Agrilaxia (Agrilaxia) biformis, Bílý, Svatopluk, 2015

Bílý, Svatopluk, 2015, A study on the genus Agrilaxia Kerremans, 1903 from Venezuela (Coleoptera: Buprestidae: Buprestinae: Anthaxiini), Zootaxa 4039 (1), pp. 173-182 : 175-177

Agrilaxia (Agrilaxia) biformis sp. nov.

( Figs. 5, 6 , 11, 13, 14 )

Type locality: Venezuela, Provincía Falcón, 24 km NW Guamacho, 1.5 km S Tocópero, 11°29.067′N 69°15.250′W, 95 m.

Type specimens. Holotype (male, NMPC): “ Venezuela (Falcón): 24 km NW Guamacho, 1.5 km S Tocópero, 1°29.067′N 69° 15.250′W, 95 m 14.vii.2008, S. Gottwald leg.”; allotype (female, NMPC): the same data; paratypes: the same data (3 males, MHCB, SGCB, NMPC); “ Venezuela, Edo. Falcón, 3.5 km NW Maicillal, Cerro Togogo, 11′13′39.8′′N 68°53′10.2′′W, 64 m, 2–14.vii.2008, M. Hornburg leg.” (3 males, 4 females, MHCB, MIZA); “ Venezuela, Edo. Falcón, nr. Maicillal, Cerro Togogo, 11′12′36.4′′N 68°50′26.0′′W, 99 m, 6.vii.2008, from Pithecellobium sp., M. Hornburg leg.” (1 male, MHCB); “ Venezuela, Edo. Falcón, nr. Guamacho, 11°29′03.9′′N 69°15′15.4′′W, 95 m, 14.vii.2008, M. Hornburg leg.” (1 male, 1 female, MHCB); “ Venezuela, Edo. Aragua, NP Henri Pittier, bei Puerto Colombia, 23.viii.2001, M. Hornburg leg.” (1 male, MHCB).

Diagnosis. Medium-sized (4.3–6.1 mm), convex, elongate, slightly wedge-shaped, matt with silky lustre; male ( Fig. 5 ): head bronze, frons weakly darkened at middle, frontoclypeus bright bronze, pronotum, red-bronze with red lustre along lateral margins, elytra yellow-brown with bronze humeral callosities, tips and suture; scutellum, antennae and legs bronze; female ( Fig. 6 ): frons and scutellum red-bronze, pronotum bronze, elytra dark bronze with green reflections along lateral margins; antennae and legs black-bronze; ventral surface of both sexes redbronze, lateral margins of abdominal ventrites in female with green lustre; entire body completely asetose.

Description of the male holotype. Head large, wider than anterior pronotal margin; anterior margin of frontoclypeus widely, shallowly emarginate, frons flat to weakly depressed, with shallow, almost triangular, postclypeal depression; vertex medially weakly depressed, 1.3 times as wide as width of eye; eyes large, widely reniform, very slightly projecting beyond outline of head; antennae relatively short, slightly overlapping midlength of lateral pronotal margins when laid alongside; scape slender, very long, weakly curved in apical third, 6 times as long as wide, pedicel ovoid, 1.5 times as long as wide; third antennomere subcylindrical, almost twice as long as wide; antennomeres 4–10 obtusely triangular to trapezoidal, about as long as wide, terminal antennomere rhomboid, 1.4 times as long as wide; sculpture consisting of small, dense, polygonal and oval cells with large central grains.

Pronotum convex, 1.3 times as wide as long, with shallow, rather wide lateroposterior depressions; anterior margin deeply bisinuate, medial lobe large, wide, strongly projecting anteriorly, posterior margin weakly bisinuate; lateral margins slightly S-shaped, maximum pronotal width at anterior third; posterior angles acute; prescutellar pit small, basal callosities weak; “agriloid” carina small, short, weakly developed, almost imperceptible; sculpture homogeneous, consisting of small, dense, polygonal cells with small central grains. Scutellum small, pentagonal, slightly wider than long.

Elytra slightly convex, 2.6 times as long as wide, with 3 very weak, longitudinal ribs which are almost imperceptible on apical half; interstices with very weak rows of shallow, hardly visible punctures; humeral callosities relatively large, transverse, basal depression wide, deep, reaching scutellum; subhumeral carina obtuse, short, not reaching midlength of lateral margins; posterior third of lateral margins weakly arched, very finely serrate at very apex; sculpture consisting of very fine microsculpture and small, fine punctures fused transversely into fine rugae.

Ventral surface lustrous, with fine ocelliform sculpture, anterior margin of prosternum straight with shallow, transverse groove, anterior edge of prosternum somewhat raised. Anal tergite sharply serrate with small, medial notch ( Fig. 13 ), anal sternite obtusely rounded with fine lateral serrations. Legs slender, meso- and metatibiae almost straight without inner serration. Tarsal claws very small, slightly hook-shaped, weakly enlarged at base.

