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| Author(s): |
Emília Zoppas de Albuquerque
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Ribeirão Preto. |
| Institution: | Universidade de São Paulo (USP). Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto (PCARP/BC) |
| Defense date: | 2014-12-03 |
| Examining board members: |
Carlos Roberto Ferreira Brandão;
Eduardo Andrade Botelho de Almeida;
Fernando Barbosa Noll;
Antonio José Mayhé Nunes;
Kelli dos Santos Ramos
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| Advisor: | Carlos Roberto Ferreira Brandão |
| Abstract | |
The tribe Attini are remarkable fungus-growing ants, composed by 16 extant genera and one ichnofossil. The attine genus Cyphomyrmex consists of small-sized monomorphic ants, with opaque integument, inhabiting the leaf-litter and nesting in the soil, between small roots, in hollow trees or in decomposing twigs. The species are distributed in Neotropical and Nearctic regions. The genus Cyphomyrmex was described by Mayr in 1862 based on a single species, Cyphomyrmex minutus. The genus was after that, divided by Kempf in two species group: \"Strigatus group\" and \"Rimosus group\". I present here a revision of the Rimosus species group of the ant genus Cyphomyrmex and this study represents the first attempt to analyze the internal phylogenetic relationships of the species in the Rimosus group based on the external morphology of workers. The comparative study of external morphology of the 43 terminals results in a matrix with 56 characters, of which 38 hypotheses equally parsimonious were found (281 steps in each hypothesis). The analysis with implied weighting were also performed with several values of the concavity constant k. In this case, using the concavity value K=3, only one tree was generated (Fit= 20.90); for others concavity values (K=5, K=7 and K= 10) were found three trees (Fit= 18.86, 15.66 and 12.54, respectively). The phylogenetic analysis demonstrates the monophyly of the Rimosus group, excluding some species of Cyphomyrmex (C. costatus, C. longiscapus, C. muelleri and C. wheeleri). Because the relationships between this four species excluded from Rimosus group with Strigatus group and other genera of attine were not clear, we chose to regard them as incertae sedis in Cyphomyrmex and I suggest that additional analysis are necessary to make a taxonomic decision. The monophyly of the Cyphomyrmex Rimosus group is supported by at least five synapomorphies: (1) yeast-growing ants; (2) vertexal carinae divergent to the frontal carinae; (3) preocular carinae medially below of the eyes; (4) incomplete antennal scrobe; (5) strong narrowing of the frontal carinae. I recognize two species complexes in the Rimosus group: the minutus and rimosus complex. However, considering the wide geographic distribution, range of intraspecific variability and nomenclatural problems, I suggest that both complexes need additional studies before make certain changes in the nomenclature. Twelve new species are recognized in the genus Cyphomyrmex, six of which were associated with gynes and one with the male. Further, for the first time the male of C. cornutus is described and the gyne of C. laevigatus, increasing to thirty-one species and two fossils valid in the Cyphomyrmex Rimosus group. (AU) | |
| FAPESP's process: | 10/02560-5 - A taxonomic revision and phylogenetic analysis of the Rimosus species group of the ant genus Cyphomyrmex (Hymenoptera, Formicidae, Attini) |
| Grantee: | Emília Zoppas de Albuquerque |
| Support Opportunities: | Scholarships in Brazil - Doctorate |