Veromessor pergandei
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
Veromessor pergandei

description: Veromessor pergandei
(Figures 1G, 6E, 37–40)
Distribution— Figure 41A
Aphaenogaster pergandei Mayr, 1886: 448 (worker). Syntypes examined: 9 workers [USNM] #55467, UNITED STATES, California: no location, May 1884; Wheeler and Creighton, 1934: 376 (minor worker, queen, male); Wheeler & Wheeler, 1972: 240 (larvae); Wheeler & Wheeler, 1987: 303, figs. 1-6 (larvae). See also Wheeler and Creighton, 1934: 374, plate II, fig. 3. USNM worker here designated LECTOTYPE [USNMENT00531691].
Stenamma (Veromessor) pergandei (Mayr); Emery, 1895: 307 (first combination in Stenamma [Veromessor]).
Novomessor pergandei (Mayr); Emery, 1915: 73 (first combination in Novomessor).
Messor (Veromessor) pergandei (Mayr); Forel, 1917: 235 (first combination in Messor ([Veromessor]).
Veromessor pergandei (Mayr); Wheeler and Creighton, 1934: 374 (first combination in Veromessor).
Novomessor (Veromessor) pergandei (Mayr); Enzmann, 1947: 152 (first combination in Novomessor [Veromessor]).
Veromessor pergandei (Mayr); Creighton, 1950: 157 (revived combination in Veromessor).
Messor pergandei (Mayr); Bolton, 1982: 341 (revived combination in Messor).
Veromessor pergandei (Mayr); Ward, Brady, Fisher, and Schultz, 2015: 13 (revived combination in Veromessor).
Worker diagnosis. This species is uniquely characterized by the following combination of features: (1) concolorous dark brownish-black to black, (2) medial lobe of clypeus thick and protuberant in profile, elevated above lateral lobes in frontal view with a blunt medial tooth or projection along with several coarse, lateral, longitudinal rugae, (3) mandibles with 8 teeth, (4) dorsal base of scape weakly flattened, weakly widened; maximum basal width of scape much less than maximum preapical width, (5) MOD less than to greater than OMD; in profile, lower margin of eye narrowed and abruptly rounded to bluntly subangulate, OI <29.0, (6) cephalic dorsum with fine, closely spaced, longitudinal rugae on medial area from clypeus to near posterior margin of eyes and below eyes, rest of head weakly to strongly coriarious, moderately shining; rugae on smaller workers usually more restricted to lacking, (7) psammophore well developed; ventral surface of head capsule with many long J-shaped hairs arranged in a distinct row around the outer margin of the ventral surface of head capsule, (8) mesosoma lacking rugae, moderately to strongly coriarious, weakly to moderately shining, (9) propodeal spines acuminate, not curved in profile, not curved in dorsal view to weakly curved inward for workers with longer spines; length less than the distance between their bases; infraspinal facet and propodeal declivity moderately to strongly coriarious, weakly to moderately shining, and (10) metasternal process small, more or less coniform, about as long as high, apex bluntly rounded (Figures 6E, 37–38).
Measurements. lectotype (n = 62). HL 1.77 (1.09–1.89); HW 1.72 (1.10–2.03); MOD 0.43 (0.27–0.49); OMD 0.42 (0.22–0.50); SL 1.38 (0.96–1.57); PNW 1.04 (0.61–1.22); HFL 1.59 (1.32–2.23); ML 2.07 (1.21–2.41); PW 0.31 (0.20–0.42); PPW 0.47 (0.28–0.67). Indices: SI 80.23 (72.45–94.59); CI 97.18 (83.62–111.69); OI 25.00 (20.00–28.46); HFI 92.44 (87.42–130.00).
Queen diagnosis. This caste is diagnosed by the following combination of features: (1) head and mesosoma blackish to black; gaster dark brown, (2) medial lobe of clypeus thick and protuberant in profile, elevated above lateral lobes in frontal view with a blunt medial tooth or projection along with several coarse, lateral, longitudinal rugae, (3) mandibles with 8 teeth, (4) dorsal base of scape weakly flattened and weakly widened; maximum basal width of scape much less than maximum preapical width, (5) MOD distinctly less than OMD, (6) cephalic dorsum with fine, closely spaced, longitudinal rugae that often fade or disappear near posterior margin; interrugae weakly to moderately coriarious, weakly shining, (7) psammophore well developed, (8) sides of pronotum smooth and shining, often with fine, closely spaced longitudinal rugae along posterior margin; mesoscutum and mesoscutellum smooth and shining with scattered piligerous punctures, rarely with lateral longitudinal striae on mesoscutum; mesopleura moderately coriarious, but often with fine rugae anterad on anepisternum and posterad on katepisternum, (9) propodeum with fine, longitudinal and oblique rugae, interrugae moderately punctulate, weakly shining; propodeal spines short, triangular, bluntly tipped; length much less than the distance between their bases; infraspinal facet and propodeal declivity smooth and shining to moderately to strongly coriarious, weakly shining, and (10) metasternal process small, elongate-triangular, slightly higher than long, apex bluntly subangulate (Figure 39).
Measurements. (n = 12). HL 1.78–2.04; HW 1.86–2.30; MOD 0.48–0.60; OMD 0.34–0.48; SL 1.48–1.74; HFL 1.79–2.39; ML 3.32–4.01; PW 0.42–0.64; PPW 0.71–0.90. Indices: SI 66.37–83.33; CI 100.00–117.42; OI 23.77–30.73; HFI 87.44–117.19.
Male diagnosis. This caste is diagnosed by the following combination of features: (11) color blackish, (12) medial lobe of clypeus thickened and abruptly descendant along anterior margin; anterior margin evenly to abruptly concave medially, (13) preapical tooth small, mandibles with 1–3 small triangular denticles or teeth basad of preapical tooth, (14) anterior ocellus level with top of eyes, (15) mesopleura weakly shining, strongly coriarious to strongly punctate, anepisternum with some very fine, longitudinal rugae or distinctly lineopunctate, (16) sides of propodeum strongly punctate-granulate between rugae; propodeal teeth absent or very short and obtuse; in profile, juncture of dorsum of propodeum and propodeal declivity rounded, (17) metasternal process longer than high, rounded in profile, and (18) subpetiolar process small and obtuse to large and triangular with apex rounded (Figures 1G, 40).
