Pheidole morrisii

U.S. They are found north to the state of New York , east to the states of Illinois , Missouri and Oklahoma , south to the states of Texas and Florida ^[1] .

Small earthen myrmycin ants with a dimorphic caste of workers, length about 3 mm: workers from 2.5 to 2.8 mm (average weight 0.12 mg), soldiers from 3.2 to 3.8 mm (average weight 0.47 mg ) They have numerous semi-spaced hairs on the head, breast, stalk and abdomen. The head of large workers ( soldiers ) is heart-shaped with a recess in the back of the head, mostly smooth, only in front on the cheeks covered with several linear wrinkles, lasting only to the line of the eyes. The head of the workers is rounded behind, without a notch. The antennae of workers and females are 12-segmented (males consist of 13 segments). The scape of the antennae of the soldier does not reach the occipital margin of the head by about two of its width. The scape of workers is relatively longer, about a third of its length exceeds the posterior edge of the head. Propodeal spines of the posterior thorax very short, serrated. The stalk between the breast and the abdomen consists of two segments: the petiolus and postpetiolus (the latter is clearly separated from the abdomen). The color of the soldiers is one-color yellow, small workers are also yellow, but with a darker head and chest. Large workers (soldiers): head width 1.26 mm, head length 1.26 mm, scape length 0.88 mm. Small workers: head width - 0.60 mm, head length 0.82 mm, scape length 0.90 mm ^{[1] [2]} .

P. morrisi nests in the ground. Families with one uterus , monogynous. New colonies are founded by single females, digging an underground chamber at a depth of 20 to 30 cm. The first workers appear after 30 days, and the first soldiers after about 50 days. After 8 months, the size of the colony reaches several hundred working ants and soldiers. Workers feed and collect food alone; soldiers can help transport food to the nest. Soldiers make up 11% in numbers and 30% in biomass of the total family. With the growth of the colony, this percentage of soldiers almost does not change, but it changes seasonally (27% in spring and 38% in summer). Foraging may occur at a distance of more than 8 m from the nest. Working ants, mainly harvesting dead arthropods, also predate and collect seeds. The size of adult colonies varies from 800 to 49,000 ants. The bulk of the nesting chambers (with a total volume of up to 3 liters) and ants are in the near-surface layer, but up to five vertical shafts go to a great depth, down to groundwater (1.5 - 2.0 m). The family begins to grow winged females and males with more than 3,000 working individuals. The temperature in anthills varies from 12 to 17 degrees in winter and from 23 to 33 ° C in summer ^{[3] [4] [5]} . Due to the high number of colonies, it plays an important ecological role in pine (with the predominance of such a tree as bog pine , Pinus palustris ) and coastal savannah ecosystems in the eastern and southern United States ^[6] .

The taxon was first described in 1886 by the Swiss worldmecologist Auguste-Forel ( Auguste-Henri Forel ; 1848-1931) ^[7] , and its valid species status was confirmed during a generic audit conducted in 2003 by the American worldmecologist Professor Edward Wilson . It is similar to the species of the Pheidole fallax -group, differing in head sculpture and pubescence. The species was named after M. Morrisi (M. Morrisi), who collected a type series in the United States in the XIX century ^{[1] [8]} .

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  Soldier in profile

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  Soldier on top

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  Worker's head

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  Worker on top

• Wilson EO Pheidole in the New World. A dominant, hyperdiverse ant genus . - Cambridge, MA .: Harvard University Press , 2003 .-- S. 325. - P. 794. - ISBN 0-674-00293-8 .
• Feener, DH, Jr. Response of Pheidole morrisi to two species of enemy ants, and a general model of defense behavior in Pheidole ( J. ) // J. Kans. Entomol. Soc. : Journal. - 1987. - Vol. 60. - P. 569-575 .

Pheidole morrisii (neopr.) . Encyclopedia of Life. Date of treatment January 31, 2016.