Veromessor
Creators: name: Johnson, Robert A.
name: Borowiec, Marek L.
name: Snelling, Roy R.
name: Cole, Arthur C.
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Formicidae
Veromessor

description: Synonymic list of species of Veromessor
V. andrei (Mayr, 1886): 448 (w.q.m.l.k*). Mexico (Baja California), United States (California, Oregon).
V. chamberlini (Wheeler, 1915): 410 (w.q.m.l). United States (California).
V. chicoensis Smith, 1956: 37 (w.q.m). United States (California).
V. julianus (Pergande, 1894): 164 (w.q.m). Mexico (Baja California, Baja California Sur).
V. lariversi Smith, 1951: 94 (w.q.m). United States (California, Nevada).
V. lobognathus (Andrews, 1916): 82 (w.q.m). United States (Arizona, Colorado, Idaho, Montana, Nevada, North Dakota, Oregon, South Dakota, Utah).
V. pergandei (Mayr, 1886): 448 (w.q.m). Mexico (Baja California, Baja California Sur, Sonora), United States (Arizona, California, Nevada).
V. pseudolariversi Johnson, Borowiec, Snelling & Cole (w.q.m). United States (California, Nevada). NEW SPECIES
V. smithi Cole, 1963: 678 (w.q.m). United States (Arizona, California, Colorado, Nevada, New Mexico, Oregon).
V. stoddardi (Emery, 1895): 307 (w.q.m). Mexico (Baja California), United States (California).
* w = worker, q = queen, m = male, l = larva, k = karyotype
Key to workers for species of Veromessor
1 Psammophore well developed, consisting of numerous, long, J-shaped hairs arranged in a distinct row along lateroventral margin of head (Figure 6E)............................................................................ 2
- Psammophore poorly developed, consisting of numerous, short to medium length hairs scattered across ventral surface of head; long J-shaped hairs lacking, or if present J-shaped hairs arranged in a V-shaped row not reaching posterior part of the lateroventral margin of head capsule, usually mixed with straight or evenly curved hairs (Figures 6A–D)............... 8
2 Anteromedial margin of clypeus with a small, blunt tooth or projection; in profile, eye narrowed below with a distinct ventral angle; body dark brownish-black to black.......................................................... pergandei
- Anteromedial margin of clypeus entire or concave, but lacking a small medial tooth or projection; in profile, eye rounded below; body usually concolorous yellowish or orangish-brown to rust colored, but never dark brownish-black to black.... 3
3 Propodeal spines short, length <0.5× maximum diameter of the eye (MOD)...................................... 4
- Propodeal spines long, length> 1.0× MOD................................................................ 6
4 Larger (HW = 1.33–1.61 mm); maximum basal width of scape greater than maximum preapical width; body concolorous dark yellowish-orange or orangish-brown to rust colored; mandible with 8 teeth, rarely 9........................... smithi
- Smaller (HW = 0.93–1.37 mm); maximum basal width of scape less than maximum preapical width; body light yellowish to yellowish-orange or yellowish-red, gaster often slightly darker; mandibles with 7 teeth.............................. 5
5 Anteroventral margin of postpetiole interrupted by a transverse ridge, in profile appearing as a minute process, margin weakly concave anterior to process; in dorsal view, pronotum with weak, discontinuous to continuous, wavy to irregular transverse rugae; dorsum of mesonotum with one to few weak, wavy to irregular, usually discontinuous longitudinal rugae.................................................................................................. pseudolariversi
- Anteroventral margin of postpetiole continuous, in profile lacking a minute process; in dorsal view, pronotum and mesonotum arugose, weakly to strongly coriarious to punctulate-granulate........................................... lariversi
6 Base of scape weakly widened; maximum basal width of scape less than maximum preapical width; cephalic dorsum with fine, closely spaced, regular to weakly wavy, longitudinal rugae, interrugae moderately to strongly shining; metasternal process about twice as long as high, apex nearly flat.......................................................... julianus
- Base of scape distinctly widened; maximum basal width of scape greater than maximum preapical width; cephalic dorsum with prominent widely spaced, mostly regular longitudinal rugae, interrugae shining or if rugae closely spaced, then rugae strongly irregular to nearly rugoreticulate, interrugae strongly granulate, dull; metasternal process as long as to slightly longer than high, apex bluntly rounded.................................................................................. 7
7 Propodeal spines longer, length about 2.0× the distance between their bases; cephalic dorsum with prominent, widely spaced, mostly regular longitudinal rugae, interrugae shining; sides of pronotum with wavy to regular rugae, interrugae smooth and strongly shining; posterior margin of frontal lobes notably constricted; in frontal view, base of scape asymmetrical with ventral portion of anterior edge greatly expanded compared to dorsal edge (Figure 12A)......................... chamberlini
