Lachnomyrmex longinoi

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Lachnomyrmex longinoi
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Attini
Genus: Lachnomyrmex
Species: L. longinoi
Binomial name
Lachnomyrmex longinoi
Feitosa & Brandão, 2008

Lachnomyrmex longinoi casent0178858 profile 1.jpg

Lachnomyrmex longinoi casent0178858 dorsal 1.jpg

Specimen labels

This ant has most commonly been found in leaf litter samples from wet forests (100–1200m) of Costa Rica and Panama.


Feitosa and Brandão (2008) - Body densely and irregularly rugose; metanotal groove obsolete; teeth of propodeal lobes well developed and projected over petiolar peduncle; petiolar node high and subtriangular; pilosity on dorsum of postpetiole exceptionally dense; first tergite of gaster completely devoid of long flexuous hairs. The well developed teeth of propodeal lobes allied to the dense pilosity on postpetiole dorsum separate this species from the related Lachnomyrmex amazonicus, Lachnomyrmex nordestinus, Lachnomyrmex plaumanni, and Lachnomyrmex victori. Gynes of L. longinoi can be confounded with Lachnomyrmex scrobiculatus by the subtriangular petiolar node and the presence of long hairs on first gastral tergite. However, gynes of L. scrobiculatus present an anteroventral projection in the postpetiole, which is absent in this species.

Keys including this Species


Distribution based on Regional Taxon Lists

Neotropical Region: Costa Rica (type locality), Honduras, Nicaragua, Panama.

Distribution based on AntMaps


Distribution based on AntWeb specimens

Check data from AntWeb


Very little is known about the biology of these cryptic ants. Workers are frequently found in leaf litter and soil samples processed in Winklers or Berlese extractors, but these ants are never especially abundant within samples. When a dealate gyne is found associated with workers in 1m2 samples of leaf litter, normally it is found singly, which suggests that colonies are relatively small and apparently monogynic; workers and nests are extremely difficult to spot in the field, because the workers are very slow moving and well camouflaged; if there is any leaf-litter nest structure, it is destroyed during sifting, but our impression is that they do not construct any permanent nidal structure. Species of Lachnomyrmex apparently nest within the leaf litter, inside natural cavities of the superficial soil layers, fallen logs, and rotten wood, as evidenced by the large number of soil-covered individuals collected, from information recorded in specimen label data, and from observations of collectors. Workers forage alone, in the leaf litter and in the low vegetation, occasionally among epiphytes and moss, probably preying on small soft-bodied arthropods and possibly harvesting plant exudates. (Feitosa and Brandao 2008)



The following information is derived from Barry Bolton's Online Catalogue of the Ants of the World.

  • longinoi. Lachnomyrmex longinoi Feitosa & Brandão, 2008: 25, figs. 9, 18 (w.q.) COSTA RICA.

Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.



Holotype HL 0.72; HW 0.74; ML 0.24; SL 0.43; EL 0.16; WL 0.84; PSL 0.19; PL 0.35; PPL 0.18; GL 0.88; TL 3.21; CI 102; SI 58; OI 21. Workers (n=20). HL 0.66–0.72; HW 0.65–0.74; ML 0.22–0.25; SL 0.39–0.46; EL 0.13– 0.17; WL 0.76–0.87; PSL 0.16–0.19; PL 0.31–0.36; PPL 0.16–0.19; GL 0.85–0.94; TL 2.98–3.32; CI 98–102; SI 58–66; OI 20–24.

Color dark brown to black, with lighter appendages. Body densely covered by vermiculate short rugae, forming irregular areolae on head and promesonotum, and slightly sparser on mesopleura and lateral surfaces of propodeum; mandibles with short longitudinal striae restricted to basal portion; petiole and postpetiole irregularly rugose. Abundant pilosity on head and promesonotum dorsum; dorsum of petiolar node with about six long hairs; dorsum of postpetiole densely covered by long flexuous hairs; first gastral tergite entirely devoid of long hairs.

