Tituboea purchati, Bezděk, 2012

Bezděk, Jan, 2012, Tituboea purcharti sp. nov., the first representative of Clytrini from Socotra Island (Coleoptera: Chrysomelidae: Cryptocephalinae), Acta Entomologica Musei Nationalis Pragae 52, pp. 395-401 : 396-400

Tituboea purchati sp. nov.

( Figs. 1–2 , 6, 8–10)

Type locality. Yemen, Socotra Island, Al Haghier Mts., wadi Madar, 12°33.2´N, 54°00.4´E.

Type material. HOLOTYPE: ♂, ‘ YEMEN, Socotra Island / Al Haghier Mts. / wadi Madar, 1180-1230 m / 12°33.2´N, 54°00.4´E, / L. Purchart leg., 12-14.xi.2010 [w, p]’ ( NMPC). PARATYPES: 2 ♀♀, same data as holotype ( JBCB); 12 ♂♂ 6 ♀♀, ‘ Yemen, Soqotra Is. , QAARIAH / vill. env., 28.xi.2003, N 12°38´/ 05´´ E 54°12´39´´, 11 m (GPS) / leg. P. Kabátek [w, p] // YEMEN – SOQOTRA / 2003 / Expedition; Jan Farkač, / Petr Kabátek & David Král [w, p]’ ( NMPC, 1 ♂ in JBCB, 1 ♂ in BMNH, 1 ♂ in NHMB). The specimens are provided with additional printed red labels: ‘ HOLOTYPUS [or PARATYPUS] / Tituboea / purcharti sp. nov. / det. J. Bezděk 2011 ’.

Description. Body length: ♂♂ 7.3–9.9 mm (holotype 9.6 mm); ♀♀ 8.3–10.3 mm.

Male (holotype, Fig. 1 ). Body subcylindrical, parallel, glabrous, lustrous. Head including mouthparts orange, tips of mandibles darkened. Antennomeres I–IV orange, antennomeres V–XI black with pale bases. Pronotum orange with infuscate middle part of posterior margin. Scutellum black. Elytra orange, behind middle with black transverse fascia with irregular margins, near suture slightly widened and bent posteriorly. Legs orange, claws black with pale bases. Prosternum orange, mesosternum orange in the middle, laterally black, metasternum and abdomen including pygidium black.

Head. Labrum short, transverse, almost impunctate, with several long pale setae along anterior margin, anterior angles widely rounded, anterior margin shallowly incised. Head distinctly constricted behind eyes. Anterior part of head lustrous, almost impunctate and glabrous, aside from antennal insertions with small shallow impressions; clypeus widely shallowly triangularly incised, with short fine pale setae along anterior margin. Frons wide, 2.5 times as wide as diameter of eye, with transverse shallow impression in midpart, densely and coarsely punctured, covered with dense short setae (slightly longer near eyes). Vertex lustrous, densely covered with fine small punctures and short pale setae. Antennomere I club-shaped; antennomeres II and III very small, cylindrical; antennomere IV small, triangular; antennae distinctly serrated from antennomere V.

Pronotum transverse, 1.71 times as wide as long, widest at two thirds, moderately convex, covered with extremely fine, almost invisible punctures, lustrous. Anterior half of lateral margins convergent, straight, posterior half widely rounded, anterior margin slightly concave, posterior margin nearly straight, distinctly thickened in scutellar area.Anterior angles rectangular with rounded tip, posterior ones almost imperceptible, widely rounded. All angles bearing setigerous pore with long pale seta. Lateral margins narrowly bordered, anterior margin bordered only laterally, border of posterior margin narrow laterally, broader at scutellar thickening. Scutellum triangular with sharply rounded apex, base covered with fine punctures and pale setae, apex lustrous, impunctate, scutellar apex elevated upon level of elytra.

Elytra subcylindrical, 1.56 times as long as wide at humeral part, glabrous, lustrous, densely covered with small fine confused punctures. Basal margin narrowly bordered, lateral margin thinly bordered in anterior third, widely bordered in middle third and disappearing in posterior third. Epipleura glabrous, basally wide, gradually thinner posteriorly, disappearing in midlenght of elytra. In lateral view, lateral margin of elytra widely concave.

Tarsi short and relatively slender. Protarsomere I short, subtriangular, 1.33 times as long as broad, 0.58 times as long as two following tarsomeres combined, protarsomere II subtriangular, almost as wide as long, protarsomere III very deeply incised ( Fig. 6 ).

Ventral part. Propleurae glabrous. Prosternal projection not visible between procoxae. Abdomen flattened, last ventrite bent downwards.

Male genitalia. Aedeagus ( Fig. 2 ) slender, flat, with distinctly prolonged apex.

