Pheidole species groups of Madagascar

Species group Identification
Key to Pheidole species groups of Madagascar

Pheidole annemariae species group

 * Pheidole annemariae species group

There are two species in this group. See the species group page for their identification.

Major workers of this group can be distinguished based on a combination of the following characters: head in full-face view rectangular, and in lateral view sub-rectangular; scrobe surface foveolate to rugo-foveolate, with distinct and thin longitudinal rugae; posterior mesonotum with distinct teeth-like projections, and long, triangular propodeal spines. Minor workers can be separated based on foveolate head and mesosoma, with at least partly smooth genae, katepisternum, and mesonotum; presence of mesonotal spines and long propodeal spines.

Pheidole bessonii species group
This group of Indoastralian species needs to be revised.

Pheidole curvistriata species group

 * Pheidole curvistriata species group
 * Key to Pheidole curvistriata species group

Major workers of this group can be distinguished based on a combination of the following characters: head in full face view rectangular, slightly widening posteriorly, in lateral view sub-rectangular; occipital lobes with thick, sparse, irregular rugae, interspaces smooth to finely rugulose; moderately long and narrow propodeal spines; finely rugoreticulate or foveolate mesosoma with smooth katepisternum and at least lower part of anepisternum; finely shagreened first gastral tergite, and brown to dark brown body. Minor workers can be easily distinguished based on foveolate head with additional rugae on frons and irregular to arcuate rugae on vertex; foveolate mesosoma usually with additional irregular rugae and yellow to brown body.

Pheidole diakritos species group

 * Pheidole diakritos species group

There is a single species in this group; see the species group page for more details.

This species-group can be easily distinguished from others by presence of deep antennal sockets and distinct lobe-like frontal lobes in both, major and minor workers. Major workers also can be distinguished by absence of outer hypostomal teeth, and minor workers by presence of short triangular tubercles on the humeral area.

Pheidole ensifera species group

 * Pheidole ensifera species group
 * Key to Pheidole ensifera species group

Species of this group are characterized by a large body size, both in minor and major workers. Major workers can be distinguished from others based on a combination of the following characters: head in full-face view rectangular, in lateral view elongate and oval; antennal scrobes with fine, longitudinal to irregular rugulae; occipital lobes and genae smooth or with sparse rugoreticulation; inner and outer teeth closely spaced and connected by concavity, and long to very long propodeal spines. Minor workers can be distinguished based on smooth to rugo-punctuate surface of frons; relatively short scape (surpassing posterior head margin by one- to two-fifths of its length); high, short, and convex promesonotum; very to moderately long propodeal spines, and bright brown to dark brown body colouration.

Pheidole ferruginea species group

 * Pheidole ferruginea species group
 * Key to Pheidole ferruginea species group

Major workers of this group can be distinguished based on the combination of following characters: cordate to sub-oval head in lateral view, oval to sub-oval in dorsal view; well-developed antennal scrobes delimited by carinulae (except P. longipilosa); never smooth occipital lobes; lack of promesonotal and metanotal grooves; moderately long to long propodeal spines; strong sculpture of mesosoma, occasionally with smooth notches and bright brown to brown body. Minor workers can be separated entirely foveolate head, sometimes with additional longitudinal rugae on frons; short scape surpassing posterior head margin by one- to two-fifths of its length; and moderately long or very long propodeal spines (except P. longipilosa).

Pheidole fervens species group

 * Pheidole fervins species group

Pheidole longispinosa species group

 * Pheidole longispinosa species group
 * Key to Pheidole longispinosa species group

Pheidole lucida species group
An Indoaustralian group that is in need of revision.

Pheidole lutea species group

 * Pheidole lutea species group
 * Key to Pheidole lutea species group

Major workers of this group can be easily distinguished from others based on elongate to oval head capsule in full-face view and sub-oval in lateral view, head sculpture weakening posteriorly and reduced sculpture of mesosoma, strongly reduced and sometimes absent to small propodeal spines, and bright body colouration. Minor workers can be separated from other species based on smooth and shiny head and mesosoma sculpture, short scape, and yellow body colouration.

