Parahyliota balli Thomas, 2009

Thomas, Michael C., 2009, First record of the genus Parahyliota in the New World (Coleoptera: Silvanidae: Brontinae), Insecta Mundi 2009 (70), pp. 1-4 : 1-4

Parahyliota balli Thomas , new species

Fig. 1-8

Diagnosis. This species is the only member of the tribe Brontini known to occur in the Neotropics. The genus is included in a key to world brontine genera in Thomas (2004).

Description. Holotype, male ( Fig. 1-3 ), deposited in USNM, with following label data: “ MEX. Oaxaca 13.4 km. s. Totontepec cloud forest 2530m. in litter 79-37 June 16, 1979 /MEXICAN EXP. 1979 J. S. Ashe, G. E. Ball & D. Shpeley collectors”.

Body. With the characters of Parahyliota Thomas as described by Thomas (2004), plus: Length, 6.2 mm; elongate, parallel-sided, dorso-ventrally compressed; dark testaceous in color ( Fig. 1 ).

Head. Transverse, 1.4x wider than long; excavate over antennal insertions, with a shallow transverse impression anterior to antennal insertions and a deep transverse impression posterior to eyes. Mandibles broad, angulate, each with a vertically-directed, long curved tooth arising from the dorsal surface. Antennae elongate, filiform, longer than body; scape slightly sinuate, very elongate, as long as next three antennomeres, attaining base of pronotum; pedicel short. (Holotype missing most antennal flagellomeres. Proportions of antennomere lengths of male paratype are: 5.25:1.00:2.00: 2.25:2.25:2.50:2.50:2.50:2.25:2.00:2.00; surpassing length of body by about three antennomeres.) Dorsal surface densely punctate, punctures about equal in size to an eye facet, separated by less than one puncture diameter, each puncture subtending a long pale seta; impunctate above antennal insertions; surface between punctures microreticulate laterally, smooth and shining medially; a tear shaped fovea bordered anteriorly with a blunt tubercle is present on each side of frons within antennal insertion. Eyes large, not convex, temple narrow posteriorly, about 2 eye facets in width ( Fig. 3 ).

Pronotum. Transverse, 1.3x wider than longer, widest across apical angles; rectangular in shape, lateral margins slightly converging posteriorly; disk depressed; margins denticulate, anterior angle right, with a distinct tooth beyond anterior angle, posterior angle obtuse ( Fig. 2 ); surface sculpture and pubescence as on head.

Elytra. Elongate, 2x longer than combined width, parallel-sided, converging conjointly from about apical third to suture; laterally narrowly costate, the lateral margin narrowly explanate; disc with six rows of punctate striae, striae not impressed; a single row of smaller punctures between each stria; each puncture subtending a long suberect pale seta.

Genitalia. Aedeagus as is Fig. 6 ; parameres highly reduced ( Fig. 7 ), abdominal segments VIII and IX forming claspers as in Fig. 8 .

Female. Allotype ( Fig. 4-5 ) with same data as holotype, deposited in USNM. Similar to male, differing as follows: Length, 6.4 mm. Head, 1.8x wider than long; pronotum, 1.3x wider than long; elytra, 2.1x longer than combined width; color castaneous; punctation and pubescence as in male; mandibles without dorsal tooth and frons without blunt tubercles ( Fig. 5 ); antennae about as long as body, scape attaining middle of pronotum; ratios of antennomere lengths: 5.0:1.0:2.0:2.3:2.3:2.3:2.0:2.0:1.6:2.0.

Paratypes. Seven with label data as follows: 2, same data as holotype ; 5, “ MEX. Oaxaca 16.6 km. s. Totontepec cloud forest 2540 m in litter 79-35 June 16, 1979 /MEXICAN EXP. 1979 J. S. Ashe, G. E. Ball & D. Shpeley collectors”. Deposited in CNCI, FSCA, UNAM, and UASM .

Variation. Paratypes range in color from testaceous to castaneus; the testaceous specimens appear teneral. Male paratype is very similar to holotype, length 5.8 mm. Female paratypes range in length from 5.7 mm to 5.8 mm.

Etymology. I take great pleasure in naming this species in honor of George Ball, pre-eminent carabidologist and friend, who was one of the collectors of the type series.

Discussion. George Ball (in litt.) wrote that his field notes indicate that the specimens were actually collected under bark and that the “in litter” referred to carabids collected at the same localities. At both localities specimens of a species of the silvanid genus Aplatamus Sharp were collected. Individuals of that genus seem to be infrequently collected.

The male of P. balli possesses mandibular horns, which otherwise occur only in the African and Madagascan members of Parahyliota . None of the Asian species is known to possess mandibular horns.

Figures

Figure 1-3. Parahyliota balli Thomas, new species, male holotype. 1) Dorsal habitus. 2) Head and pronotum. 3) Front of head and mandibles.

Figure 4-5. Parahyliota balli Thomas, new species, female allotype. 4) Dorsal habitus. 5) Head and pronotum.

Figure 6-8. Parahyliota balli Thomas, new species. Male genitalia. 6) Aedeagus. 7) Tegmen. 8) Claspers, composed of abdominal segments VIII and IX.