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

Workers of V. stoddardi are solitary foragers that commence activities near dusk and forage through the night (M. Bennett, pers. comm.). Another observer indicated that colonies have long foraging columns (K.L. Jorda, pers. comm.), such that more information is needed to understand foraging biology of this species. Colonies probably contain 1,000–2,000 workers (Creighton, 1953; R.A. Johnson, pers. obs.). Workers are strongly polymorphic. Nests are often placed in hard clay soil and often have two to three entrances (Creighton, 1953). (Johnson et al., 2022)



This species is uniquely characterized by the following combination of features (Johnson et al., 2022):

  1. Head and mesosoma orangish-red to orangish-brown, gaster blackish-orange to blackish
  2. Medial lobe of clypeus lacking medial groove but with several lateral longitudinal rugae, medial lobe not thick and protuberant in profile, not elevated above lateral lobes in frontal view
  3. Mandibles with 8 teeth
  4. Antennal scape narrowest immediately distad of basal bend
  5. MOD distinctly less than OMD, OI < 25.0
  6. Ccephalic dorsum moderately shining between fine, widely spaced, longitudinal rugae; antennal fossa lacking concentric rugae
  7. Ppsammophore poorly developed; ventral surface of head capsule with scattered straight or evenly curved hairs, but J-shaped hairs mostly absent
  8. Dorsum of pronotum with fine, wavy to weakly irregular, longitudinal rugae; sides of pronotum with longitudinal rugae that fade to disappear posterad, posterior one-third often granulate; mesonotum mostly smooth and shining, lacking rugae or with longitudinal rugae that are distinctly weaker than those on dorsum of pronotum; mesopleura with rugae that traverse longitudinally to posterodorsally, interrugae weakly coriarious to moderately granulate
  9. Propodeal spines short, acuminate, length less than distance between their bases; infraspinal facet and propodeal declivity rugose or weakly to strongly coriarious, weakly to moderately shining
  10. Metasternal process large, narrowed laterally, slightly higher than long with angulate apex; anterior and posterior surfaces decline steeply; partly translucent (Figures 48–49)
  • Johnson et al., 2022, Fig. 48. Photograph of Veromessor stoddardi minor worker: (A) frontal view of head, (B) lateral view of body, and (C) dorsal view of body (CASENT0922825). Photographs by Michele Esposito from
  • Johnson et al., 2022, Fig. 49. Photograph of Veromessor stoddardi major worker: (A) frontal view of head, (B) lateral view of body, and (C) dorsal view of body (CASENT0922824). Photographs by Michele Esposito from


This caste is diagnosed by the following combination of features (Johnson et al., 2022):

  1. Head dark orangish brown to reddish-brown, gaster slightly lighter; pronotum, dorsal portion of anepisternum, mesoscutellum, propodeum dark orangish-brown; rest of mesosoma dark blackish-orange to blackish
  2. Medial lobe of clypeus lacking medial groove but with several lateral longitudinal rugae
  3. Mandibles with 8 teeth
  4. Dorsal surface of base of scape slightly flattened; maximum basal width of scape similar to maximum preapical width
  5. MOD slightly greater than OMD
  6. Cephalic dorsum with fine, wavy to irregular longitudinal rugae that fade to disappear near posterior margin; interrugae moderately shining
  7. Psammophore poorly developed
  8. Sides of pronotum weakly to moderately punctate between fine longitudinal rugae; mesoscutum and mesoscutellum smooth and shining with scattered piligerous punctures; anepisternum shining, weakly punctate between fine longitudinal rugae, both rugae and punctuation weak to absent ventrad; katepisternum mostly shining and superficially roughened with short, longitudinal striae anterad and posterad
  9. Sides of propodeum weakly shining and densely punctate between longitudinal and oblique rugae; propodeal spines triangular, acuminate, distinctly shorter than distance between their bases; infraspinal facet shining, superficially punctate above, propodeal declivity smooth and shining
  10. Metasternal process large, narrowed laterally, slightly higher than long with angulate apex; anterior and posterior surfaces decline steeply; partly translucent (Figure 50)
  • Johnson et al., 2022, Fig. 50. Photograph of Veromessor stoddardi alate queen: (A) frontal view of head, (B) lateral view of body, and (C) dorsal view of body (LACMENT370303). Photographs by Wade Lee from


This caste is diagnosed by the following combination of features (Johnson et al., 2022):