Pheidole makaensis species group

 * Pheidole makaensis species group
 * Key to Pheidole makaensis species group

Major workers can be distinguished based on a combination of the following characters: head in full-face view elongated; sides of the head with moderately dense, long to very long, erect pilosity; occipital lobes always with arcuate and/ or transverse rugae; genae at least with a smooth notch; inner and outer teeth closely spaced and connected by concavity. Minor workers can be distinguished based on foveolate head and mesosoma, with genae at least with a smooth notch; small, triangular propodeal spines; yellow to dark yellow body colouration.

Pheidole masoala species group

 * Pheidole masoala species group
 * Key to Pheidole masoala species group

Species of this group have small body size, in both major and minor workers. Major workers can be distinguished by a combination of the following characters: head in full-face and lateral views sub-rectangular or oval with flat ventral and dorsal faces; in most cases antennal scrobes, when present, are indistinctly to distinctly delimited; foveolate sculpture on the lateral sides of head, sometimes with additional rugae (except P. lamperos); frons always with longitudinal rugae and occipital lobes with irregular rugae; relatively low and evenly angular promesonotum; lack of promesonotal groove, and never entirely smooth mesosoma. Minor workers can be distinguished based on at least partly foveolate head and mesosoma, with smooth genae; short scape reaching the posterior head margin or surpassing it by at most two-fifths of its length; low, long, flat, or slightly convex promesonotum, with relatively convex to steep posterior declivity; and lack of promesonotal groove.

Pheidole megacephala species group
An Afrotropical and Malagasy species group that is in need of revision (see Afrotropical Pheidole species groups). A few species in this group have been spread to other parts of the world.

Pheidole nemoralis species group

 * Pheidole nemoralis species group
 * Key to Pheidole nemoralis species group

Major workers of this group can be distinguished based on the combination of the following characters: relatively small body size; square or subrectangular head in full-face view, indistinct and not delimited by carinulae antennal scrobes with scrobe surface foveolate with sparse, thick, longitudinal to irregular rugae; occipital lobes with indistinct to distinct, sparse, irregular rugae with smooth to foveolate interspaces; frons with dense, thick, and longitudinal rugae, moderately short and relatively low promesonotum, lack of promesonotal and metanotal grooves, entirely sculptured mesosoma and bright brown to dark brown body.

Pheidole petax species group

 * Pheidole petax species group
 * Key to Pheidole petax species group

Major workers of this group can be separated by the combination of the following characters: rectangular or square head in full-face view (except P. boribora) in lateral view sub-rectangular, shallowly impressed antennal scrobes usually not delimited by carinulae (except P. ankerana complex), thick, sparse, irregular rugae on occipital lobes and frons always with thick longitudinal rugae; foveolate antennal scrobes (except P. glabra sp. nov. and P. ankerana complex); relatively low and angular promesonotum and yellowish brown to black body. Minor workers can be separated based on foveolate head, sometimes with few additional rugae and smooth notches on genae and frons, short scape which, when laid back, surpass the posterior head margin by one- to two-fifths of its length, foveolate mesosoma, sometimes with smooth notches on the lateral sides and yellow to yellowish brown body (except P. brevipilosa complex).

Pheidole sikorae species group

 * Pheidole sikorae species group
 * Key to Pheidole sikorae species group

Species of the P. sikorae group, especially major workers, are most similar to some representatives of the P. lutea group (Pheidole ranohirensis, Pheidole lutea, and Pheidole voasara) and members of the P. ferruginea'' group.

Majors of the sikorae group can be easily distinguished from those of the P. ferruginea group based on absence of antennal scrobes, lower promesonotum in lateral view, shorter and thicker propodeal spines and smooth to indistinctly shagreened first gastral tergite; from members of the P. lutea group they differ in lack of antennal scrobes, longer scape which exceeds midlength of the head, and thicker head sculpture, especially on its posterior part. Minor workers can be more confusing and species determinations should be always made based on nest samples consisting of major and minor workers. Overall, minors of the sikorae group can be distinguished from others based on the combination of the following characters: body yellow to black; promesonotum, in lateral view, from short and arched to long and low but never box-like and never with steep posterior mesonotum; propodeal spines most often minute to small, never long and sharp; head in full-face view sub-rectangular to sub-oval but never elongated.

Additional Resources

 * Pheidole
 * Madagascar
 * Pheidole species groups