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| Author(s): |
Sarah Siqueira de Oliveira
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | Ribeirão Preto. |
| Institution: | Universidade de São Paulo (USP). Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto (PCARP/BC) |
| Defense date: | 2009-03-16 |
| Examining board members: |
Dalton de Souza Amorim;
Carlos José Einicker Lamas;
Charles Morphy Dias dos Santos
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| Advisor: | Dalton de Souza Amorim |
| Abstract | |
Mycetophilidae (Diptera) is the second largest and most diversified family of the infraorder Bibionomorpha. Traditionally, it includes seven subfamilies: Sciophilinae, Gnoristinae, Mycomyiinae, Leiinae, Manotinae, Allactoneurinae, and Mycetophilinae. The genera Dziedzickia and Schnusea, issues of this study, belong to the subfamily Gnoristinae. Dziedzickia was described by Johannsen in 1909. Most of its species is known from the Neotropical Region (38 extant species), but they are also found in the Palaearctic (2), Nearctic (7), Oriental (1), and Afrotropical (5) Regions. The Neotropical genus Schnusea was stated by Edwards, in 1933. Currently, five extant species are recognized for this genus. One of the characteristics thought to be apomorphic for Schnusea is the absence of M1+2 wing venation, which may be plesiomorphic for the species of Dziedzickia, suggesting that the latter could be paraphyletic in relation to the former. The study of diversity resulted in the recognition of 47 Neotropical valid species, including six as new species of Dziedzickia and three as junior synonyms, and in the inclusion of Schnusea into the synonymy of Dziedzickia. Furthermore, a key to the Neotropical species of Dziedzickia is herein presented. For the phylogenetic analysis 41 morphological characters of adult individuals have been surveyed, resulting in a sampling of 49 (males only) and 55 (both males and females) terminals. Heuristic searches were performed with equal weights and implied weighting, followed by a sensitivity analysis. The sensitivity analysis was carried out in order to access to measure how often each clade appears for different values of k. No differences between the sensitivity analysis done with males only and those performed with both males and females at same time were detected. In every analysis, species assigned to Schnusea form a well-supported clade within Dziedzickia and Gnoristinae is recovered as a monophyletic group¬¬¬. The genus Dziedzickia is monophyletic after the inclusion of Schnusea. The methodology of sensivity analysis shown to be a useful tool for measure support, indicating the robustness of certain clades when different analysis parameters are utilized. Two well-circumscribed biogeographic patterns were found for Neotropical species of Dziedzickia: one composed of species confined to Southern South America and one formed exclusively by species from Northern South America and Caribbean Region. Furthermore, there is a clade composed of Afrotropical species only, indicating that Dziedzickia has different subgroups with intercontinental disjunction. (AU) | |
| FAPESP's process: | 06/58085-8 - Revision and phylogenetic analysis of Dziedzickia johannsen (Diptera, Bibionomorpha, Mycetophilidae) |
| Grantee: | Sarah Siqueira de Oliveira |
| Support Opportunities: | Scholarships in Brazil - Master |