Leptanilloides biconstrictus

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Leptanilloides biconstrictus
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Dorylinae
Genus: Leptanilloides
Species: L. biconstrictus
Binomial name
Leptanilloides biconstrictus
Mann, 1923

Leptanilloides biconstricta casent0104676 profile 2.jpg

Leptanilloides biconstricta casent0104676 dorsal 1.jpg

Specimen Label

Described from a small series of workers, taken with callows, but without sexual or immature phases, from beneath a deeply embedded stone,near a stream. (Mann 1923)


A member of the Leptanilloides biconstrictus species-group.

Keys including this Species


Tumupasa, Bolivia.

Distribution based on Regional Taxon Lists

Neotropical Region: Bolivia (type locality).

Distribution based on AntMaps


Distribution based on AntWeb specimens

Check data from AntWeb

Countries Occupied

Number of countries occupied by this species based on AntWiki Regional Taxon Lists. In general, fewer countries occupied indicates a narrower range, while more countries indicates a more widespread species.

Estimated Abundance

Relative abundance based on number of AntMaps records per species (this species within the purple bar). Fewer records (to the left) indicates a less abundant/encountered species while more records (to the right) indicates more abundant/encountered species.



Images from AntWeb

Leptanilloides biconstricta casent0104676 profile 2.jpg
Worker. Specimen code casent0104676. Photographer April Nobile, uploaded by California Academy of Sciences. Owned by AMNH, New York, NY, USA.
Leptanilloides biconstricta casent0104700 profile 4.jpgLeptanilloides biconstricta casent0104700 profile 5.jpgLeptanilloides biconstricta casent0104700 label 1.jpg
Specimen code casent0104700. .


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

  • biconstrictus. Leptanilloides biconstricta Mann, 1923: 14, fig. 1 (w.) BOLIVIA.
    • Type-material: lectotype worker (by designation of Brandão, Diniz, et al. 1999: 23), 6 paralectotype workers.
    • Type-locality: lectotype Bolivia: Beni, Tumupasa (W.M. Mann); paralectotypes with same data.
    • Type-depositories: USNM (lectotype); MZSP, USNM (paralectotypes).
    • Status as species: Borgmeier, 1955: 653 (redescription); Kempf, 1972a: 129; Bolton, 1995b: 229; Brandão, Diniz, et al. 1999: 23 (redescription); Donoso, et al. 2006: 60 (in key); Borowiec, M.L. & Longino, 2011: 27 (in key); Delsinne, et al. 2015: 7 (in key); Palacio, 2019: 610.
    • Distribution: Bolivia, Colombia, Venezuela.

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



Length 1.80-2 mm. Head subquadrate, very slightly narrowed behind, more than twice as long as broad, sides nearly straight and parallel; occipital corners rounded, border feebly concave. Mandibles slender; their blades edentate. Anterior border of clypeus straight. Antennm stout, scapes clavate, extending about three-eighths the distance to occipital borders;first funicular joint rounded, broader and longer than the second; joints 2-10 slightly transverse, gradually increasing in size toward apex; terminal joint about as long as the two preceding together. Thorax and epinotum elongate, slender, flat above; pronotum from above broadest at humeri, with sides feebly convex; mesoepinotum seen from above, quadrate, two and a half times as long as broad, with nearly straight sides; epinotal declivity very short and rounding into the basal portion. Petiolar node from above a little longer and two-thirds as broad as the post petiole, very slightly narrowed from front to rear and with straight sides; in profile slightly convex above, the ventral outline convex at anterior half and concave behind, projected anteriorly as a blunt cone. Postpetiole in profile rather strongly convex beneath, feebly above; from above a little longer than broad, feebly broadened from front to rear, with straight anterior and posterior borders and nearly straight sides. First gastric segment a little longer than the second or third. Legs long, the femora swollen and the tibiea enlarged apically.

Shining; head with abundant, separated, coarse, punctures; thorax and abdomen, with much finer and sparser punctures. Head, body and appendges with abundant, rather coarse, short and erect, brownish hairs.

Color brownish red.

Brandão et al. 1999. Fig 53-59

Brandão et al. (1999) - Paralectotype (MZUSP) (in mm): HL 0.49, HW 0.28, SL 0.15, WL 0.54, CI 57, SI 55, SRI 76.

The combination of the following characters distinguishes L. biconstrictus from all other species in the genus: postpetiole in profile nearly as deep dorsoventrally as first gastral segment, head sculpture fine with c. 15 shallow foveolae covering a transverse straight line at head midlength, and the flange over the metapleural gland opening sharply pointed posteriorly. Other relevant characters include: petiole is longer than the postpetiole and the ventral process of the petiole does not have a posterior angle. In relation to the venom apparatus, the spiracular plate median connection anterior margin is straight (Fig. 55); the quadrate plate antero-dorsal corner bears a long projection and has the apex acute; the anal plate is longer than wide and weakly sclerotized with 6 sensillae; the oblong plate (Fig. 57) has the postincision directed towards the dorsal margin, although it does not touch it and the ventral arm of the apodema is reduced; the fulcral arm is relatively small and in the shape of a rounded tubercle; the gonostylus presents approximately 80 small sensillae; the furcula is convex, with long lateral arms; the sting bulb base is rounded (Fig. 59), with the basal ridge slightly larger than the width of the furcula, the anterolateral process long and anterior to the articular process and the short articular process in the basal region of the sting bulb.

Type Material

Brandão et al. (1999) - Lectotype worker, BOLIVIA, Beni, Tumupasa, W. M. Mann, NMNH type 25705 (examined, designated here). Worker paralectotypes, NMNH, four worker paralectotypes (Museum of Comparative Zoology type 20289); two paralectotypes (MZUSP, one dissected, preserved on glass slide), all same series as lectotype (examined).

W. M. Mann travelled along the Beni River in Bolivia as a member of the Mulford Biological Expedition, between 1921 and 1922. Other ant species collected at the type locality of Leptanilloides biconstrictus (Tumupasa), deposited at the MZUSP (Megalomyrmex balzani, see Brandao, 1990) bear a label saying ‘Dec.’, so the date of the collection may be December of 1921.


  • Borgmeier, T. 1955. Die Wanderameisen der neotropischen Region. Stud. Entomol. 3: 1-720 (page 653, see also)
  • Brandão, C. R. F.; Diniz, J. L. M.; Agosti, D.; Delabie, J. H. C. 1999. Revision of the Neotropical ant subfamily Leptanilloidinae. Syst. Entomol. 24: 17-36 (page 23, see also)
  • Mann, W. M. 1923. Two new ants from Bolivia. (Results of the Mulford Biological Exploration. - Entomology.). Psyche (Camb.) 30: 13-18 (page 14, fig. 1 worker described)

References based on Global Ant Biodiversity Informatics

  • Borgmeier T. 1955. Die Wanderameisen der neotropischen Region. Studia Entomologica 3: 1-720.
  • Delsinne T., G. Sonet, and D. A. Donoso. 2015. Two new species of Leptanilloides Mann, 1823 (Formicidae: Dorylinae) from the Andes of southern Ecuador. European Journal of Taxonomy 143: 1–35.
  • Fernández, F. and S. Sendoya. 2004. Lista de las hormigas neotropicales. Biota Colombiana Volume 5, Number 1.
  • Kusnezov N. 1953. La fauna mirmecológica de Bolivia. Folia Universitaria. Cochabamba 6: 211-229.
  • Mann W. M. 1923. Two new ants from Bolivia. (Results of the Mulford Biological Exploration. - Entomology.). Psyche (Cambridge) 30: 13-18.