Nematopus persuasus, Brailovsky, 2015

Brailovsky, Harry, 2015, The genus Nematopus (Hemiptera: Heteroptera: Coreidae) of French Guiana with a description of one new species, Acta Entomologica Musei Nationalis Pragae (suppl.) 55 (1), pp. 39-45 : 40-44

Nematopus persuasus sp. nov.

( Figs 2–4 , 9 )

Type material. HOLOTYPE: ♁, FRENCH GUIANA: Savane Roche (inselberg) de la Haute-Koursibo, light trap, 31.x.2013, P. H. Dalens ( UNAM) . PARATYPE: 1 ♀, same data as male holotype ( UNAM).

Description. Male (holotype). Dorsal coloration. Head shiny yellow; ocelli pale red; eyes dark red; antennal segments I to III pale castaneous orange with reddish marks, segment IV pale castaneous orange; pronotal disk yellow, punctures castaneous; anterolateral and posterolateral margins and humeral angles yellow with olive-brown to pale green sheen, and punctures dark reddish brown; scutellum shiny yellow, punctures castaneous orange; anterior third of clavus shiny dark brown, posterior third shiny orange; corium shiny dark brown, with costal margin, veins and apical margin yellow, suffused with olive-brown to olive-green marks; inner third of endocorium shiny orange; hemelytral membrane yellow; connexival segments III to VI yellow, VII dark reddish brown with upper margin yellow; dorsal abdominal segments shiny dark yellow with lateral margins dark brownish orange.

Ventral coloration. Ground color shiny yellow; apex of rostral segment IV brown; mesopleura with large ovoid shiny castaneous brown spot; middle and hind acetabula with one creamy yellow callosity; coxae, trochanters, and femora shiny yellow, with pale green sheen; apex of femora with two pale reddish brown spots lateral to midline; posterior third of hind femur with spines and tubercles reddish brown; tibiae and tarsi pale yellowish orange, with pale green sheen; abdominal sterna III to VI with two rows of oval creamy yellow callosities lateral to middle line, one callosity located near anterior margin and the other near posterior margin; sternite VII with only one anterior callosity; middle third of abdominal sterna IV to VI with slender longitudinal creamy yellow callosity; genital capsule dark brown.

Structure. Elongated specimens, medium-sized, less than 20 mm, lean, not flattened, with connexivum exposed. Head wider than long; tylus enlarged, almost globose, projecting anteriorly from antenniferous tubercle, longer than juga which are reduced to short lateral flanges; preocular space without tubercle; antenniferous tubercle wide, unarmed, reaching base of antennal segment I; antennae long, slender; antennal segment I stoutest, II and III cylindrical, IV fusiform; postocular tubercle rounded, tiny, exposed, forming smooth curve with eye; head ventrally and behind each eye with small protuberance; rostrum reaching anterior third of mesosternum; rostral segment I short, not extending beyond middle third of eye.

Pronotum wider than long; calli barely raised above pronotal disk; calli, anterior margin and basal third of anterolateral margins broken up into a number of small tubercles; humeral angles expanded into medium-sized spine directed outward, clearly upward, and apically subacute; triangular process of posterolateral angle elongate, reaching anterior margin of scutellum, and apically almost rounded; mesosternum lacking sulcation; metasternal scent gland ostiole placed relatively close to lateral margin of metapleuron ( Fig. 2 ). Scutellum transversely striate.

Legs. Trochanters unarmed; fore and middle femora armed with two stout subapical spines; hind femur incrassate in both sexes, but much more so in male, dorsally smooth and ventrally with double row of small irregular tubercles, two pairs of stout subapical spines and one slender medium-sized spine near middle third; hind tibiae sulcate, inner face with irregular tiny granules and one small cone-shaped spine near middle third; hind tibiae not armed distally.

Abdomen. Posterior angle of connexival segments IV to VII with short spine conspicuously acute; abdominal spiracles situated nearer anterior than lateral margin. Posteroventral margin of genital capsule with mesial keel, apically split in two long branches resembling winged expansions pointing to the sides and leaving concavity between them; keel delimited laterally by two short, strong projections which distally become sharper and slightly spiniform ( Figs 3–4 ).

Measurements (mm). Total body length 16.40. Head length 1.48; width across eyes 2.20; interocular width 1.20; interocellar width 0.40; preocular length 1.00; length of antennal segments: I – 3.24; II – 2.68; III – 2.40; IV – 5.60. Pronotal length 2.92; width across humeral angles 4.92. Scutellar length 2.32; width 1.84.

Female. Habitus and color similar to male holotype. Pronotum with collar and anterior margin olive-brown; connexival segments VIII and IX black with anterior margin castaneous orange; hind femur yellow with pale green sheen and posterior third brown; dorsal abdominal segments VIII and IX dark yellowish orange; outer margin of metapleura and pleural margins of abdominal sterna III to VII tinged with green; gonocoxae I dark brown; paratergite VIII yellow with upper and inner border dark brown; paratergite IX dark brown with upper border yellow. Hind tibiae unarmed.

Measurements (mm). Total body length 18.55. Head length 1.52; width across eyes 2.40; interocular width 1.30; interocellar width 0.46; preocular length 1.02; length of antennal segments: I – 3.00; II – 2.64; III – 2.48; IV – 5.64. Pronotal length 3.60; width across humeral angles 5.40. Scutellar length 2.72; width 2.36.

Differential diagnosis. This new species is related to N. spinulus Brailovsky & Barrera, 2003 in having the humeral angles strongly expanded ( Figs 9–10 ). In N. spinulus the humeral angles are directed outward and apically rounded, the triangular processes of posterolateral angles of pronotum are small, broad, and apically subacute, and the color of pronotal disk pale orange with punctures chestnut orange, whereas in N. persuasus sp. nov., the humeral angles are strongly expanded with a medium-sized spine directed outward, clearly upward and apically subacute, the triangular processes are elongate, apically almost rounded, and the pronotal disk is yellow, punctures castaneous and anterolateral and posterolateral margins, and humeral angles yellow with olive-green to pale green sheen ( Figs 1–2 ). The male genital capsule differs in the general shape ( Figs 3–6 ).

Etymology. The species name is the Latin adjective persuasus (a, um), meaning persuasive, convincing, believable.

Distribution. Known only from French Guiana.

Figures

Figs 1‒6. Nematopus spp. 1‒2 ‒ pronotum: 1 ‒ N. spinulus Brailovsky & Barrera, 2003; 2 ‒ N. persuasus sp. nov. 3‒6 ‒ male genital capsule: 3‒4 ‒ N. persuasus sp. nov. (3 ‒ caudal view, 4 ‒ lateral view). 5‒6 ‒ N. spinulus Brailovsky & Barrera, 2003 (5 ‒ caudal view, 6 ‒ lateral view).

Figs 7–10. Dorsal view of Nematopus spp. 7 – N. indus (Linnaeus, 1758). 8 – N. nervosus Laporte, 1832. 9 – N. persuasus sp. nov. 10 – N. spinulus Brailovsky & Barrera, 2003.