Temnothorax longispinosus

(Roger, 1863)

Long-spined Acorn Ant

Temnothorax longispinosus is a small North , measuring 2–2.5 mm in length, commonly known as the Long-spined Acorn Ant. It inhabits forest environments and nests primarily in preformed cavities within leaf litter, including hollow nuts and acorns. The species exhibits remarkable with three distinct associated with alternative nest-founding strategies: small queens with reduced capacity that practice dependent colony founding by returning to natal nests; large queens with low fat reserves that found colonies via pleometrosis (cooperative founding with multiple queens); and large queens with high fat reserves that practice haplometrosis (solitary founding). This species serves as a for the slave-making ant Protomognathus americanus and has been extensively studied for its genomic to climate variation and pressure.

Temnothorax longispinosus by (c) April Nobile, some rights reserved (CC BY). Used under a CC-BY license.

Casent0914508 p 1 high by Dominique Monie. Used under a CC BY 4.0 license.

Temnothorax longispinosus casent0104819 dorsal 1 by April Nobile. Used under a CC BY 4.0 license.

Pronunciation

How to pronounce Temnothorax longispinosus: //ˌtɛmnoʊˈθɔːræks ˌlɔːŋɡɪˈspaɪnoʊsəs//

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

Distinguished from similar Temnothorax by its small size (2–2.5 mm) and the presence of small protrusions towards the and . provides a diagnostic feature: three distinct queen occur within , differing in body size, length, and fat content. Small queens (short wings, very low fat) are produced in lower numbers than large morphs and are more frequently associated with polygynous nests. The species can be differentiated from its Temnothorax curvispinosus, with which it has been studied in competition experiments, through morphological examination and geographic distribution patterns. Molecular identification may be necessary for definitive separation from cryptic species within the .

Images

Appearance

Small measuring 2–2.5 mm in body length. The exhibits characteristic small protrusions extending from the body towards the and , a trait common in the Temnothorax. display distinct morphological : small queens possess short and very low fat reserves; large queens have long to very long wings with variable fat content (low or high). are and typical of the genus in general body plan.

Habitat

Forest , particularly deciduous and mixed forests. Nests occur in preformed structures within the leaf litter layer, especially hollow nuts (particularly acorns) and small twigs. Nesting habits vary seasonally but consistently utilize existing cavities rather than excavating new nest spaces. The occupies the forest floor microhabitat, with nests typically located in accumulated leaf litter and woody debris.

Distribution

Eastern United States, eastern Canada, and British Columbia. Specific studies have been conducted in southern Wisconsin and the northeastern United States. The occurs across a broad latitudinal range encompassing temperate forest of North America.

Host Associations

Protomognathus americanus - for this slave-making ; subject to raiding and theft

Life Cycle

Colony founding occurs through three alternative strategies associated with : (1) dependent founding by small queens with short and very low fat content, which return to natal nests at higher rates; (2) independent founding via pleometrosis (multiple queens cooperating) by large queens with low fat and long wings; (3) independent founding via haplometrosis (single queen) by large queens with high fat and very long wings. Small queens are produced in lower numbers than large morphs and are more common in polygynous colonies. Despite morphological specializations suggesting fixed strategies, queens exhibit extensive behavioral flexibility in founding .

Behavior

Exhibits with alternative colony-founding behaviors. Small queens show significantly reduced activity compared to large queens, which may facilitate returning to the natal nest after mating when swarms occur nearby. Both queen mate exclusively in male swarms without female calling . demonstrate larval recognition capabilities that ensure preference over heterospecific , with colony-level chemical referents governing discrimination. When the queen is removed or dies, some brood-care workers can develop and begin (worker ).

Human Relevance

Research model organism for studies of evolution, , and genomic . Has been used in studies of with Temnothorax curvispinosus. Subject of investigation regarding phenological shifts and responses to climatic factors in prairie and forest . The ' association with acorn nesting makes it relevant for studies of forest floor dynamics and cavity-nesting .

Similar Taxa

Temnothorax curvispinosusCo-occurs in eastern North America and has been studied in direct competition experiments; both are small acorn-nesting but differ in morphological details and geographic distribution patterns
Temnothorax ambiguus of Protomognathus americanus; shares similar and but differs in larval recognition cues and geographic range

More Details

Genomic adaptations

genomic studies have identified candidate SNPs associated with , particularly in odorant receptor genes involved in sensory perception of smell. Cuticular hydrocarbon composition varies with climate (n-alkanes) and shows trends with parasite prevalence. Antennal correlates strongly with local parasite prevalence, indicating rapid evolutionary responses to coevolutionary pressure from .

Queen morph flexibility

Despite morphological specializations resembling with fixed , the three of T. longispinosus show extensive behavioral overlap and flexibility, potentially representing early evolutionary stages of more specialized dispersal systems seen in other .