Oxyepoecus rastratus ( Mayr, 1887 )

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 : 299-303

Oxyepoecus rastratus ( Mayr, 1887)

( Figs. 3 a-c, 7)

Monomorium rastratum Mayr, 1887:615-6 (s Brazil).

Monomorium (Martia) rastratum : Forel, 1912: 3 (s Brazil); Borgmeier, 1928:65 (key).

Martia rastrata : Kusnezov, 1952: 722.

Oxyepoecus rastratus : Ettershank, 1966: 146 (transfer to Oxyepoecus ); Kempf, 1972:173 (catalogue); Kempf, 1974:498 (description of gyne and male); Bolton, 1995:302 (catalogue).

Monomorium (Martia) rastratum var. luederwaldti : Forel, 1913:219 (s Brazil); Luederwaldt, 1918:43; Luederwaldt, 1926:275 (biology); Kempf, 1974:498 (synonymy).

Martia rastrata var. luederwaldti : Kusnezov, 1952:722.

Oxyepoecus rastratus var. luederwaldti : Ettershank, 1966:146 (transfer to Oxyepoecus ); Kempf, 1972:173; Kempf, 1974: 498. Bolton, 1995:301 (catalogue).

Worker: t.l. = (2.20-2.80); h.l. = (0.52-0.65); h.w. = (0.43-0.55); s.l. = (0.30-0.40); m.l.e. = (0.09-0.13); m.w.pr. = (0.32-0.40); a.l. = (0.60-0.80); h.f.l. = (0.36-0.48); m.w.p. = (0.18-0.25); m.w.pp. = (0.21-0.32); c.i. 76-84. Reddish yellow to chestnut brown. Dorsum of head densely costulate, costulae attain laterally compound eye and posteriorly the vertexal margin; the median apron of clypeus smooth and shining; dorsum of pronotum and mesonotum regularly costulate; mesopleuron, metapleuron and side of propodeum densely and longitudinally costulate; basal and declivous faces of propodeum equally densely but transversally costulate (approximately 20 costulae on basal face); peduncle of petiole finely and weakly punctate dorsally and on sides. Abundant, long (subequal to last antennal club segment), suberect hairs on head, dorsum of mesosoma, petiolar and postpetiolar nodes, and gaster; shorter decumbent hairs on head, inclined mesad and dorsad on head sides.

Head in Fig. 3a (f.f.v.): Mandible with basal border shorter than chewing border, and with deep and broad triangular cleft between basal and the subbasal teeth; clypeus anterior tooth laterally with blunt denticle. Frontal carina short, posteriorly expanded laterad, ending posteriorly before level of anterior orbit of eye; maximum width between outer edges of carinae more than one fourth head width. Compound eye with 5-7 facets r.g.d., total number of ommatidia close to 15. Scape relatively long, but fails to reach vertexal corner when laid back over head, by circa twice apical scape width. Funicular segment I longer than VIII, segments II-VII distinctly broader than long, VIII and IX as long as broad. Vertexal margin straight

Mesosoma in Fig. 3b (p.v.). Promesonotum evenly convex. Shoulders somewhat rounded, gently angulate at anterolateral corner. Metanotal groove shallow to absent (p.v.), metanotal suture indistinct. Basal face of propodeum posteriorly with vertical or oblique tooth. Declivous face laterally carinate.

Petiolar node, scalelike, compressed antero-posteriorly, rounded above; ventrally acute subpetiolar process with prominent blunt tooth points anterad, reaching one fifth of petiolar length; ventral margin of subpetiolar process slightly sinuous, when seen from side. Postpetiolar node broad, shorter than petiolar node (p.v.); subpostpetiolar process shaped as transverse crest, triangular in side view.

