Pogonomyrmex apache

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Pogonomyrmex apache
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Pogonomyrmecini
Genus: Pogonomyrmex
Species group: barbatus
Species: P. apache
Binomial name
Pogonomyrmex apache
Wheeler, W.M., 1902

Pogonomyrmex apache casent0006284 profile 1.jpg

Pogonomyrmex apache casent0006284 dorsal 1.jpg

Specimen Label

Synonyms

Typically constructs cryptic nests in stony soils, they are small and difficult to locate. Nest entrances may be a plain hole or with a small (10 cm diameter) mound of soil. Colonies are small, from perhaps eighty to a few hundred workers. A founding female was collected in July. Although they are large individuals, they are not as aggressive as others in the genus.

Identification

Pogonomyrmex apache is readily distinguishable in all castes from its closest relatives. The excised clypeus is distinctive, as is the very short declivity of the propodeum of the worker. Within its complex, only apache has the propodeal declivity so short in the worker and transversely rugose in the worker and female; in other species the declivity is smooth and strongly shining. From all known North American species of Pogonomyrmex, the male of apache differs materially by its distinctive paramere and, except from that of bicolor, by its strongly shining, concolorous black body.

Keys including this Species

Distribution

United States: western Texas, southwestern Colorado, southwestern New Mexico, southern Arizona, southern Nevada. Mexico: Sonora, Chihuahua, and Durango.

Distribution based on Regional Taxon Lists

Nearctic Region: United States (type locality).
Neotropical Region: Mexico.
Pogonomyrmex apache Distribution.png

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Distribution based on specimens

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The above specimen data are provided by AntWeb. Please see Pogonomyrmex apache for further details

Habitat

Creosotebush scrub, desert grasslands, sagebrush.

Biology

Cole (1968) - Although Pogonomyrmex apache generally constructs obscure nests in stony soils with no superstructure to mark a colony, sometimes it builds circular craters in very sandy soil. A few nests of the latter type were found by the writer at the station near Road Fork, New Mexico. Colonies are generally small and only contain upward of about eighty workers. The inoffensive workers forage at an erratic, hesitating gait which is wholly unlike that of other members of its complex. The movements are somewhat similar to those of Pogonomyrmex maricopa. For a more detailed account of the habits of apache the reader is referred to a previously published description (Cole 1954b pp. 268-9).

Since my earlier paper on apache, I have made numerous additional collections of this species in Texas, Arizona, and New Mexico. Nests are common near Ozona, Sheffield, and Ft. Stockton, Texas. I found a single stray worker near Lake Mead, Nevada, and two nests at a station fifty-four miles north of Hermosillo, Sonora, Mexico. Gregg (1963. p. 319) has published an interesting record of apache from Canyon City, Fremont County, Colorado, at an elevation of 5,333 feet. This is the most northern station known for the species. The nest was found in a meadow within a pinyon-cedar area. There is also a record from Morton County, Kansas, at an elevation of 3,200 feet, but inasmuch as I have been unable to locate either the specimens involved or the exact source of the record, the authenticity must remain questionable.

Castes

Nomenclature

The following information is derived from Barry Bolton's New General Catalogue, a catalogue of the world's ants.

  • apache. Pogonomyrmex apache Wheeler, W.M. 1902c: 392 (w.) U.S.A. Cole, 1954e: 269 (q.m.); Taber, Cokendolpher & Francke, 1988: 51 (k.). Senior synonym of sanctihyacinthi: Cole, 1954e: 267. See also: Cole, 1968: 49.
  • sanctihyacinthi. Pogonomyrmex sanctihyacinthi Wheeler, W.M. 1902c: 388 (w.) U.S.A. Junior synonym of apache: Cole, 1954e: 267.

Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.

Cole (1968) - Additional studies of apache have confirmed my previous conclusion (Cole, 1954b, p. 267) that the populations which were named apache Wheeler and sancti-hyacinthi Wheeler are conspecific. As a matter of fact, on Fisher Hill, Ft. Davis Mountains Texas I found colonies answering to both descriptions. Pogonomyrmex apache is a highly variable ant in the worker caste, and it is easy to see how Wheeler (1902a, pp. 388, 392) could have described it under two names, especially since relatively few specimens had been collected at that time.

Description

Worker

(Cole 1968) - HL 1.63-2.17 mm, HW 1.79-2.28 mm, CI 105.1-111.7, SL 1.33-1.60 mm, SI 68.4-74.3, EL 0.38-0.42 mm, EW 0.23-0.30 mm, OI 19.4-25.8, WL 1.90-2.51 mm, PNL 0.38-0.49 mm, PNW 0.34-0.42 mm, PPL 0.46-0.53 mm, PPW 0.57-0.72 mm.