Measurements. (n = 12). HL 1.14–1.48; HW 1.23–1.46; MOD 0.50–0.59; OMD 0.19–0.24; SL 0.52–0.69; HFL 1.94–2.58; ML 2.84–3.90; PW 0.57–0.73; PPW 0.98–1.29; AOD 0.11–0.16; IOD 0.38–0.44; OOD 0.42–0.51. Indices: SI 39.69–51.15; CI 95.52–109.52; OI 36.99–44.35; HFI 135.66–193.13.
Additional material examined. MEXICO: Baja California: 2 mi W Laguna Salada, 200’, Jan 9, 1993 (RAJC); 5.0 mi S Hwy 3 to Mike’s Sky Ranch, 3600’, Mar 17, 2003 (RAJC); San Fernando, Jul 31, 1938 (USNM); Calamajué (as Calamujuet), no date (USNM); San Julio, no date (USNM); Hwy 3 at 12.8 mi E [Colonia] Lazaro Cardenas, Feb 28, 1992 (RAJC); 18.55 mi SE [Colonia] Lazaro Cardenas, Feb 26, 1992 (RAJC); Hwy 3 at 1 mi SE [Colonia] Lazaro Cardenas, Feb 26, 1992 (RAJC); Hwy 3 at 2.7 mi NW [Colonia] Lazaro Cardenas, Feb 26, 1992 (RAJC); San Felipe, Aug 23, 1959 (UAIC); Valle San Felipe, 1360’, Mar 4, 1998 (RAJC); 5.9 mi SE San Felipe at 1 mi W Punta Estrella, 100’, Feb 26, 1992 (RAJC); 6 mi W Jct Hwys 3 & 5, Feb 26, 1992 (RAJC); 0.3 mi S La Puerta, Feb 23, 1993 (RAJC); 0.5 mi W Huerfanito, 50’, Mar 9, 1992 (RAJC); Bahía de los Ángeles, 10’, Jan 9, 1991 (LACM; RAJC); 11.5 mi S Bahía de los Ángeles, Mar 9, 1992 (RAJC); 24.4 mi SE Bahía de los Ángeles, 300’, Mar 9, 1992 (RAJC); Hwy 1 at 11.65 mi W Bahía de los Ángeles, Mar 9, 1992 (RAJC); Hwy 1 at 18.15 mi W Bahía de los Ángeles, Mar 9, 1992 (RAJC); 19 km NW Bahía de los Ángeles, Jun 1, 1997 (UCDC); Hwy 1 at 7 km S Jct to Bahía de los Ángeles, Jan 6, 1991 (RAJC); Hwy 1 at 7 mi S Bahía de los Ángeles turnoff, Jan 6, 1991 (LACM; RAJC); 14 km ENE Jct Hwy 1 & rd to Bahía de los Ángeles, 480 m, Apr 6, 1998 (UCDC); 14.7 mi NW El Progreso, 960’, Mar 10, 1992 (RAJC); 2.5 mi NE El Progreso, 960’, Jan 29, 1995 (RAJC); 38.5 mi NW Catavina at 1 mi N El Progreso, Feb 10, 1993 (RAJC); 5.2 mi W Catavina, 1250’, Feb 14, 1997 (RAJC); 30.9 mi S Puertocitos, 50’, Feb 27, 1992 (RAJC); 41.7 mi S Puertocitos, 50’, Feb 27, 1992 (RAJC); 5 mi W Playa San Rafael, Mar 9, 1992 (RAJC); 2.3 mi NW Las Arrastras, 1150’, Feb 27, 1992 (RAJC); 6.5 mi N Las Arrastras de Arriola, 1000’, Feb 19, 1994 (RAJC); 7.7 mi SE Las Arrastras, 1450’, Feb 27, 1992 (RAJC); 8.5 mi N Rancho Arrastras, 820’, Jan 25, 1995 (RAJC); 7 mi N Las Arrastras de Arriola, Jun 8, 1967 (LACM); E base Sierra San Pedro Martir at Trailhead to Canyon Diablo, 1260’, Mar 4, 1998 (RAJC); Hwy 1 at 3.3 mi E Ejido Alfredo V. Bonfil, Feb 12, 1993 (RAJC); 6 mi NW Rancho Santa Ynez, 1800 ’, Jan 10, 1976 (CIDA); 9 km NW Rancho Santa Ines, 550 m, Apr 12, 1997 (CIDA); Valle Montevideo at 18 km W Bahía de los Ángeles, 380 m, no date (CIDA); SW end of Isla de la Guarda, 60 m, Jul 30, 1996 (UCDC); Cañon de Guadalupe, 550 m, Mar 30, 2001 (UCDC); 27 km W Punta Arena at 19 km N San Borja, Apr 9–10,1976 (UCDC). Baja California Sur: 1 mi W El Mesquital, Feb 16, 1993 (RAJC); 16 km E San Ignacio in Santa María Wash, Jan 9, 1991 (RAJC); 16 km SE San Ignacio, Jan 9, 1991 (LACM; RAJC); Hwy 1 at 15.1 mi E Guamúchil, Feb 29, 1992 (RAJC); Hwy 1 at 24.2 mi NW Santa Rosalía, 1450 ’, Mar 13, 2002 (RAJC). Sonora: Mpio. Caborca: Río Asunción & Cerro Cañedo, 2.8 km (by air) ESE of Caborca, 305 m, Jan 17, 2016 (RAJC). Mpio. Cucurpe: Rancho Puerto Blanco at Cerro Proveedora, 8.2 km (by air) WSW Caborca, 260 m, Feb 14, 2010 (RAJC). Mpio. General Plutarco Elías Calles: 6.4 km (by air) SW Jct Hwys 2 & 8, 445 m, Mar 1, 2012 (RAJC); Sierra los Tanques at 5.3 km (by air) WSW Jct Hwys 2 & 8, 410 m, Feb 26, 2013 (RAJC); Sierra los Tanques at 6.8 km (by air) SW Jct Hwys 2 & 8, 415 m, Feb 27, 2013 (RAJC); 2.8 mi W Los Vidrios, 960’, Mar 11, 1992 (RAJC). Mpio. Hermosillo: 6.5 km (by air) NNE center Hermosillo, 380 m, Dec 26, 2011 (RAJC); Hermosillo, Aug 12, 1959 (UAIC); SW Hermosillo