  1. Blackish brown, appendages light brown
  2. Medial lobe of clypeus abruptly descendant distad, disc weakly shining with coarse oblique to longitudinal rugae
  3. Mandibles with 3–4 teeth basad of preapical tooth
  4. Anterior ocellus above level of top of eyes
  5. Anepisternum weakly shining, finely punctate between closely spaced, moderately coarse, longitudinal rugae; katepisternum shinier, disc weakly roughened, posterad with moderately coarse oblique to longitudinal rugae
  6. Propodeum densely punctate between coarse, mostly longitudinal rugae, interrugae weakly shining; propodeal spines triangular, acuminate, length less than distance between their bases, (17) metasternal process distinctly higher than long, apex narrowly rounded
  7. Subpetiolar process short, elongate-triangular to spiniform or digitiform, apex acuminate to rounded (Figures1J, 51)
  • Johnson et al., 2022, Fig. 1. Photographs of the metasternal process on males of Veromessor: (A) V. andrei (CASENT4010823), (B) V. chamberlini (UCRC_ENT00500152), (C) V. chicoensis (CASENT0869853), (D) V. julianus (LACMENT359792), (E) V. lariversi (CASENT0761204), (F) V. lobognathus (LACMENT363986), (G) V. pergandei (CASENT0869850), (H) V. pseudolariversi (CASENT0869851), (I) V. smithi (LACMENT364071), and (J) V. stoddardi (LACMENT364102). Photographs by Robert Johnson from
  • Johnson et al., 2022, Fig. 51. Photograph of Veromessor stoddardi male: (A) frontal view of head, (B) lateral view of body, and (C) dorsal view of body (LACMENT364104). Photographs by Michele Esposito from

Identification Notes

The poorly developed psammophore distinguishes V. stoddardi from all congeners except Veromessor andrei and Veromessor chicoensis. Veromessor andrei is the only congener with a poorly developed psammophore that is likely to cooccur with V. stoddardi. The two species can be distinguished based on: (1) V. stoddardi has short propodeal spines (length less than the distance between their bases), (2) strongly polymorphic workers, and (3) weak, regular rugae on cephalic dorsum posterior to eyes and dorsum of pronotum. In V. andrei: (1) propodeal spines long (length > 3× the distance between their bases), (2) workers mostly monomorphic, and (3) notably coarse rugae on cephalic dorsum posterior to eyes and dorsum of pronotum. Veromessor stoddardi is most similar to the closely related species V. chicoensis, from which it can be distinguished by: (1) antennal scape narrowest immediately distad of basal bend; maximum basal width of scape about equal to maximum preapical width, and (2) in dorsal view, the mesonotum usually smooth and shining, rugae distinctly weaker than those on pronotum. In V. chicoensis: (1) antennal scape narrowest near midlength; maximum basal width of scape greater than maximum preapical width, and (2) in dorsal view, rugae on mesonotum similar to those on pronotum, interrugae weakly dull (also see discussion under P. chicoensis). (Johnson et al., 2022)

Workers of these two species display few consistent morphological differences, but queens and males differ in both morphology and size. Worker allometry is similar for both species (see above), but queens and males of V. stoddardi are distinctly larger than those of Veromessor chicoensis (Figure 19). A molecular phylogeny based on UCEs shows that both species form divergent, reciprocally monophyletic lineages (M.L. Borowiec, unpub. data, in Johnson et al., 2022).

  • Johnson et al., 2022, Fig. 19. Bivariate plots for workers, queens, and males of Veromessor chicoensis and V. stoddardi: (A) head width versus head length and (B) head width versus mesosoma length. Sample size for each caste is in parentheses.
  • Johnson et al., 2022, Fig. 55. Bivariate plots for workers showing head width versus head length (left panels) and mesosoma length versus pronotum width (right panels) for ecologically similar pairs of small colony species of Veromessor: V. lariversi and V. pseudolariversi (A–B), V. lobognathus and V. smithi (C–D), V. chicoensis and V. stoddardi (E–F). Note that the x-axis scale is the same for all panels on the left and for all panels on the right so that sizes can be compared directly across species groups. Sample size for each species is given in parentheses.
  • Johnson et al., 2022, Fig. 53. Eye area (mm2) (A), facet number (B), and mean facet diameter (μm) (C) for pale and dark colored species of Veromessor. Two species are pale (V. lariversi, V. pseudolariversi—open symbols and regular font), while the other eight species are dark (filled symbols and bold font). For each species, number of workers examined and number of colonies they were derived from is given in parentheses. Significant differences (P < 0.05) among species are denoted after each species name by the letters a–g: a > b > c > d > e > f > g; the three sets of letters for each species correspond to panels A, B, and C, respectively. Groupings are based on univariate F tests within MANCOVA followed by pairwise comparisons using a least significant differences test (see also Johnson & Rutowki, 2022).
  • Johnson et al., 2022, Fig. 56. Queen body size across species of Veromessor based on average head width, average head length, and average mesosoma length. Species are ordered (left to right) from shortest to longest mesosoma length.

Keys including this Species


Veromessor stoddardi occurs at elevations from 60–980 m, and it appears to be mostly restricted to soils with higher clay content (M. Bennett, pers. comm.). This species occurs in the Baja California desert, California coastal sage and chaparral, and California montane chaparral and woodlands ecoregions, as defined by Olson et al. (2001) (Figure 52). (Johnson et al., 2022)

  • Johnson et al., 2022, Fig. 52. Geographic distribution of Veromessor stoddardi. The larger black circle denotes the type locality.