Mandible with apical, subapical, and all basal teeth except ultimate short, broad, blunt; apical and subapical teeth frequently fused except terminally; length of first, second, third, and penultimate basal teeth subequal; ultimate basal tooth narrower and somewhat shorter than other basals, not offset from the straight basal mandibular margin.

Base of antennal scape similar to that of Pogonomyrmex barbatus, but bend of shaft a little more constricted and somewhat flattened; longitudinal peripheral carina very strong, its proximal portion greatly elevated and extending to the basal flange, that pan of the carina bordering the lateral impression of inferior lobe very high and forming, together with incorporated portion of basal flange, a very prominent, deep, subtriangular trough that slopes toward the unflanged inner margin of the basal enlargement; point absent; apex of superior lobe rather blunt.

Medio-anterior portion of frontal lobe of head strongly elevated from adjoining peripheral part of median lobe of clypeus, the two forming nearly a right angle and producing a deep impression for the median clypeal lobe and adjacent frontal area, the frontal area being a pit with steep sides; lateral clypeal lobes very narrow and angularly produced anteriorly in the form of a prominence with sharply rounded apex; anterior margin of median clypeal lobe moderately to strongly excised, the impression being from broad and shallow to narrow and very deep, often extending nearly to level of frontal lobes.

Cephalic rugae dense, closely spaced, very delicate, irregular, frequently broken, fading out on occipital corners which are moderately to strongly smooth and shining. Interrugal spaces generally with very delicate punctures. moderately to strongly shining.

Contour, in lateral view, of thorax. petiole, and postpetiole as portrayed in Pl. V, Fig. 2; thoracic dorsum very broadly and weakly convex; epinotum unarmed or with a pair of tubercles, angles, denticles, or very short spines; epinotal declivity extremely short; anterior declivity of peliolar node rather short, meeting the peduncle at a broad and usually weak, well-rounded angle; dorsum of petiolar node very weakly convex or naltened, the apex rather blunt; petiolar peduncle much higher posteriorly than anteriorly, with a prominent, lobular, ventral process of variable development; ventral process of postpetiole not strongly developed. Thoracic rugae dense, closely spaced, moderately to very delicate, longitudinal or transverse on pronotum, transverse elsewhere; interrugal spaces with or without delicate punctures, moderately to strongly shining. Contours of petiolar and postpetiolar nodes, in dorsal view, as shown in Pl. VII. Fig. 19. Petiolar node, viewed from above, with unevenly spaced, broken, transverse rugulae and striae; interrugal spaces faintly punctate and somewhat shining to finely striatopunctate and strongly shining. Postpetiolar node, viewed from above, densely, finely punctate, with a few transverse rugulae and striae confined largely to posterior surface and weakly shining, or only very densely, finely, and evenly punctate and moderately shining. Gaster densely, rather strongly, and prominently shagreened and rather strongly shining.

Body color varying from a rather uniform bright orange to a concolorous, medium to deep, ferrugineous red.

Queen

Cole (1968) - HL 1.86-1.90 mm, HW 2.09-2.13 mm, CI 110.0-114.3, SL 1.42-1.44 mm, SI 67.6-67.9, EL 0.47-0•49 mm, EW 0.28--0.34 mm, OI 24.0-26.5, WL 2.77-2.81 mm, PNL 0.42-0.47 mm, PNW 0.49-0.53 mm, PPL 0.49-0.53 mm, PPW 0.76-0.80 mm.

Cephalic features similar to those of the worker. Thoracic rugae denser and coarser than those of the worker; longitudinal except on collar and anterior declivity of pronotum and on epinotal base and declivity where they are transverse; more widely spaced on epinotum than elsewhere; sparse or absent from the nearly smooth and shining scutellum where they are often replaced by sparse, faint, uneven, broken striae. Epinotum without armature or with a pair of minute denticles. Interrugal sculpture of thorax similar to that of the worker. Venter of petiolar peduncle with a prominent blunt process. Dorsum of peliolar node, in lateral view, flattened or only faintly convex, the apex rather acute. Postpetiolar ventral process only moderately well developed. Sculpture of petiolar and postpetiolar nodes similar to that of the worker, but the surface generally shagreened, smoother and more highly polished. Gaster shining, very finely shagreened. Body color a ferrugineous red; the first gastric segment usually with a posterior, uneven, infuscated, transverse band, other segments generally with narrower and fainter such bands.

