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Species: Pheidole risii   Forel, 1892 

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Taxonomic History (provided by Barry Bolton, 2023)

Pheidole risii Forel, 1892a PDF: 38 (s.w.q.m.) ARGENTINA (Buenos Aires). Neotropic. Primary type information: Primary type material: syntype major workers, syntype minor workers, syntype queens, syntype males (numbers not stated). Primary type locality: Argentina: vic. Buenos Aires, 1.i.1891 (Fr. Ris). Primary type depositories: MCZC, MHNG. AntCat AntWiki HOL

Taxonomic history

// Distribution


  Geographic regions (According to curated Geolocale/Taxon lists):
    Americas: Argentina, Brazil
  Biogeographic regions (According to curated Bioregion/Taxon lists):

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 risiiHNS Forel

Pheidole risiiHNS Forel 1892a: 38. Raised to species level in this monograph: rugatulaHNS, trachydermaHNS.

Types Mus. Hist. Nat. Geneve; Mus. Comp. Zool. Harvard.

Etymology Named after the collector, Fr. Ris.

diagnosis Similar in various traits to aperHNS, bambusarumHNS, breviconaHNS, dyctiotaHNS, laeviventrisHNS, lutziHNS, rugatulaHNS, senilisHNS, sigillataHNS, trachydermaHNS, and trainiHNS, differing as follows.

Major: shallow antennal scrobes; pilosity along dorsal profile of head dense, with uniform short hairs about as long as Eye Length along the posterior half and much longer hairs along the anterior half; occipital cleft deep; occipital lobes smooth and subangulate; pronotum sparsely carinulate, mostly smooth; propodeal spine very stout, equilaterally triangular; postpetiolar node very broad, 2X broader than petiolar node, and spinose.

Minor: occiput, humeri, and propodeal dorsum rugoreticulate; almost all of head and mesosoma foveolate; occiput broad, concave, and lacking nuchal collar.

Measurements (mm) Syntype major: HW 0.96, HL 1.02, SL 0.44, EL 0.12, PW 0.54. Syntype minor: HW 0.66, HL 0.66, SL 0.62, EL 0.12, PW 0.44. color Major: body reddish yellow except for gaster, which is yellowish brown. Minor: concolorous dark yellow.

Range In addition to the type locality, risiiHNS has been recorded from Sao Paulo, Brazil (Kempf 1972b).

Biology Unknown.

Figure Upper: syntype, major. Lower: syntype, minor. ARGENTINA: Buenos Aires (Fr. Ris). Scale bars = 1 mm.

Specimen Habitat Summary

Collect Date Range: collected on 2011-01-01 00:00:00.0

Type specimens: syntype of Pheidole risii: casent0908198, casent0908199, casent0917783, casent0922215; type of Pheidole risii: focol0623-1, focol0623-2

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