Dolopomyrmex

The only species of the genus is found in desert habitats and in areas that are transitional between desert and mountain foothills.

Identification
Within the Solenopsidini Dolopomyrmex appears to be closer to two exclusively Old World solenopsidine genera, Anillomyrma and Bondroitia. A comparison of the workers is instructive and striking. All three genera share a closely similar structure of the clypeus, frontal lobes, and antennae, strongly oblique mandibular cutting margins with 4 teeth (3 teeth in one Anillomyrma species), and similar petiolar structures, most notably having the spiracle located anterolaterally on the side of the node, reduced palpal counts, and vestigial or absent compound eyes. The only truly discordant note is the absence of a median clypeal seta in Dolopomyrmex, present in Anillomyrma, Bondroitia, and most other Solenopsidine genera. The presence of a median clypeal seta was once thought to be a diagnostic character for the Solenopsidini (Bolton, 1987), but is presently seen to be more variable and less important than previously thought. Bolton’s (2003) recent redefinition of the tribe reflects this change. (Cover and Deyrup 2007)

Nomenclature

 *  DOLOPOMYRMEX [Myrmicinae: Solenopsidini]
 * Dolopomyrmex Cover & Deyrup, 2007: 90. Type-species: Dolopomyrmex pilatus, by original designation.
 * [Dolopomyrmex Fisher & Cover, 2007: 83. Unavailable name.]

Worker
Diagnosis of Worker. Monomorphic subterranean myrmicine ants with the following combination of characters:

1) Palp formula 3,2

2) Mandible with 4 teeth and strongly oblique cutting margin, the largest gap between mandibular teeth separating the basal tooth from the third subapical tooth.

3) Clypeus ecarinate. Median clypeal seta absent, instead anterior margin with pair of long, ventrally curved setae, one on each side of the midpoint, flanked laterally by fringe of 5-6 long, forward-projecting setae on each side of the clypeal margin.

4) Median portion of clypeus narrow, strongly elevated, antennal insertions closely approximated.

5) Frontal lobes small, subtriangular, fully covering condylar bulbs of antennae. Frontal carinae absent.

6) Eyes vestigial or entirely absent, when present, consisting only of the remnant of a single ommatidium.

7) Antennae 11 segmented, with an enormous 3 segmented apical club longer than the remainder of the funiculus.

8) Mesosoma elongate, in profile, compressed laterally at promesonotal juncture with propodeum giving it a distinctive hourglass shape in dorsal view.

9) Metanotal impression present, propodeum lacking teeth or spines, in profile dorsally convex, with flat posterior face in side view.

10) Propodeal spiracle circular, of moderate size. Metapleural gland well-developed. Metapleural lobes small, rounded and inconspicuous.

11) Petiole with short, indistinct peduncle, node low, rounded, suborbicular in dorsal view. Subpetiolar process absent. Spiracle circular, located laterally on the anterior slope of the node.

12) Postpetiole low and rounded in profile, lacking a ventral projection or tooth, suborbicular in dorsal view.

13) Tergite and sternite of the fourth abdominal segment meeting to produce an angulate corner on each side of the postpetiole seen in dorsal view, as in the unrelated myrmicine genus Pheidole.

14) Sting simple, robust.

15) Outer surfaces of middle and hind tibiae and tarsomeres with abundant stiff, spine-like, erect to suberect setae.

Queen
Diagnosis of Queen. As in worker except:

1) Enormous in comparison with worker caste. ML always > TL of largest workers.

2) Mandible with strongly oblique cutting margin and 4 teeth that decrease progressively in size from apical to basal.

3) Submedian ventrally curved setae on anterior clypeal margin not clearly separable from other setae present.

4) Ventral surface of head with abundant, curved, delicate erect setae.

5) Compound eyes large, with scattered very short, stubble-like, erect setae. Ocelli well-developed but small.

6) Antennae 11 segmented as in worker, 3 segmented apical club present, but less pronounced.

7) Body in general somewhat flattened, probably as an adaptation for subterranean life.

8) Mesosoma massive, with full complement of sclerites associated with the presence of wings.

9) Petiolar node subrectangular, wider than long, in dorsal view. Postpetiole subelliptic in dorsal view.

10) Spine-like erect setae abundant on outer surface of hind tibia, especially abundant on the outer tibial surface of the middle leg.

Male
Diagnosis of Male.

1) Palpal formula 2,1. Palps very short.

2) Mandible strap-like, with strongly oblique cutting margin and 4 teeth, decreasing progressively in size from the apex. Rarely, 1-2 teeth may be absent, leaving only the apical and subapical teeth present.

3) As in worker caste, clypeus ecarinate, median clypeal seta absent, paired submedian ventrally curved setae present.

4) Median portion of clypeus narrow, elevated, antennal insertions closely approximated.

5) Frontal lobes small, only partly covering the condylar bulbs, frontal carinae absent.

6) Compound eyes large, with short erect setae as in queen. Ocelli well-developed but small.

7) Antennae 11 segmented, with large 3 segmented club. First antennal segment greatly enlarged to form distinct scape longer than the apical club.

8) Mesosoma massive, alate, wing venation as in Fig. 3. Propodeum lacking teeth or spines, spiracle lenticular, metapleural lobes very small.

9) Petiolar node low and rounded in profile, peduncle absent. Petiolar spiracles located at the tips of large, laterally projecting connules.

10) Postpetiole unique, as in Fig. 3. Attachment to fourth abdominal segment extraordinarily broad, spiracles as in petiole, located at the tips of large, laterally projecting connules.

11) Erect or suberect setae present on outer surfaces of middle and hind tibiae, but neither stiff and spine-like, nor as abundant as in the female castes.