- Propodeal spines shorter, length only slightly greater than to rarely 1.5× the distance between their bases; cephalic dorsum with closely spaced, strongly irregular rugae to nearly rugoreticulate, interrugae strongly granulate, dull; sides of pronotum with weakly to strongly irregular rugae to weakly rugoreticulate, interrugae moderately to strongly granulate, dull to weakly shining; posterior margin of frontal lobes not constricted; in frontal view, base of scape mostly symmetrical with ventral and dorsal portions of anterior edge similar in size or with dorsal edge expanded more than ventral edge (Figure 12B)......... lobognathus
8 Propodeal spines long, in dorsal view, length> 2.5× as long as distance between their bases and> 2.5× MOD; hairs on scape variable in length, suberect to erect, longest hairs about 0.3–0.4× MOD; anterodorsal margin of pronotum with one to several coarse, irregular, transverse rugae; workers mostly monomorphic.......................................... andrei
- Propodeal spines short, in dorsal view, length less than to about as long as distance between their bases and less than to about as long as MOD; hairs on scape mostly uniform in length, subdecumbent to suberect, longest hairs about 0.1–0.2× MOD; anterodorsal margin of pronotum with weak, wavy to regular longitudinal or oblique rugae, rugae rarely transverse; workers polymorphic......................................................................................... 9
9 In dorsal view, rugae on mesonotum similar to those on pronotum, interrugae weakly dull to shining; antennal scape narrowest near midlength............................................................................... chicoensis
- In dorsal view, rugae on mesonotum distinctly weaker than those on pronotum, interrugae shining; antennal scape narrowest immediately distad of basal bend................................................................. stoddardi
Key to queens for species of Veromessor
1 Psammophore well developed, consisting of numerous, long, J-shaped hairs arranged in a distinct row along lateroventral margin of head....................................................................................... 2
- Psammophore poorly developed, consisting of numerous, short to medium length hairs scattered across ventral surface of head; long J-shaped hairs sparse or lacking..................................................................... 8
2 Anteromedial margin of clypeus with a small, blunt tooth or projection; in posterodorsal view, medial and posteromedial surface of petiolar node usually weakly to moderately depressed or concave; concolorous blackish to black; propodeal spines short and triangular, length much less than width at base and length less than distance between their bases...... pergandei
- Anterior margin of clypeus entire, lacking a small medial tooth or projection; in posterodorsal view, medial and posteromedial portion of petiolar node usually evenly rounded; concolorous orangish or orangish-brown to reddish-brown or bicolored with head and mesosoma orange and gaster blackish or if concolorous dark brownish-black, then propodeal spines elongate, length greater than width at base and length similar to distance between their bases...................................... 3
3 Maximum basal width of scape greater than maximum preapical width.......................................... 4
- Maximum basal width of scape less than to similar to maximum preapical width................................... 6
4 Rugae on cephalic dorsum becoming faint to disappearing above level of ocelli, lacking on posterior margin; in profile, rugae absent posterior to eyes........................................................................... smithi
- Rugae on cephalic dorsum continuing to posterior margin; in profile, rugae present posterior to eyes................... 5
5 Posterior margin of frontal lobes notably constricted; in frontal view, base of scape asymmetrical with ventral portion of anterior edge greatly expanded compared to dorsal edge............................................. chamberlini
- Posterior margin of frontal lobes not notably constricted; in frontal view, base of scape mostly symmetrical with ventral and dorsal portions of anterior edge similar in size or with dorsal edge expanded more than ventral edge......... lobognathus
6 Rugae on cephalic dorsum continue onto posterior margin; propodeal spines elongate, length greater than width at base and length similar to distance between their bases; restricted to the Baja California peninsula of Mexico ............. julianus
- Rugae on cephalic dorsum fade and disappear posterad, posterior margins smooth and shining; propodeal spines triangular, length less than width at base and length much less than distance between their bases; only known from California and Nevada ............................................................................................. 7
7 In profile, anteroventral margin of postpetiole interrupted by a minute process, margin weakly concave anterior to process; smaller (HW = 1.21–1.36 mm; ML = 1.95–2.04 mm); longitudinal rugae present over most to all of katepisternum............................................................................................... pseudolariversi
