Oxyepoecus reticulatus Kempf, 1974

Albuquerque, Nicolas Lavour de & Brandão, Carlos Roberto Ferreira, 2009, A revision of the Neotropical Solenopsidini ant genus OXYEPOECUS Santschi, 1926 (Hymenoptera: Formicidae: Myrmicinae). 2. Final. Key for species and revision of the Rastratus species-group, Papéis Avulsos de Zoologia 49 (23), pp. 289-309 : 303-304

Oxyepoecus reticulatus Kempf, 1974

( Figs. 4 a-c, 8)

Oxyepoecus reticulatus Kempf, 1974:502 (description of worker and gyne); Bolton, 1995:302 (catalogue).

Worker (Holotype): t.l. = 1.90 (1.90-2.30); h.l. = 0.51 (0.48-0.56); h.w. = 0.41 (0.38-0.44); s.l. = 0.31 (0.29-0.35); m.l.e. = 0.07 (0.05-0.07); m.w.pr. = 0.31 (0.27-0.32); a.l. = 0.57 (0.51-0.62); h.f.l. = 0.33 (0.29-0.37); m.w.p. = 0.15 (0.13-0.15); m.w.pp. = 0.23 (0.16-0.23); c.i. 82 (77-84). Color chestnut brown. Mandible, antennae, ventral face of head, declivous face of propodeum, legs, petiolar node, postpetiole and gaster shining, smooth to very superficially and indistinctly sculptured. Remaining parts opaque with following sculpture: head dorsum and vertex irregularly costulate, except for smooth and shining strip between frontal carinae. Pronotum longitudinally costulate dorsally and laterally; strongly punctute on dorsum, weakly to imperceptible on side, mesonotum and remaining mesosomal side irregularly reticulate and punctate, coarser on metapleuron; basal face of propodeum with anterior half transversely costulate, posterior half with weak and almost imperceptible transverse costulae; declivous face shining. Short hairs relatively abundant on head; curved mesad on head dorsum, anteriorly curved on sides; subdecumbent to decumbent on antennae and legs; suberect and moderately abundant on dorsum of mesosoma, waist and gaster, the latter also with some shorter, recurved hairs.

Head in Fig. 4a (f.f.v.): Mandible with basal border slightly longer than chewing border, with basal tooth separated from subbasal tooth by shallow diastema. Anterior tooth of clypeus with lateral denticle. Frontal carinae short, subparallel, little expanded laterad, ending at level of anterior orbit of eye, maximum width between their outer edges less than one third of head width. Compound eye very small, with some 4 facets r.g.d., total number of ommatidia circa 12. Scape fails to reach vertexal corner by distance exceeding maximum scape width. Funnicular segment I longer than VIII and IX taken individually, as long as II-IV combined; segments VIII and IX about as long as broad. Vertexal margin straight.

Mesosoma (p.v.) in Fig. 4b . Promesonotum gently convex, transition between the dorsal and lateral surfaces of pronotum continuous, almost rounded. Metanotal groove not impressed in lateral view, metanotal suture indistinct. Basal face of propodeum posteriorly with a very small but pointed tooth. Declivous face laterally subcarinate.

Petiole strongly pedunculate (d.v.), node high and dorsally rounded, somewhat compressed antero-posteriorly, but not much expanded laterad; subpetiolar process anteriorly shaped as small tooth, obliquely and forward oriented. Postpetiole much broader than petiole, expanded laterad; subpospetiolar process with anterior margin projecting as crest.

Gyne (Paratype): t.l. = 2.50; h.l. = 0.55; h.w. = 0.45; s.l. = 0.33; m.l.e. = 0.11; m.w.pr. = 0.40; a.l. = 0.71; h.f.l. = 0.37; m.w.p. = 0.17; m.w.pp. = 0.27; c.i. 83. Resembling worker, with distinctive characters of caste. Cephalic dorsum finely, longitudinally costulate, with conspicuous interstitial punctures, sculpture attaining both vertex and eyes, as in worker. Eye with some 10 facets r.g.d. Laterotergite of pronotum, katepisternum and rest of mesosomal sides with horizontal costulae, the interstitial microsculpture almost imperceptible. Pronotum dorsolaterally finely and obliquely costulate. Scutum and scutellum longitudinally costulate, opaque. Basal face of propodeum with about 10 transverse rugulae. Propodeal teeth short but pointed, distance between their tips subequal to width of petiole. Posterior surface of postpetiole with several transverse costae. The available gyne specimen had no wings.

