Trichillum (Trichillum) pseudoarrowi, Vaz-De-Mello & Génier, 2005

Vaz-De-Mello, Fernando Z. & Génier, François, 2005, Lectotype designations, new synonymies, and new species in the genera Trichillum Harold and Pedaridium Harold (Coleoptera: Scarabaeidae: Scarabaeinae), Zootaxa 1038, pp. 41-52 : 49-50

Trichillum (Trichillum) pseudoarrowi sp. nov.

( Figs. 9–10 )

Holotype ɗ: PARAGUAY: Boquerón: Gran Chaco, km 145 de Pto. Casado, 25­XI­1950, A. Martínez ( CMNC).

Paratypes: BOLIVIA: Tarija?: Boyoiú, IV­1949, Daguerre (1 CMNC); PARAGUAY: Boquerón: Gran Chaco, km 145 de Pto. Casado, XI­1950, A Martínez (1 BDGC); 25­XI­ 1950 (7 CMNC, 2 FVMC, 1 GHC); Concepción: Horqueta, IV­1934, Schultze (2 CMNC).

Etymology: In reference to the misidentification of this species as T. arrowi Saylor, 1935 in both literature and collections.

Diagnosis: 3.1–3.7 mm. Distinguished by the typical acute clypeal teeth and characteristic head punctation, which is anastomosed instead of well separated and quite ocellate in T. arrowi . Also, eyes are smaller and narrowed posteriorly (in T. arrowi larger and not narrowed posteriorly).

Description: Holotype male. Head: Clypeus with wide and deep U­shaped emargination, with a large and narrow tooth at each side, each tooth parallel­sided, with truncated apex ( Fig. 9 ). Emargination internally and clypeal sides slightly upturned; clypeal sides straight, with a small emargination on the clypeo­genal border. Head covered by large, rugose, setose, transversal punctures, coalescent in the apex and middle of clypeus and distinctly separated on other parts of head, smaller in size on genae. Frons, posterior part of clypeus and genae, with simple small punctures mixed up with the rugose ones. Interocular dorsal space eight times the width of one eye. Pronotum: Pronotal disk with scattered small simple conspicuous punctures. Sides with large, rugose, setose, elongated punctures. Anterior transverse row of setose punctures parallel to anterior border laterally, abruptly posteriorly directed at each side from near to each eye, evanescent in the middle. Basal border with elongated row of setose punctures only on the lateral fourths. Elytra: Elytral discal striae without punctures; interstriae with irregularly spaced small punctures. First, third, and fifth interstriae with apical longitudinal rows of setose punctures, each with up to three setae and restricted to the apical third. Sterna: Metasternal disk with umbilicate punctures, separated by one to three diameters. Metasternal sides with larger umbilicate punctures. Abdomen: Abdominal sternites covered by large umbilicate punctures. Parameres as in figure 10. Legs: Hind femora 1½ times longer than wide in the middle, middle femora normal. Middle and hind tibiae strongly expanded at apex, apical width about 2½ times shorter than tibia. Hind tibia with a small median tubercle on the external ventral face. First tarsomere of the middle legs as long as the second. First tarsomere of the hind legs about 1.2 times longer than the second.

Variation: Paratypes vary in sexual features and size, apart of features related to abrasion of clypeal and fore tibial teeth. Females differ from males by protibial apical internal tooth absent, metasternal disc flat, not concave, and pygidium slightly more transverse.

Remarks: This species is adequately and carefully described under the name T. arrowi by Pereira & Martínez (1959).

Figures

FIGURES 9 – 12. Head (7, 9, and 11) and parameres (8, 10, and 12), dorsal view. 7 – 8. Trichillum tishechkini n. sp. 9 – 10. Trichillum pseudoarrowi n. sp. 11 – 12. Trichillum cordobense n. sp.