Cyphomyrmex minutus

A tropical species, or more likely a complex of closely related species (rimosus group), that can be locally abundant.

Identification
See the nomenclature section under Cyphomyrmex rimosus

Identification Keys including this Taxon

 * Key to US Cyphomyrmex workers

Distribution
This is a common species through the West Indies and around the Caribbean and Gulf of Mexico into Texas (Snelling and Longino 1992). It adapts well to disturbed sites and readily colonizes potted plants, so there is a high probability that it was brought to Florida at least once, but it might also be native to the state, having flown from the Bahamas or moved around the Gulf of Mexico. It was recorded from Florida in Smith 1930. (Deyrup, Davis & Cover, 2000.)

Distribution based on Regional Taxon Lists
Nearctic Region: United States. Neotropical Region: Bahamas, Barbados, Colombia, Costa Rica, Cuba, Dominican Republic, French Guiana, Greater Antilles, Guyana, Haiti, Honduras, Jamaica, Lesser Antilles, Mexico, Panama, Paraguay, Puerto Rico, Saint Lucia, Suriname, Trinidad and Tobago, Venezuela.



Biology
Longino (2004) provides a good account about the biology of species within this group that, in modified form, fits well with C. minutus: In much of the Neotropics these are among the most abundant attines in the habitat, but they are always inconspicuous ants. They have small colonies, with worker numbers usually in the tens to hundreds. The nests are usually in small chambers in the ground, under objects, or in rotten wood.

The main fungal substrates used by the common Cyphomyrmex are caterpillar droppings and dead insect parts. The insect parts are mainly heavily sclerotized bits of exoskeleton, and brightly colored beetle elytra seem to be particularly favored. When a small Cyphmyrmex colony is exposed by turning over a leaf on the forest floor or breaking into a small cavity in a rotten log, one is faced with an almost magical little scene: one or two large caterpillar pellets form the center of the fungus garden, embedded in a glittering, multicolored pile of beetle elytra, membracid pronota, and miscellaneous leg parts, and all covered with the little green fungal dots. The workers tuck their legs and become motionless on disturbance, entering a "cateleptic" state, and so at first the small brown workers are an invisible part of the background in and around the fungus garden. After a few minutes, if left undisturbed, one by one the workers appear to suddenly spring into motion.

Wheeler (1905), Bahamas - numerous workers from several nests collected near Nassau, N. P., (Fort Charlotte, Menendez Sisal Plantation, and Blue Hills), ...The nests were under stones, where the ants were guarding their fungus gardens on caterpillar excrement. The fungus consisted of small translucent, pear-shaped, yellow bodies, about .5 mm. in diameter. They were of exactly the same size and appearance as those which I first saw in the fungus gardens of the subsp. dentatus Forel in Mexico. More recently I have found these gardens and fungi in the nests of a dark variety of rimosus at New Braunfels, Texas, and in the nests of another variety on Key Largo, Florida.

Nomenclature

 *  minutus. Cyphomyrmex minutus Mayr, 1862: 691 (w.) CUBA. Mayr, 1887: 558 (q.m.). Junior synonym of rimosus: Dalla Torre, 1893: 150; Forel, 1895b: 137. Revived from synonymy as subspecies of rimosus: Emery, 1894c: 225; Wheeler, W.M. 1905b: 106. Subspecies of rimosus: Emery, 1924d: 342; Creighton, 1950a: 316; Kempf, 1966: 162. Revived status as species: Snelling, R.R. & Longino, 1992: 490. Senior synonym of steinheili: Mayr, 1887: 558; of comalensis: Creighton, 1950a: 315; of arnoldi, atrata, breviscapus, flavescens, venezuelensis: Snelling, R.R. & Longino, 1992: 490.
 * steinheili. Cyphomyrmex steinheili Forel, 1885a: 368 (w.) MEXICO. Junior synonym of minutus: Mayr, 1887: 558.
 * comalensis. Cyphomyrmex rimosus var. comalensis Wheeler, W.M. 1907c: 719, pl. 49, fig. 1 (w.q.m.) U.S.A. Junior synonym of minutus: Creighton, 1950a: 315.
 * atrata. Atta (Cyphomyrmex) rimosa r. atrata Forel, 1912e: 188 (w.q.m.) COLOMBIA. Combination in Cyphomyrmex: Emery, 1924d: 342. Junior synonym of minutus: Snelling, R.R. & Longino, 1992: 490.
 * arnoldi. Cyphomyrmex rimosus var. arnoldi Aguayo, 1932: 223 (w.) JAMAICA. Junior synonym of minutus: Snelling, R.R. & Longino, 1992: 490.
 * venezuelensis. Cyphomyrmex rimosus subsp. venezuelensis Weber, 1938b: 188 (w.) VENEZUELA. Junior synonym of transversus: Weber, 1958d: 261. Revived from synonymy as subspecies of rimosus: Kempf, 1966: 162. Junior synonym of minutus: Snelling, R.R. & Longino, 1992: 490.
 * breviscapus. Cyphomyrmex rimosus subsp. breviscapus Weber, 1940a: 412 (diagnosis in key) (w.) PANAMA. Junior synonym of minutus: Snelling, R.R. & Longino, 1992: 490.
 * flavescens. Cyphomyrmex rimosus subsp. flavescens Weber, 1940a: 411 (in key and footnote) (w.) HAITI. [First available use of Cyphomyrmex rimosus subp. minutus var. flavidus Wheeler, W.M. 1936b: 204; unavailable name.] Junior synonym of minutus: Snelling, R.R. & Longino, 1992: 490.

Worker
2.5 mm. Kahl, Kopf und Hinterleib dunkel rothbraun. Thorax und Stielchen braunlich-roth, Mandibeln, Fiihlel' und Beine roth. Kopf, Thorax und Stielchen ziemlich fein, abel' unregelmassig gerunzelt, hie und da mit kleinen Erhabenheiten; Hinterleib ebenfalls fein gerunzelt und zerstreut grob gekornt. Beine und Mandibeln glanzend, del'iibrige Korper matt.

Type Material
Aus Cuba erhielt ich ein Stuck diesel' sehr merkwurdigen Ameise' von Herm Riehl.