nr Estadio de Sonora, 185 m, Feb 11, 2014 (RAJC); Arroyo el Chiltepín at 17 km NNE Hermosillo, 270 m, Mar 3, 2012 (RAJC); Siete Cerros at 8.6 km (by air) ENE Miguel Alemán, 90 m, Jan 19, 2016 (RAJC); Hwy 15 at 14 km N Hermosillo, 320 m, Oct 3, 2010 (RAJC); Cerrito de la Virgen at 5 km SSW Hermosillo, 285 m, Nov 10, 2010 (RAJC); Isla Tiburón at Bahía Sausal, 5 m, Dec 18, 1997 (UCDC). Mpio. La Colorada: 18.9 km (by air) S Cobachi, 425 m, Oct 18, 2011 (RAJC). Mpio. Mazatán: 2.3 km (by air) ESE Mazatán, 560 m, Jun 18, 2012 (RAJC). Mpio. Puerto Peñasco: Pinacate Reserve at Tecolote Campground, 215 m, Mar 4, 2012 (RAJC); Pinacate Reserve on Rd to Tecolote Camground at 49.5 km (by air) W Sonoyta, 210 m, Mar 4, 2012 (RAJC); Pinacate Reserve at Crater Elegante, 295 m, Mar 5, 2012 (RAJC); Pinacate Biosphere Reserve at Pápago Tanks, 210 m, Feb 24, 2013 (RAJC); Pinacate Biosphere Reserve at Cerro Lava, 235 m, Feb 25, 2013 (RAJC); Pinacate Reserve on rd to Visitor Center, S Sierrra Blanca, 70 m, Mar 5, 2012 (RAJC); Pinacate Desert, no date, 1982 (LACM). Mpio Pitiquito: Puerto Libertad, Jul 26, 1945 (USNM); 28.6 mi NE Puerto Libertad, 1570’, May 29, 1994 (RAJC). Mpio. Rayón; 8.0 km (by air) SSE Rayón, 535 m, Feb 4, 2011 (RAJC); 11.5 mi S Seri Desemboque, 30’, Nov 29, 1996 (RAJC). Mpio. San Luis Río Colorado: 36.6 km (by air) SE El Golfo de Santa Clara, 15 m, Feb 27, 2017 (RAJC). Mpio. Trincheras: El Boludo, no date (USNM). UNITED STATES: Arizona: La Paz Co.: 6 mi W Bouse, Mar 20, 1980 (UAIC); Vicksburg at 0.1 mi N Jct I-10, 1170 ’, Apr 24, 2018 (RAJC); Ehrenberg, 260’, Apr 24, 2018 (RAJC). Maricopa Co.: Arlington, Jun 16, 1919 (USNM); Tempe in Kyrene area, Mar 6, 1928 (UAIC: USNM); Tempe, May 1905 (UAIC); 4 mi SE Vulture Mine, 1960’, Nov 8, 1993 (RAJC); I-10 at Salome Rd exit, 1230’, May 18, 1993 & Sep 28, 2018 (RAJC); Salt River Recreation Area at Phon D Sutton, 1350’, Jan 16, 1993 (RAJC); Chandler, Dec 25, 1936 (LACM); Phoenix, Mar 24, 1933 (USNM); North Scottsdale, Feb 27, 1986 (UCDC); Gila Bend, Nov 22, 1932 (UAIC); Gila Bend Mtns, Aug 8, 1917 (UAIC); Hwy 85 at 10.9 mi S Jct I-10, 920’, May 3, 2018 (RAJC). Mohave Co.: Detrital Valley, 2040’, Apr 28, 1993 (RAJC); 4 mi E Littlefield, 2000’, Oct 9, 1976 (UAIC). Pima Co.: College Park, Tucson, Feb 13–Mar 23, 1933 (UAIC); Tucson, May 1905 & May 22, 1909 & Nov 22, 1910 & Dec 26, 1934 & Sep 19, 1935 & Mar 20, 1938 & no date (UAIC; USNM); 12 mi N Tucson, Mar 20, 1973 (LACM); Tucson Mtns (T13S, R11E, Sect 9), Aug 2, 1972 (CIDA). Pinal Co.: 25 mi S Phoenix, May 17, 1932 (USNM); McCartney Rd at 0.7 mi E I-10, 1430 ’, Feb 21, 2001 (RAJC); 2.0 mi E Jct I-10 & McCartney Rd, 1430’, Apr 29, 2005 (RAJC); 1.0 mi E Jct McCartney Rd & I-10, 1450 ’, Feb 11, 1991 (RAJC); 1.0 km N Jct I-10 & McCartney Rd, 1470’, Aug 26, 2014 (RAJC); 7 km E Casa Grande, Feb 11, 1991 (LACM; RAJC); 1.2 km NE Jct I-10 & McCartney Rd, 1440’, Feb 15, 2018 (RAJC); Hwy 79 at 0.1 mi S Tom Mix Monument, 2360’, Dec 4, 2005 (RAJC); 8.4 mi SW Picacho, 1550’, Jul 6, 2012 (RAJC). Yuma Co.: Yuma (as Youma), no date (USNM); Yuma, May–Jun, 1958 (UAIC); 4 mi SE Yuma, Feb 28, 1960 (UCDC); Mohawk Dunes, May 11–16, 1996 & Jun 10–24, 1996 (UAIC); Mohawk Dunes at 9.7 mi E Tacna, 460’, Mar 21, 2001 (RAJC); Topock, Apr 14, 1926 (UCDC); nr railroad at Dateland, 460’, Dec 16–21, 2010 & Oct 3, 2018 (RAJC: UCDC); 1 mi NE Dateland, 460’, Dec 18, 1992 (RAJC); 9 mi E San Luis, Feb 18, 1980 (UAIC); Yuma at Araby Rd at 0.2 mi N I-8, 190’, Oct 3, 2018 (RAJC). No county: no loc, no date (USNM); Gila Desert, Apr 6, 1935 (LACM). California: Fresno Co.: 27 km SSE (202 o) Mendota, 200 m, Mar 28, 2005 (UCDC); Jacalitos Canyon, Mar 25, 1967 (UCDC); Monvero Dunes Research Nature Area, 300 m & 585 m, Mar 23, 2015 (MLBC; MMPC). Imperial Co.: 9.3 mi S Walter’s Camp, Apr 10–11, 1998 (UCDC): Glamis Dunes, Dec 16, 1982 (UCDC); Glamis Dunes at 6 mi N Ogilby, Mar 19, 1980 (UAIC); Glamis, 300’, Oct 3, 2018 (RAJC); Fort Yuma, Apr 29, 1909 (USNM); 8 mi E Calipatria, Nov 12, 1921 (USNM); Government Wells near Coyote Wells, 0’, Jul 29, 1917 (USNM); Salton Sea, no date (USNM); Salton Sea, Mecca Beach Campground, - 60 m, Apr 18, 2014 (MLBC); Coyote Wash, Mar 28, 1919 (USNM); Dixieland, Jul 24, 1917 (USNM); Coyote Mtns, Painted Gorge, Mar 12–13, 1994 (LACM); Ocotillo, 370’, Apr 25, 2018 (NHMW; RAJC); 2.8 mi NNW Ocotillo, 300’, Feb 28, 1999 (LACM); 6.9 mi SSE Ocotillo, 320’, Feb 28, 1999 (LACM); Algodones Dunes, Ogilby Rd at 0.6 km S I-8, 62 m, Mar 11, 2009 (UCDC); Algondones Dunes, 90 m, Sept 11–15, 2007 & Apr 28–May 2, 2008 (UCDC); no loc, no date, 1911 (USNM). Inyo Co.: Ballarat, Mar 27, 1961 (UCDC); 6 mi W Ballarat, Apr 5, 1931 (USNM); Racetrack, Death Valley National Monument, 3700’, Mar 26, 1969 & Mar 1, 1970 (UAIC); Ubehebe Crater, Death Valley National Monument, Mar 19, 1931 (USNM); Death Valley National Monument, Jul 2, 1944 (USNM); Grapevine Ranger Station, Death Valley National Monument, 2300’, Oct 30–Nov 27, 1968 & Mar 12, 1969 & Jun 7–21, 1973 (RAJC; UAIC); 6 km N Badwater, Death Valley National Park, 200 m, Mar 26, 1998 (UCDC); 5 km N Ashford Mill, Death Valley National Park, 60 m, Mar 26, 1998 (UCDC); Cottonwood Canyon, Death Valley National Park, 250 m, Mar 27, 1998 (UCDC); 12.5 km SE Stovepipe Wells, - 15 m, Dec 27, 2012 (MMPC); Death Valley (no loc), Oct 20, 1938 & Apr 16, 1976 (LACM; UCDC); Hanaupah Canyon Rd, 330 m, Mar 26, 1998 (UCDC); Hwy 168 at 1 mi E Big Pine, 1200’, Jul 22, 1992 (RAJC); 2.2 mi SW Independence, 4620’, May 24, 2008 (RAJC); Saline Valley Dunes at 30 km E Independence, May 26, 1993 (UCDC); Furnace Creek, Jan 11, 1981 (UCDC); 5.5 km WNW Furnace Creek, - 80 m, Dec 24, 2012 (MMPC); Grapevine Mtns, Titus Canyon, Feb 12, 1967 (LACM); 1 mi W Jct Hwy 395 & Road J41, 3000’, Feb 16, 1985 (UCDC). Kern Co.: Boron, Jul 19, 1988 (UCDC); Edwards, Jul 20, 1988, UCDC); Mohave, Nov 11, 1914 & May 1, 1952 & no date, 1976 (UCDC; USNM); Bakersfield, Apr 3–6, 1938 (LACM; USNM); Ricardo, Nov 8, 1929 (USNM); Inyokern, Mar 21, 1931 (USNM); 2 km ESE Ricardo, Red Rock Canyon State Park, 740 m, 16 Mar 2003 (UCDC); Hwy 223 at 4 mi E Arvin, Jun 12, 1971 (LACM); Tehachapi, Jul 18, 1931 (LACM); Sand Canyon at 3 mi W Brown, Mar 30, 1963, (UCDC); Red Rock Canyon State Park, 800 m, Mar 18, 2003 (UCDC); China Lake, Jul 21, 1988 (UCDC). Kings Co.: Kettleman, Jun 30, 1988 (UCDC); 4 mi S Kettleman Canyon, Nov 17, 1959 (LACM). Los Angeles Co.: Claremont, no date & Dec 8, 1910 & Apr 1921 (UAIC; UCDC; USNM); Acton at 12 mi S Palmdale, 2720’, May 3, 2001 (UCDC); Los Angeles, no date (USNM); Glendale, May 16, 1941 (UCDC); no loc, no date (USNM). Orange Co.: Corona del Mar, Apr 1, 1932 (USNM). Riverside Co.: Palm Canyon, Jun 22, 1931 & no date, 1956 (USNM); 1000 Palms Canyon, Mar 4, 1940 (LACM); Elsinore, Jan 4, 1919 (USNM); San Jacinto, no date (USNM); Palm Springs, Mar 23–25, 1918 & Apr 15, 1930 & Aug 24, 1944 (UAIC; USNM); SE of Palm Springs, Dec 1, 1930 (USNM); Coachella Valley at Garnet, no date (USNM); Painted Canyon, Mar 8, 1930 (USNM); Whitewater, Apr 13, 1963 (LACM); Whitewater Canyon at 0.6 mi N I-10, 1470 ’, Apr 25, 2018 (RAJC); Banning, Apr 19, 1924 (LACM); 3 mi NW Desert Hot Springs, Apr 11, 1952 (LACM); Mule Mtns at Coon Hollow, 525’, Feb 1, 1967 (LACM); San Jacinto Creek, Apr 7, 1939 (LACM); Magnesia Canyon, Jul 20, 1952 (UCDC); Perris, no date & Jul 11, 1988 (UAIC; UCDC; USNM); Temecula (MWD land), 379 m, Jul 11, 1997 (UCDC); 12 mi S Thermal, Jul 21, 1967 (UCDC); Deep Canyon, Dec 4, 1967 & Apr 