Leptanilloides copalinga Delsinne & Donoso, 2015

Delsinne, Thibaut, Sonet, Gontran & Donoso, David A., 2015, Two new species of Leptanilloides Mann, 1823 (Formicidae: Dorylinae) from the Andes of southern Ecuador, European Journal of Taxonomy 143, pp. 1-35 : 8-12

Leptanilloides copalinga Delsinne & Donoso sp. nov.

urn:lsid:zoobank.org:act:4324B13A-500B-464C-AE3F-62BCAF95A2CC

Figs 2 A–F, 3A–F

Diagnosis

Leptanilloides copalinga sp. nov. belongs to the L. 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 ); 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 ).

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.

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 .

Measurements (in mm) and indices

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).

Description

Worker

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 ( Fig. 2 ), with head and mesosoma darker than petiole and gaster. Legs and antennae yellowish.

Gyne

Unknown.

Male

Unknown.

Distribution

Only known from the type locality.

Biology

Unknown. 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).

Remarks

This species belongs to the L. biconstricta species-group. The most similar species are L. biconstricta and L. 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, L. copalinga sp. nov. 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 sp. nov. is larger than L. atlantica ( Fig. 1 ). The other species of the L. biconstricta speciesgroup are easily distinguished from L. copalinga sp. nov. by, among other characters, the shape of their petiolar sternite (bulging medially in L. gracilis and L. femoralis ; bulging anteriorly in L. erinys ), the shape of the flange over the metapleural gland opening (short and rounded posteriorly in L. improvisa and L. prometea ), the head sculpture (more densely foveolate in L. sculpturata ) and the lateroclypeal tooth (absent in L. caracola ).

Figures

Fig. 2. Leptanilloides copalinga Delsinne & Donoso sp. nov. A–C. Paratype worker (specimen code 4006302). D–F. Holotype worker (specimen code 4006304). A, D. Habitus, dorsal view. B, E. Head in full-face view. C, F. Habitus, lateral view.

Fig. 3. Leptanilloides copalinga Delsinne & Donoso sp. nov. Paratype worker (specimen code 4006301). A. Anterior part of the head in full-face view, showing vertical and fused frontal carinae, exposed antennal socket, lateroclypeal tooth, strongly convex clypeal lamella and subtriangular mandible with minute denticles along its inner margin. B. Lower part of propodeum in lateral view, showing the long and sharp flange over the metapleural gland opening. C. Petiole in lateral view. D. Propodeum and petiole in dorsal view. E. Abdominal segment III (postpetiole) in lateral view. F. Mesotibial spur, short and pectinate.

Fig. 1. Relationship between HL and WL among workers in species of Leptanilloides and Asphinctanilloides. Specimens measured are holotypes or paratypes. Measurements are in mm. WL is called Mesosoma Length (ML) in Borowiec & Longino (2011) and Silva et al. (2013). Triangles: the two Leptanilloides described in this paper (L. copalinga Delsinne & Donoso sp. nov. and L. prometea Delsinne & Donoso sp. nov.); diamonds: Leptanilloides biconstricta species-group (La: L. atlantica, Lb: L. biconstricta, Lc: L. caracola, Le: L. erinys, Lf: L. femoralis, Lg: L. gracilis, Li: L. improvisa, Ls: L. sculpturata); dots: Leptanilloides legionaria species-group (Ll: L. legionaria, Lm: L. mckennae, Lno: L. nomada, Lnu: L. nubecula); stars: Asphinctanilloides species (Aa: A. amazon Brandão et al., 1999, Aan: A. anae Brandão et al., 1999, Am: A. manauara Brandão et al., 1999).