Leptanilloides erinys, Borowiec, Marek L. & Longino, John T., 2011

Borowiec, Marek L. & Longino, John T., 2011, Three new species and reassessment of the rare Neotropical ant genus Leptanilloides (Hymenoptera, Formicidae, Leptanilloidinae), ZooKeys 133, pp. 19-48 : 27-28

Leptanilloides erinys sp. n. Figures 1 C–D3A–L

Type material.

Holotype worker: ECUADOR, Napo: Yanayacu Biological Station, −0.60°, −77.88°, 2200m, secondary cloud forest, 9 December 2009 (M. L. Borowiec #MLB091209.01) [unique specimen identifier CASENT0234603] [QCAZ]. Paratype gyne and workers: about a hundred specimens with the same data as holotype, point-mounted and in alcohol [AMNH, BMNH, CASC, FMNH, LACM, MCZC, MZSP, NMNH, QCAZ, UCDC].

Non-type material examined: 6 workers with the same data as holotype, except collection date 1 December 2009, sifted leaf litter (M. L. Borowiec #MLB091209.04) [MLBC].

Worker measurements (holotype): HW 0.31, HL 0.41, SL 0.20, MH 0.19, ML 0.50, PrW 0.22, PW 0.11, PL 0.15, AIIIW 0.20, AIIIL 0.16, AIVW 0.33, AIVL 0.24, FFeW 0.09, FFeL 0.23, HFeL 0.22, HTiL 0.26, CI 76, PI 75, MI 38.

Worker measurements and indices (11 measured): HW 0.31-0.32, HL 0.41-0.43, SL 0.19-0.21, MH 0.18-0.20, ML 0.49-0.53, PrW 0.20-0.23, PW 0.12-0.14, PL 0.15-0.17, AIIIW 0.19-0.22, AIIIL 0.14-0.18, AIVW 0.31-0.33, AIVL 0.21-0.25, FFeW 0.09-0.10, FFeL 0.23-0.25, HFeL 0.23-0.24, HTiL 0.26-0.28, CI 74-78, PI 74-82, MI 36-41.

Diagnosis.

Worker can be distinguished by combination of relatively small size, promesonotal articulation complete and articulated, abdominal segment III large relative to petiole, presence of lateroclypeal teeth, relatively heavy sculpturing, parafrontal ridges absent, flange overhanging metapleural gland opening pointed posteriorly. It is most similar to Leptanilloides sculpturata from Colombia, but can be distinguished by significantly larger size (HW ≥0.31 in erinys versus 0.20-0.26 in sculpturata), relatively broader head (CI>70 vs. 58-67) and shorter petiole (PI>74 vs. PI=70 measured in holotype). Leptanilloides erinys also differs in weaker sculpturation of head dorsum, with small foveolae separated by about their diameter (Figure 1G), while in Leptanilloides sculpturata the foveolae are separated by much less than their diameter, often contiguous (Figure 7 in Brandão et al. 1999a).

Worker description.

With characters of Leptanilloides (see Diagnosis of Leptanilloides based on worker caste, above). Head elongate and subquadrate with lateral margins nearly straight and parallel. Posterior corners rounded and posterior border weakly concave. Parafrontal ridge absent. Clypeus laterally with blunt tooth pointing outwards. Mandible short, masticatory margin with three distinct blunt teeth basally and basal margin crenulate. Basal and masticatory margin distinct, but separated by a rounded angle. Palp formula unknown. Scape short and clavate. Antennal joints submoniliform, gradually increasing in size toward apex but not forming an antennal club. Mesosoma long, slender and flattened. Pronotum with a flexible promesonotal suture. Metanotal groove absent. Propodeum unarmed. Propodeal declivity very short and rounding into the dorsal face. Propodeal spiracle round, situated posteriorly on the sclerite. Metapleural gland flange conspicuous, translucent and posteriorly pointed. Femur not conspicuously enlarged, relatively slender. Mid tibia with one simple and hind tibia with one pectinate spur. Metatibial gland absent. Petiole smaller than abdominal segment III (postpetiole) in dorsal view. Petiole rectangular, uniformly wide across its length in dorsal view and with straight sides and abdominal segment III dilating posteriorly. In lateral view, petiolar tergite posteriorly sloping, without well differentiated posterior face and without long tubulated portion posteriorly. Petiolar sternite bulging anteriorly. Abdominal sternite III evenly rounded. Metasoma relatively robust. Abdominal segments IV–VI subequal in length in dorsal view and separated by strong constrictions. Segment VII (pygidium) small and mostly concealed by the preceding segment, U-shaped.

Head with abundant deep punctures and smooth interspaces on average about equal to puncture diameter, except on sides where punctures sparser, separated by more than their diameter. Mesosoma and abdomen more finely and sparsely punctate. Laterally on lower pronotum, entire mesopleuron, propodeum and petiole fine microreticulate sculpture present. Head, body and appendages with abundant, rather coarse, short and erect hairs. Body color yellowish to brownish.

Gyne measurements and indices (1 measured): HW 0.41, HL 0.46, SL 0.20, MH 0.24, ML 0.63, PrW 0.25, PW 0.24, PL 0.20, AIIIW 0.40, AIIIL 0.23, AIVW 0.45, AIVL 0.35, FFeW 0.11, FFeL 0.26, HFeL 0.27, HTiL 0.30, CI 88, PI 118, MI 38.

Gyne description.

Subdichthadiigyne. Head rectangular, lateral borders weakly convex and posterior border distinctly concave. Compound eyes present and comprised of about ten weakly defined ommatidia, situated behind head midlength. Mandible subtriangular, masticatory margin crenulate, basal margin edentate. Clypeal apron present, small. Wingless, without any wing sclerites or wing buds. Petiole enlarged, taller than in worker and wider than long in dorsal view. Abdominal segment III broadly attached to following segments, tergosternal fusion not assessed. Petiolar and abdominal segment III spiracles located as in workers. Girdling constriction of abdominal segments IV–VI weakly developed and conspicuous only on segment IV. Tergite of abdominal segment VII (pygidium) large, not U-shaped and mostly concealed by preceding segment as in workers. Promesonotal connection present, articulated. Entire body covered with dense pubescence, more erect than in worker.

Male.

unknown.

Biology.

This species was collected in montane cloud forest habitat. Workers were first located in sifted leaf litter. After scraping leaf litter and removing root mat in an area of about 3m2, a colony was discovered ca. 5cm below ground in a single soil cavity adjacent to a root. In a mass of workers a single gyne could be seen, as well as many slender larvae. The gyne did not have an extended gaster, there were no eggs visible in the nest, and all the larvae were of approximately the same size, suggesting synchronized brood production.