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Species: Pheidole scalaris   Wilson, 2003 

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Note: Not a Valid Taxon Name

Current Valid Name:

Pheidole transversostriata

Taxonomic History (provided by Barry Bolton, 2019)

Pheidole scalaris Wilson, 2003A: 643, figs. (s.w.) COSTA RICA. Neotropic. AntCat AntWiki HOL

Taxonomic history


  Geographic regions: Not found on any curated Geolocale/Taxon lists.

Distribution Notes:

Costa Rica (Atlantic and northern Pacific lowlands).


Natural History:

Occurs in both seasonal dry forest and lowland rainforest; recruits to baits; does not occur in Winkler samples, which implies that it neither nests nor forages in forest leaf litter.

Taxonomic Treatment (provided by Plazi)

Treatment Citation: Wilson, E. O., 2003, Pheidole in the New World. A dominant, hyperdiverse ant genus., Cambridge, MA: Harvard University Press

Pheidole scalarisHNS new species

Types Mus. Comp. Zool. Harvard.

Etymology L scalarisHNS, of a ladder, alluding to the strong ladder-like pattern on the dorsum of the major head. diagnosis Close to transversostriataHNS but distinguished from it and other members of the transversostriataHNS group by the broad occipital zone of rugoreticulum on the dorsal surface of the head of the major, surmounting a wide "ladder" of parallel transverse carinulae that reach the frontal lobes, where they curve anteriorly to the ends of the lobes; also, the premesonotal dorsum is completely covered by transverse carinulae. Also, see the distinctive color of the minor (below).

This species is possibly synonymous with P. transversostriata var. nigridensHNS Forel of Colombia, which has been provisionally synonymized with transversostriataHNS; nigridensHNS has rugoreticula on the occipital corners and more carinulae on the pronotal dorsum, and is intermediate between scalarisHNS and transversostriataHNS. However, scalarisHNS also differs from transversostriataHNS by the more elongate head of the major (Head Length 1.3X Head Width versus 1.2X in transversostriataHNS) and smooth sides of the pronotum of the minor. Measurements (mm) Holotype major: HW 0.64, HL 0.84, SL 0.32, EL 0.10, PW 0.36. Paratype minor: HW 0.42, HL 0.46, SL 0.36, EL 0.08, PW 0.26. Color Major: concolorous medium yellow.

Minor: overall light brownish yellow, with medium brown vertex, occiput, and dorsum of promesonotum, and medium yellow appendages.

Range Atlantic and northern Pacific lowlands of Costa Rica; and Arima Valley, Trinidad.

Biology Longino (1997) found P. scalarisHNS in both seasonal dry forest and evergreen forest. The workers were recruited to baits on the forest floor.

Figure Upper: holotype, major. Lower: paratype, minor. COSTA RICA: La Selva Biological Station, near Puerto Viejo, Heredia (Stefan Cover). Scale bars = 1 mm.

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