Barrotillus kropotkini Rifkind, 1996

Burke, Alan & Zolnerowich, Gregory, 2017, A taxonomic revision of the subfamily Tillinae Leach sensu lato (Coleoptera, Cleridae) in the New World, ZooKeys 179, pp. 75-157 : 91-92

Barrotillus kropotkini Rifkind, 1996 Figs 1E, 7D, 8B

Paratype.

One male paratype examined.

Type locality.

Francisco Morazán, Tegucigalpa, Honduras. Type depository: Natural History Museum of Los Angeles (LACM).

Distribution.

Francisco Morazán, Honduras.

Differential diagnosis.

This monotypic species is most closely allied to members of Neocallotillus , with a particular resemblance to Neocallotillus elegans . A number of characters are useful to separate these species: Barrotillus kropotkini has the antennae composed of 11 antennomeres with the segments moderately serrate (Fig. 1E; 8B), the anterior portion of the pronotum is strongly constricted posteriorly, and the pronotal disc is coarsely and deeply punctate (Fig. 7D). Neocallotillus elegans has the antennae with 10 antennomere which are pectinate in males (Fig. 8 D–E) and serrate in females (Fig. 8-F), the pronotal disc is somewhat constricted posteriorly (Fig. 2B), and the punctations on the elytral disc are shallowly and slightly impressed.

Redescription.

Male. Form: Body elongate, slender, small size, 5.3 mm. Color: Head, dorsal portion of pronotum, elytra, abdomen, legs and labial palpi piceous; ventral and posterior portion of pronotum, prosternum, mesoventrite, labrum, mouthparts and posterolateral portion of metaventrite rufous, antennae dark-brown; each elytron with one macula and one fascia, both markings white and raised from elytral surface, the macula is located on the median region of the anterior third of the elytral disc and the fascia is located on the median region of the elytral disc, the fascia begins on the epipleural fold and do not reach the elytral suture (Fig. 1E).

Head: Including eyes wider than pronotum; integument smooth, punctate; eyes large, finely faceted, anteriorly emarginate; frons not bi-impressed; clothed with semi-erect setae of two sizes; antennae reaching humeral angles, consisting of 11 antennomeres; antennomeres 2-4 small, slightly robust, filiform; antennomeres 5-6 feebly serrate; antennomeres 7-10 moderately serrate; antennomeres 5-10 gradually increasing in size; eleventh antennomere as long as the combined length of antennomeres 8-10; last antennomere rather compressed at middle (Fig. 8B); terminal labial palpi securiform; terminal maxillary palpi cylindrical.

Thorax: Pronotum longer than broad, campanulate; disc convex; sides sinuate; clothed with long, semi-erect setae intermixed with less numerous, long, semi-erect setae; widest on anterior margin; conspicuously constricted posteriorly; moderately punctate, punctations rather deep and coarse. Prosternum smooth, punctate, finely vested with pale, semirecumbent setae. Mesoventrite smooth, feebly punctate, coarsely deeply punctate, finely vested with some pale, semi-recumbent setae. Metaventrite slightly punctate, surface smooth, vested with fine, recumbent and semi-recumbent setae, longitudinal depression and metaventral process absent. Metepisternum visible throughout its length in lateral view.

Elytra: Humeri indicated, slender, elongate, subparallel, slightly broader on posterior third, convex on anterior third, then moderately compressed in middle third, and conspicuously convex again in posterior third, sinuosity observable on lateral view, sculpturing consisting on shallow punctations irregularly arranged, punctations extending to apex, elytral apices rounded, feebly dehiscent, interstices at elytral base about 2.5 × the width of punctation; scutellum subquadrate, profusely vested with fine, recumbent and long setae, not compressed; epipleural fold compete, narrowing toward apex.

Legs: Femora shiny; smooth; vested with semi-recumbent setae interspersed with some semi-erect setae. Tibiae more profusely vested than femora; vestiture consisting on fine, short, recumbent setae on proximal face of tibiae and semi-erect setae on distal face of tibia. Pulvillar formula 4-3-3. Two tarsal denticles, tarsal denticles trigonal in shape.

Abdomen: Six visible ventrites. Ventrites 1-5 shiny, smooth, subquadrate, vested with fine, short, vested with semi-recumbent and recumbent setae; not compressed laterally. Fifth visible ventrite subtriangular; slightly clothed with recumbent setae; lateral margins oblique; posterior margin truncate. Sixth visible ventrite small, shiny, smooth, conspicuously broader than long; lateral margins strongly oblique; posterior margin broadly, shallowly emarginate; posterolateral angles rounded. Sixth tergite feebly concave; surface smooth; lateral margins strongly oblique; posterior margin notched medially; posterolateral angles semicircular in shape; lateral and posterior margins clothed with conspicuously long, erect setae. Sixth tergite extending beyond apical margin of sixth visible ventrite; fully covering sixth ventrite from dorsal view.

Aedeagus: Not available.

Sexual dimorphism: Rifkind (1996) indicated the presence of antennal differences between the male and the female of this species. The eleventh antennomere of the female is somewhat shorter than that of the male; also, in the female, this segment is not medially compressed. Additional differences between males and females are seen in the sixth sternite, where females have the posterior margin of this segment complete and rounded, rather than notched, as observed in males.

Material examined.

PARATYPE: 1 male: Honduras: Francisco Morazán, El Rincón, Tegucigalpa, X-5-1988, R. D. Cave.

Remarks.

Rifkind (1996) mentioned the close resemblance this genus has with many species of Stenocylidrus Spinola, checkered beetles restricted to the Afrotropical region and some Australasian islands. Rifkind further indicated that the campanulate state of B. kropotkini is similar to certain species of Cladiscus Chevrolat, Pseudopallenis Kuwert and Eburneocladiscus Pic, those genera occurring in the tropical regions of Africa and Madagascar. In the New World, Barrotillus kropotkini is most closely allied to Neocallotillus . The campanulate state of the pronotum of this species can be considered a homoplasy shared with many tillinids, rather than an indication of relatedness.