Head as long as broad, with vertexal margin weakly convex; frontal lobes subquadrate; eyes with about seven facets on maximum diameter. Promesonotum elevated well above the level of propodeum in profile; metanotal groove virtually obsolete; propodeal spines straight; teeth of propodeal lobes widen basally and slight longer than the half-length of propodeal spines. Petiolar node elevated and subtriangular in lateral view; postpetiole strongly convex dorsally and without ventral projections.


(n=5). HL 0.65–0.79; HW 0.65–0.79; ML 0.21–0.24; SL 0.39–0.44; EL 0.17–0.20; WL 0.87–1.06; PSL 0.16–0.20; PL 0.36–0.43; PPL 0.17–0.24; GL 0.96–1.12; TL 3.24–3.86; CI 100–102; SI 56–61; OI 26–27.

Similar to worker. In addition, eyes with around 12 facets at maximum; wings with the basic pattern of venation for the genus; propodeal spines and teeth of propodeal lobes reduced; petiolar node comparatively lower; ventral face of postpetiole moderately projected; surface of first gastral tergite covered by long flexuous hairs, relatively dense anteriorly, becoming sparser posteriorly.

Type Material

Holotype worker. COSTA RICA: Guanacaste: Est. Pitilla, 9km S Sta. Cecília, LN 330200_380200, 16– 18.viii.1993, P. Ríos col., no. INBIOCRI0001657358 Instituto Nacional de Biodiversidad. Paratypes. same data as holotype, no INBIOCRI001657147 (1 worker) Museu de Zoologia da Universidade de Sao Paulo; no INBIOCRI0001657202 (1 worker) [INBC]; COSTA RICA: Alajuela: Río San Lorencito, 1990, P. Hammond col. (2 workers) The Natural History Museum; same data (1 worker) [MZSP]; Guanacaste: Pitilla Field Station, 2.v.1995, R. Anderson col., no. 17721 (1 worker) William and Emma Mackay Collection; Heredia: La Selva, 15.iv.1985, J. Memmott col. (3 workers) [BMNH]; Limón: Cerro Cocori, Fca. de E. Rojas, vi.1991, E. Rojas col., no. INBIOCRI000636130 (1 worker) [INBC]; 30km N Cariari, i.1993, E. Rojas col., no. INBIOCRI000675271 (1 worker) [INBC]; Puntarenas: Península Osa, Aenn. Fund. Neotrop.,, R. Anderson col., no. 18686/18687 (5 workers and 1 gyne) [WPMC]; same data (1 gyne) [MZSP]; same data (1 worker) California Academy of Sciences; same data (1 worker) Laboratório de Mirmecologia CEPEC / CPDC; same data (1 worker) National Museum of Natural History; Cerro Helado, 15km NE Rincón,, R. Anderson col., no. 18689 (1 worker and 1 gyne) [WPMC]; Península Osa, Cerro Helado,, R. Anderson col., no. 18685 (2 workers and 1 gyne) [WPMC].


This species is named in honor of Dr. John “Jack” Longino in recognition of his many years of devoted work on the ants of Costa Rica and for his valuable support during the elaboration of this work.


  • Feitosa, R.M. & Brandão, C.R.F. 2008. A taxonomic revision of the Neotropical myrmicine ant genus Lachnomyrmex Wheeler (Hymenoptera: Formicidae). Zootaxa 1890, 1-49.

References based on Global Ant Biodiversity Informatics

  • Feitosa, R.M. and C.R.F Brandao. 2008. A taxonomic revision of the Neotropical myrmicine ant genus Lachnomyrmex Wheeler (Hymenoptera: Formicidae). Zootaxa 1890:1-49
  • INBio Collection (via Gbif)
  • Longino J. T. 2013. Ants of Nicargua. Consulted on 18 Jan 2013.
  • Longino J. T. L., and M. G. Branstetter. 2018. The truncated bell: an enigmatic but pervasive elevational diversity pattern in Middle American ants. Ecography 41: 1-12.
  • Longino J. T., and R. K. Colwell. 2011. Density compensation, species composition, and richness of ants on a neotropical elevational gradient. Ecosphere 2(3): 16pp.
  • Longino J. et al. ADMAC project. Accessed on March 24th 2017 at