Acropyga donisthorpei

From LaPolla (2004) - Weber (1944) reported this species from rainforests, nesting in the leaf litter and rotten wood. It has been reported with one mealybug species belonging to the genus Neochavesia.

Identification
From Lapolla (2004):

Diagnosis - Worker: 11 segmented antennae; dorsal surface of mandible with many erect hairs; inner mandibular margin roughly parallel to clypeal margin; mandible with 5 teeth, the 3rd tooth (from apical) being much smaller than others. Queen: as in worker with modifications expected for caste. Male: 12 segmented antennae; mandible similar to worker, but with only 3 teeth; digiti plate-like, pointing ventrally. Compare with Acropyga decedens.

Workers of this species can be separated from Acropyga decedens by the rounded posterolateral corners giving the head an overall oval appearance in full frontal view. The dorsal surface of the mandible is also distinctly hairy. The inner mandibular margin and anterior clypeal margin form roughly right angles to each other, a characteristic observed only in one other New World species, Acropyga tricuspis, which is easy to diagnose because of its enlarged, square basal tooth.

A. donisthorpei is a close relative of A. tricuspis, sharing with it in males a downward bend in the dorsal margin of the penis valves, similarly shaped parameres, and in workers the oval shaped heads and similar mandibular structures.

Key to New World Acropyga Workers / Queens / Males

Distribution based on Regional Taxon Lists
Neotropical Region: Bolivia, Ecuador, Guyana, Peru.

From LaPolla (2004): This species has a wide range, stretching north from Bolivia northwest to Peru then east to Guyana, probably occupying much of tropical South America.

Nomenclature

 *  donisthorpei. Acropyga (Rhizomyrma) donisthorpei Weber, 1944: 118, figs. 9, 20, 21 (w.) GUYANA. LaPolla, 2004a: (q.). Senior synonym of oko, paludis: LaPolla, 2004a: 58.
 * oko. Acropyga (Rhizomyrma) oko Weber, 1944: 119, fig. 16 (w.) GUYANA. Junior synonym of donisthorpei: LaPolla, 2004a: 58.
 * paludis. Acropyga (Rhizomyrma) paludis Weber, 1944: 121, fig. 15 (w.m.) GUYANA. Junior synonym of donisthorpei: LaPolla, 2004a: 58.

Worker
From LaPolla (2004) - Head: brownish-yellow; head longer than broad, covered in layer of appressed hairs, with a few erect hairs along posterior margin; posterior margin entire to slightly concave medially; 11 segmented, incrassate antennae; scape fails to reach posterior margin by about half the length of the pedicel; scape covered in short, suberect to erect hairs; clypeus convex with erect hairs; mandible with 5 teeth; the 3rd tooth is typically much smaller than others; a short diastema exists between 4th and basal tooth; dorsal surface of mandible with many short (approximately 20 hairs) erect hairs, giving it a hairy appearance in full frontal view; inner mandibular margin parallel to clypeal margin. Mesosoma: brownish-yellow; pronotum in lateral view with a distinct shelf-like extension before rising steeply toward mesonotum; posterior portion of pronotum with erect hairs of varying lengths; mesonotum with many erect hairs; metanotal area distinct; propodeum rounded, with many erect hairs; declivity steep. Gaster: petiole erect, slightly concave at apex; gaster brownish-yellow; covered in appressed hairs, with scattered erect hairs throughout, especially along posterior segmental margins.

Measurements (n=6): TL: 1.86-2.23; HW: 0.479-0.537; HL: 0.553-0.602; SL: 0.381-0.43; ML: 0.525-0.602; GL: 0.715-1.08; CI: 86.62-89.2; SI: 73.7-80.72.

Queen
From LaPolla (2004) - As in worker with modifications expected for caste.

Measurements (n=1): TL: 3.89; HW: 0.612; HL: 0.641; SL: 0.531; ML: 1.02; GL: 2.23; CI: 95.48; SI: 86.76.

Male
From LaPolla (2004) - Head: brownish-yellow, brown toward apex around 3 prominent ocelli; head broader than long, covered in layer of appressed hairs; posterior margin rounded toward apex, giving head a slight triangular appearance in full frontal view; 12 segmented antennae; scape surpasses posterior margin by about half the length of pedicel; clypeus slightly convex, with erect hairs; mandible with 3 distinct teeth; diastema present between apical and 2nd tooth; inner mandibular margin, as in worker, roughly parallel to the clypeal margin. Mesosoma: pronotum collar-like, overarched by mesonotum; mesonotum flat, covered in appressed hairs; scutellum with scattered erect hairs; propodeum nearly flat with indistinct declivity. Gaster: petiole erect, slightly convex at apex; gaster brownish-yellow, lighter than head and mesosoma; covered in appressed hairs, with scattered suberect to erect hairs throughout. Genitalia: parameres taper to rounded points apically, with many erect hairs at apices; cuspi meet digiti apically; digiti plate-like, apically becoming sickle-shaped, pointing ventrally.

Measurements (n=1): TL: 2.55; HW: 0.475; HL: 0.454; SL: 0.427; ML: 0.825; GL: 1.27; CI: 104.63; SI: 89.89.

Type Material
Acropyga (Rhizomyrma) donisthorpei Weber, 1944: 118 (w.). 2 syntype workers, GUYANA: Kartabu Point (N.A. Weber) (MCZC) [examined]. The designated lectotype is a worker labeled JSL TYPE # 114.

Acropyga (Rhizomyrma) oko Weber, 1944: 119 (w.). 2 syntype workers, GUYANA: Oko River, Cuyuni tributary (N.A. Weber) (MCZC) [examined]. NEW SYNONYM.

Acropyga (Rhizomyrma) paludis Weber, 1944: 121 (w.m.). 1 syntype worker, 1 syntype male, GUYANA: HMPS, Mazaruni River (N.A. Weber) (MCZC) [examined]. NEW SYNONYM.