Aedeagus ( Fig. 11 ) rather long, spindle-shaped, flattened, dorsoventrally slightly bent; parameres sharply pointed apically, median lobe obtusely pointed.

Measurements. Length: 4.3–6.1 mm (holotype 4.5 mm); width: 1.1–1.7 mm (holotype 1.2 mm).

Sexual dimorphism. Very strongly developed; the female ( Fig. 6 ) differs from the male (except for the colouration–see above) by the much wider vertex (twice as wide as width of eye), larger and stouter body and by the finely serrate anal tergite without the medial notch ( Fig. 14 ).

Variability. One male paratype possesses bright-red tinge at lateroposterior, pronotal depressions and very fine, narrow, red medial stripe at the anterior pronotal third; one female paratype possesses small, reddish, circumscutellar field and also narrow red, medial stripe at the anterior third of pronotum.

Differential diagnosis. The male of Agrilaxia (A.) biformis sp. nov. has a similar colouration to that of A. (A.) boliviana Cobos, 1972 ( Bolivia) , A. (A.) acuminata Cobos, 1972 ( Peru) and with the female of A. (A.) panamensis Cobos, 1972 ( Panama) . From A. (A.) boliviana it differs by the large head which is wider than anterior pronotal margin, large eyes, much narrower vertex, finer pronotal sculpture, very small prescutellar pit, unicolorous, bronze pronotum (with two narrow, blue, lateral stripes in A. (A.) boliviana ) and by the shape of male genitalia (more parallel in A. (A.) boliviana —see Fig. 22 in Cobos 1972). From A. (A.) acuminata it differs also by the larger, wider head with weakly grooved frons and large eyes, finer pronotal sculpture, red-bronze scutellum (bright green in A. (A.) acuminata ), elytral pattern (elytra almost completely yellow in A. (A.) acuminata ) and by the somewhat slender aedeagus (for that of A. (A.) acuminata —see Fig. 20 in Cobos 1972). The female of A. (A.) biformis sp. nov.

differs from the females of both species by the unicolorous, bronze body but it strongly resembles by the colouration and general body-shape A. (A.) krombeini Cobos, 1972 ( Panama) female of which is unknown. This species differs from A. (A.) biformis sp. nov. by the convex frons, parallel-sided pronotum with very sharp posterior angles, deeper and wider lateroposterior pronotal depressions, more extensive ocelliform sculpture and by the somewhat caudiform elytra. Agrilaxia (A.) biformis sp. nov. differs from A. (A.) panamensis (male unknown) by the posteriorly regularly arched elytral margins (distinctly caudiform elytra in A. (A.) panamensis ), narrow vertex, wide head and by the unicolorous pronotum (with three blue stripes in A. (A.) panamensis ); the yellow elytral pattern of the latter is limited only to the humeral part of elytra.

Etymology. The specific epithet is derived from the Latin prefix “ bi -” (twice, double) and the substantive “ forma ” (form) to stress the strong sexual dichromatism.

Bionomy. One paratype (Cerro Togogo) was found on leaves of Pithecellobium dulce (Mimosaceae) . This tree is well-known as a very attractive plant for a number of xylophagous beetles and it is also the host plant of many species but it was not confirmed as the host plant of A. (A.) biformis sp. nov..

Distribution. Ven ez uel a.

Note. Many species of the genus Agrilaxia exhibit more or less strong sexual dichromatism but in the case of A. (A.) biformis sp. nov. it is the extreme example where both sexes are completely different in colouration ( Figs. 5 vs. 6).

Figures

FIGURES 1 – 9. 1 — Agrilaxia (Agrilaxia) balloui Fisher, 1942, female (Colombia, Valledupar), 5.0 mm; 2 — A. (A.) costaricensis Obenberger, 1922, female (Venezuela, El Limon), 7.5 mm; 3 — A. (A.) glabra Bílý & Brûlé, 2013, female (Venezuela, Nubia), 5.4 mm; 4 — A. (A.) simillima (Cobos, 1972), male (Venezuela, Aragua), 6.0 mm; 5 — A. (A.) biformis sp. nov., holotype, 4.5 mm; 6 — A. (A.) biformis sp. nov., allotype, 4.9 mm; 7 — A. (A.) michaeli sp. nov., holotype, 4.4 mm; 8 — A. (A.) stephani sp. nov., holotype, 4.5 mm; 9 — A. (A.) venezuelana sp. nov., holotype, 7.3 mm.

FIGURES 10 – 15 (not to scale). Figs. 10 – 12: aedeagi. 10 — Agrilaxia (Agrilaxia) balloui Fisher, 1942 (Venezuela, El Valle); 11 — A. (A.) biformis sp. nov., holotype; 12 — A. (A.) venezuelana sp. nov., holotype; Figs. 13 – 15: anal tergites. 13 — A. (A.) biformis sp. nov., male, paratype; 14 — A. (A.) biformis sp. nov., female, paratype; 15 — A. (A.) venezuelana sp. nov., holotype.