- In profile, anteroventral margin of postpetiole continuous, lacking a minute process; larger (HW = 1.53–1.62 mm; ML = 2.78–2.98 mm); longitudinal rugae present on anterior and posterior portion of katepisternum, central portion lacking rugae.............................................................................................. lariversi
8 Dorsal base of scape with a well developed, horizontal flange; mesoscutellum with numerous longitudinal rugae; medial lobe of clypeus with several coarse longitudinal rugae; hairs on scape variable in length, longest hairs suberect to erect... andrei
- Dorsal base of scape may be broadened but lacking a horizontal flange; mesoscutellum arugose, smooth and shining; medial lobe of clypeus smooth and shining, lacking rugae, or rugae occasionally near anterior margin; hairs on scape similar in length, all hairs decumbent................................................................................... 9
9 Smaller (HW 1.39–1.58 mm; ML = 2.10–2.26 mm); katepisternum with longitudinal rugae; hairs on first gastral tergum longer, length of longest hairs approaching to equaling MOD; rugae on cephalic dorsum continue onto posterior margin..................................................................................................... chicoensis
- Larger (HW = 1.61–1.75 mm; ML = 2.77–2.97 mm); katepisternum mostly smooth and shining; hairs on first gastral tergum shorter, length of longest hairs <0.4–0.5× MOD; rugae on cephalic dorsum fade to disappear on posterior margin..................................................................................................... stoddardi
Key to males for species of Veromessor
1 Dorsum of mesoscutum smooth and shining, rugae and/or striae lacking......................................... 2
- Rugae and/or striae cover some to most of dorsum of mesoscutum.............................................. 3
2 Mandibles with 2–3 teeth basad of preapical tooth; in profile; metasternal process triangular, acuminate (Figure 1E).................................................................................................... lariversi
- Mandibles with 1–2 minute denticles or teeth basad of preapical tooth; metasternal process elongate, slender, with a withered look (Figure 1I)................................................................................. smithi
3 Psammophore consists of numerous, long, J-shaped hairs along lateroventral margin of head and larger (HW = 1.23–1.46 mm; PPW = 0.98–1.29 mm; EL = 0.50–0.59)........................................................... pergandei
- Psammophore consists of numerous hairs scattered across ventral surface of head and/or smaller (HW = 0.68–1.00 mm; PPW = 0.37–0.70 mm; EL = 0.33–0.41 mm).................................................................... 4
4 Occurring east of the Sierra Nevada and north of San Gabriel Mountains of California and east into Nevada, Arizona, and further east.......................................................................................... 5
- Occurring in southwestern Oregon, California west of the Sierra Nevada, southwestern California, and the Baja California peninsula, Mexico .................................................................................... 6
5 Body blackish to black; in profile, anteroventral margin of postpetiole interrupted by small transverse ridge that appears as a minute process; anepisternum and katepisternum rugose.......................................... pseudolariversi
- Body light brown to brown; in profile, anteroventral margin of postpetiole continuous, lacking a minute process; anepisternum and katepisternum mostly smooth and shining to coriarious......................................... lobognathus
6 In profile, propodeum evenly rounded, lacking tubercles, denticles, or enlarged rugae............................... 7
- In profile, propodeum not evenly rounded, profile interrupted by denticles, tubercles, or enlarged rugae................ 8
7 Restricted to the Baja California peninsula of Mexico .................................................. julianus
- Restricted to California south and west of San Gabriel Mountains..................................... chamberlini
8 Anepisternum rugose............................................................................. andrei
- Anepisternum contiguously punctate-granulate to mostly smooth to roughened or with faint rugae..................... 9
9 Anepisternum and katepisternum contiguously punctulate-granulate, anepisternum occasionally with scattered rugae; sides of propodeum contiguously punctulate-granulate with scattered, weak longitudinal rugae; in profile, area posterior to eyes and posterior corners strongly punctulate-granulate with several weak longitudinal rugae....................... chicoensis
- Anepisternum mostly smooth to roughened or with faint rugae; katepisternum roughened or coriarious; in profile, area posterior to eyes and posterior corners with prominent longitudinal rugae, interrugae moderately punctulate-granulate..... stoddardi
description: Published as part of Johnson, Robert A., Borowiec, Marek L., Snelling, Roy R. & Cole, Arthur C., 2022, A taxonomic revision and a review of the biology of the North American seed-harvester ant genus Veromessor (Hymenoptera: Formicidae: Myrmicinae), pp. 1-115 in Zootaxa 5206 (1) on pages 8-12, DOI: 10.11646/zootaxa.5206.1.1, http://zenodo.org/record/7318829