18–Jul 24, 1969 & Dec 7, 1970 & no date (UAIC); W rim Deep Canyon, 2000’ & 2500’, May 8, 1969 & May 7, 1979 (UAIC); Black Hill (T6S, R6E, Sect 19), 3000’, Mar 9, 1970 (UAIC); Chiriaco Summit, Apr 25, 1986 (UAIC); Dos Palmas Spring (T6S, R5E, Sect 26), Apr 29, 1969 (UAIC); 15.5 km NE Temecula, 470 m, May 3, 2016 (MMPC); 9 km S Desert Center, 690 m, Apr 17, 2014 (MLBC; MMPC); Salton Sea at Mecca Beach Campground, - 60 m, Apr 18, 2014 (MLBC); no loc, May 3, 1951 & no date (UAIC); no loc, Apr 4, 1942 (LACM). San Bernardino Co.: 50 km NNW Baker, Jan 12, 1981 (UCDC); Fenner, Mar 9, 1919 & Jun 18, 1931 (LACM; USNM); Hesperia, Nov 18, 1928 (USNM); Barstow, Apr 6, 1930 (USNM); Morongo Valley, Mar 29, 1952 (UCDC; USNM); Morongo Valley, Dry Morongo Canyon, Apr 7, 1963 & Jul 10, 1963 (LACM; UAIC); Soda Spring, May 8, 1991 & Feb 1992 (CIDA; LACM); Yermo, Apr 24, 1952 (LACM); Joshua Tree National Monument, 3000’, Apr 26, 1952 (LACM); Joshua Tree, 3000’, Apr 26, 1952 (LACM); Yucca Valley, Jun 29, 1934 (LACM); Hwy 372 at 4.5 mi NNE Landers turnoff, 3390’, Sep 30, 2018 (RAJC); Needles, May 1905 & Jul 8, 1931 (LACM; UAIC); 2 mi N Iron Mtn, Feb 6, 1984 (LACM); Kelso Sand Dunes, Mar 27, 1973 (LACM); Kelbacker Rd at 2 mi S Kelso, 2158’, Apr 18, 2000 (UCDC); Loma Linda, no date (UAIC); Hwy 247 at Barstow (near Mohave National Reserve Hdqrtrs), 2470’ Apr 25, 2018 (RAJC); Hwy 95 at 6.6 mi S Needles, 900’, May 3, 2018 (RAJC); no loc, no date (LACM; USNM). San Diego Co.: Pinyon Ridge, no date, 1931 (USNM); Culp Valley Rd at 0.5 mi W Hwy 22, 3080’, Apr 1, 1997 (RAJC); Culp Valley campground, 1015 m, Jan 1, 2014 (MLBC); Sentenac Canyon, 2400’, Apr 23, 1952 (LACM); Jacumba, May 30, 1940 (LACM); Moosa Canyon, Apr 20, 1892 (USNM); 16 km S Ocotillo Wells, 180 m, Feb 28, 1988 (UCDC); 14 km SSW Borrego Springs, 620 m, Feb 26, 1988 (UCDC); Anza Borrego State Park at Yaqui Well, Mar 22, 1978 (UAIC); Borrego Springs, 620’ & 195 m, Jul 31, 2003 & Dec 31, 2013 & Apr 25, 2018 (MLBC; RAJC); Lakeside, Dec 22, 1910 (UAIC). San Luis Opispo Co.: Carrizo, Mar 1939 (LACM). No county: Mohave Desert, Jul 1931 & no loc, no date (LACM; UAIC; USNM); Death Valley, Mar 4, 1941 (UCDC); Cala (= California), no date (LACM; USNM); Colorado Desert, Aug 11, 1917 (UAIC); Mohave Desert, Bar S Ranch, Nov 18, 1928 (USNM); Panamint Valley, Mar 24, 1930 (USNM). Nevada: Clark Co.: Mesquite, 1600’, Apr 2, 1970 (RAJC); Boulder City, 2500’, May 24, 1975 & Jun 27, 1977 & no date (LACM; UAIC); 4 mi SE Henderson, 2200’, Apr 20, 1971 (LACM); 2 mi SSE Riverside, 2200’, Apr 4, 1971 (LACM); 17 mi E Searchlight, Nov 24, 1969 (LACM); T26S, R65E, Nov 24, 1969 (LACM); Newberry Mtns, no date, 1954 (LACM). Esmeralda Co.: Hwy 72 (= Hwy 267?) at State Line, 4000’, Oct 31, 1967 (LACM). Nye Co.: Amargosa Desert near Beatty, Mar 8, 1931 (USNM); Amargosa River at 14 mi SSE Beatty, 2700’, Mar 26, 1972 (RAJC); 9 mi SSW Beatty, 3000’, Apr 15, 1970 (LACM); Devil’s Hole, 2600’, May 5, 1968 (LACM); Rock Valley near Mercury, Apr 21, 1971 (LACM); Lathrop Wells, 2300’, Apr 14, 1964 (LACM); Mercury, May 26, 1960 & Jul 1, 1961 (LACM; USNM); Ash Meadows, Mar 24, 1996 (UCDC). Locations that could not be geolocated. UNITED STATES: Arizona: Pima Co.: Catalina Mtns at South Fenner Canyon, 3000’, Mar 9, 1919 (UAIC). Questionable locales (outside of geographic range): UNITED STATES: Arizona: Santa Cruz Co.: Mt. Wrightson, 7000–8000’ Oct 22, 1960 (UAIC). California: Mariposa Co.: Big Tree, Jan 1940 (UCDC). Santa Clara Co.: Palo Alto, no date (USNM). Florida: Charlotte Co.: Punta Gordo, Feb 2, 1919 (USNM) (Figure 41A).
Etymology. The specific epithet, pergandei, was derived from the type series being obtained from Theodore Pergande, an early American entomologist of German descent.
