Temnothorax megalops (Hamann & Klemm, 1967)

Prebus, Matthew, 2015, Palearctic elements in the old world tropics: a taxonomic revision of the ant genus Temnothorax Mayr (Hymenoptera, Formicidae) for the Afrotropical biogeographical region, ZooKeys 483, pp. 23-57 : 32-33

Taxon classification Animalia Hymenoptera Formicidae

Temnothorax megalops (Hamann & Klemm, 1967) Figs 3a and c, 7, 8

Leptothorax megalops : Hamann and Klemm 1967: 417.

Temnothorax megalops (Hamann & Klemm): Bolton 2003: 271

Type material.

Holotype worker, SUDAN, Wadi Halfa, feuchter Graben, 28.I.1962 (H. Hamann & W. Klemm) (NHMW: CASENT0712601) [examined]. Paratype, 1 dealate queen with same data as holotype (NHMW: CASENT0712600) [examined].

Diagnosis.

The following character combination clearly separates Temnothorax megalops from the other Afrotropical Temnothorax species: Antennal scapes short, distinctly failing to reach the posterior margin of the head; compound eyes large; post petiole trapezoidal in dorsal view, widest at the anterior 1/5 of the segment; metanotal groove present; head subrectangular; posterior margin of head shallowly but distinctly impressed; setae on the posterior margin of the first gastric tergite separated by about their own length; pilosity of antennal scapes short and adpressed.

Worker measurements

(n = 1). EL 0.174; FRS 0.175; HL 0.636; HW 0.465; IOD 0.376; IOcD N/A; MD 0.141; PH 0.183; PL 0.208; PPH 0.178; PPL 0.127; PPW 0.192; PTW 0.139; PW 0.327; SL 0.505; SPST 0.145; WL 0.728.

Indices: CI 73.1; DPeI 66.8; DPpI 151; LPeI 114; LPpI 71.3; OI 37.4; PeNI 42.5; PpNI 58.7; PPI 138; PSLI 22.8; SI 79.4.

Worker description.

Head subrectangular, longer than wide (CI 73.1); head sides parallel, but converging toward the mandibular insertions anteriorly beyond the level of the antennal insertions in full-face view; posterior head margin with a broad, shallow median impression; posterior corners of head broadly rounded. Anterior clypeal margin convex and entire, with the median clypeal lobe projecting slightly beyond the lateral clypeal lobes. Frontal carinae poorly developed: extending posteriorly about one-quarter the length of the compound eye. Antennae 12-segmented, antennal scapes relatively short, failing to reach the posterior margin of the head (SI 109). Eyes large (OI 37.4); 11 ommatidia in the longest row.

Mesosoma relatively compact (WL 1.14 times HL); promesonotal suture absent. Metanotal groove shallowly but distinctly impressed; visible as a shallow concavity in lateral view, and as a narrowing of the dorsal surface of the mesosoma in dorsal view. Propodeal declivity steep. Propodeal spines blunt and relatively short (PSLI 22.8); propodeal lobes small and rounded.

Petiole without a differentiated peduncle. In profile, the anterior face of node forming a shallow concavity anteriorly as it joins the anterior portion of the petiole. Petiolar node in profile relatively low and cuneate (LPeI 113), junction of anterior and posterior faces forming a 90° angle; without differentiated dorsal and posterior faces. In dorsal view petiole elongate (DPeI 66.8). Postpetiole in profile with proximal half of dorsal margin evenly rounded, and distal half forming an even declivity; nearly equal in height to petiolar node and laterally compressed (LPpI 71.3). In dorsal view postpetiole trapezoidal and wider than long (DPpI 151), widest at 1/4 of the total postpetiole length from anterior margin, and 1.4 times wider than petiole (PPI 138).

Mandibular sculpture: longitudinally irregularly striate along entire length. Clypeus smooth and shiny, bearing 5 longitudinal rugae, with median ruga strongly developed and running posteriorly from the anterior clypeal margin to the level of antennal insertions before weakening. Cephalic dorsum smooth and shiny with weak, closely spaced longitudinal rugae, becoming sparse medially. In profile, gena anterior to the compound eye reticulate but otherwise similar to sculpture on dorsum. Sculpture of mesosoma in dorsal view punctate, becoming weak on pronotum, with overlying weak, longitudinal rugae which become stronger in the metanotal suture. Space between propodeal spines with a single fine, arcuate transverse carina, which divides the propodeal dorsum from the declivity. Propodeal declivity shallowly punctate and shining. In profile, mesosoma predominantly longitudinally rugose; humeri weakly reticulate, propodeum finely punctate. Petiole and postpetiole finely punctate, with a couple of weak longitudinal rugae visible on dorsum of postpeiole. Gaster smooth and shining except for small, widely spaced piligerous punctures.

