A revision of the giant Amazonian ants of the genus Dinoponera (Hymenoptera, Formicidae) Author Lenhart, Paul A. Department of Entomology, Texas A & M University, 2475 TAMU, College Station, Texas USA Author Dash, Shawn T. Department of Biological Sciences, University of Texas at El Paso, 500 West University Avenue, El Paso, Texas 79968 Author Mackay, William P. Department of Biological Sciences, University of Texas at El Paso, 500 West University Avenue, El Paso, Texas 79968 text Journal of Hymenoptera Research 2013 2013-03-20 31 119 164 http://dx.doi.org/10.3897/jhr.31.4335 journal article http://dx.doi.org/10.3897/jhr.31.4335 1314-2607-31-119 10404A9C126A44C8BD485DB72CD3E3FF 632BFFBC244FFF88656EFFBEFF8DFFA7 574808 Dinoponera quadriceps Kempf Figs 4B, G, L , 5A , 6A , 10A , 11A , 12B , 13 Dinoponera quadriceps Kempf, 1971: 380, first available use of Dinoponera grandis st. mutica var. quadriceps Santschi, 1921: 84; unavailable name, BRAZIL: Pernambuco: Sao Lourenco da Mata, Tapera (NHMB, examined). Dinoponera mutica var. Mann, 1916, male Dinoponera gigantean mutica var. quadriceps Borgmeier 1937 male designated BRASIL: Pernambuca, Tapera. Dinoponera opaca Santschi, 1921. Holotype worker BRAZIL: Rio Janeiro (Goeldi) (1 w NHMB, examined); junior synonym of Dinoponera quadriceps Kempf 1975 : 344 Worker diagnosis. This species is recognized by its finely micro-sculptured integument which is not shiny ( Fig. 12B ), rounded anterior inferior pronotal corner lacking a tooth-like process ( Fig. 1E ), ventral side of the head lacking any gular striations and long/flagellate pilosity. Description of the worker. Measurements (mm) (n=17) TBL: 28.09-33.73 (30.60); MDL: 4.10-5.05 (4.53); HL: 5.23-6.04 (5.58); HW: 5.33-5.97 (5.56); SL: 5.54-6.12 (5.80); WL: 7.38-9.03 (8.20); PL: 2.26-2.68 (2.50); PH: 3.06-3.52 (3.26); PW: 1.64-1.99 (1.80); GL: 8.20-11.93 (9.80); HFL: 7.18-8.11 (7.65). A description of the worker is given in Emery 1911 , Mann 1916 , Borgmeier 1937 , Kempf 1971 . Presented below is that of Kempf (1971) : " Antennal scape notably longer than head width. Pubescence on front and vertex of head short and inconspicuous. Gular surface of head reticulate-punctate, subopaque, but lacking arcuate striae except for some cases when a few short and vestigial striae appear antero-laterally , just behind the mandibular insertion. Sides of head reticulate-punctate, subopaque. Antero-lateral corner of pronotum obtusely angulate (very seldom subdentate). Pronotal disc reticulate-punctate, subopaque, occasionally slightly wrinkled, bristle pits irregular in outline; paired swellings very faint and obsolete. Hind tarsus I longer than head length. Petiole ... of distinctive shape, the anterior surface being slightly inclined forward and often a bit excavate; anterior upper corner narrowly, the posterior corner very broadly rounded; integument minutely reticulate-punctate and subopaque; sulcus on posterior surface always distinct. Terga I and II of gaster reticulate-punctate and opaque; piligerous pits for pubescence discally greatly scattered (in a few southern specimens from Bahia State, these pits are stronger and denser, almost as in gigantea); coarse bristle-bearing pits greatly scattered: pubescence rather scarce on dorsum, denser and more conspicuous on sides. Stridulatory file on tergum II of gaster weakly developed, arising from the anterior border of acrotergite and running streak-like across the anterior half of the same (visible only when acrotergite is fully exposed; observed in five specimens) ." Male diagnosis. Males of this species are distinguished by the long fine setae of the second funicular segment ( Fig. 4G ), light brown coloration, long narrow parameres ( Fig. 9A ), volsella with two small basal teeth and lacking a lobe on the distal edge of digitus volsellaris ( Fig. 10A ). Description of the male. Total length 21mm ( Mann 1916 ) 22 mm ( Borgmeier 1937 ). A description of the male is given in Emery (1911) , Mann (1916) , Borgmeier (1937) , and Kempf (1971) . Mann (1916) described the male as follows: " Head, including the mandibles, as broad as long, very convex behind. Eyes very large and long occupying the entire sides of head, the inner border deeply emarginate; ocelli very large and convex. Clypeus convex, the anterior border truncate. Mandibles small, pointed at apex, with a small tooth at middle of inner border. Antennae a little shorter than the body; first funicular joint twice as broad as long; joints 2-11 very long, cylindrical, each slightly shorter and more slender than the preceding. Thorax [= mesosoma] robust; scutellum short, triangular, broadly rounded at apex. Epinotum [= propodeum] evenly rounded, without distinct base or declivity, unarmed. Petiole nearly twice as long as broad, narrowed in front, with nearly straight sides; in profile longer than high, flattened above ... the anterior slop gradual, more abruptly sloping behind, the antero-ventral surface with a broad, triangular projection. Gaster long and slender, the three times the breadth. Genitalia prominent; the valves board, rounded at apex; cerci long and slender ... Wings large extending almost to the tip of gaster ... Legs very long and slender ... Body and legs shining. Antennae opaque, coarsely, densely punctured; sparsely pubescent, and having much very long, fine erect hairs, which on the apical joints are shorter and confined to the tips; pubescence of apical joint more dense than the rest. Thorax (=mesosoma) with long silky pubescence, most abundant on the pleurae, and very fine re erect hairs sparsely distributed node without pubescence, but with abundant erect hairs. Gaster with a thick mat of silky pubescence, shorter and finer than that of the thorax (=mesosoma); lateral and apical portions with fine erect hairs ... Color rufous, the antennal scape and the first five funicular joints fucous. Wings lightly infuscated, veins and stigma reddish brown. Pubescence yellowish white, exempt the long antennal hairs which are black ." To this Borgmeier (1937) added that the petiole was "rounded on top", "the sting of the pygidium [=pygidial spine] long; subgential plate with apex slightly concave", and that the wings were 16mm long and "slightly yellowish". Kempf (1971) noted the dorsum of the gaster lacked standing hairs. Description of the male genitalia. Basal ring with wide, thin dorso-anterior loop structures; parameres distinctly long, narrow, rounded end, emarginated ventro-basal edge ( Fig. 9A ); cuspis volsellaris finger-like with few rounded bumps on medial face, digitus volsellaris broad cusp-like with numerous small circular bumps, 2 teeth at ventro-basal corner of volsella ( Fig. 10A ); penis valve of aedeagus with lateral arm of apodeme at anterior border, slight ventral concavity under ridge at base of apodeme, distal edge wedge-shaped, proximal ventral edge of penal valve ending in anterior facing tooth, ventral edge with large dorso-laterally curved lip with serrated edge, serrations facing laterally on either side of dorsally curved lip (similar to penis valve in Fig. 8A ). Figure 6. Schematic drawing of generalized Dinoponera male genitalia in situ ; genitalia capsule and disarticulated aedeagus, volsella and parameres. Distribution. Dinoponera quadriceps is found in the Caatingas, Cerrados, upland humid forest and Atlantic forest ( Kempf 1971 , Paiva and Brandao 1995 ) in the northeastern Brazilian states of Alagoas, Bahia, Ceara , Paraiba, Pernambuco and Rio Grande do Norte ( Fig. 13 ). Discussion . Dinoponera quadriceps as characterized by Kempf (1971) is maintained as a valid species by our analysis. Dinoponera quadriceps may be confused with Dinoponera mutica , but has a finely micro-sculptured integument which is not shiny ( Fig. 12B ), lacks gular striations and has a petiole which bulges on the dorso-anterior edge in contrast to Dinoponera mutica 's roughly microsculptured integument, striated gula and petiole with even, non-bulging corners ( Fig. 1F ). We also agree with the synonymy of Dinoponera opaca by Kempf (1975) after examination of the type. Dinoponera quadriceps and Dinoponera mutica differ in micro-sculpturing, gular striations and petiole shape. Distribution records show a distance of over 900 km between the two species, but if specimens are found with an integration of characters in the area of Tocantins and northern Goias than these species should be synonymized. Material examined. BRAZIL, ALAGOAS: Pedra (1 w, viii.1939, A Muller, AMNH); CEARA : Tiangua (1 w, 6.iv.1972, JS Bowman, MCZC); PARA : Obidos (1 w, ii.1981, CWEM); Rio Tapajoz region (1 w, viii.1983, CWEM); Santarem (1 w, 20.v.1984, CWEM); PARAIBA: Independencia (1 w, 1 m, Mann and Heath, USNM, 2 w, LACM); Joao Pessoa (4 w, 21.iv.1975, J Kesselring, CASC, 1 w, i.1976, BA Bkaul, CWEM); Joao Pessoa forest of Gargau primary forest on ground 45m(1 w, 22.i.1981, G Ekis, MCZC); RIO GRANDE DO NORTE: Baixa Verde (2 w, WM Mann, USNM, 1 w, gift of Wheeler, MCZC); Ceara-Mirim (1 w, 1 m, WM Mann, USNM); Natal (6 w, WM Mann, AMNH, LACM, MCZC, USNM); Sao Jose do Bonfim (1 w, 22.iii.1945, HT Dalinat, LACM);state not specified, North Piari (1 w, vi-vii.1944, L Parker, MCZC).