Veromessor stoddardi

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Messor stoddardi
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Stenammini
Genus: Veromessor
Species: V. stoddardi
Binomial name
Veromessor stoddardi
(Emery, 1895)

Messor stoddardi casent0005735 profile 1.jpg

Messor stoddardi casent0005735 dorsal 1.jpg

Specimen labels

Apparently rare or very local in its distribution. The senior author has taken one worker at Jacumba, California, on the border of Mexico, but with the exception of this specimen the species appears to be known only from type material. Nothing is known of the habits of stoddardi. The lack of ammochaetae might indicate incomplete xerophilous adaptation. (Wheeler and Creighton 1934)

Identification

Because of its unusually short epinotal spines, stoddardi is not likely to be confused with any of the other species in the genus, with the possible exception of Veromessor pergandei. In the case of the latter species, however, there are so many other differences that confusion is extremely unlikely. The dark color, elongate eyes, well-developed ammochaetae, and smooth integument of pergandei all serve to distinguish it from stoddardi. In the smaller workers the head is slightly longer than broad and the antennal scapes extend almost to the occipital border. In other respects they conform to the description. (Wheeler and Creighton 1934)

Identification Keys including this Taxon

Key to Veromessor species

Distribution

Distribution based on Regional Taxon Lists

Nearctic Region: United States (type locality).
Neotropical Region: Mexico.
Veromessor stoddardi Distribution.png

Distribution based on specimens

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The above specimen data are provided by AntWeb. Please see Veromessor stoddardi for further details

Biology

Castes

Nomenclature

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

  • stoddardi. Stenamma (Messor) stoddardi Emery, 1895c: 307 (w.) U.S.A. Combination in Novomessor: Emery, 1915d: 73; in N. (Veromessor): Forel, 1917: 235; in Veromessor: Wheeler, W.M. & Creighton, 1934: 385; in Messor: Bolton, 1982: 341; in Veromessor: Ward et al., 2014: 13.

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

Description

Worker

Wheeler and Creighton (1934) – Length 4-6 mm.

Head exclusive of the mandibles as broad as long, with approximately straight sides, which are slightly narrowed in front of the eyes. Occipital angles only slightly rounded, the flattened portion of the occipital border, which extends almost the full width of the head, with a broad and very feeble median excavation clypeus feebly projecting, its anterior edge with a broad, rounded, and rather shallow median impression. Median lobe of the clypeus without carinae but with prominent longitudinal rugae at either side, approximately rectangular in outline and extending well back between the rather short frontal carinae. Frontal area triangular, slightly depressed, opaque. Mandibles large and triangular, the outer margin moderately and evenly curved, the junction between the outer and masticatory margins armed with two large blunt teeth which are set close together and form a small terminal lobe to the mandible, the remainder of the masticatory margin feebly and irregularly serrate. Eyes of moderate size with 16-18 facets in their greatest diameter, feebly convex and circular in outline, except for a small straight ventral portion. The posterior margin of the eye lies at the middle of the side of the head. The antennal scapes in repose fail to reach the occipital margin by a distance twice as great as their maximum diameter. Basal two-thirds of the scape viewed from front straight and thin, the apical third strongly swollen, with the tips turned slightly outwards. Funicular joints gradually increasing in thickness apically, all of about the same length except the basal and terminal joints, which are slightly longer than the rest.

Promesonotum, seen from above, with an evenly rounded anterior border which passes without distinct humeral angles into the straight sides, the latter converging strongly toward the mesoepinotal suture where they meet the short, transverse posterior border in a rather sharp angle. Sides of the thorax not constricted at the mesoepinotal suture, the epinotum subrectangular in outline, slightly narrower behind than in front and with the sides strongly sloping inward to the dorsum. Epinotal spines slender, feebly divergent, and shorter than the distance between their bases. Seen in profile, the promesonotum is evenly though feebly convex and notably higher than the epinotum to which it abruptly descends by means of a short, almost perpendicular posterior face. Mesoepinotal suture broad and prominent though not deeply impressed. Basal face of the epinotum with a short, straight anterior portion which forms a distinct angle with the longer, strongly slanting posterior portion. Declivous face of the epinotum short, only slightly more sloping than the posterior half of the basal face, the very wide angle between the two faces armed with short, straight, acute spines.

