Pseudomyrmex championi

Pseudomyrmex championi
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Pseudomyrmecinae
Genus:	Pseudomyrmex
Species group:	elongatulus
Species:	P. championi
Binomial name
	Pseudomyrmex championi; (Forel, 1899) Specimen Labels
Synonyms
	Pseudomyrma leonhardi Stitz, 1937;

Pseudomyrmex championi occurs in the Sierra Madre Occidental, Sierra Madre del Sur, and the intervening Transmexican Volcanic Belt (Fig. 21). Collection labels with habitat and/or elevation information document the occurrence of this species in oak woodland, oak-pine forest, old field/pasture, mixed tropical/temperate mesic forest, mid-montane dry forest, and yucca desert, at elevations ranging from 1,200 m to 2,344 m (mean 1,828 m; n = 28). Four nests of P. championi encountered by one of us (P.S.Ward) were all from dead twigs of woody shrubs (one Asteraceae, one Verbenaceae, and two unidentified plants). (Ward & Branstetter, 2022)

Identification

Small to medium-sized species (HW 0.82–1.05) with moderately elongate head (CI 0.80–0.87) (Fig. 6) and relatively short eyes (see REL and REL2 values); frontal carinae separated by about basal scape width or less; metanotal groove present but weakly impressed; in profile, dorsal face of propodeum generally flat and more or less differentiated from declivitous face, rounding into the latter, and the two faces subequal in length; petiole moderately slender (PLI 0.49–0.57, PL/HL 0.52–0.56); in profile petiole with slight or no anterior peduncle, the anterodorsal face flat to convex, ascending gradually to summit in posterior half of node, then rounding into more steeply descending posterior face; profemur slender; hind leg relatively short (LHT/HL 0.69–0.75). Head opaque to subopaque, densely punctulate-coriarious, the punctulae on vertex usually separated by less than their diameters (but separated by more than their diameters in some populations, and the vertex correspondingly shinier). Standing pilosity sparse, absent from propodeum and mesonotum (MSC 4–8). Gaster, metacoxa, metafemur and metatibia dark brown, contrasting with light orangebrown mesosoma; head, first and second pairs of legs, petiole, and postpetiole varying from dark brown (usually) to much lighter and concolorous with mesosoma. (Ward & Branstetter, 2022)

The worker of this species is characterized by having a light-colored (orange-brown) mesosoma and contrasting dark gaster and hind leg. The head, other legs, petiole, and postpetiole also tend to be strongly infuscated, but in some samples (from Colima, Jalisco, and Chihuahua) they are lighter colored and even concolorous with the mesosoma. Workers of the closely related Pseudomyrmex apache are uniformly orange-brown in color; see further discussion under that species. Pseudomyrmex championi has been confused with dark brown workers of a more distantly related species, Pseudomyrmex cognatus, which occurs from southern Mexico to Nicaragua. The supposed descriptions of the larva (Wheeler and Bailey 1920, Wheeler and Wheeler 1956) and queen (Kempf 1961) of P. championi actually refer to P. cognatus. Workers of the two taxa can be distinguished as follows: P. championi is conspicuously bicolored, the dark gaster contrasting with the light orange-brown mesosoma, whereas P. cognatus is more uniformly dark brownish-black, with the mesosoma at most moderately lighter (and often dark on top); the metanotal groove is better developed (but still slight) in P. championi compared to P. cognatus; and the eye is generally shorter in P. championi than P. cognatus (REL 0.38–0.44 vs 0.43–0.48). The geographical distributions of P. championi and P. cognatus do not overlap (Figs. 21 and 22) but because they belong to different species complexes in the P. elongatulus group (Fig. 1), they cannot be treated as allopatric variants of the same species. Their similarities must reflect convergence or shared ancestral features. (Ward & Branstetter, 2022)

Keys including this Species

Key to Pseudomyrmex elongatulus group species

Distribution

Latitudinal Distribution Pattern

Latitudinal Range: 28° to 12.99908333°.


North Temperate	North Subtropical	Tropical	South Subtropical	South Temperate

Source: AntMaps; Ward & Branstetter, 2022

Distribution based on Regional Taxon Lists

Neotropical Region: Mexico (type locality).

Distribution based on AntMaps

Distribution based on AntWeb specimens

Check data from AntWeb

Countries Occupied

Number of countries occupied by this species based on AntWiki Regional Taxon Lists. In general, fewer countries occupied indicates a narrower range, while more countries indicates a more widespread species.

Estimated Abundance

Relative abundance based on number of AntMaps records per species (this species within the purple bar). Fewer records (to the left) indicates a less abundant/encountered species while more records (to the right) indicates more abundant/encountered species.

Biology

Castes

Images from AntWeb


Worker. Specimen code casent0246349. Photographer Leah Benuska, uploaded by California Academy of Sciences.	Owned by USNM, Washington, DC, USA.


Syntype of Pseudomyrmex championi. Worker. Specimen code casent0902873. Photographer Z. Lieberman, uploaded by California Academy of Sciences.	Owned by NHMUK, London, UK.


Syntype of Pseudomyrmex championi. Worker. Specimen code casent0907518. Photographer Will Ericson, uploaded by California Academy of Sciences.	Owned by MHNG, Geneva, Switzerland.

