Pheidole praeusta

The nests of praeusta found by Forel at Barranquilla and Dibulla had a unique structure. The nest entrance of each was a convoluted slit surrounded by a narrow elevated earthen wall, 2 cm high off the level of the surrounding soil, 4 to 6 cm in diameter, and turning outward toward the upper rim, and overall “resembling the calyx of a large monopetalous flower.” Forel did not comment on the matter, but the praeusta entrance and superstructure are remarkably similar to the fortified cerumen nest entrances of some meliponine bees. (Wilson 2003)

Identification
See the description in the nomenclature section.

Distribution based on Regional Taxon Lists
Neotropical Region: Colombia.

Worker
Minor

Nomenclature

 * . Pheidole praeusta Roger, 1863a: 197 (s.) COLOMBIA.
 * Forel, 1901e: 361 (w.).
 * See also: Wilson, 2003: 340.
 * amata. Pheidole amata Forel, 1901e: 360 (s.w.) COLOMBIA.
 * Junior synonym of praeusta: Guerrero et al., 2022: 325.
 * See also: Wilson, 2003: 651.

Type Material

 * Pheidole praeusta: Holotype soldier, "Island", Colombia, 1820 [ CASENT0915435] (Wilson, 2003; Guerrero et al., 2022).
 * Pheidole amata: Lectotype soldier, Orihueca, Río Frio, Magdalena, Colombia [, CASENT0908158] (Wilson, 2003; Guerrero et al., 2022).

Description
From Wilson (2003): A member of a complex of Pheidole species, with giant majors and short bristly hair, in the larger fallax group comprising Pheidole astur, Pheidole oxyops, Pheidole praeusta and Pheidole trageri; praeusta is distinguished among them by the following combination of traits.

Major: rugoreticulum lacking on head; carinulae immediately next to the midline of the dorsal surface of the head reach the occiput; occipital lobes smooth and shiny; mesonotal convexity prominent; propodeal spines small, thin, and vertical to the basal propodeal face; postpetiolar node seen from above elliptical, with angulate lateral margins; anterior and lateral margins of pronotal dorsum transversely carinulate; propodeum completely carinulate.

Minor: occiput narrowed somewhat, with nuchal collar; dorsal margin of petiolar node bidentate in rear view; propodeal spine reduced to denticle; pronotum entirely smooth and shiny.

MEASUREMENTS (mm) Holotype major (Mus. National Hist. Nat. Paris): HW 2.34, HL 2.78, SL 1.10, EL 0.30, PW 0.92. Minor (Barranquilla, Colombia): HW 0.60, HL 0.78, SL 0.96, EL 0.16, PW 0.42.

COLOR Major: concolorous reddish yellow (“orange”).

Minor: body reddish brown except for gaster, which is dark brown.



'''Figure. Upper: major. Lower: minor. COLOMBIA: Barranquilla, col. Auguste Forel. Major compared with holotype major in, Paris; the specimen is labeled “Island, Colombia, 1820” and lacks the waist and gaster. Scale bars = 1 mm.'''

Pheidole amata

From Wilson (2003): DIAGNOSIS Similar in various traits to Pheidole ambigua, Pheidole celaena, Pheidole fera, Pheidole germaini, Pheidole peruviana, Pheidole rutilana, Pheidole schwarzmaieri, Pheidole superba and Pheidole vomer, differing as follows.

Major: mostly reddish yellow; lower pronotal margin, upper half of mesopleuron, and sides of propodeum bearing curved carinulae, those on mesopleuron S-shaped; eye bean-shaped, with concave ventral border; clypeus prominent and long in side view but lacking any process; head subrectangular; occipital cleft deep; humerus in dorsal-oblique view prominent, subangulate; petiolar node thin in side view, and broad, elliptical, and marginally angular seen from above.

Minor: propodeal spine absent; occiput narrowed to a neck with nuchal collar; posterior half of mesonotum carinulate.

MEASUREMENTS (mm) Lectotype major: HW 1.54, HL 1.88, SL 0.82, EL 0.28, PW 0.80. Paralectotype minor: HW 0.56, HL 0.74, SL 0.86, EL 0.10, PW 0040.

COLOR Major: body reddish yellow except for gaster; which is plain medium brown; appendages reddish yellow. Minor: body medium brown, verging to yellow at level of clypeus; appendages medium yellow.



'''Figure. Upper: lectotype, major. Lower: paralectotype, minor. Scale bars = 1 mm.'''

References based on Global Ant Biodiversity Informatics

 * Kempf, W.W. 1972. Catalago abreviado das formigas da regiao Neotropical (Hym. Formicidae) Studia Entomologica 15(1-4).