In his original description Forel (1893) compares it to B. heeri, noting the B. minutus has longer scapes than B. heeri, and is generally more slender, small and pale. Forel also discussed the biology of the species, writing that it was rather rare, lived in colonies of up to 150 individuals, excavated nests with wide tunnels and small chambers amongst the roots of sod. Brachymyrmex minutus is introduced in Florida, where it nests in the leaf litter (Deyrup et al., 2000b). It was first reported there in 1994 (Ferster & Prusak, 1994), but specimens have been identified from 1984 (Deyrup et al., 2000b). Very little else is known about the biology of the species.
Costa Rica: This species occurs in wet and moist forest habitats on both slopes. On the Atlantic slope it occurs in the lowlands and as high as 800m in the Peñas Blancas Valley. It does not occur in the Monteverde cloud forest but appears again in the moist forest habitats on the Pacific slope just below Monteverde. It occurs in lowland and montane rainforest, and also in urban and agricultural areas in the Central Valley. For example, I have collected workers in a small patio area of a San José hotel.
The species appears to nest and forage near ground level. The nests I have observed have been under stones, and one was in the base of a live fern. At La Selva Biological Station, workers have been collected in Winkler samples of sifted leaf litter and in Malaise traps, but in only one of 51 Project ALAS fogging samples. Workers may be collected at baits on the ground or as foragers on low vegetation.
Prior to Jan 2019, Longino identified this species as JTL007.
Diagnosis among workers of introduced and commonly intercepted species. Antenna 9-segmented. Antennal club indistinct. Antennal scapes surpassing the posterior margin of head by more than 1/5th their length. Eyes of moderate size (greater than 5 facets). Head with or without distinct ocelli. Antennal sockets and posterior clypeal margin separated by a distance less than the minimum width of antennal scape. Dorsum of mesosoma lacking a deep and broad concavity. Metanotal groove present. Pronotum and mesonotum with pairs of erect hairs. Propodeum and petiolar node both lacking a pair of short teeth. Propodeum lacking posteriorly projecting protrusion. Metapleuron with a distinct gland orifice. Waist 1-segmented (may be hidden by gaster). Petiolar node appearing flattened. Gaster armed with acidopore. Gaster (especially first segment) with dense pilosity, giving it a dull appearance. Color yellow.
Brachymyrmex minutus can be distinguished from most other introduced members of the genus by the following combination of characters: (1) dense pubescence on the first gastral tergite, (2) antennal scapes exceeding posterior margin of head by at least 1/5 their length, (3) erect hairs on the pronotum and mesonotum, and (4) pale yellow in color.
[[ worker ]]. L. 1,0 a 1, 3 mill. Mandibules armees de 5 dents. Tete ovale-rectangulaire, plus longue que large, plus etroite et a cotes plus convexes que chez le B. Heeri. Yeux situes au tiers anterieur des cotes de la tete (plus en arriere chez le B. Heeri). Ocelles parfois visibles. Les scapes depassent considerablement le bord posterieur de la tete (bien plus que chez le Heeri). Epistome comme chez le B. Heeri. Aire frontale tres-petite et assez profonde. Tout le corps plus grele, plus etroit que chez le B. Heeri. Le thorax est distinctement, quoique faiblement echancre entre le mesonotum et le metanotum. Il est moins deprime et plus etroit que chez le' Heeri. Les stigmates mesothoraciques sont moins apparents et situes non pas, comme chez le B. Heeri, sur la face dorsale, mais un peu plus sur la face laterale du thorax, derriere l'echancrure. Ecaille petite, basse, inclinee en avant.
Luisant, tres superficiellement et tres finement chagrine; epi- stome lisse. Ca et la quelques poils dresses, surtout sur l'abdomen et le devant de la tete (bien moins que chez le B. Heeri). Pubescence adjacente jaunatre, espacee, ne formant nulle part duvet; elle est un peu plus abondante sur les pattes et sur les scapes qui n'ont pas de pilosite dressee.
D'un jaune pale; parfois d'un jaune un peu rougeatre (les exemplaires de St. Thomas). Les funicules, sauf le 1 er et le dernier article, le devant de la tete et parfois le milieu des tibias legerement brunatres.
[[ queen ]]. L. 2, 3 a 2, 7 mill. Caracteres de l'ouvriere. Beaucoup plus etroite que chez le B. Heeri. Les ocelles sont places suc trois taches d'un brun fonce. Pubescence plus forte que chez l'ouvriere, mais bien plus faible que chez la B. Heeri. Sut l' abdomen elle forme un leger duvet. Couleur de l'ouvriere, mais le dessus de l'abdomen legerement bruni, Ailes faiblement teintes do brunatre.
Antille de St. Vincent et Antille de St. Thomas, ou je l'ai recoltee moi-meme. Je l'avais alors confondue avec le B. Heeri (Mittheil. des Muenchener Entom .. Ver., 1881).
Cette espece ressemble tout d'abord aux petites [[ worker ]] du B. Heeri, mais lorsqu'on l'examine de pres, on la distingue facilement. a sa taille plus petite et plus grele, a son eclat plus grand, a sa pubescence plus faible, a la forme de sa tete, a l'echancrure du thorax et a la position des yeux. La [[ queen ]] du B. Heeri est beaucoup plus grande (plus de 4 mill.), ce qui reud une confusion impossible.
(47). Rather rare. Communities of fifty to one hundred individuals are found in large tunnels, with very small chambers at intervals, at the roots of sod. The workers are rather sluggish, but the female is pretty active. Only one gravid female is found in a nest.
(47 a). Petit Bordelle Valley, 1200 ft. Under sod on a stone, bank of stream; shady place. Nov. 12 th.
(47 b). Same date and locality as (47 a). Another nest; under sod on a rock.
(47 c). Same date and locality as (47 a). A single female found, without workers, at the roots of grass on a rock.
(47 d). Specimens referred to this species. Morne a
Garou, forest, 2000 ft. Nov. 1 st. Beaten from foliage.
(47 e). Upper Richmond Valley, 1500 ft. Nov. 27 th.
Thick forest by stream. A small nest at the roots of
plants, & c, growing on a rock.
(47 f). Same locality as (47 e). Obtained by beating branches in the forest.
Brachymyrmex minutus is a species of ant in the family Formicidae.[1][2][3][4]
Brachymyrmex minutus is a species of ant in the family Formicidae.
