Acropyga oreithauma

Acropyga oreithauma was collected together with several individuals of the mealybug Neochavesia caldasiae (Balachowsky, 1957). This mealybug species has also been found in trophobiotic relationships with Acropyga exsanguis and Acropyga fuhrmanni (Williams, 1998; Schneider and LaPolla, 2011; LaPolla, Williams & Fan, 2017).

Identification
LaPolla, et al. (2017) - Distinctly large among the New World Acropyga (TL: 3.66-4.02); medially clypeal margin extends in a short shelf-like manner; 8 segmented antennae.

This is by far the largest species of Acropyga in the New World. There are several New World species such as Acropyga ayanganna, Acropyga decedens, Acropyga fuhrmanni, and Acropyga guianensis where workers can be as large as 2.6 mm in total length, but A. oreithauma surpasses 3.5 mm in total length and some workers were greater than 4 mm. Its overall size will easily separate it from other New World species.

Distribution based on Regional Taxon Lists
Neotropical Region: Panama.

Biology
Collected with A. oreithauma were several individuals of the mealybug Neochavesia caldasiae (Balachowsky, 1957). This mealybug species has also been found in trophobiotic relationships with A. exsanguis (Wheeler, 1909) and A. fuhrmanni (Williams, 1998; Schneider and LaPolla, 2011).

Nomenclature

 *  oreithauma. Acropyga oreithauma LaPolla, Williams & Fan, 2017: 2, figs. 1-4 (w.) PANAMA.

Worker
(n= 8) TL: 3.66-4.02; HW: 0.97-1.06; HL: 0.87-0.95; SL: 0.73-0.83; WL: 1.17-1.38; GL: 1.5-1.76; CI: 109-112; SI: 82-89.

Head: yellow to darker yellow from midpoint of posterior margin toward torulae and also darker along mandibular margins; covered in a dense layer of pubescence; head slightly wider than long; posterior margin distinctly concave medially; 3-4 erect macrosetae found on either side of the posterior margin concavity; eyes small, laterally placed about 0.25 mm from anterior margin of head; 8 segmented, incrassate antennae; scape surpasses posterior margin by about ½ length of pedicel; scapes with erect macrosetae scattered across surface and covered with a dense layer of pubescence; clypeus covered in a dense layer of pubescence, with longer macrosetae along clypeal margin; medially clypeal margin convex; mandible with 4 distinct teeth, a smaller tooth sometimes present between the 3rd and 4th tooth (counted from apical tooth back to most proximal (basal) tooth) in which case the mandible effectively has 5 teeth; when a smaller tooth not present, a diastema is present between 3rd and 4th teeth; a gap exists between the inner mandibular margin and anterior clypeal margin. Mesosoma: yellow, slightly darker along segmental margins; nota covered in a layer of pubescence, with many long erect macrosetae scattered across mesosomal dorsum; in lateral view pronotum rises steeply toward mesonotum; in lateral view, mesonotum much higher than propodeum; dorsal face of propodeum flat, with declivitous face steep and as about as long as dorsal face. Petiole and Gaster: petiole thick and erect reaching to slightly surpassing dorsal face of the propodeum; gaster yellow; covered in thick layer of pubescence, with scattered erect macrosetae throughout.

Type Material
Holotype worker — Panama: Panamá: Cerro Azul; 9.24533, -79.40209; 840 m; 24 Jan 2015; montane wet forest; under stone; J. Longino #9168. 7 paratype workers with same locality information as holotype (4 paratypes in USNM; 3 paratypes in ).

Etymology
Greek; combining form of oros (mountain) and thauma (wonder). Noun in apposition, invariant.