Dinoponera lucida Emery 1901

Mayron E Escárraga, John E Lattke & Celso O Azevedo, 2017, Discovery of the Dinoponera lucida male (Hymenoptera, Formicidae), a threatened giant ant from the Atlantic rain forest, Zootaxa 4347 (1), pp. 128-136 : 130-134

Dinoponera lucida Emery 1901

( Figures 1–3 )

Dinoponera grandis subsp. lucida Emery 1901:48

Dinoponera lucida Emery. Raised to species by Kempf 1971:376

Male diagnosis. Body bicolored: head, mesosoma, and petiole brown; scape, legs and gaster ferruginous brown. Lateral ocelli protruding beyond posterior cephalic margin in dorsal view of the head; abdominal tergum VIII shaped as acute triangular; body with abundant long yellow hairs.

Measurements: (n=8) HL= 1.90–2.10, HW1= 1.58–1.86, HW2= 2.22–2.44, MAL= 0.14–0.24, MDL= 0.48– 0.56, SL= 0.60–0.76, PDL= 0.20–0.24, A3L= 1.38–1.50, A4L= 1.40–1.58, AAL= 1.34–1.46, EL= 1.16–1.28, EW= 0.74–0.80, MOD= 0.34–0.40, OOD= 0.32–0.42, LOD= 0.32–0.38, WL= 5.83–6.33, MLL= 1.14–1.48, MLW= 2.00–2.26, MTL= 2.52–2.68, MTW= 2.56–2.84, PFL= 3.68–3.96, MFL= 4.72–5.08, FWL= 13.3–15.0, HWL= 10.0–11.7, PTH= 1.24–1.48, PTL= 1.66–1.82, PTW= 0.98–1.10, GL= 7.33–8.17, TBL= 17.6–18.7, CI= 74.7–93.9, CS= 1.66–1.95, SEI= 168–200, SI= 32.3–46.5, EI1= 59.7–63.8, EI2= 98–119, MDI= 23.1–28.4, OBI= 60.2–79.3, OMI= 483–900, MNI= 1.49–1.84, MTI= 101–184 FI= 76.7–80.5, PTI= 70–87.1

Cephalic capsule ovoid in dorsal view, wider than long including compound eyes; posterior cephalic margin forming blunt angle interrupted by lateral ocelli close to its apex; lateral head margin convex, formed by compound eye. Clypeus protrudes posteriorly between compound eyes; anterior margin bordered by narrow, translucent lamella; lamella medially straight to weakly convex, laterally convex; surface of clypeal disc very convex, epistomal sulcus posteriorly convex and weakly impressed, separating clypeus from weakly elevated but flattened frontal triangle that extends posterad between antennal sockets; anterior tentorial pit large and easily discernible. Frontal carina reduced to faint and short elevated line, median torular arch shaped as weak posteromedian convex lobe that leaves antennal condyle completely exposed, lateral torular arch simple; antennal socket located at cephalic mid-length, as measured from anterior clypeal margin to posterior head margin, separated from other socket by distance shorter than median ocellus diameter (MOD= 0.34–0.40). Compound eye large and bulging (EI2= 98–119), occupying whole lateral cephalic margin (OBI= 60.2–79.3), dorsomedial margin weakly emarginate; ocelli large and protruding, approximately equal in sized, lateral ocelli closer to anterior ocellus than to each other and separated from compound eye by a distance similar to its diameter (OOD=0.32–0.42). Antenna longer than mesosoma, 13-segmented; scape length approximately half of first flagellomere and shorter than EL; pedicel length approximately one-third that of scape, surface smooth; flagellum filiform, punctate. Palpal formula 4,3 (in situ count); labrum, in dorsal view, lateromedially narrower than labium, weakly projecting as transverse, anteriorly emarginate structure with convex dorsal surface. Mandible slightly shorter than antennal scape, apically rounded, lacking teeth, surface smooth and shiny, with basal, flattened lateral expansion. Cephalic sculpture mostly shining with scattered small, piligerous tubercles; weak longitudinal striae present between ocelli and antenna.

Mesosoma in lateral view with anterior pronotal margin forming brief overhang above head, narrow posterior shelf present at promesonotal junction; mesoscutum convex; mesoscutellum strongly convex; metanotum brief and strongly convex; propodeal dorsal margin straight to weakly convex in profile view, forming smooth continuity with broadly convex declivitous margin.