Phylogeny

Relationships among Pseudomyrmex elongatulus group species based on Ward & Branstetter (2022).

Pseudomyrmex

Pseudomyrmex salvini

some Pseudomyrmex championi

	some Pseudomyrmex championi

	Pseudomyrmex apache

Pseudomyrmex fasciatus

some Pseudomyrmex cognatus

	some Pseudomyrmex cognatus

	Pseudomyrmex comitator

some Pseudomyrmex arcanus

	some Pseudomyrmex arcanus

	Pseudomyrmex capillatus

Pseudomyrmex veracruzensis

Pseudomyrmex nimbus

Pseudomyrmex exoratus

	Pseudomyrmex ereptor

	Pseudomyrmex elongatulus

Nomenclature

The following information is derived from Barry Bolton's Online Catalogue of the Ants of the World.

championi. Pseudomyrma championi Forel, 1899c: 96 (w.) MEXICO. Wheeler, G.C. & Wheeler, J. 1956: 382 (l.); Kempf, 1961a: 392 (q.). Combination in Pseudomyrmex: Wheeler, G.C. & Wheeler, J. 1956: 382. Senior synonym of leonhardi: Kempf, 1961a: 391.
leonhardi. Pseudomyrma leonhardi Stitz, 1937: 132, figs. (w.) MEXICO. Junior synonym of championi: Kempf, 1961a: 391.

Type Material

Pseudomyrma championi. Syntype worker, Amula, 6000 ft., Guerrero, Mexico (H. H. Smith) (BMNH) [examined by Ward & Branstetter, 2022].
Pseudomyrma leonhardi. Two syntype workers, Guerrero, Mexico (L. Schultze) (ZMHB) [examined by Ward & Branstetter, 2022].

Description

References

Forel, A. 1899f. Formicidae. [part]. Biol. Cent.-Am. Hym. 3: 81-104 (page 96, worker described)
Kempf, W. W. 1961a. Estudos sôbre Pseudomyrmex. III. (Hymenoptera: Formicidae). Stud. Entomol. 4: 369-408 (page 391, Senior synonym of leonhardi)
Kempf, W. W. 1961a. Estudos sôbre Pseudomyrmex. III. (Hymenoptera: Formicidae). Stud. Entomol. 4: 369-408 (page 392, queen described)
Varela-Hernández, F., Medel-Zosayas, B., Martínez-Luque, E.O., Jones, R.W., De la Mora, A. 2020. Biodiversity in central Mexico: Assessment of ants in a convergent region. Southwestern Entomologist 454: 673-686.
Ward, P.S., Branstetter, M.G. 2022. Species paraphyly and social parasitism: Phylogenomics, morphology, and geography clarify the evolution of the Pseudomyrmex elongatulus group (Hymenoptera: Formicidae), a Mesoamerican ant clade. Insect Systematics and Diversity 6(1), 4: 1-31 (doi:10.1093/isd/ixab025).
Wheeler, G. C.; Wheeler, J. 1956. The ant larvae of the subfamily Pseudomyrmecinae (Hymenoptera: Formicidae). Ann. Entomol. Soc. Am. 49: 374-398 (page 382, Combination in Pseudomyrmex)
Wheeler, G. C.; Wheeler, J. 1956. The ant larvae of the subfamily Pseudomyrmecinae (Hymenoptera: Formicidae). Ann. Entomol. Soc. Am. 49: 374-398 (page 382, larva described)

References based on Global Ant Biodiversity Informatics

Castano-Meneses, G., M. Vasquez-Bolanos, J. L. Navarrete-Heredia, G. A. Quiroz-Rocha, and I. Alcala-Martinez. 2015. Avances de Formicidae de Mexico. Universidad Nacional Autonoma de Mexico.
Dattilo W. et al. 2019. MEXICO ANTS: incidence and abundance along the Nearctic-Neotropical interface. Ecology https://doi.org/10.1002/ecy.2944
Fernández, F. and S. Sendoya. 2004. Lista de las hormigas neotropicales. Biota Colombiana Volume 5, Number 1.
Field Museum Collection, Chicago, Illinois (C. Moreau)
Kempf W. W. 1961. Estudos sôbre Pseudomyrmex. III. (Hymenoptera: Formicidae). Studia Entomologica 4: 369-408.
Kempf, W.W. 1972. Catalago abreviado das formigas da regiao Neotropical (Hym. Formicidae) Studia Entomologica 15(1-4).
Longino J. T. 2013. Ants of Nicargua. Consulted on 18 Jan 2013. https://sites.google.com/site/longinollama/reports/ants-of-nicaragua
Lopez, A. S., M. Vasquez-Bolanos, and G. A. Q. Rocha. 2015. Hormigas (Hymenoptera: Formicidae) del Cerro de la Culebra, Arandas, Jalisco, Mexico. Dugesiana 19: 151-155.
Vásquez-Bolaños M. 2011. Lista de especies de hormigas (Hymenoptera: Formicidae) para México. Dugesiana 18: 95-133
Wheeler, William Morton. 1916. Ants Collected in Trinidad by Professor Roland Thaxter, Mr. F. W. Urich, and Others. Bulletin of the Museum of Comparitive Zoology at Harvard University. 40(8):322-330