Leptanilloides copalinga

Delsinne et al. (2015) - The type series was found by visual search in a 15×15×15 cm soil core inspected for ants during 20 person-minutes (the soil content was examined over a white plastic board using a headlamp to facilitate ant detection), which suggests subterranean habits as observed in other Leptanilloides species. The habitat is a relatively well-preserved evergreen lower montane forest. Soil texture is clay loam; proportion of sand, silt and clay is 44%, 22%, and 35%, respectively; mean pH = 4 ± 0.2 SD (n = 24 soil samples).

Identification
Delsinne et al. (2015) - A member of the Leptanilloides biconstricta species-group. It can be distinguished from other species of this group by the combination of the following characters: masticatory margin of mandible feebly dentate, with teeth extremely minute, blunt and irregularly shaped (Fig. 3A - see Figure 3 below); lateroclypeal tooth present (difficult to observe in stereo microscopy even at high magnification due to the small size of the species but obvious in SEM; Fig 3A); head with piligerous foveolae separated by smooth interspaces equaling 2–3 diameters; reticulation on mesopleuron, metapleuron and lateral side of petiole superficial and interrupted; flange over metapleural gland opening conspicuous and sharply pointed posteriorly, resulting in a projection which surpasses propodeum declivity margin in lateral view (Fig. 3B); petiole slender in dorsal view, 52 ≤ PI ≤ 63 (Fig. 3D); and subpetiolar process straight (not distinctly bulging), with a rounded projection anteriorly (Fig. 3C).

The most similar species are L. biconstricta and Leptanilloides atlantica, which also possess a long and sharply pointed flange over the metapleural gland opening and a straight (not bulging) petiolar sternite with a rounded anterior projection. However, these two species have a deeper constriction between the postpetiole and abdominal segment IV. Besides, Leptanilloides copalinga has a petiole roughly as long as the postpetiole (longer in L. biconstricta) and its postpetiolar sternite is evenly rounded (distinctly bulging anteriorly in L. biconstricta). Finally, L. copalinga is larger than L. atlantica (Fig. 1). The other species of the L. biconstricta species-group are easily distinguished from L. copalinga by, among other characters, the shape of their petiolar sternite (bulging medially in Leptanilloides gracilis and Leptanilloides femoralis; bulging anteriorly in Leptanilloides erinys), the shape of the flange over the metapleural gland opening (short and rounded posteriorly in Leptanilloides improvisa and Leptanilloides prometea), the head sculpture (more densely foveolate in Leptanilloides sculpturata) and the lateroclypeal tooth (absent in Leptanilloides caracola).

Distribution
Known only from the type locality.

Distribution based on Regional Taxon Lists
Neotropical Region: Ecuador.

Castes
Known only from the worker caste.

Nomenclature

 *  copalinga. Leptanilloides copalinga Delsinne & Donoso, in Delsinne, et al. 2015: 8, figs. 2A-F, 3A-F (w.) ECUADOR.

Worker
Holotype (paratype 4006303): HW 0.33 (0.34), HL 0.44 (0.44), SL 0.23 (0.21), PrW 0.2 (0.22), WL 0.56 (0.57), MH 0.17 (0.17), PL 0.17 (0.18), PW 0.09 (0.11), PPL 0.16 (0.18), PPW 0.16 (0.18), AivL 0.26 (0.26), AivW 0.3 (0.33), FFeL 0.23 (0.27), FFeW 0.09 (0.11), HFeL 0.29 (0.29), HTL 0.3 (0.29), CI 75 (76.25), SI 70 (60.66), PI 51.61 (62.5), MI 30 (30.39).

With the characters typical of the genus (see diagnosis and description in Brandão et al. 1999 and Borowiec & Longino 2011) and of the L. biconstricta species-group (see diagnosis of the group above). Other characters or differences are as follows:

Head. Elongate and rectangular with lateral margin nearly straight and parallel. Posterior corner rounded. Posterior margin modestly convex, almost straight. Parafrontal ridge absent. Clypeal lamella strongly convex (Fig. 3A). Basal and masticatory margins of mandible dentate but teeth extremely minute, blunt and irregularly shaped, difficult to discern even under magnifications of about 100× (Fig. 3A). Basal and masticatory margins united by a broad convexity. Basal margin faintly crenulate. Labial and maxillary palps difficult to discern in situ but formula apparently 2,2. Hypostomal anterior border without distinct tooth. Scape when laid back failing to reach medial distance to posterior margin of head by nearly one maximum diameter.

Mesosoma. Flange over metapleural gland opening conspicuous and sharply pointed posteriorly, forming a projection which surpasses propodeum declivity margin (Fig. 3B). Femur not conspicuously enlarged, relatively slender. Midtibia with one short (i.e., half size of foretibia strigil), pectinate spur (Fig. 3F), although pectination may be difficult to observe even at high magnification. Hindtibia with one broadly pectinate spur roughly as long as strigil. Metatibial gland absent or very reduced and not visible even in SEM.

Metasoma. Long and relatively slender. In dorsal view, petiole rectangular with lateral margin slightly convex, twice as long as wide (Fig. 3D), and as long as abdominal segment III (postpetiole). Anterior face concave, posterior face straight. In lateral view, petiole height approximately ¼ smaller than height of abdominal segment III. Petiolar tergite dome-shaped, with short anterior and posterior faces, maximum height situated in posterior half. Short tubulated portion present posteriorly. Petiolar spiracle inconspicuous, not in excavation, set near anterior rim of tergite, similar in form and slightly smaller in diameter than propodeal spiracle. Subpetiolar process with ventral margin straight to slightly concave, not distinctly bulging, anteriorly forming rounded projection (Fig. 3C). Maximum height of petiolar sternite situated medially. In dorsal view, abdominal segment III (postpetiole) trapezoid, with straight, parallel anterior and posterior faces. Posterior face twice as long as anterior face. In lateral view, tergite evenly convex, without well-differentiated posterior face. Sternite evenly rounded. In dorsal view, abdominal segments IV–VI subequal in length.

Pilosity and sculpture. Mandible smooth and shiny, with few, scattered piligerous punctures. Head with abundant deep piligerous foveolae and smooth interspaces on average equaling two or three puncture diameters. Mesosoma and abdomen more finely and sparsely punctate. Fine reticulate sculpture present laterally on lower pronotum, mesopleuron, propodeum and petiole. Dorsal part of pronotum, mesopleuron, propodeum and petiole smooth and shiny. Body and appendages with abundant, short and subdecumbent to suberect hairs. Body color yellow to reddish, with head and mesosoma darker than petiole and gaster. Legs and antennae yellowish.

Type Material
Holotype. ECUADOR: Worker, Zamora-Chinchipe Prov., Copalinga Private Reserve, 1510 m, 4°4’56.6” S, 78°58’5.71” W, 2 Apr. 2010, soil sample, coll. Thibaut Delsinne and Tania Milena Arias-Penna (QCAZ, sc 4006304). Paratypes. ECUADOR: Same data as holotype: 1 worker, gold-coated for SEM (RBINS, sc 4006301); 1 pinned (MUTPL, sc 4006303); 1 worker, 96% ethanol (RBINS, sc 4006302, specimen with DNA data). GenBank accession number: KT601697.

Etymology
Name in apposition which refers to the Copalinga Private Reserve, the type locality, in honour of its owners Catherine Vits and Boudewijn de Roover to acknowledge their efforts for the conservation of Ecuadorian biodiversity.