 0.8 mm while distance between tubercles of consecutive segments about 2.0 mm ( Fig. 15 ). Tergite VII rounded at posterior border; sternite VIII visible fully from lateral and ventral side ( Figs. 17, 18 ). Segment VIII and pygophore slightly compressed laterally.

Male genitalia. Pygophore elongate, somewhat pear shaped in lateral view ( Fig. 18 ), almost rectangular in dorsal ( Figs. 16, 19 ) and ventral views ( Figs. 17, 20 ); dorsal bridge very short; posterior border of pygophore with broad, apically notably emarginated process, tips of this emargination well-rounded ( Figs. 20, 21 ). Parameres curved, densely setose and only moderately thickened in middle part ( Fig. 25 ).Phallus symmetrical. Articulatory apparatus stout. Phallosoma short, subcylindrical, its distal opening somewhat wide. Endosoma with numerous small, dark sclerites dispersed all over ( Figs. 22–24 ).

Female unknown at present.

Type material. Holotype: male, INDIA, Goa, Mollem , xi.2016, leg. Mirjoy ; presently in the private collection of H.V. Ghate, Modern College, and will be deposited in the Zoological Survey of India, Western Regional Station, Pune.

Etymology. The specific name is the Latin adjective indicus , - a, - um (meaning ‘Indian’, ‘from India’), referring to the fact that this is the first species of Gomesius documented from India.

Figures

FIGURES 1–7. Gomesius indicus sp. nov., male holotype. 1, anterior half of body, lateral view; 2, head, lateral view; 3, antenna, first segment; 4, head, dorsal view; 5, pronotum, lateral view; 6, head and pronotum, dorsal view; 7, mesonotum, scutellum and basal portion of forewings, dorsal view. Scale bars: 1 mm.

FIGURES 8–15. Gomesius indicus sp. nov., male holotype. 8, foreleg, lateral view (scale bar 1 mm); 9, fore femur (except basal portion), tibia and tarsus; 10, forewing, dorsal view; 11–14, ventral views; 11, whole body, (scale bar 2 mm); 12, thoracic sternum; 13, prosternum; 14, meso- and metasterna; 15, abdominal sternites, ventrolateral view (scale bar 1 mm), white pointers showing sternal tubercles.

FIGURES 16–25. Gomesius indicus sp. nov., male holotype, genitalia. 16–20, pygophore and parameres; 16, in situ, dorsal view; 17, same, ventral view (scale bar 1 mm); 18, same, lateral view; 19, detached, dorsal view; 20, same, ventral view; 21, apex of pygophore; 22, phallus, inverted, lateral view (scale bar 0.5 mm), 23, phallus, everted, lateral view; 24, endosoma; 25, parameres (outer view on left, inner view on right).