Bariamyrma

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Bariamyrma
Bariamyrma hispidula
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Solenopsidini
Genus: Bariamyrma
Lattke, 1990
Type species
Bariamyrma hispidula
Diversity
1 species
(Species Checklist)

Bariamyrma hispidula casent0102363 profile 2.jpg

Bariamyrma hispidula

Bariamyrma hispidula casent0102363 dorsal 1.jpg

Specimen Label

Evolutionary Relationships
Solenopsidini

Stegomyrmex





Dolopomyrmex



Rogeria






Bariamyrma



Rogeria






Solenopsis




Kempfidris



Tropidomyrmex






Austromorium, Monomorium, Oxyepoecus




Megalomyrmex






Tyrannomyrmex




some Monomorium



Epelysidris







Anillomyrma



Myrmicaria





Monomorium




Syllophopsis



Adelomyrmex, Baracidris, Cryptomyrmex













Based on Ward et al., 2014

Only known from a few widely scattered collections of single queens of a single species - Bariamyrma hispidula.

Identification

Lattke's (1990) discussion of placement of the genus in relation to other Mymricinae is helpful for making determinations:

The placement of this genus of apparently lower Myrmicinae into established tribes or genus groups at this moment is not clear. On account of its apomorphies it is obviously not a member of the Myrmica nor Tetramorium genera groups. If we consider the Pheidologeton group and the characters listed by Ettershank (1966: 115) as well as those pointed out by Bolton (1987: 265) there seems to be no affinity. The lack of a clearly defined antennal club and presence of well developed frontal carinae in Bariamyrma plead against such a grouping. The only other universal characters within pheidologetines are the lack of a prominent median clypeal seta and a closed radial cell of the fore wing, but both are plesiomorphic states and of limited phylogenetic value. To place it in the Pheidolini or Myrmecini, polyphyletic assemblages of genera, would be of no heuristic value.

The specimen does share a number of characters with Lordomyrma such as the mandibular structure, convex clypeus, frontal lobes, frontal carinae, antennae, and propodeal spiracles set well forward from the margin of the declivity. Yet in Lordomyrma the clypeus is clearly bicarinate, and distinct, albeit flat, antennal scrobes are formed. In this genus the petiolar peduncle tends to be shorter, the humeral angles somewhat sharper, tibial spurs are wanting, the sting presents no flange and the propodeal spiracle is below the base of the propodeal spine. Wheeler (1919: 105) illustrates the forewing of a male Lordomyrma and it is quite similar to Bariamyrma except for the anal vein, which does not extend beyond cu-a. Wheeler also notes the presence of hairy wings. A survey of the other genera related to Lordomyrma, such as Cyphoidris Weber, Lachnomyrmex Wheeler, Dacetinops Brown & Wilson, and Indomyrma Brown reveals distinct antennal scrobes and clubs, the lack of apical spurs on the meso- and metatibiae, and a raised, usually bicarinate, median clypeus. The sting in Lachnomyrmex tends to be flattened, and in Cyphoidris terminates in a narrow spatulate appendage. Lachnomyrmex has its propodeal spiracles set well back from the declivitous face margin, but Cyphoidris and Dacetinops have them positioned quite posterad. Accepting Bariamyrma as a member of this assortment of genera, and even though it has several apomorphies in relation to them, such as the reduced palpal segmentation and form of the sting, on the whole it seems that Bariamyrma is a somewhat primitive member of the group.

Distribution

Known from Costa Rica, Paraguay and Venezuela.

World distribution based on political regions. View/Edit Data
Bariamyrma Distribution.png Worlddistribution legend.jpg

Species richness

Species richness by country based on regional taxon lists (countries with darker colours are more species-rich). View Data

Bariamyrma Species Richness.png

Biology

Castes

Described and only known from the queen caste.

Male Morphology

 • Caste unknown

Nomenclature

The following information is derived from Barry Bolton's New General Catalogue, a catalogue of the world's ants.