Pronotum trapezoid in lateral view, posterolateral corners blunt and slighted lifted; mesopleural sulcus oblique, deeply impressed, scrobiculate, mesopleural pit directed ventrally; spiracular sclerite oval, directed anterolaterally; metapleuron medially constricted, with conspicuous and deep pit medially located near metapleural-propodeal suture; metapleural-propodeal suture broad and shallow but well-defined; propodeal spiracle slit-shaped. In dorsal view, pronotal posterior margin broadly concave, lateral lobe protruding, mesoscutum with three longitudinal carinae: one anterior median notal carina and two lateral parapsidal lines; notauli absent, mesoscutum smooth and shining; scutoscutellar sulcus scrobiculate, mesoscutellum hexagonal, disc smooth and shining; metascutellum transversally rectangular with transverse striae. Mesosoma mostly smooth and shining except for metanotum and irregular minute raised areas on propodeal declivity. Protibial calcar pectinate with small basal lamella (= “velum of calcar”), probasitarsus with basal comb; meso- and metatibia each with long pectinate spur and simple short spur; all basitarsi long, each about same length of its corresponding tibia; tarsal claws with preapical tooth; arolium well-developed.

Fore wing with pterostigma, abscissae C, Sc+R, R, Rs, Rs+M, M+Cu, M, Cu, and A present; crossveins 2r-rs, 2rs-m, 1m-cu, cu-a present. Cells Costal+Subcostal, Basal, Subbasal, Marginal, Submarginal 1, Submarginal 2, Discal, Subdiscal present. Rs weakly curved anterad R; M and Cu curved posterad, without reaching posterior margin. Crossvein cu-a far from wing base, near discal cell ( Fig. 3A). Hind wing with abscissae R+Rs, Rs, M+Cu, M, Cu, and A present; crossveins 1rs-m and cu-a present; no abscissae reach posterior margin; segment of M+Cu posterior to cu-a twice as long as segment of M anterior to rs-m; 1rs-m almost twice longer than cu-a, jugal lobe present ( Fig. 3B).

Petiole rounded in lateral view, anterior margin more broadly convex than posterior margin, petiolar spiracle relatively small, oval, anteriorly located. Petiole rectangular in dorsal view, longer than broad with anterior cervix developed, posterior corner rounded, spiracle laterally protruding; articulation with gaster well-defined. Gaster smooth and shiny, with well-marked constriction between abdominal segments III and IV; spiracles on tergites III– V exposed; stridulitrum present on abdominal pretergite IV; abdominal tergum VIII ending in very acute triangle almost forming a spine ( Fig. 1B ), cercus about as long as fourth protarsomere, club-shaped, bearing many long hairs issuing from small piligerous tubercles; abdominal sternum IX apically truncate; telomere rounded; penisvalva with ventral margin serrated.

Head covered with scattered, long yellow hairs, longest hairs on posterior part of head; clypeus bearing long, subdecumbent, anteriorly projecting hairs that surpass extended labrum, posterior region of clypeus and frons with shorter appressed yellow hairs. Antenna with many short, appressed and subdecumbent hairs, some longer erect hairs present on first three flagellomere, each about as long as pedicel. Maxillary palp segments III and IV with erect hairs; labrum bearing short erect setae. Dorsum of mesosoma densely covered with yellow decumbent and erect hairs, hairs longer on pronotum and propodeum; pilosity scarce on sides of pronotum and anterior portion of mesopleuron; setae on propodeum long, about same length of mandible. Wings covered with short decumbent hairs. Petiole densely covered with erect, yellow hairs, longer than propodeal hairs. Gaster covered with many subdecumbent yellow hairs.

Head, mesosoma, and petiole brown; scape, pedicel, mandible, labrum, maxilla, labium, legs, and gaster ferruginous brown; flagellum mostly dark brown ( Fig. 1A ). Discrete light blue iridescence visible on different body parts depending upon light source used.

Distribution ( Figure 4). Dinoponera lucida is endemic to the Atlantic Forest of Brazil, recorded from the states of Bahia, Espírito Santo, Minas Gerais, and São Paulo, with most records in Espírito Santo and Southern Bahia. The most northern record is from Ilheus (Bahia) and the southernmost record is from Cruzeiro (São Paulo). There is a single record from São Paulo by Kempf (1971).

Figures

FIGURE 1. Dinoponera lucida male habitus (A), cabeça (B), and mesosoma (C).

FIGURE 2. Dinoponera lucida male abdominal tergum VIII (A) and penisvalva (B).