Discussion. Veromessor pergandei is sympatric with the congeners V. andrei, V. julianus, and V. stoddardi. However, workers of V.pergandei are easily separated from these species based on: (1) well developed psammophore, (2) blunt toothlike projection on medial lobe of clypeus, (3) mostly concolorous dark brownish-black to black, and (4) lack of rugae on mesosoma and the cephalic dorsum posterior to eyes. In V. andrei and V. stoddardi: (1) psammophore poorly developed, (2) blunt toothlike projection lacking on medial lobe of clypeus, (3) coloration mostly orangish to reddish or reddish-brown (though V. andrei sometimes can be dark brownish-black to black), and (4) weak to coarse rugae on mesosoma and cephalic dorsum posterior to eyes. Veromessor pergandei is distinguished from V. julianus by: (1) propodeal spines short, length less than the distance between their bases, (2) dorsum of pronotum coriarious, lacking rugae, (3) mesopleura mostly coriarious, lacking rugae, (4) blunt toothlike projection on medial lobe of clypeus, and (5) in profile, eye narrowed below with a distinct ventral angle. In V. j ulianus: (1) propodeal spines long, length> 2.0× the distance between their bases, (2) dorsum of pronotum with irregular transverse rugae, (3) mesopleura with longitudinal rugae or lineogranulate, (4) blunt toothlike projection lacking on medial lobe of clypeus, and (5) in profile, eye rounded below. Veromessor pergandei is recognized in the field based on their large colonies (> 35,000 workers) of blackish to black workers that forage in long columns (Rissing, 1988; Tevis, 1958; Went, Wheeler, & Wheeler, 1972).
A molecular phylogeny that used UCEs shows V. pergandei is sister to the clade containing V. lariversi and V. pseudolariversi (M.L. Borowiec, unpub. data).
Biology. Veromessor pergandei is the best studied species in the genus. Nests are usually in sandy soils and consist of one entrance (occasionally more than one, especially during mating flights) with a circular gravel mound up to 50 cm in diameter; nests extend to a depth of 3–4 m or more with a distinctly angled shaft (Johnson, 1992; Tevis, 1958; Tschinkel, 2015; Wheeler & Creighton, 1934). Workers are weakly polymorphic (Gordon, 1978; Rissing, 1987).
Colonies contain tens of thousands of workers; Went et al. (1972) estimated> 35,000 workers in one foraging column, suggesting colonies contain several times that number of workers. Colonies forage most days of the year, but forager number decreases drastically during winter months. Foraging time varies seasonally according to temperature: colonies forage diurnally when days are cool, and they become crepuscular-matinal as temperatures increase. Colonies sometimes forage nocturnally when nights are warm (Snelling & George, 1979; Tevis, 1958; Went et al., 1972; Wheeler & Rissing, 1975b), but colonies appear to be strictly diurnal in eastern portions of their range (R.A. Johnson, pers. obs.).
Workers forage in a well-defined, pheromone-based column that is up to 40 m long, with workers fanning out to forage individually at the distal end of the column; colonies sometimes have two or three foraging columns (Plowes, Colella, et al., 2014; Ryti & Case, 1986; Went et al., 1972; Wheeler & Rissing, 1975b; Wheeler & Creighton, 1934). Pheromones are the primary mechanism for workers orienting in foraging columns, but workers also respond to sun position and experimental shifts in polarized light, and they display backtracking when displaced from foraging columns. Workers also use path integration in both the foraging column and in the fan (Freas, Congdon, Plowes, & Spetch, 2019, 2020; Freas, Plowes, & Spetch, 2019; Plowes et al., 2019; Plowes, Ramsch, Middendorf, & Hölldobler, 2014).
Foraging columns rotate around the nest such that colonies visit the entire area surrounding their nests, suggesting that columns function for both food acquisition and territorial interactions (Rissing, 1988). Scouts are not used to assess foraging column direction (Went et al., 1972; Wheeler & Rissing, 1975b), but rather direction of the daily foraging column is determined by chemicals secreted from the pygidial gland (see below and Hölldobler et al., 2013). In the laboratory, workers can detect recruitment pheromones of previous foraging columns for 7–10 days (B. Hölldobler, pers. comm.), suggesting a mechanism for colonies to adjust day to day direction of the foraging column. Secretions from the pygidial gland (primarily n-tridecane) appear to initiate the foraging column (Hölldobler et al., 2013), while a trail pheromone (primarily 1-phenylethanol) released from the poison gland maintains recruitment to the foraging fan (Plowes, Colella, et al., 2014). The recruitment effect from the poison gland is enhanced when adding pygidial gland secretions (Plowes, Colella, et al., 2014). Benzaldehyde was also a major compound in their pygidial gland secretions, but this chemical was not detected in mandibular gland secretions, as suggested by Blum, Padovani, Curley, and Hawk (1969). Like other large-colony congeners, workers of V. pergandei have a large pygidial gland reservoir with a textured tergal cuticle (Hölldobler et al., 2013).
Colonies of V. pergandei also assess and respond to natural seed density because day to day change in foraging column direction is higher in years with low compared to high seed density (Johnson, 1989). Similarly, when novel seeds are presented in an experimental patch, foragers sample fewer seeds before harvesting one in years with low seed density compared to years with high seed density (Johnson, 1991). However, foraging column length does not change with seed density (Rissing, 1988; Rissing & Wheeler, 1976). Fighting occurs between foraging columns that encounter one another, resulting in “black piles of dead ants” (Wheeler & Rissing, 1975b), but more often columns avoid foraging toward nearest neighbors (Ryti & Case, 1986, 1988a).
That workers of V. pergandei are weakly polymorphic has been used to test foraging efficiency based on the idea of “size matching” between worker body size and food item size. These studies show that the correlation of body size and seed size varies among colonies, and even when size correlations are significant, they often account for <5% of the variance (Davidson, 1978; Gordon, 1978; Rissing, 1981; Rissing & Pollock, 1984; Waser, 1998).
Worker size variation was also found to be inversely correlated with number of potentially competing seedharvester ant species over an approximately 650 km longitudinal cline (Davidson, 1978). This geographic pattern of size variation was suggested to be an adaptive response to the local competitive environment because colonies could exploit a broader range of seed resources (sizes) in locales with fewer competitors, while diets narrowed in areas with more competitors. Two lines of evidence lend doubt to this interpretation. First, the correlation between worker body size and food item size (i.e., size matching) varies among colonies, and even when correlations are significant, they often account for <5% of the variance (Davidson, 1978; Gordon, 1978; Rissing, 1981; Rissing & Pollock, 1984; Waser, 1998). Second, worker size and amount of worker size variation changed seasonally at two widespread locales (Gordon, 1978; Rissing & Pollock, 1984), and at both sites, amount of intracolony variation within a year was similar to the total amount of geographic variation found by Davidson (1978). This suggests that site differences noted by Davidson were related to variations in timing of the cycle rather than to the local competitive environment. Additionally, variation in timing of the body size cycle appeared to occur across sites in southern California, as observed during informal surveys during April–May 2018. These surveys indicated that colonies in low desert habitats contained small workers, while those in high desert habitats contained larger workers (R.A. Johnson, pers. obs.). In combination, these data indicate that seasonal variation in worker size is a speciesspecific trait in V. pergandei, but the underlying mechanism causing this variation is unknown.