  • BARIAMYRMA [Myrmicinae: Stenammini]
    • Bariamyrma Lattke, 1990a: 173. Type-species: Bariamyrma hispidula, by original designation.

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

Description

Queen

Ants belonging to the subfamily Myrmicinae.

1. Mandibles triangular, with a series of 9 teeth on the masticatory margin, the apical tooth being the largest.

2. Palp formula 3,2 (in situ count).

3. Anterior clypeal border convex, medially produced into a blunt point and covering basal mandibular margins.

4. Clypeus posteriorly narrowly inserted between the widely separated frontal lobes.

5. Clypeus with longitudinal rugae, not distinctly bicarinate but with a prominent anteromedian carina.

6. Lateral portions of clypeus not posteriorly raised into a shield-wall in front of the antennal fossae.

7. Anterior margin of clypeus with hairs but without a single prominent median seta.

8. Frontal carinae extend posteriorly to slightly behind the eyes; almost as long as the scapes and posteriorly diverging one from another.

9. No evident antennal scrobe present.

10. Antennae with 12 segments, funiculus clavate with a vague 3-merous club; each funicular segment sharply constricted one from another.

11. Frontal triangle well defined, smooth and shining.

12. Propodeal spiracle situated slightly above mid-height of sclerite, close to junction of metapleuron and anterad of teeth, well back from the edge of the declivitous face.

13. Declivitous propodeal face with a pair of sharply pointed triangular lateral teeth joined by carinae to the well developed, bluntly pointed inferior propodeal plates.

14. Posteroventral alitrunk with a median convex emargination, not open and extending anterad of hind coxae.

15. Metasternal process absent.

16. Strongly pedunculate petiole, node conical with a bluntly pointed apex, petiolar ventrum with a low longitudinal carina, no prominent process.

17. Petiolar spiracle is at mid-peduncular length.

18. Postpetiolar node dome-shaped as seen laterally, and campaniform dorsally; prominent transverse sub postpetiolar process.

19. Sting weakly sclerotized and ending in a prominent lobular flange.

20. Apex of meso- and metatibiae each with a single simple spur.

21. Strongly sculptured cuticle except for gaster.

Features of the anterior wing venation include Mf1 branching out quite distad of cu-a, the absence of lr and r-m, the continuity of 2r and Rsf2-3. One cubital cell is present and the radial cell is closed. The posterior wing has only one cell, neither Rs, M, nor CuA extends after r-m, and M-Cu does not reach the wing base. A thickened cu-a reaches toward but does not touch the brief and thick anal vein. Wings with abundant decumbent pilosity, borders of posterior wings with a fringe of short hairs, but such a fringe lacking about the anterior wings.

Etymology

The generic name Baria is the name of a river next to the Cerro Neblina expedition basecamp.

References

  • Bolton, B. 1994. Identification guide to the ant genera of the world. Cambridge, Mass.: Harvard University Press, 222 pp. (page 106, Bariamyrma in Myrmicinae, Stenammini)
  • Bolton, B. 1995a. A taxonomic and zoogeographical census of the extant ant taxa (Hymenoptera: Formicidae). J. Nat. Hist. 2 29: 1037-1056 (page 1048, Bariamyrma in Myrmicinae, Stenammini)
  • Bolton, B. 1995b. A new general catalogue of the ants of the world. Cambridge, Mass.: Harvard University Press, 504 pp. (page 80, Bariamyrma in Myrmicinae, Stenammini)
  • Bolton, B. 2003. Synopsis and Classification of Formicidae. Mem. Am. Entomol. Inst. 71: 370pp (page 202, Bariamyrma in Myrmicinae, Stenammini)
  • Jaffe, K. 1993. El mundo de las hormigas. Baruta, Venezuela: Equinoccio (Ediciones de la Universidad Simón Bolívar), 188 pp. (page 11, Bariamyrma in Myrmicinae, Leptothoracini)
  • Lattke, J. E. 1990a. A new genus of myrmicine ants (Hymenoptera: Formicidae) from Venezuela. Entomol. Scand. 21: 173-178 (page 173, Bariamyrma as genus)