Oxyepoecus longicephalus, Albuquerque, Nicolas Lavor De & Brandão, Carlos Roberto F., 2004

Albuquerque, Nicolas Lavor De & Brandão, Carlos Roberto F., 2004, A Revision Of The Neotropical Solenopsidini Ant Genus Oxyepoecus Santschi, 1926 (Hymenoptera: Formicidae: Myrmicinae). 1. The Vezenyii Species- Group, Papéis Avulsos de Zoologia 44 (4), pp. 55-80 : 69-71

Oxyepoecus longicephalus sp. nov.

( Figs. 4 a-c)

Oxyepoecus longicephalus Albuquerque and Brandão. Holotype worker, Brasil: Rio Grande do Sul: Itatí 29°30’S, 50°10’W, 28.v.1997, J. Ketterl [col.], CPCN Pró-Mata, deposited in MZSP.

Paratype: workers. Brasil: Rio Grande do Sul: Itatí 29°30’S 50°10’W, 29.v.1997, J. Ketterl [col.], CPCN Pró-Mata deposited in MZSP . São Paulo: Cunha 23°15’S, 45°00’W, 21-22.iv.2001, A.A. Tavares, R . R . Silva cols, P.E. Serra do Mar, Winkler, deposited in MZSP .

Etymology: The shape of the head (f.f.v.) where the length is more developed than the width.

Worker: Holotype and paratype within brackets t.l.= 3.00 (3.06); h.l.= 0.72 (0.72); h.w.= 0.48 (0.50); s.l.= 0.42 (0.46); m.l.e.= 0.08 (0.12); m.w.pr.= 0.42 (0.45); a.l.= 0.84 (0.84); h.f.l.= 0.41 (0.45); m.w.p.= 0.18 (0.22); m.w.pp.= 0. 30 (0. 30); c.i. 66 (69). Color chestnut brown to dark brown. Integument smooth and shining, with the following exceptions: frontal carinae longitudinally costulate, prolonged posteriorly, surpassing the level of the superior orbit of the compound eyes; genae with well marked longitudinal rugae that do not reach superiorly the inferior orbit of compound eyes but reach inferiorly the mandibular insertion; pronotum with some irregular and superficial rugae; the neck, the mesopleuron (anepisternum and katepisternum), the metapleuron and the propodeum almost entirely covered by irregularly reticulate sculpture, except around the propodeal spiracle, which is smooth; the inferior region of the metapleuron with two longitudinal and well marked costulae that prolong over the metapleural gland bulla; superior face of the petiole peduncle and lateral face of the petiole also with the irregularly reticulate sculpture; the superior and lateral face of the postpetiole with some irregular rugae that give a rough aspect. Hairs abundant, short and decumbent, irregularly distributed on cephalic disc; scarce, long, suberect and relatively curved forwards on pronotum; metapleuron and mesopleuron with scarce and short hairs; propodeum, petiolar node, postpetiole, and gaster with some long and erect hairs, somewhat backwards oriented.

Head as shown in Fig. 4a (f.f.v.). Mandibles elongated with a broad and relatively shallow diastema between the basal and subbasal tooth. Anterior teeth of clypeus with small, blunt and lobe-like lateral denticles. Frontal carinae relatively short, subparallel, reaching the level of the inferior orbit of the compound eyes, the maximum width between their outer edges less than a fifth of the head width. Compound eyes small, with about 3-5 facets r.g.d.; total number of ommatidia about 8. Antennal scape failing to reach the occipital corner by a distance larger than the maximum thickness of the scape. Funicular segment I as long as II-IV combined, segments II-VII distinctly broader than long, VIII and IX as long as broad.

Mesosoma as shown in Fig. 4b . Promesonotum immarginate in front and laterally; shoulders marked, but without a defined angle. Metanotal groove perceptible by a break in the profile. Dorsal face of the propodeum posteriorly with two acute teeth. Declivous face laterally marginate and weakly carinate.

Petiole in dorsal view as shown in Figs. 4 b-c, node high and rounded at superior face, antero-posteriorly compressed but not scale-like, about 2/3 as broad as postpetiole; subpetiolar process as a sagital and undulated keel anteriorly ending in a prominent toothshaped plate. The postpetiole broad, in a scale like fashion, the level of the superior face lower than the petiole node; subpostpetiolar process small, almost imperceptible, extremely shallow.

Gyne unknown.

Male unknown.

Diagnosis, distribution and comments

The exclusive character of the workers of O. longicephalus is mainly the proportion between the head length and head width (very elongate, low c.i.); also the irregularly reticulate sculpture over the body (visible only at magnifications over 80 X). O. longicephalus was recorded in only one locality at south Brazil, and one at southern Brasil (fig. 8), geographically separated.

Examined material: Brasil: Rio Grande do Sul [: [Itatí], CPCN Pró-Mata , 28.v.1997, J.Ketterl [col.] 29°30’S 50°10’W, Mata Atlântica, 670-690 m, (Winkler) WnB 27 (1 Ψ holotype) ; Rio Grande do Sul, CPCN Pró-Mata, 15.iv.1997, J.Ketterl [col.] 29°30’S 50°10’W, Araucaria Forest , ~ 900 m, (Winkler) WnA 17 (1 Ψ paratype, without antennae) ; São Paulo: Cunha, P.E. Serra do Mar , 21-22.iv.2001, A.A.Tavares & R. R. Silva cols 23°15’S 45°00’W Winkler 48 (1 Ψ paratype, the gaster is partially destroyed) .

Figures

FIGURE 4. Scanning electron micrograph of the workers of O. longicephalus; a) head in full-face view; b) mesosoma in profile view; c) petiole in dorsal view.