Mandibles and ventral region of the head with a short, fine yellowish pubescence. Posterior margin of clypeus with two pairs of short, stout setae flanking each side of the median lobe. Frontal carinae with one stout seta each, located at the level of the anterior margin of the compound eye. Posterior margin of the head equipped with several short, blunt-tipped setae. Anterior clypeal margin with two pairs of long setae flanking the median carina. Scapes with abundant, short, subdecumbant pilosity. Propleurae with several short, sharp-tipped setae. Pronotal “neck” and pronotal humeri, and procoxae free of pubescence. Dorsal surfaces of mesosoma, waist segments and gaster with uniformly erect, short, sparse and blunt-tipped bristle-like setae; their bases spaced from each other by more than the length of the setae which arise from them. Ventral surfaces of the post-petiole and gaster free of pilosity.

Queen measurements

(n = 1). EL 0.205; FRS 0.204; HL 0.661; HW 0.506; IOD 0.407; IOcD 0.135; MD 0.147; PH 0.21; PL 0.233; PPH 0.177; PPL 0.153; PPW 0.241; PTW 0.177; PW 0.422; SL 0.536; SPST 0.188; WL 0.904.

Indices: CI 76.6; DPeI 76; DPpI 158; LPeI 111; LPpI 86.4; OI 40.5; PeNI 41.9; PpNI 57.1; PPI 136; PSLI 28.4; SI 81.1.

Queen description.

Head subrectangular, longer than wide (CI 76.6); head sides parallel, but converging toward the mandibular insertions anteriorly beyond the level of the antennal insertions in full-face view; posterior head margin with a broad, shallow median impression and posterior corners of head broadly rounded. Anterior clypeal margin convex and entire, with the median clypeal lobe projecting slightly beyond the lateral clypeal lobes. Frontal carinae poorly developed: extending posteriorly about one-half the length of the compound eye. Antennae 12-segmented,antennal scapes relatively short, failing to reach the posterior margin of the head (SI 106). Eyes large (OI 40.5); 13 ommatidia in the longest row. Three ocelli present.

Body more massive than the worker; mesosoma somewhat elongate (WL 1.37 times HL). Scutum and scutellum forming an even, flat surface in profile, broken only by the suture between the two tergites. Propodeal declivity steep. Propodeal spines blunt and slightly longer than in the worker (PSLI 28.4); propodeal lobes small and rounded.

Petiole without a differentiated peduncle. In profile, the anterior face of node forming a shallow concavity anteriorly as it joins the anterior portion of the petiole. Petiolar node in profile relatively low and cuneate (LPeI 111), junction of anterior and posterior faces forming a 90° angle; without differentiated dorsal and posterior faces. In dorsal view petiole elongate (DPeI 76). Postpetiole in profile with proximal half of dorsal margin evenly rounded, and distal half forming an even declivity; nearly equal in height to petiolar node and laterally compressed (LPpI 86.4). In dorsal view postpetiole trapezoidal and wider than long (DPpI 158); widest in the anterior 1/4, and 1.4 times wider than petiole (PPI 136).

Mandibular sculpture: longitudinally irregularly striate along entire length. Clypeus smooth and shiny, bearing 5 longitudinal rugae, with median ruga strongly developed and running posteriorly from the anterior clypeal margin to the level of antennal insertions before weakening. Cephalic dorsum with closely spaced longitudinal rugae, extending the entire length of the head, but becoming weak between the compound eyes and ocelli. In profile, gena anterior to the compound eye strongly reticulate. Scutum and scutellum with longitudinal rugae; propodeum reticulate. Space between propodeal spines with a single strong, arcuate transverse carina, which divides the propodeal dorsum from the declivity. Propodeal declivity with longitudinal rugae. In profile, mesosoma predominantly longitudinally rugose; anterior of pronotum reticulate; sculpture weakened on mesopleuron. Petiole and postpetiole finely punctate, with longitudinal rugae on dorsum of postpeiole. Gaster smooth and shining except for small, widely spaced piligerous punctures.

Mandibles and ventral region of the head with a short, fine yellowish pubescence. Posterior margin of clypeus with two pairs of short, stout setae flanking each side of the median lobe. Frontal carinae with one stout seta each, located at the level of the anterior margin of the compound eye. Dorsal surface of head equipped with several short, blunt-tipped setae. Anterior clypeal margin with two pairs of long setae flanking the median carina. Scapes with abundant, short, subdecumbant pilosity. Propleurae with several short, sharp-tipped setae. Pronotal “neck” and pronotal humeri with short, stout and sparse setae.Procoxae with short, thin and sparse setae. Dorsal surfaces of mesosoma, waist segments and gaster with uniformly erect, sparse and blunt-tipped bristle-like setae which is longer than in the worker. Ventral surfaces of the post-petiole free of pilosity; ventral surface of gaster with short, fine, yellowish pilosity.

Male.

Unknown

Color.

Worker:Yellow overall with gaster slightly infuscated at the posterior margin of the first tergite.

Queen: Same as worker.

Distribution and ecology.

Known only from the type material, which was collected from Wadi Halfa, Sudan.