Latitudinal Distribution Pattern

Latitudinal Range: 36° to 28°.

Tropical South
  • Source: Johnson et al., 2022

Distribution based on Regional Taxon Lists

Nearctic Region: United States (type locality).
Neotropical Region: Mexico.

Distribution based on AntMaps


Distribution based on AntWeb specimens

Check data from AntWeb

Countries Occupied

Number of countries occupied by this species based on AntWiki Regional Taxon Lists. In general, fewer countries occupied indicates a narrower range, while more countries indicates a more widespread species.

Estimated Abundance

Relative abundance based on number of AntMaps records per species (this species within the purple bar). Fewer records (to the left) indicates a less abundant/encountered species while more records (to the right) indicates more abundant/encountered species.


The following notes are provided by Johnson et al., (2022):

Gland chemistry has not been examined in V. stoddardi. Like other small-colony congeners, workers of V. stoddardi have a small pygidial gland reservoir and lack a textured tergal cuticle (Hölldobler et al., 2013).

Mating flights occur near dusk and post-dawn hours in June and July (Creighton, 1953; M. Bennett, pers. comm.). Nothing is known about mating frequency or colony founding.



The following information is derived from Barry Bolton's Online Catalogue of the Ants of the World.

  • stoddardi. Stenamma (Messor) stoddardi Emery, 1895c: 307 (w.) U.S.A. (California).
    • Type-material: syntype workers (number not stated).
    • Type-locality: U.S.A.: California, San Jacinto (T. Pergande).
    • Type-depositories: LACM, MCZC, MSNG, USNM.
    • Combination in Novomessor: Emery, 1915d: 73;
    • combination in Novomessor (Veromessor): Forel, 1917: 235; Emery, 1921f: 67;
    • combination in Messor: Wheeler, W.M. 1910g: 565; Bolton, 1982: 341 (in text);
    • combination in Veromessor: Wheeler, W.M. & Creighton, 1934: 385; Ward, et al. 2015: 73.
    • Status as species: Wheeler, W.M. 1910g: 565; Emery, 1915d: 73; Emery, 1921f: 67; Wheeler, W.M. & Creighton, 1934: 385 (redescription); Enzmann, J. 1947b: 152 (in key); Creighton, 1950a: 161; Smith, M.R. 1951a: 799; Smith, M.R. 1956a: 37 (in key); Smith, M.R. 1958c: 120; Smith, D.R. 1979: 1365; Wheeler, G.C. & Wheeler, J. 1986g: 38 (in key); Bolton, 1995b: 257; Ward, 2005: 66.
    • Distribution: U.S.A.

Type Material

  • Lectotype worker (designated by Johnson et al., 2022: 92) from San Jacinto, Riverside County, California, United States (Hyatt?) [USNM #55466] [USNMENT00922798] [USNM].
  • Paralectotype: 2 workers [LACM], 6 workers [USNM], #55466, UNITED STATES, California: Riverside County, San Jacinto (Hyatt?).

Wheeler and Creighton (1934) wrongly restricted the type locality of V. stoddardi to San Diego County, indicating, “the type series comes from several localities all in San Diego County, California. It seems preferable, for this reason to regard San Diego County as the type locality.” This is a remarkable statement given that none of the type material came from San Diego County. The locality cited in the description by Emery (1895) is San Jacinto, Riverside County, California, and this is the correct type locality, as noted by Creighton (1950). (Johnson et al., 2022)

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



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 based on Global Ant Biodiversity Informatics

  • Alatorre-Bracamontes, C.E. and M Vasquez-Bolanos. 2010. Lista comentada de las hormigas (Hymenoptera: Formicidae) del norte de México. Dugesiana 17(1):9-36
  • Dattilo W. et al. 2019. MEXICO ANTS: incidence and abundance along the Nearctic-Neotropical interface. Ecology
  • Johnson, R.A. and P.S. Ward. 2002. Biogeography and endemism of ants (Hymenoptera: Formicidae) in Baja California, Mexico: a first overview. Journal of Biogeography 29:1009–1026/
  • Mallis A. 1941. A list of the ants of California with notes on their habits and distribution. Bulletin of the Southern California Academy of Sciences 40: 61-100. 
  • Smith M. R. 1956. A key to the workers of Veromessor Forel of the United States and the description of a new subspecies (Hymenoptera, Formicidae). Pan-Pacific Entomologist 32: 36-38.
  • Vásquez-Bolaños M. 2011. Lista de especies de hormigas (Hymenoptera: Formicidae) para México. Dugesiana 18: 95-133
  • Wheeler W. M., and W. S. Creighton. 1934. A study of the ant genera Novomessor and Veromessor. Proceedings of the American Academy of Arts and Sciences 69: 341-387.