Two additional studies have examined worker polymorphism in V. pergandei. One study examined nest architecture, finding that groups of polymorphic workers constructed nests that were longer with a more complex architecture than groups of single-sized workers (Kwapich, Valentini, & Hölldobler, 2018). The other study examined the interaction between predatory spiders (Steatoda spp. and Asagena spp.) and V. pergandei workers. Workers of V. pergandei become ensnared in the spider webs, and presence of an ensnared nestmate increased the probability of web removal and nestmate retrieval. Web removal was accomplished by larger-bodied workers (Kwapich & Hölldobler, 2019).
Foragers of V. pergandei learn several components related to handling and search efficiency of seeds (Johnson, 1991). In an experimental patch of novel seeds, workers initially handled then dropped multiple novel seeds before harvesting one, apparently to learn seed characters such as mass and shape. Number of seeds handled before one was harvested decreased over time, but workers still harvested heavier than average seeds because they handled but rejected lightweight seeds. Handling time per seed and trip time (travel time to and from the nest and time inside the nest) decreased for individuals within one foraging period. In terms of memory, tactile-associated behaviors, such as handling time per seed and number of seeds handled, were lost quickly compared to olfactory-associated behaviors such as seed recognition and acceptance (Johnson, 1991). Rate of learning to recognize a novel seed species was negatively associated with measures of seed species diversity (Johnson, Rissing, & Killeen, 1994). Workers also assess distance from the nest given that more seeds are handled before one is harvested when the experimental seed patch is farther from the nest while still harvesting seeds that are heavier than the average of those offered in the patch (Rissing & Pollock, 1984). That workers specialize on harvesting particular seed species may result from learning to identify and handle acceptable seeds (Rissing, 1981).
Alate production is influenced by intraspecific competition and precipitation. Food-supplemented and neighborremoved colonies produced more sexuals than control colonies (Ryti & Case, 1988a).Affect of food supplementation on production of sexuals was further examined in another field experiment in which food was supplemented early (when queens were laying reproductive eggs) or late (after queens presumably stopped laying reproductive destined eggs), along with a worker removal treatment and a control treatment. Early fed colonies produced more alates and a more strongly female-biased sex ratio than other treatments, while worker removal treatments produced the fewest alates and least female-biased sex ratios. Late fed colonies produced sexuals with the heaviest wet masses (males and females) and dry masses (only males) (Ode & Rissing, 2002). Number of sexuals produced and flight activity also decreased in very dry years (Cahan, 2001b).
Mating flights occur from mid-February through early April and usually occur over up to several weeks, with few sexuals released on a given day. Mating flights occur during mid-morning on sunny days with little wind (Creighton, 1953; Johnson, 2000a; Pollock & Rissing, 1985). Mating occurs in the air (S.W. Rissing, pers. comm; R.A. Johnson, pers. obs.).
Queens of V. pergandei mate with multiple males (Kwapich, Gadau, & Hölldobler, 2017; Ode & Rissing, 2002). Patriline number ranged from one to seven (mean = 3.80, n = 9 colonies) with an effective mating frequency (M e) of 2.56 (Kwapich et al., 2017). The most productive colonies had significantly fewer patrilines, a larger peak forager population, and a larger annual foraging range (Kwapich et al., 2017). Dry mass of alate queens averages 20.5 + 0.3 mg. Alate queens contain an average of 71.6 + 3.6 (n = 5) ovarioles, and mated queens contain an average of 2.90 + 0.17 (n = 4) million sperm. Dry mass for virgin males averages 5.7 + 0.2 mg, and they contain an average of 26.9 + 1.39 (n = 5) million sperm (R.A. Johnson, unpublished data). Queens of V. pergandei have a lower tolerance to high temperatures than do most other desert ants with most queens dying at 42 o C and all dying at 43 o C over 2 h (Johnson, 2000a).
Queen founding behavior varies across the geographic range: single queens (haplometrosis) initiate nests in western portions of the range, that is, southwestern Arizona and southern California, whereas multiple, unrelated queens (pleometrosis) initiate nests in eastern and northwestern portions of the range, that is central and western Arizona, southeastern California, and southern Nevada (Hagen, Smith, & Rissing, 1988; Helms Cahan & Helms, 2012; Johnson, 2000a; Pollock & Rissing, 1985; Rissing, Johnson, & Martin, 2000; Ryti, 1988). Pleometrotic queens cooperate to produce the first brood of workers, with worker production being a linear function of queen number (Rissing & Pollock, 1986, 1991). Additional variation occurs in pleometrotic parts of the range because colonies reduce to one queen in eastern areas, whereas multiple queens persist in mature colonies (primary polygyny) in northwestern portions of the range (Helms & Helms Cahan, 2012; Rissing & Pollock, 1986; 1987). Worker aggression and elimination of queens were correlated with region of origin. In areas of queen reduction, queens were as likely to be killed by workers as by other queens (Helms, Newman, & Helms Cahan, 2013). In southeastern California, the shift from haplometrosis to pleometrosis occurs across a narrow transition zone with the shift to pleometrosis correlating with reduced precipitation, decreased vegetative biomass, and lower colony density (Cahan, 2001a, 2001b; Cahan, Helms, & Rissing, 1998). Queen mass varies across the three reproductive strategies: queens in haplometrotic areas are heaviest, those in areas of pleometrosis with queen reduction (secondary monogyny) are intermediate in mass, and those in areas of primary polygyny are lightest (Helms Cahan & Helms, 2014). Variation in these queen founding strategies correlated with brain monoamine content. Serotonin levels were significantly higher in life stages where queens displayed aggression, suggesting the serotonin modulates aggression in queens of V. pergandei (Muscedere et al., 2016). Regions with alternate queen social forms currently meet in contact zones where gene flow and selection on alternate social forms should occur. Two types of genetic data infer that these three reproductive strategies/zones represent intraspecific behavioral variation rather than the existence of cryptic species. Microsatellite data indicated significant genetic differentiation across the sites, but diffentiation across the three reproductive zones did not correspond to the spatial pattern of genetic structure among sites (Helms & Helms Cahan, 2012). A molecular phylogeny based on UCEs gave similar results, showing that colonies in the three reproductive zones did not segregate into separate clades (M.L. Borowiec, unpub. data).
