Probolomyrmex petiolatus

The holotype of P. petiolatus was collected among leaves and humus on the rainforest floor in Panama.

Identification
Oliveira & Feitosa (2019) - Postero-ventral lobe of petiole long and subquadrate. Subpetiolar process well developed and subrectangular. Prora and dorsal protuberance on posterior region of first gastral tergite absent.

The subrectangular shape of the subpetiolar process makes this species similar to Probolomyrmex dentinodis. However, the latter has a pair of petiolar teeth, the postero-ventral lobe of the petiole is short and rounded, and there are a prora and dorsal protuberance on the gaster.

Agosti (1994) - This species is easily recognized by the subpetiolar process.

Taylor (1965) - The worker of P. petiolatus differs from that of the sympatric Probolomyrmex angusticeps in its smaller size, with relatively broad head, much shorter scapes, and shorter, more compact petiolar node. The unknown worker of Probolomyrmex boliviensis is undoubtedly similar to P. angusticeps in these features.

Distribution based on Regional Taxon Lists
Neotropical Region: Brazil, Colombia, Ecuador, Guatemala, Mexico, Panama, Venezuela.

Nomenclature

 *  petiolatus. Probolomyrmex petiolatus Weber, 1940b: 76, fig. 1 (w.) PANAMA. Agosti, 1995: 433 (q.). See also: Taylor, 1965d: 363; Brown, 1975: 57.

Taxonomic Notes
There is a Brazilian record in the literature for this species (Delabie et al. 2001), but these were described as a new species, Probolomyrmex dentinodis, by Oliveira & Feitosa (2019).

Worker
Taylor (1965) - The unique holotype worker of this species has the following dimensions: HL, 0.51 mm.; HW, 0.36 mm.; SL, 0.29 mm.; CI, 71; SI, 81; WL, 0.65 mm.; PW, 0.27 mm.; dorsal petiole width, 0.14 mm.; petiolar node index, 52; petiole height, 0.27 mm.; petiolar node length, 0.23 mm.; lateral petiolar index, 85. Weber's original description adequately characterises this distinctive species.

Agosti (1994) - HL 0.51-0.64, HW 0.35-0.40, SL 0.31-0.41, TL 0.66-0.88, CI 63-69, SI 70, (2 examined).

Queen
Agosti (1994) - HL 0.61, HW 0.42, SL 0.44, TL 0.90. CI 70, SI 104, (1 examined).