Diceroderes Solier, 1841

Smith, Aaron D. & Cifuentes-Ruiz, Paulina, 2015, Revision of Diceroderes Solier (Coleoptera: Tenebrionidae: Toxicini: Eudysantina), with Descriptions of Four New Species, The Coleopterists Bulletin (mo 14) 69, pp. 55-72 : 57-58

Diceroderes Solier, 1841

Diceroderes Solier 1841: 46 . Lacordaire 1859: 356; Redtenbacher 1868: 127; Pascoe 1871: 349; Champion 1885: 96; Waterhouse 1887: 448; Blackwelder 1945: 533; Gebien 1911: 432, 1940: 1090 (623); Doyen 1989: 294.

Prosomenes Dejean 1836: 216 , nomen nudum

Type Species. Diceroderes mexicanus Solier, 1841 , by monotypy.

Diagnosis. Diceroderes is easily distinguished from all other Eudysantina genera by a unique combination of the following characters: Pronotum with two anteriorly projecting horns; antenna with three-segmented club, antennomeres forming club fused, but with sutures visible; clypeus depressed and projecting past genal margin; apterous; abdominal ventrite 5 lacking submarginal groove, membranes between ventrites concealed. The genus Mechanetes Waterhouse, 1887 (Southeast Asia), currently in Stenochiinae pending a review of the worldwide Eudysantina, is similar to Diceroderes , but can be separated based on the presence of visible abdominal membranes. The presence of two pronotal horns separates Diceroderes from all other genera currently in Eudysantina with the exception of Eudysantes (Southeast Asia and Africa), which

2) Hind tibia. have fully developed wings and variable formations of the antennal club.

Redescription. Length 7.2–9.5 mm, width 3.8–4.9 mm (n = 74 specimens). Body generally coated with thin, shellac-like pruinescence, often capturing debris on surface. Color ferruginous to black. Head: Frontoclypeal and genoclypeal sutures distinct, shallow to deeply impressed; clypeus depressed below gena and frons, extending beyond genal margin, anterior margin straight or slightly rounded, with thin, weakly raised lip. Eye elongate oval to slightly reniform; raised U-shaped lobe present behind eye, sharply constricted posteriorly. Labrum smooth, without transverse medial ridge; mandible bifid at apex, without dorsal protrusions or cusps; maxillary palp 4-segmented, apical segment securiform; mentum trapezoidal, widest at anterior margin. Antenna 11-segmented, distinct 3-segmented club present, club antenommeres fused but with sutures clearly visible. Prothorax: Pronotum with 2 stout, anteriorly directed horns arising sublaterally from apical half of pronotum. Pterothorax: Apterous, elytral cavity sealed. Elytral basal margin crenulate. Scutellum exposed, partially projecting beyond elytral basal margin. Mesocoxal cavities open. Legs: Mesotrochantin exposed; femora without spines or other protrusions; tibia without raised callosities, inner apical margin with 2 distinct socketed spurs, apical spine between spurs present or absent; tarsal formula 5-5-4. Abdomen: Membranes between visible ventrites concealed; sutures between ventrites sulcate ( Fig. 39 ), sulci deeper between ventrites 3–5; ventrites 1–3 in males medially clear of pruinescence and with larger punctures than surrounding area, representing channels to dense presumably glandular tissue attached to inner surface of ventrites ( Fig. 38 ); ventrite 5 lacking submarginal groove; abdominal defensive reservoirs present.

Etymology. The generic name is Greek and likely refers to the two horns on the pronotum. It is masculine.

Distribution. Mexico: Chiapas, Hidalgo, Oaxaca, Puebla, Veracruz; Guatemala: El Progreso, Izabal, Baja Verapaz; Honduras: Cortes.

Figures

Figs. 38–39. Diceroderes subtriplehorni, allotype