''Novomessor cockerelli'' is a species of

ant Ants are eusocial insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from vespoid wasp ancestors in the Cretaceous period. More than 13,800 of an estimated total of ...

in the subfamily Myrmicinae. It is native to the deserts of the Southwestern United States and Mexico. It lives in large underground

colonies In modern parlance, a colony is a territory subject to a form of foreign rule. Though dominated by the foreign colonizers, colonies remain separate from the administration of the original country of the colonizers, the '' metropolitan state'' ...

in which there is a single queen. The worker ants leave the nest daily to forage for seeds, plant material and dead insects.

Description

Aphaenogaster cockerelli castype00622 head 1

''Novomessor cockerelli'' is a large brown ant with a blackish gaster, long legs and an elongated head. It can be recognised by the two distinctive spines on the

propodeum The propodeum or propodium is the first abdominal segment in Apocrita Hymenoptera (wasps, bees and ants). It is fused with the thorax to form the mesosoma. It is a single large sclerite A sclerite (Greek , ', meaning " hard") is a hardened bod ...

. It can be distinguished from the rather similar '' Novomessor albisetosus'' by the shape of its head. It cannot sting but is very aggressive and has a powerful bite.

Distribution and habitat

''Novomessor cockerelli'' is found in arid areas of the Southwestern United States including Texas and the Franklin Mountains, New Mexico, Arizona, Nevada and California. It is also present in northern Mexico in the states of Sonora, Chihuahua, Durango, Coahuila and Nuevo León. Its typical habitat is upland plains includes desert areas with

ocotillo ''Fouquieria splendens'' (commonly known as ocotillo (), but also referred to as buggywhip, coachwhip, candlewood, slimwood, desert coral, Jacob's staff, Jacob cactus, and vine cactus) is a plant indigenous to the Sonoran Desert and Chihuahuan ...

(''Fouquieria splendens''),

cactus A cactus (, or less commonly, cactus) is a member of the plant family Cactaceae, a family comprising about 127 genera with some 1750 known species of the order Caryophyllales. The word ''cactus'' derives, through Latin, from the Ancient Gree ...

creosote bush ''Larrea tridentata'', called creosote bush and greasewood as a plant, chaparral as a medicinal herb, and ''gobernadora'' (Spanish for "governess") in Mexico, due to its ability to secure more water by inhibiting the growth of nearby plants. In S ...

mesquite Mesquite is a common name for several plants in the genus '' Prosopis'', which contains over 40 species of small leguminous trees. They are native to dry areas in the Americas. They have extremely long roots to seek water from very far under gr ...

sagebrush Sagebrush is the common name of several woody and herbaceous species of plants in the genus '' Artemisia''. The best known sagebrush is the shrub '' Artemisia tridentata''. Sagebrushes are native to the North American west. Following is an al ...

and thorn scrub at altitudes of between above sea level.

Behavior

''Novomessor cockerelli'' forms large underground colonies, sometimes with multiple entrances, on open ground or beside rocks. The nest tends to be surrounded by a midden, a circle of tiny pebbles and plant remains. The worker ants normally leave the nest to

forage Forage is a plant material (mainly plant leaves and stems) eaten by grazing livestock. Historically, the term ''forage'' has meant only plants eaten by the animals directly as pasture, crop residue, or immature cereal crops, but it is also used ...

in the early morning and in the evening, at which times the ground temperature is within the range . During the winter they may forage throughout the day. Seeds and plant material are collected but nearly half of the diet consists of the corpses of insects. These ants scavenge around carcases for dead insects such as flies. When a prey item is found that is too large for a single ant to carry, other ants are recruited by the use of

pheromone A pheromone () is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting like hormones outside the body of the secreting individual, to affect the behavio ...

s. The original ant liberates a glandular secretion which attracts other workers within about two metres (yards) of the release point. If this fails to summon enough assistance, it releases a further secretion on the ground and lays a trail back to the colony. Other ants are attracted to follow the trail and then work co-operatively to transport the food item back to the nest. The trail is short-lived and soon evaporates. In the

Chihuahuan Desert The Chihuahuan Desert ( es, Desierto de Chihuahua, ) is a desert ecoregion designation covering parts of northern Mexico and the southwestern United States. It occupies much of far West Texas, the middle to lower Rio Grande Valley and the lo ...

, ''Novomessor cockerelli'' competes for resources with another seed-eating ant species, the

red harvester ant ''Pogonomyrmex barbatus'' is a species of harvester ant from the genus ''Pogonomyrmex''. Its common names include red ant and red harvester ant. These large (5– to 7-mm) ants prefer arid chaparral habitats and are native to the Southwestern ...

(''Pogonomyrmex barbatus''). It has been found that workers of ''N. cockerelli'' will emerge from the nest early in the morning and plug the entrance holes of nearby ''P. barbatus'' colonies with grit and small stones thus delaying the emergence of the other workers. Nests close to the ''A. cockerelli'' home nest are plugged more often than ones far away, and older, larger nests have their entrances plugged more often than younger, smaller ones. In the Chihuahuan Desert, nuptial flights of ''Novomessor cockerelli'' occur in July at dusk. After returning to the ground, newly mated females soon remove their wings. They are not permitted by workers to enter established nests, but must find a new colony on their own. Each colony contains a single queen. She uses bodily secretions to prevent other colony members from laying viable eggs. The workers spend little time licking or grooming the queen and it is unclear exactly how her control of the colony comes about. It may be related to the coating of the eggs she lays, because the workers which care for them do lick them. The queen has a gland called the Dufour’s gland which secretes a chemical that she uses to mark any reproductive workers that may be present in the nest. This causes other worker ants to attack the marked ants and helps her maintain her dominant position. In an established colony, workers do not regurgitate food to give to the queen but instead lay

trophic egg A trophic egg, in most species that produce them, usually is an unfertilised egg because its function is not reproduction but nutrition; in essence it serves as food for offspring hatched from viable eggs. The production of trophic eggs has been ob ...

s for her to eat, and these eggs are also fed to the queen larvae. Workers seem to have alternating periods when they either go out to forage or they stay in the nest and tend the brood, at which time they are capable of producing trophic eggs. In a colony that has been deprived of its queen, some of the workers begin to lay and tend viable eggs after a few weeks, and these all develop into males. The colony ceases to exist when the males have emerged and all the workers have come to the end of their lives.

References

External links

* {{Taxonbar, from=Q13383329 Myrmicinae Insects described in 1893 Hymenoptera of North America