Temnothorax whitfordi

Mackay (2000) "This species nests in branches of Quercus oaks (gray oak, Arizona oak) and other trees, including a mesquite branch (Prosopis glandulosa), which was full of tunnels, at a height of 3 meters (San Luis Potosi). The habitat ranges from desert scrub, with Yucca sp., Prosopis sp., and Opuntia spp. to oak forests. Brood were found in nests in August. One completely excavated nest contained 1 queen, 2 males and 35 workers (# 10956), a second contained 1 queen and 116 workers (# 17975). A single worker was collected loose in an unspecified tree, in a desert arroyo with oaks and Celtis. Specimens in the Davis Mts. were collected in mixed pine-juniper-oak forests. Nests in the Guadalupe Mts. were found in mixed oak-pinyon pine-juniper forests. The soil is a rocky loam, or rocky fine sand. When the nests are disturbed, they primarily attempt to rescue the brood. They are also much more aggressive than the typical Leptothorax, attacking and stinging. The sting is surprisingly painful, similar to that of the thief ants in the genera Solenopsis or Wasmannia. Liometopum apiculatum also nests in branches of the oaks, and this Leptothorax may be so aggressive as it must protect nests from the former species, which were attempting to prey on the brood of Leptothorax during excavation."

Identification
Mackay (2000) "The workers of this species are small, dark brown specimens with an 11-segmented antenna. The dorsum of the head is mostly smooth and shining, the pronotum is almost completely covered with coarse punctures. The dorsum of the head and pronotum may be smooth and shining. The propodeal spines consist of tiny angles. The petiole is thickened with a round node.

The presence of an 11-segmented antenna easily separates Temnothorax whitfordi from all of the other species in the subgenus with similar sculpture. The smooth dorsum of the head and partially smooth pronotum would separate it from Temnothorax schaumii. The sculpture of the mesosoma is nearly identical to that of Temnothorax mexicanus. The specimen from near Las Cruces differs from the type series in that the propodeal spines are more developed, the subpeduncular process is poorly developed (well developed in the type series) and the pronotum is covered with larger punctures that approach the form of foveolae (punctures in "normal" Temnothorax whitfordi, with a few wavy striae and areas that are nearly smooth and shining). Specimens from the Davis Mountains are similar in having more developed spines (they are still small), nearly foveolate punctures on the pronotum, but have a well developed subpeduncular process. Some of the specimens from Mexico (San Luis Potosi) differ from the New Mexican specimens. The pronotum of these specimens is partially smooth and shining, whereas the entire mesosoma of Temnothorax whitfordi is usually heavily punctate, nearly foveolate (Fig 189). The top of the dorsal face of the propodeum of this form has fine transverse rugulae, the similar surface of Temnothorax whitfordi is punctate (sides of the propodeum may have poorly defined longitudinal striae). There is a transition between the sculpturing of all of these various extremes, and they are thus considered to be Temnothorax whitfordi. It is possible that Temnothorax whitfordi is a species complex, but further collecting will be necessary to evaluate the variability within the species."

Distribution
USA, MEXICO. US: Arizona, Southeastern New Mexico, western Texas. Mexico: northern Mexico.

Habitat
Desert scrub to oak forests.

Abundance
Only known from a few collections.

Worker
Mandibles with 5 or 6 teeth; anterior border of clypeus concave to convex, clypeus with well defined medial carina, 2 or 3 lateral carinae; sides of head and vertex straight or weakly concave; scape short, extendingabout 3/4distance to posterior corner of head, antenna with 11 segments; mesosoma with none of sutures breaking surface sculpture; propodeal spines consisting of tiny angular processes; peduncle of petiole with well developed ventral tooth, with prominent flange above point of attachment, anterior petiolar face straight, posterior face convex, petiolar node broadly rounded and blunt.

Hairs scattered and erect, with blunt or weakly spatulate tips, present on most surfaces, except legs and antennae, especially coarse and blunt tipped on petiole and postpetiole; decumbent pubescence sparse, present on legs and antennae.

Sculpture characteristic of this species: head in large part smooth and shining, lateral parts with fine costulae, fine rugae between eye and frontal carinae and eye and base of mandibles, entire mesosoma, petiole and postpetiole completely covered with coarse, dense punctures, but shining, pronotum may be lightly punctate, but gaster smooth and polished.

Color: medium to dark brown.

Worker measurements: HL 0.54-0.62, HW 0.47-0.55, SL 0.370.41, EL 0.15-0.18, WL 0.62-0.71, PW 0.14-0.18, PL 0.16-0.22, PPW 0.18-0.22, PPL 0.14-0.17. Indices: CI 87-93, SI 66-69, PI 70-100, PPI 113-157.

Queen
Similar to worker in most aspects, differing in that rugae extend over entire surface of head, intrarugal spaces shining, sides of mesosoma shining, but with abundant striae and rugae, propodeal spines consisting of only angles, apex of node of petiole more angulate.

Female (dealate) measurements: HL 0.65, HW 0.64, SL 0.44, EL 0.20, WL 1.15, PPW 0.31, PPL 0.19. Indices: CI 98, SI 68, PPI 163.

Male
Mandible with 3 or 4 teeth; median anterior border of clypeus convex, clypeus with longitudinal carinae. without any transverse carinae; eyes large; ocelli well developed; scape very short, about as long as first 3 funicular segments; propodeum rounded posteriorly, without evidence of angles; petiole with low, rounded node, ventral surface of peduncle without tooth or flange.

Erect hairs very sparse on body, some, with pointed tips, especially on gaster; decumbent pubescence absent.

Sculpture mostly smooth and shining, dorsum of head lightly punctate with rugae on sides of head.

Color: light brown.

Male measurements: HL 0.42-0.43, HW 0.46-0.47. SL 0.08-0.10. EL 0.22-0.23, WL 0.86-0.91. PW 0.14-0.17, PL 0.13-0.16. PPW 0.17, PPL 0.14-0.16. Indices: CI 107-112, SI 19-24, PI 88-131. PPI 106-121.

Type Material
As reported in Mackay (2000) "Holotype worker (MCZC) and 63 paratype workers (AMNH, CASC, CWEM, FMNH, LACM, EMAU, MCSN, MCZC, MHNG, MZSP, USNM, UNAM)."

Type Locality Information
USA, New Mexico, Eddy Co., Guadalupe Mountains, 5.3 k SE Sitting Bull Falls, 32°12'15"N 104°40'23"W, 1559 meters, 31-viii-1997, W&E Mackay # 17575, 17566.

Etymology
Patronym. "Named in honor of my close friend, Dr. Walter Whitford, who has published many papers on the ants of southwestern United States."

Additional References

 * MacKay, W. P. 2000. A review of the New World ants of the subgenus Myrafant, (Genus Leptothorax) (Hymenoptera: Formicidae). Sociobiology. 36:265-444.