Female. Frons broader, pronotum slightly broader and elytra slightly longer than in males (see Variability). Tarsi slightly narrower than in males.Abdomen robust, convex, last ventrite with small round impression in middle. Spermatheca C-shaped with relatively sharp inner angle, spermathecal duct very long with numerous coils ( Fig. 8 ). Rectal sclerites ( Figs. 9, 10 ): dorsally 3 sclerites (two lateral, 1 central), ventrally 2 wing-shaped sclerites.

Variability. The width of frons / diameter of the eye ratio varies between 2.40–2.70 in males and 2.65–2.85 in females. The width/length ratio of pronotum varies between 1.60–1.72 in males and 1.70–1.78 in females. The length/width ratio of elytra varies between 1.47–1.58 in males and 1.60–1.67 in females. The black fascia on elytra is somewhat variable in breadth, usually touching the lateral sides and suture, only in one male the lateral sides and suture are orange. One female has a small black spot surrounding inner margin of eyes posteriorly of canthus and three very small black spots on pronotum (two lateraly near hind angles, one in the middle nearly touching basal margin).

Differential diagnosis. Tituboea purchati sp. nov. belongs to the group of larger species (above 7. mm) with not prolonged protarsi, glabrous elytra and not elevated hind pronotal angles, and is similar to T. arabica (Olivier, 1808) . Both species can be distinguished by the structure of aedeagus which is slender, flat and with distinctly prolonged apex in T. purcharti sp. nov., while robust and with shortly triangular apex in T. arabica ( Figs. 2, 3 ). In the males of T. arabica , the protarsomeres are shortly elongated, not subtriangular as in T. purcharti sp. nov. Protarsomere III in T. arabica is incised ca. to its midlenght, while it is incised to the basal quarter in T. purcharti sp. nov. ( Figs. 6, 7 ). All the specimens of T. arabica known to me also have a different coloration – they always have humeral and subscutellar black spots which are always missing in T. purcharti sp. nov.

Two Afrotropical Tituboea species with not prolonged protarsi, glabrous elytra and not elevated hind pronotal angles, T. capensis Medvedev, 1993 ( RSA) and T. obliquata (Lacordaire, 1848) ( Senegal, Yemen), can be distinguished by two large black spots on pronotum and by the black spots on humeral calli ( T. obliquata ) or on the anterior third of elytra ( T. capensis ). Pronotum of T. purcharti sp. nov. is uniformly orange (or, very rarely, with three very small black spots), and elytra are orange with black transverse fascia behind the middle. All mentioned species differ also in the structure of aedeagus which is triangularly prolonged in T. capensis (but less than in T. purcharti sp. nov.) while simply triangular in T. obliquata ( Figs. 2, 4, 5 ).

In habitus, T. purcharti sp. nov. resembles also some species of the genus Clytra Laicharting, 1781 . Procoxae are separated by a well visible prosternal projection in Clytra species , while it is not visible between procoxae in T. purcharti sp. nov. Aedeagus of T. purcharti sp. nov. with prolonged apex is also similar to that of Barybaena Lacordaire, 1848 species (see ERBER & MEDVEDEV 2003). However, Barybaena species differ in elytra without epipleural lobe and distinct sexual dimorphism (males with enlarged pronotum and fore legs).

Etymology. The new species is dedicated to my friend Luboš Purchart ( Czech Republic, Brno), specialist in Tenebrionidae , who collected a part of the type series.

Collection circumstances and bionomy. Two specimens (male and female) were seen on Trichocalyx obovatus Balf. f. ( Acanthaceae ) at 1:00 p.m. and subsequently collected, another one female was flying in habitat with shrubs dominated by Trichocalyx obovatus and caught by a sweeping net at ca 11:00 a.m. (L. Purchart, pers. comm. 2010). Feeding on Trichocalyx obovatus was not observed; however, there is a possibility that it is the true host plant of T. purcharti sp. nov.

Distribution. Socotra Island ( Yemen).

Figures

Fig. 1. Habitus of Tituboea purchati sp. nov. (holotype, male, 9.6 mm).

Figs. 2–5. Aedeagus (a – dorsal view; b – lateral view). 2 – Tituboea purchati sp. nov.; 3 – T. arabica; 4 – Tituboea capensis (orig. MEDVEDEV 1987); 5 – T. obliquata (specimen from Yemen). Scale bar = 1 mm for Figs. 2, 3 and 5.

Figs. 6–10. 6–7 – Male protarsus. 6 – T. purchati sp. nov.; 7 – T. arabica. 8 – Spermatheca of T. purchati sp. nov. 9–10 – Rectal sclerites of T. purchati sp. nov. 9 – ventral sclerites; 10 – dorsal sclerites. Scale bar = 2 mm for Figs. 6–7, 0.5 mm for Fig. 8 and 1 mm for Figs. 9–10.