Agrilaxia (Agrilaxia) antennata, Bílý, Svatopluk, 2017

Bílý, Svatopluk, 2017, A study of the genus Agrilaxia Kerremans, 1903 from French Guiana (Coleoptera: Buprestidae: Anthaxiini), Zootaxa 4216 (1), pp. 65-72 : 68-69

Agrilaxia (Agrilaxia) antennata sp. nov.

( Figs 1, 6, 9 , 13 )

Type locality. French Guiana, Montaigne des Chevaux, Roura district, 4°44′56′′ N 52°26′28′′ W.

Type specimens. Holotype (male, NMPC): “ Guyane Française, M.gne [Montagne] des Chevaux, 4.viii.2012, S. Brûlé leg.” ; allotype (female, NMPC): “French Guyane, Mont Grand Matouri , 4°51′31′′N 52°20′54′′W, 3.x.2014, forest edge , SEAG team leg. // piège interception vitré”; paratypes: the same data as allotype (1 female, GCCI) ; “ Guyane Fr., Mont.[] Montagne ] de Chevaux, Com. de Roura, RN 2 PK22, 4°44′56′′ N 52°26′28′′ W, 75 m, 12.iv.2010, P.- H. Dalens leg.” (1 male, NMPC) .

Specimens not included among paratypes: remnants of 2 fragmentary specimens labelled: “ Guyane Fr., Res. N. des Nouragues, Camp Inselberg, ex larva, Comm. Régina, 3°37′N 53°12′W, 12.ix.2010, S. Brûlé, P.- H. Dalens & S. Fernandez leg.” (specimens mentioned as “sp. A” in Bílý & Brûlé, 2013).

Diagnosis. Small (4.5–5.3 mm), very slender, Agrilus -like ( Fig. 1 ); dorsal surface black with weak violet (male) or golden (female) lustre; frons of male green, that of female black-bronze; ventral surface of both sexes black with slight bronze lustre; antennae of male very long, reaching beyond humeral callosities when laid alongside, antennomeres 1–6 black with strong green lustre, antennomeres 7–11 yellow-brown; antennae of female short, hardly reaching midlength of lateral pronotal margins, black with green lustre; legs of male black with strong green lustre, those of female black.

Description of the male holotype. Head large, distinctly wider than pronotum, frons rather strongly convex with small, very shallow, postclypeal depression; frontoclypeus very narrow, anterior margin weakly emarginate; vertex nearly twice as wide as width of eye; eyes large, elliptical, projecting beyond outline of head; antennae very long, reaching beyond humeral callosities when laid alongside; scape 5 times as long as wide, slightly curved, pedicel ovoid, 1.5 times as long as wide; third antennomere narrow, slender, 2.3 times as long as wide, weakly triangular, antennomeres 4 and 5 axe-head shaped, 1.8 times as long as wide; 6th antennomere triangular, 1.5 times as long as wide, antennomeres 7–10 trapezoidal, nearly twice as long as wide, terminal antennomere rhomboid, 2.2 times as long as wide; sculpture consisting of basal microsculpture and small, polygonal, weakly developed cells without central grains.

Pronotum almost regularly convex, nearly parallel-sided, 1.2 times as wide as long with wide but shallow lateroposterior depressions; “agriloid” carina reaching posterior third of pronotal length, prescutellar pit small, shallow, almost indistinguishable; posterior pronotal angles acute; anterior margin with a wide, strongly developed median lobe, posterior margin nearly regularly curved with small prehumeral emarginations; sculpture consisting of small, dense polygonal cells without central grains. Scutellum very small, flat, subcordiform, about as long as wide.

Elytra matte, 3.2 times as long as wide, weakly convex but flattened at basal fifth, somewhat caudiform; lateral margins widely emarginate at midlength, subhumeral carina sharp, reaching elytral mid-length; humeral callosities small but well-developed, basal, transverse depression deep and wide reaching scutellum; apex of elytra with very fine serrations, elytral epipleura very narrow, not reaching apex; sculpture consisting of fine, silky microsculpture only.

Ventral surface lustrous with weakly developed polygonal sculpture, four apical ventrites of abdomen with fine longitudinal striae; both anal sternite and ventrite regularly rounded with finely serrate apical margins ( Fig. 6 ); prosternum anteriorly with deep groove and rolled up anterior margin (Fig. 27 in Bílý & Brûlé, 2013), prosternal process strongly convex with sharp, medial, longitudinal carina ( Fig. 9 ). Legs relatively long, slender, all tibiae straight becoming wider apically, tarsomere 1 of hind metatarsus as long as tarsomeres 2–5 together. Tarsal claws relatively long, only weakly hook-shaped, slightly enlarged at base.

Aedeagus ( Fig. 13 ) short, flattened, slightly spindle-shaped, median lobe obtusely pointed apically.

Measurement. Length: 4.5–5.3 mm (holotype 4.5 mm); width: 1.0– 1.2 mm (holotype 1.0 mm).

Sexual dimorphism. Except for the weak difference in the colouration (see above), the female differs from the male by the somewhat stouter body, less convex frons, very short, unicolorous antennae (reaching only mid-length of lateral pronotal margins when laid alongside), and significantly by the form of the prosternal process which is only weakly convex without the medial carina; anterior margin of prosternum of the same shape as in the male. The tarsomere 1 of the hind metatarsus of the female also relatively long but significantly shorter than the tarsomeres 2– 5.

Variability. No variability was observed except for the size and the slight sexual dichromatism.

Bionomy. Unknown.

Etymology. The specific epithet was derived from the Latin substantive “ antenna ” to stress the extraordinary length and the strange colouration of the male antennae.

Differential diagnosis. Agrilaxia (Agrilaxia) antennata sp. nov. can be easily identified due to the very slender, black body, rather strongly convex frons, unusual shape of the prosternum (especially in the male), very long hind metatarsus and the extremely long, bicolorous male antennae. All these characters are quite unusual in the subgen. Agrilaxia s. str. so this species cannot be confused with any species of Agrilaxia of a similar shape and colouration.

Distribution. French Guiana.

Figures

FIGURES 1 – 9. 1 — Agrilaxia (Agrilaxia) antennata sp. nov., holotype, 4.5 mm; 2 — A. (A.) angustiptera sp. nov., holotype, 6.1 mm; 3 — A. (A.) nigra sp. nov., holotype, 4.7 mm; 4 — A. (A.) nigropurpurea sp. nov., holotype, 7.1 mm. 5 – 8: anal tergites; 5 — A. (A.) angustiptera sp. nov., holotype; 6 — A. (A.) antennata sp. nov., holotype; 7 — A. (A.) nigra sp. nov., holotype; 8 — A. (A.) nigropurpurea sp. nov., holotype; 9 — prosternum, A. (A.) antennata sp. nov., holotype.

FIGURES 10 – 14. Aedeagi (schematically). 10 — Agrilaxia (Agrilaxia) nigropurpurea sp. nov., holotype (a—dorsal, blateral); 11 — A. (A.) angustiptera sp. nov., holotype; 12 — A. (A.) nigra sp. nov., holotype; 13 — A. (A.) antennata sp. nov., holotype; 14 — A. (A.) chrysifrons (Kerremans, 1896) (La Désirée).