Gyne:t.l. = 2.2-2.8; h.l. = 0.52-0.65; h.w. = 0.43-0.55; s.l. = 0.30-0.40; m.l.e. = 0.09-0.13; m.w.pr. = 0.32-0.40; a.l. = 0.60-0.80; h.f.l. = 0.36-0.48; m.w.p. = 0.18-0.25; m.w.pp. = 0.21-0.32; c.i. 76-84. Similar to worker with usual caste differences. Scutum and scutellum finely, densely and regularly longitudinally costulate. Basal face of propodeum transversely costulate, with circa 16 costulae. Posterior third of mesopleuron, the metapleuron and sides of propodeum horizontally to obliquely very finely costulate. Eye width 11-13 facets (r.g.d.), exceeding oculomalar distance, and total number of ommatidia from 60 to 100. Ocelli of similar size, their diameter equal to minimum scape width; pronotal shoulder distinct; propodeal tooth stout and prominent. Wings slightly infuscated, venation as usual in genus. The only winged specimen seen has small discoidal cell, and an extra-vein arising from junction of r-m with Rs and extending apicad between Rs and M.

Male: t.l. = 2.9; h.l. = 0.51; h.w. (eyes included) = 0.60; s.l. = 0.12; m.l.e. = 0.24; m.w.pr. = 0.60; a.l. = 0.93; h.f.l. = 0.58; m.w.p. = 0.19; m.w.pp. = 0.24. Color fuscous brown; mandible, antenna, apical half of tibiae, tarsomeres, tip of gaster testaceous. Head finely yet sharply reticulate-punctate, opaque. Sides of pronotum and mesopleuron smooth and shining, the latter vestigially costulate on posterior margin. Metapleuron and propodeal lateral face horizontally costulate. Scutum nearly smooth and shining, indistinctly sculptured. Scutellum superficially, finely, longitudinally costulate-striate. Basal face of propodeum weakly reticulate-rugose. Declivous face weakly reticulate-rugose, shining. Petiole, postpetiole and gaster smooth and shining, except punctate petiolar peduncle. Legs, especially tibiae and tarsomeres, as well as antennae sharply punctatepunctate and opaque. Mandible with 4 well developed and regularly spaced teeth. Frontal carinae absent. Clypeus transversely strongly convex, little protruding anteriorly. Propodeum bluntly tuberculate, not dentate.

