Xenopygus bicolor (Laporte)

Caron, Edilson, De Castro, Jessica C., Da Silva, Maycon R. & Ribeiro-Costa, Cibele S., 2016, Phylogeny and revision of a colorful Neotropical genus of rove beetles: Xenopygus Bernhauer (Coleoptera: Staphylinidae), Zootaxa 4138 (1), pp. 59-82 : 73

Xenopygus bicolor (Laporte)

( Figs 3 , 6, 31, 34, 40, 43, 46, 58)

Staphylinus bicolor Laporte, 1835: 115 (original description, type locality: ‘Cayenne’). Laporte, 1840: 177 (characteristics, distribution). Note: preoccupied name, primary homonym of Staphylinus bicolor Paykull, 1789 (currently Lesteva analis ), but was held according to plenary power of ICZN Committee in Opinion 2053 (ICZN 2003). Discussion about this topic see ( Herman 2001a, Herman 2002 and ICZN 2003). Note: Irmler (1982) designates the Neotype from a specimen from Erichson’s collection, also from ‘Cayenne’.

Philonthus bicolor Erichson, 1840: 495 (transferred to Philonthus , characteristics, distribution).

Xanthopygus bicolor Kraatz, 1857: 540 (transferred to Xanthopygus ); Solsky, 1872: 306 (cited as Xanthopygius); Sharp, 1876: 132 (male characteristics, distribution).

Lampropygus bicolor Sharp, 1884: 347 (Error: Sharp referred to Erichson’s species).

Xenopygus bicolor Bernhauer, 1906: 196 (transferred the species to Xenopygus ); Bernhauer & Schubert, 1914: 405 (catalog); Irmler, 1979: 31 (characteristics); Irmler, 1982: 209 (Neotype designation: characteristics); Herman, 2001a: 54 (nomenclatural discussion); Herman 2001b: 3610 (catalog); Rodriguez et al., 2012: 233 (characteristics, biological notes).

Type material. Neotype, female, deposited in ZMHB, not studied.

Diagnosis. Xenopygus bicolor is easily distinguished from X. analis and X. confusus by the color of the head and pronotum, metallic blue to green, and elytra yellow to dark brown; apical half of abdominal segment VI and basal half of segment VII evidently darker than the remainder of abdomen ( Fig. 3 ) and sternite VIII of male with apical margin slightly emarginate at middle (Fig. 34).

Redescription. BL: 9–17 mm, BW: 3.4 mm. Head and pronotum metallic blue to green, elytra and abdominal segments yellowish, apical half of abdominal segment VI and basal half of segment VII evidently darker than the remainder of abdomen ( Fig. 3 ). Pronotum with setal punctuations forming a pair of longitudinal lines in the median region of disc and distributed in each lateral third, more evident in the anterior half (Fig. 6).

Eyes slightly longer than half of the head. Antenna scape equal to slightly longer than antennomeres II and III combined; antennomere IV as long as wide; antennomeres V–XI with microsetae; antennomere XI apparently symmetric. Mesoventrite process with apex truncate and wide; and metatarsomeres II–IV slightly bilobate. Tergite III–V with arched carina; sternite VII of male with wide porous structure at middle (Fig. 31); sternite VIII of male slightly medially emarginate (Fig. 34). Median lobe with bulbous base ( Fig. 40 ); apex rounded to pointed, subapically with a small tooth in hook shape in ventral surface (Fig. 43); parameres fused in a single plate and exceed the apex of median lobe, apex round, apical two thirds with peg setae forming two irregular lines near the lateral margins (Fig. 46).

Geographical record. Guyana: Demerara. Equador: Orellana. Peru: Loreto; Madre de Diós. Bolivia: La Paz Department. Brazil: Amazonas; Pará; Acre; Rondônia; Mato Grosso ( Fig. 58 ).

Biological notes. Xenopygus bicolor was found on tree barks and fungi, collected with feaces baited pitfall traps, and with flight interception traps.

Figures

FIGURES 2 – 4. Habitus. 2, Xenopyugs analis; 3, X. bicolor; 4, X. confusus. 5 – 7. Detail of head and pronotum. 5, X. analis; 6, X. bicolor; 7, X. confusus. Scale = 2 mm.

FIGURES 39 – 41. Aedeagus, lateral view. 39, X. analis; 40, X. bicolor; 41, X. confusus. 42 – 44. Apex of median lobe, ventral view. 42, X. analis; 43, X. bicolor; 44, X. confusus. 45 – 47. Apex of paramere, dorsal view. 45, X. analis; 46, X. bicolor; 47, X. confusus. Scale = 0.5 mm.

FIGURES 57 – 59. Geographical distribution of Xenopygus species. 57, X. analis; 58, X. bicolor (dots) + X. confusus (triangles); 59, X. cordovensis (dots) + X. sancticamillus, sp. nov. (triangles) + X. petilicolis, sp. nov. (squares).