Pleometrotic colony founding has been studied in eastern portions of their geographic range (southcentral Arizona). These pleometrotic queens are unrelated, they coexist without dominance, and they appear to actively prefer associations because single queens more readily abandon nests to join associations than do queens already in groups (Hagen et al., 1988; Helms Cahan & Helms, 2012; Krebs & Rissing, 1991; Rissing & Pollock, 1986). All queens lay a similar number of eggs, and the first workers emerge earlier and more workers are produced (number is a linear function of queen number) by pleometrotic compared to haplometrotic queens (Rissing & Pollock, 1991). After the first workers emerge, queens become aggressive, and colonies reduce to one queen. Laboratory colonies brood raid adjacent colonies and those with pleometrotic queens are more successful than haplometrotic colonies (Rissing & Pollock, 1987). This advantage resulted from the additional workers produced by pleometrotic queens because brood raiding success increased for haplometrotic colonies that were worker-supplemented (Rissing & Pollock, 1991). Brood raiding between incipient colonies and mature colonies killing incipient colonies also occurs in the field (Pfennig, 1995; Raczkowski, 2003; R.A. Johnson, pers. obs.). Field experiments to test the benefits of pleometrosis have had variable results. In one study, experimental haplometrotic and pleometrotic colonies survived to the first worker stage at a similar rate and had a similar longevity (Pfennig, 1995), while pleometrotic colonies emerged at a higher rate and outlived haplometrotic colonies in another study at the same site (Raczkowski, 2003). Surviving colonies then enter their growth phase and probably start producing reproductive sexuals after 3–4 years; colonies likely live 10–20+ years (Tevis, 1958; Wheeler & Rissing, 1975a).
Rainfall is critical for recruitment of V. pergandei colonies in central Arizona where queens found nests cooperatively. In a laboratory experiment, survival, condition, and brood condition increased with water level for single queens. In a two-way experiment with queen number and water level as main effects, queen survival was positively influenced by both water level and queen number. Water level also was a significant effect for three measures of queen condition in the latter experiment, but queen number was not significant for any of these measures, suggesting that enhanced worker production is the primary advantage of pleometrosis. A discriminant analysis using recruitment and rainfall data over 20 years for a site in central Arizona, USA, documented that recruitment occurred only in years in which rainfall for both January–March and April–June (the critical period for nest founding and survival of incipient nests) exceeded the long-term mean amount of rainfall. This discriminant analysis also predicted that no recruitment occurred when long-term mean rainfall for January– March and April–June at the site were included as ungrouped periods. This suggests that pleometrosis in V. pergandei evolved to enhance colony survival in areas with harsh abiotic (desiccating) conditions, facilitating colonization of habitats in which solitary queens could not establish even in wet years (Johnson, 2021).
Mature colonies of V. pergandei are overdispersed (Ryti & Case, 1984, 1986), but foundress queens have a clumped dispersion (Pfennig, 1995; Ryti & Case, 1988b). In one study, new foundress nests were usually associated with mature colonies (Pfennig, 1995), while new foundress nests were farther than expected from mature conspecific nests in another study (Ryti & Case, 1988b). Moreover, foundress queens prefer to initiate nests in open, exposed sites (Rissing & Pollock, 1989; R.A. Johnson, pers. obs.), such that these queens more likely choose microsites per se rather than locations based on presence or absence of mature colonies. Ryti and Case (1988b) continued monitoring these foundress nests finding that they were randomly dispersed after three months (when the first minims emerged) due to mortality caused by such as raids by adjacent foundress nests and mature colonies (see above).
Colonies of V. pergandei relocate their nest up to 10 times per year, with the surface extent of active and abandoned nests extending 10–15 m in diameter (Tevis, 1958). Nothing is known about causes of nest relocation in V. pergandei.
Veromessor pergandei also affect the distribution and abundance of plants. Nest mounds/refuse piles of V. pergandei colonies contained more plant species than adjacent control plots, and plants on mounds/refuse piles produced more, and sometimes heavier, seeds than plants in adjacent control plots (Rissing, 1986).
Desert ants such as V. pergandei experience major physiological challenges because their small size and high surface to volume ratio make them prone to desiccation. One adaptation to minimize water loss is that workers have low water loss rates that are comparable to those of other desert arthropods (Johnson, 2000c; Lighton, Quinlan, & Feener, 1994). Nevertheless, workers lose a significant amount of water during a foraging period (Feener & Lighton, 1991; Lighton et al., 1994). This water is presumably regained before the next foraging period, but the source of this water is unknown (Feener & Lighton, 1991; Johnson, 2000c; Johnson, Kaiser, Quinlan, & Sharp, 2011). Cuticular abrasion caused by digging increases water loss rate in both workers and queens, and this damage is partially repaired over time in queens (Johnson, 2000c; Johnson et al., 2011). Moreover, V. pergandei appears to survive in hot, xeric environs because of avoidance rather than tolerance to heat and desiccation. Ventilation patterns and metabolic rate of workers and alate queens are discussed in Lighton and Berrigan (1995).
Several genera of spiders (Asagena, Euryopsis, Steatoda) (Hale et al., 2018; Kwapich & Hölldobler, 2019) and horned lizards (Phrynosoma spp.) prey on workers of V. pergandei (R.A. Johnson, pers. obs.).
Veromessor pergandei inhabits the Sonoran, Colorado, and Mohave Deserts, in areas that collectively encompass the hottest, most arid portions of North America; colonies occur in sandy soil at elevations from - 80–1,400 m (Creighton, 1950, 1953; Johnson, 1992, 2000b; Tevis, 1958; Wheeler & Wheeler, 1973). This species occurs in the Mohave desert, Sonoran desert, Baja California desert, Gulf of California xeric scrub, and California coastal sage and chaparral ecoregions, as defined by Olson et al. (2001) (Figure 41A).
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 67-80, DOI: 10.11646/zootaxa.5206.1.1, http://zenodo.org/record/7318829