Examined material: BRAZIL: Espírito Santo: Santa Teresa, Estação Biológica Santa Lúcia (19°58’S, 40°32’W), 20-24.i.2002, Shoereder, J.H. and Ribas, C.R. cols, Winkler # 17 and 39 (3 S) ; Minas Gerais: Serra do Caraça [20°04’S, 43°24’W], 1380 m, xi.1961, Martins & Silva col., K. Lenko leg. # 2390 (5 S, 2 T, 1 U); Itabirito, mina, Várzea do Lopes , 18-25.iv.2007, Andrade, R. col. (1 S) ; Paraná: Tunas, Parque das Lauráceas (24°51’S, 48°43’W), 21-29.ii.2001, [R.R.] Silva and [F.] Eberhardt cols., transecto 1 Winkler 07, 30 and 44 (5 S); Morretes , Parque Estadual do Pau-Ôco (25°34’S, 48°53’W), 06-11.v.2002, [R.R.] Silva and [F.] Eberhardt cols. Winkler 03, 16, 17, 21, 26 and 53 (5 S) (1 S CASC, 1 S AMNH) ; Rio de Janeiro: Itatiaia , i.1956, Borgmeier col. [22°23’S, 44°37’W] (1 S); Santa Maria Madalena, P [arque] E[stadual] do Desengano (21°58’S, 41°57’W), x.2002, Mayhé, A. & Veiga-Ferreira, S. cols, Winkler # 29 and 43 (2 S); Teresópolis, P [arque] N[acional] S[erra] dos Órgãos (22°25’S, 43°04’W), 23-27.xi.1999, Rocha [R.P.], Dietz [B.H.], Silva [R.R.] [8 S (one covered with gold for SEM), 1 t] ; Santa Catarina: Abelardo Luz (26°33’53”S, 52°19’42”W), 20.ix.1999, Silva, [R]ogério [R]osa col. (1 S); Blumenau, P[arque] E[stadual] das Nascentes (27°06’15”S, 49°09’14”W), 20-27.x.2000, Silva, R.R. and Eberhardt, F. cols (1 S) ; Seara (27°09’S, 52°18’W), v-xii.1998, Rogério R. Silva col. (1 S); Nova Teutônia [27°11’S, 52°23’W], iv.1954, F. Plaumann leg. # 8111 (1 S); same locality, vi.1960, same collector, # 8081 (6 S); same locality, vi.1960, same collector, # 8327, (1 S); same locality, vi.1960, same collector, 300 m- 500 m Kempf det. in [19]74 (1 S); same locality, vii.1960, same collector, # 3543 (4 S and 2 T); same locality, vi.1972, same collector, # 8081 [27°11’S, 52°23’W] (3 S); São Bento do Sul, A [rea] [de] P[roteção] A[mbiental] Rio Vermelho , 30.iii-04.iv.2001, Silva, R.R. and Eberhardt, F. cols., [26°21’51”S, 49°16’16”W] (2 S); São Bonifácio, P [arque] E[stadual] Serra do Tabuleiro , 08-13.iii.2004, Silva, R.R.; Dietz, B.H. and Albuquerque, N.L. cols., Winkler # 06, 13, 21 and 23 [27°49’06”S, 48°54’41”W] (5 T and 4 S) (1 S CECL, 1 S CPDC, 1 S MIZA) ; São Paulo: Botucatu, 01.ix.1986 / 13.vii.1987 / 07.xii.1987, Forti, L.C. and Rinaldi, I.M.P. cols. [22°53’S, 48°26’W] (4 S /1 S / 1 S); Cunha, P [arque] E[stadual] Serra do Mar, 21-22.iv.2001, A.A. Tavares & R.R. Silva cols Winkler # 48 [23°15’03”S, 45°00’26”W] (1 S); Estr. [ada] S. Paulo-Curitiba km 40, v.1960, W.W. Kempf col. [23°53’S, 46°58’W] (2 S) ; São Paulo, [Serra da] Cantareira, 01.iii.1959, [W.W.] Kempf & [Vitor dos] Santos leg. # 2990 [23°56’S, 47°02’W] (5 S); Salesópolis , Est [ação] Biol [ógica] [de] Boracéia , 02.vi.1961, Lenko, K. col. # 1791 [23°31’S, 45°50’W] (8 S); Salesópolis , Est [ação] Biol [ógica] [de] Boracéia , ii.1967, Brown, W.L. Jr. [col.], wet forest 850 m [23°31’S, 45°50’W] (4 S); same locality, v.1971, same collector [col.] # 6352 [23°31’S, 45°50’W] (5 S); Salesópolis, Est [ação] Biol [ógica] [de] Boracéia, 03-05.i.1996, Brandão [C.R. F.], Agosti [D.], Diniz [J.], Silvestre [R.] and Yamamoto [C.I.] col. (2 S) (1 S ICNC, 1 S LACM, 1 S USNM); S[ão] J[osé] do Barreiro, S [erra] da Bocaina, 01.v.1995, B[odo] H[asso] Dietz. [col.] [22°39’S, 44°33’W] (2 S); Salto Grande, xi.1911, H. Luederwaldt leg. # TB 2687 [22°56’S, 49°58’W] (3 S syntypes of Martia rastratus var. luederwaldti For. ); Tapiraí, 08-14.i.2001, Silva, R.R. and Eberhardt, F. cols., Winkler # 02, 10 and 33 [24°01’55”S, 47°27’56”W] (5 S). Paraguay: Canindeyù; Res [erva] Nat [atural] Bosque Mbaracayù, Jejuimi, 02.v.1996, A. Wild com (# 0129) (24°06’S, 55°30’W) (5 S); Pastoreo, 03.x.1974, P. Duelli [col.] # 399 [25°23’S, 55°50’W] (3 S) .

Comments: The exclusive character of the workers of O. rastratus in relation to other species in the group is the costulate sculpture between the frontal carinae, which reaches posteriorly the vertexal margin and laterally the compound eyes ( Kempf, 1974: Figs. 01, 10, 13, 19, 40, 41 and 42).

Oxyepoecus rastratus is one of the more abundant species in the MZSP collection, being the unique to have male known. Its distribution includes localities throughout the South (Paraná and Santa Catarina states) and Southeastern Brazil (Espírito Santo, Minas Gerais, Rio de Janeiro and São Paulo states), and two localities in Eastern Paraguay, as in Fig. 7 .

Figures

FIGURE 3: Scanning electron micrograph of the workers of O. rastratus; a) head in full-face view; b) mesosoma in profile view; c) Petiole and postpetiole in dorsal view.

FIGURE 7: Map of distribution of O. plaumanni and O. rastratus.