Euscelus similis, 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 : 460-461

publication ID

https://doi.org/ 10.1649/0010-065X(2001)055[0453:NSOESF]2.0.CO;2

persistent identifier

https://treatment.plazi.org/id/2543E976-FFE2-423D-F0E5-A6CF66B1FBBA

treatment provided by

Tatiana

scientific name

Euscelus similis
status

sp. nov.

Euscelus similis , new species

Figs. 3 View Figs , 11 View Figs , 15 View Fig

Type Locality. Belize, Belmopan

Type Series. The type series consists of 12 specimens. The holotype male and allotype female are labeled as follows: Belize, 39 mi n. e. of Belmopan , 17­viii­1981, Terminalia, G. Vogt ( USNM) . The sex and label data of the 10 paratypes are as follows: 3 males and 2 females, label data same as primary types; 2 males and 2 females, Belize, Corozal, viii­1980, Terminalia, G. Vogt ( USNM) ; 1 female, Guatemala, Livingston, v­5 [no year], Barber & Schwarz coll. ( USNM) .

Type Deposition. All types are located in the USNM except the following: 1 male and 1 female, same data as primary types ( RWHC) .

Color and Pubescence. Body reddish­brown; sides of head, pronotum, metasternum, femora and all pleura darker; middle and hind legs paler. Elytra with slightly raised yellowish markings. Pubescence absent above on head, pronotum and elytra; elytra with only a few small widely spaced erect pale setae mainly near apical and apico­lateral margins. Rostral apex, antennae, pygidium, legs and mid­ventrals more or less sparsely set with fine pale reclinate setae.

Size Range. Male 4.0 × 1.7 mm to 4.7 × 2.0 mm; Female 3.9 × 1.6 mm to 4.7 × 2.0 mm.

Adult Descriptive Synopsis. Head more or less rectangular, weakly constricted across middle; vertex moderately punctured, interspaces smooth, shiny; with narrow postocular punctate band along margin of eye; genae more or less densely punctured; frons with weak median sulcus; eyes moderately protuberant. Rostrum short, about ½ length of head; in lateral view weakly arcuate; in dorsal view distinctly widened from antennal insertions to apex; width at apex 1 ½ times as wide as base; base about 2 ½ times wider than frons; dorsal apex moderately punctured. Antennae inserted dorso­laterally just behind basal 1/3 of rostrum; club compact; basal and middle segment subequal in length; middle segment slightly shorter; terminal segment acuminate. Pronotum wider than long; in dorsal view sides arched out in anterior half; dorsal anterior edge weakly emarginate through middle; anterior and posterior width subequal; with widely spaced fine punctures; moderately punctured postero­laterally; interspaces smooth, shiny; with two deep oblique grooves near middle; grooves meet at middle forming wide V­shape and median depression; anterior collar distinct, widest through middle; subbasal constriction linelike, indistinct laterally; width of basal piece at midline slightly less than midline width of anterior collar. Elytra about 1/4 longer than wide; widest behind middle; weakly depressed in middle behind scutellum; weakly raised around scutellum; declivity abrupt; strial punctures distinct throughout; intervals smooth, shiny, weakly convex, about as wide as striae; each elytron with twelve yellowish marks; two at base, larger one adjacent to scutellum on intervals 1 and 2, smaller one at base of interval 4, more or less connected by narrow yellowish interspaces; one postero­lateral to humerus; two in middle near elytral suture on intervals 1 and 2; one dorso­lateral beyond middle; and six barlike interval marks from declivity to apex, covering intervals 1, 2, 3, 5, 6 and 7. Thorax with pleura and lateral edges of sterna coarsely punctured; metasternum smooth, bulbous each side of middle. Legs with front pair greatly enlarged; profemora swollen, stalked, armed. Abdomen with sterna 1–3 subequal, smooth, shiny, minutely crenulate; sutures distinct through middle, weak laterally; with scattered lateral punctures; sterna 4 and 5 subequal, slightly shorter along midline than sterna 1–3; suture between sternum 4 and 5 complete; sternum 5 distinctly punctured; pygidium and tergum between elytral apices densely punctured.

Profemoral Sexual Dimorphism. The profemur in males is armed with a disti­ventral thornlike projection, a medio­ventral acuminate projection that is strongly angled (bent over) and an oval setose pit near the base of the medioventral projection ( Fig. 3a View Figs ). The profemur in females is armed only with an disti­ventral thornlike projection and a small straight medio­ventral denticulate projection.

Distribution ( Fig. 15 View Fig ). Eleven of the 12 specimens in the type series are from Belize (Belmopan and Corozal) and a single female specimen is recorded from Livingston, Guatemala.

Comments. Euscelus similis is easily distinguished from the other Central American euscelines by the profemoral armature and the elytral markings ( Fig. 3 View Figs ). It is very similar to E. breviceps but lacks the toothlike projection on the postero­lateral portion of the elytra and differs in profemoral armature. The medio­ventral profemoral projection in males of E. breviceps is smaller and not angled and the medio­ventral profemoral projection in females of E. breviceps is much smaller and denticulate. The aedeaguses are very different in E. breviceps and E. similis (compare Figs. 10 and 11 View Figs ). The apex of the tegminal cap­piece in E. similis is narrow and fingerlike, the apex of the ventral plate of the median lobe is narrowly pointed, the TA is narrow and elongate and the TA guide is surrounded numerous bluntly tipped denticles. The yellowish elytral marks on the pinned specimens of E. similis , E. breviceps and E. stockwelli take on a greenish luster when the specimens are hydrated. These marks may actually be bright green in living specimens. Buchannan (1935, unpublished note on USNM specimen label) noted that similar elytral marks on Euscelus sexmaculatus (Chevrolat) from Haiti were bright green when the specimen was collected. This species has been associated with Terminalia spp. by G. Vogt but has not been associated with a pterocoline egg predator. It is probably associated with Pterocolus torreyae Hamilton which is known to attack E. breviceps (Vogt 1982) . The species name is in reference to the external similarity of this species to E. breviceps

USNM

Smithsonian Institution, National Museum of Natural History

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Coleoptera

Family

Attelabidae

Genus

Euscelus

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