Euscelus bivittatus, Hamilton, R. W., 2001

Hamilton, R. W., 2001, New Species Of Euscelus Schoenherr From Central America (Coleoptera: Attelabidae), The Coleopterists Bulletin 55 (4), pp. 453-470 : 466-467

Euscelus bivittatus , new species

Figs. 5 , 12 , 16

Type Locality. Mexico, Chiapas .

Type Series. The type series consists of 19 specimens. The holotype male and allotype female are labeled as follows: Mexico, Chiapas, Finca Agua Clara , viii­25­1981, Coccoloba, G. Vogt ( USNM) . The male holotype has the right antenna missing and the endophallus protruded. The sex and label data of the 17 paratypes are as follows: MEXICO : 1 female, same as primary types; 2 males and 3 females, Tabasco, Jalapa , viii­14­1982, Escobo, G. Vogt ( USNM) ; 1 female, Veracruz, Lake Catemaco , iv.30­v.1, 1969, HF Howden ( CMNC) ; 1 male and 1 female, Ver. [Veracruz], Balzapote (nr. Montepio), 20', 20 May, 1983, CW and L O’Brien and GB Marshall ( CWOB) ; 1 male, Oax. [Oaxaca], Istmo de Tehuantepec , SARH, Coleccion Sanidad Vegetal ( CWOB) ; 1 female, Veracruz, Mex., La Playa Escondida , Las Tuxtlas , 23 March 1980, S. Kaiser, LG Bezark Collection ( CWOB) . COSTA RICA: 1 male, Guan. Prov., Guanacasta, Est. Cacao , 1,000 –1,400 m, Lado SO Vol. Cacao P. N., 21 a May 1992, L­N 323300, 375700, R Vargas ( INBio) ; 1 female, Guanac. Pr., Estac. Cacao, 1,000 –1,400 m SW side Volcan Cacao , Apr. 1988, 323300­375700, M. Espinoza ( INBio) ; 1 female, 28­iv­36, an Gebusch , Hamburg Farm, Reventazon ebene Limon, F. Nevermann ( USNM) ; 1 male, Waldeck , July 22, 1936, CR 4857, Sofia and CH Ballou ( USNM) . PANAMA: 1 female, Canal area, Barro Colorado Natl. Mon. , Gigante Peninsula, 4 Jun ‘92, Fog #8, coll. John E. Tobin ( HPSC) ; 1 male, C. Z. [Canal Zone], Fort Sherman , 1 June ‘78, A Thurman ( HPSC) . Not included in type series: 1 male, [Panama?], G. Vogt ( USNM) .

Type Deposition.. The holotype and allotype are located in the USNM. All paratypes are located in their parent collections except the following: 1 male and 1 female, Mexico, Tabasco, Jalapa , 14­viii­1982, Escobo, G Vogt ( RWHC); 1 male and 1 female, same as previous ( CASC) .

Color and Pubescence. Body reddish­brown throughout. Head, rostrum, antennae, front legs (except coxae) and pronotal stripes darker. Pubescence absent above except for a few small widely spaced erect pale setae on the elytra. Rostral apex, antennae, pygidium, legs and mid­ventrals more of less sparsely set with fine pale reclinate setae.

Size Range. Male 3.6 × 1.6 mm to 5.3 × 2.2 mm; Female 4.1 × 1.8 mm to 5.5 × 2.3 mm.

Adult Descriptive Synopsis. Head weakly conical, widest at base, smooth, shiny; genae with small scattered punctures; with postocular row of small punctures along margin of eye; frons smooth, shiny, without sculpture; eyes moderately protuberant. Rostrum 1/2 length of head; in lateral view weakly arcuate; in dorsal view widened from antennal insertions to apex; width at apex ½ wider than width at base; width at base about twice as wide as frons; dorsal apex sparsely punctured, interspaces smooth, shiny; densely punctured laterally. Antenna inserted dorso­laterally at basal 1/3 of rostrum; club compact; basal and terminal segments subequal in length; middle segment slightly short­ er; terminal segment acuminate. Pronotum wider than long, widest at base, narrowing slightly from base to apex; in dorsal view sides weakly arched out; dorsal anterior edge straight; smooth, shiny, without punctures; with two small depressions, one each side near middle; with two posteriorly divergent longitudinal stripes; anterior collar weakly delimited, ringlike, subequal in width throughout; subbasal constriction linelike, complete throughout; width of basal piece at midline greater than midline width of anterior collar. Elytra 1/4 longer than wide, weakly depressed behind scutellum; in dorsal view sides more or less parallel; striae distinct at base, large, becoming abruptly smaller from behind depression to apex; intervals smooth, shiny, flat, wider than striae, more or less indistinct apically. Thorax with pleura smooth, shiny, with scattered punctures; metathoracic sternum smooth, shiny, weakly bulbous each side of middle. Legs with front pair greatly enlarged; profemora swollen, stalked armed. Abdomen with sterna 1–5 more or less subequal, laterally smooth, shiny; sutures weak between sterna 1–4; suture between 4 and 5 distinct; pygidium moderately punctured.

Profemoral Sexual Dimorphism. The profemur in males ( Fig. 5a ) is bidentate. The disti­ventral denticle is small and acute and the medio­ventral denticle is somewhat larger, bluntly tipped and angled. In some small males the medio­ventral projection is represented only by a small blunt denticle. The profemur in females is armed with a small disti­ventral acute denticle.

Distribution (Fig. 16). This species ranges from southern Mexico to the Republic of Panama.

Comments. Euscelus bivittatus is distinguished by the two stripes on the pronotum ( Fig. 5b ) and the reddish­brown smooth and shiny body. Euscelus bivittatus is similar in size and body coloration to E. corallinus (Gyllenhal) and E. lissus Voss. However , the two pronotal stripes will easily distinguish it from these two species. Also, the males of both E. corallinus and E. lissus have distinct setal tuft patterns on the abdominal sterna that are not present in males of E. bivittatus . The aedeagal median lobe of this species ( Fig. 12b ) has a unique TA and wide bandlike TA guides marked by a basal triangular plate. This is most likely G. Vogt’s species #2 that he associated with Coccoloba sp. in the Polygonaceae family ( Vogt 1992). Vogt did not associate E. corallinus , E. lissus or this species with a pterocoline thief weevil. The specific name refers to the two stripes on the pronotum.

Figures

Figs. 1–6. New species of Euscelus, males,16X; left profemur (a) and dorsal habitus (b). 1) E. oaxacensis; 2) E. stockwelli; 3) E. similis; 4) E. spinosus; 5) E. bivittatus; 6) E. maculicollis.

Figs. 12–14. Species of Euscelus, male genitalia, dorsal view except 14c ventral, 64X; tegmen (a) and median lobe (b and c) with endophallic sac in repose. 12) E. bivittatus, n. sp.; 13) E. maculicollis, n. sp.; 14) E. spinosus, n. sp.