Male: unknown.

Examined material: BRAZIL: Minas Gerais: Viçosa , 06.v.1988, M.V.B. Queiroz col., cafezal [coffee plantantion] [20°45’S, 42°52’W] (1 S) ; Paraná: Guaragi , v.1964, F. Plaumann leg. # 4008, [25°16’S, 50°14’W] (1 S paratype) ; same locality, v.1964, F. Plaumann leg. # 4580, collected 1000 m 25°16’S, 50°14’W (1 S paratype) ; Mariópolis, without date, F. Plaumann leg. [26°21’S, 52°33’W] (1 T paratype); Tunas, Parque das Lauráceas, 21-29.ii.2001, [R.R.] Silva and [F.] Eberhardt cols., transecto 1 Winkler 43 [24°51’16”S, 48°43’00,4”W] (3 S); Rio Azul , x.1959, F. Plaumann [col.] # 3188, 1000 m [25°44’S, 50°47’W] (1 S paratype) ; Rolândia , 06.iv.1955, W. Kempf [col.] # 1414 [23°18’S, 51°22’W] (2 S paratypes) ; Santa Catarina: Chapecó , v.1957, F. Plaumann leg. [27°06’S, 52°37’W] (5 S paratypes) ; same locality, vi.1960, same collector, (4 S paratypes) ; same locality, vii.1960, same collector, (3 S paratypes) ; Concórdia , vii.1958, F. Plaumann leg. [27°13’S, 52°01’W] (1 S paratype) ; Linha Facão , v.1957, F. Plaumann [col.] (6 S paratypes) ; P. Bormann, xii.1957, F. Plaumann [col.], (1 S paratype); Seara ( Nova Teutônia ), viii.1952, F. Plaumann [col.], Borg [meier] collection # 5954 [27°09’S, 52°18’W] (12 S holotype and paratypes) ; same locality, viii.1952, F. Plaumann [col.] 27°11’S, 52°23’W (6 S paratypes) ; Seara, v-xii.1998, Rogério R. Silva col. 27°09’S, 52°18’W, transecto 1 Winkler (2 S) ; São Paulo: Agudos , 25.iii.1955, W. Kempf [col.], # 1405 [22°27’S, 49°00’W] (8 S paratypes) ; same locality, 4.i.1956, W. Kempf [col.], # 1552, (1 S paratype) ; same locality, 08.i.1956, W. Kempf [col.], # 1560, (2 S paratypes) ; Campos do Jordão , 16.x.1956, W. Kempf [col.], # 1601 [22°44’S, 45°34’W] (1 S paratype) ; Itatinga, 19.x.1991, B.H. Dietz col. mata litter [23°07’S, 48°35’W] (5 S); Jacupiranga, xi.1963, F. Plaumann [col.], # 4089 [24°42’S, 48°00’W] (1 S); [São Bernardo do Campo] Estrada Velha São Paulo – Santos [Old São Paulo – Santos Highway ], 08.viii.1960, W. Kempf [col.] [23°49’S, 46°28’W] (6 S paratypes) .

Comments: In the Rastratus species-group , O. reticulatus workers present exclusively the integument almost entirely covered by irregular somewhat undulate costulae on the head disc, mesosoma and dorsal petiolar peduncle ( Kempf, 1974: Figs. 23, 24, 25 and 26).

Oxyepoecus reticulatus has been registered in several localities in South and Southeastern Brazil from Minas Gerais to Santa Catarina states ( Fig. 8 ), more commonly in relatively dry forests.

Figures

FIGURE 4: Scanning electron micrograph of the workers of O. reticulatus; a) head in full-face view; b) mesosoma in profile view; c) Petiole and postpetiole in dorsal view.

FIGURE 8: Map of distribution of O. reticulatus and O. rosai.