Male

Cole (1968) - (adapted from Cole, 1954b, pp 269-70). HL 1.52-1.68 mm, HW 1.76-1.82 mm, CI 114.3-115.1, SL 0.68-0.87 mm, SI 39.1-54.8, EL 0.49-0.53 mm, EW 0.28-0.34 mm, OI 32.2-33.3, WL 2.70-2.85 mm, PNL 0.49-0.53 mm, PNW 0.76-0.80 mm, PPL 0.49-0.57 mm, PPW 0.91-0.99 mm.

Mandible as shown in Pl. VIII, Fig. 12; similar to that of barbatus, but blade notably narrower, its apical margin straighter, basal angle weaker, apical tooth broader and blunter, and basal teeth more weakly developed, usually with only the first one discernible. Length of antennal scape approximately equal to, or a little longer than combined lengths of first and second flagellar segments; apical segment of flagellum about twice the length of penultimate segment which is distinctly longer than broad. Anterior margin of median clypeal lobe rather deeply and broadly excised.

Upper surface of head with fine, irregular, longitudinal, undulating, non-reticulate rugae, becoming more widely spaced and fewer posteriorly. Rugae above frontal area and between it and median ocellus forming two lateral oblique series with their upper ends nearly meeting in the area below the median ocellus. Interrugal sculpture consisting of elongate, foveate, piligerous punctures. Posterior corners of head without rugae but with coarse, elongate, foveate, piligerous punctures and fine, epiligerous punctures. Sides of head with coarse, piligerous punctures and very fine undulating rugules which tend to form faint reticulations behind the compound eyes. Lateral lobes of clypeus with a few coarse, longitudinal rugae; anterior portion of median lobe of clypeus coarsely and reticulately rugose, the posterior portion with a few short, longitudinal rugae. Frontal area virtually smooth except for the median carinula and a few, fine, longitudinal rugules. Interrugal areas, except those on anterior portion of median clypeal lobe and the lateral lobes, shining. Mandibles coarsely and longitudinally rugose. Interrugal areas of mandibles and of anteriomedial portion of clypeus and its lateral lobes subopaque. All interrugal areas with piligerous punctures. Venter of the head with scattered fine punctures.

Entire thorax shining; the scutum, scutellum, and basal face of epinotum very shining. Dorsoventral margins of pronotum with coarse irregular rugae. Mesothoracic sternites with fine, longitudinal rugae. Posteriodorsal portion of scutum with curved, irregular, fine to rather coarse, longitudinal rugae. Dorsomesal portion of scutellum with a few, short, irregular, longitudinal rugules. Metanotum with very coarse, longitudinal rugae. Sides of epinotum and mesothorax with a few, curved, fine rugae interspersed with fine, scattered punctures. A few, fine, oblique rugae near apex of declivous face of epinotum. Entire thorax with rather sparse, fine, scattered, epiligerous punctures and somewhat more numerous, large, piligerous punctures. Antennal flagella subopaque to opaque, with piligerous punctures; scape with elongate, foveaceous, piligerous punctures.

Petiole in profile with a short anterior peduncle, the ventral tooth of which is blunt and poorly developed; the node with convex sides, anterior and posterior surfaces, and apex; viewed from above the node is subglobular and somewhat narrower than the postpetiole which, when viewed from above, is subtrapezoidal. Upper surface of petiolar node rather smooth and shining, with a few, fine punctures and numerous, coarser, piligerous ones. Posteriodorsal and posteriolateral margins of petiole dull and finely granulose. Postpetiole smooth and very shining, with a few, scattered, fine punctures and more numerous, coarser, piligerous punctures.

Erect hairs long, numerous, rather uniformly distributed, curved, attenuated, and light yellowish gray; sparser on dorsum of scutum and scutellum; absent, or nearly so, from entire median portion of declivous face of epinotum; somewhat shorter on posterior half of gaster and occurring chiefly along posterior border of each segment. Hairs erect and suberect on antennal scapes and first four funicular segments, usually fully appressed on remaining segments and with only an occasional hair suberect.

Paramere as shown in PL. X, Fig. 12 and Pl. XI, Fig. 13; terminal lobe deeply and broadly excised on inner surface, the strong concavity fringed with a wide band of long, dense, reflexed, rather fine, still, golden hairs; outer margin of terminal lobe with scattered, rather widely spaced, short, straight, erect, delicate, golden hairs arising from large punctures; inner margin of terminal lobe with a prominent lobe and anterior to it a smaller, spinelike, process, the margin between the two deeply and broadly concave; distal margin of paramere truncate and crenulate.

Body chiefly a concolorous, shining black; legs, terminal gastric segments, and parameres brown; dorsum of first gastric segment sometimes with brown splotches.

Syntype Specimen Labels

Type Material

Cole (1968) - Type locality: Ft. Davis, Texas. American Museum of Natural History, Museum of Comparative Zoology, Creighton Coll.

References