Petiole, in profile, with the thick anterior peduncle increasing in diameter toward the base of the node and bearing a prominent ventral lamella. Node small, somewhat inclined backwards, the summit blunt and rounded, the anterior face forming a very wide angle with the dorsum of the peduncle, the posterior face meeting the short, thick posterior peduncle at a sharper angle. Postpetiole in profile notably larger than the node of the petiole, its dorsum strongly gibbous and passing posteriorly to a very thick posterior peduncle; ventral face notably concave, with a marked, angular, ventral projection at its anterior border. Seen from above, the anterior portion of the peduncle of the petiole is notched at either side by an angular constriction. Posterior to these notches the petiole is bluntly cuneiform, widest behind the node, and one-half as wide as the suboval postpetiole. Gaster oval, its anterior border not flattened at the insertion of the postpetiole but with the portions immediately adjacent to the postpetiole bearing very short, even, parallel striae which give it the appearance of the milled edge of a coin. Femora rather strongly incrassated.

Head feebly shining, its anterior half covered with fine, subparallel rugae which are interrupted by numerous, coarse, punctures. On the posterior half of the head they are less prominent and more irregular, degenerating into wavy areas separating the numerous large, elongate punctures. Mandibles moderately shining, with somewhat coarser rugae than the head. Lateral portions of the clypeus finely punctate, the median lobe with a few longitudinal rugae at either side. Antennal scapes shagreened. Promesonotum less shining than the head, the dorsum with fine parallel striae, the sides dull and striate-granulose. On the epinotum the granulation almost completely replaces the striation except for certain portions of the pleura. Petiole and postpetiole densely granulose. Gaster shining, feebly shagreened, with numerous very small piligerous punctures.

Hairs on the body short, numerous, erect and golden. Their length is fairly uniform, except for a few somewhat longer ones on the petiolar nodes, promesonotum, and front of the head. The hairs on the genae, gula, and mentum are short and do not form ammochaetae. Hairs on the legs abundant, short, and erect. Antennal scapes with numerous fine short erect hairs. Funiculi with very fine hairs which are replaced by pubescence on the apical joints.

Color rich reddish or yellowish brown, the borders of the mandibles and the abdomen piceous brown.

References

  • Bolton, B. 1982. Afrotropical species of the myrmecine ant genera Cardiocondyla, Leptothorax, Melissotarsus, Messor and Cataulacus (Formicidae). Bulletin of the British Museum (Natural History). Entomology, 46: 307-370 (page 341, Combination in Messor)
  • Emery, C. 1895d. Beiträge zur Kenntniss der nordamerikanischen Ameisenfauna. (Schluss). Zool. Jahrb. Abt. Syst. Geogr. Biol. Tiere 8: 257-360 (page 307, worker described)
  • Emery, C. 1915k. Definizione del genere Aphaenogaster e partizione di esso in sottogeneri. Parapheidole e Novomessor nn. gg. Rend. Sess. R. Accad. Sci. Ist. Bologna Cl. Sci. Fis. (n.s.) 19: 67-75 (page 73, Combination in Novomessor)
  • Forel, A. 1917. Cadre synoptique actuel de la faune universelle des fourmis. Bull. Soc. Vaudoise Sci. Nat. 51: 229-253 (page 235, Combination in N. (Veromessor))
  • Ward, P.S., Brady, S.G., Fisher, B.L. & Schultz, T.R. 2014. The evolution of myrmicine ants: phylogeny and biogeography of a hyperdiverse ant clade (Hymenoptera: Formicidae). Systematic Entomology, DOI: 10.1111/syen.12090
  • Wheeler, W. M.; Creighton, W. S. 1934. A study of the ant genera Novomessor and Veromessor. Proc. Am. Acad. Arts Sci. 69: 341-387 (page 385, Combination in Veromessor)