Evaluating the role of morphological characters in the phylogeny of some trypanosomatid genera (Excavata, Kinetoplastea, Trypanosomatida)

Author(s)

da Silva-Junior, Renato ^{[1, 2]} ; Paiva, Thiago da Silva ^{[3, 4]}

Affiliation

^[1] Inst Oswaldo Cruz, FIOCRUZ, Lab Interdisciplinar Vigilancia Entomol Diptera &, BR-21040900 Rio De Janeiro, RJ - Brazil

^[2] Univ Fed Fluminense, Programa Posgrad Ciencias & Biotecnol, Niteroi, RJ - Brazil

^[3] Univ Sao Paulo, Inst Biociencias, Lab Evolutionary Protistol, BR-05508090 Sao Paulo, SP - Brazil

^[4] Univ Fed Para, Inst Ciencias Biol, Lab Biol Mol Francisco Mauro Salzano, BR-66075110 Belem, Para - Brazil

• Document type: Journal article
• Source: CLADISTICS; v. 34, n. 2, p. 167-180, APR 2018.
• Web of Science Citations: 1

Abstract

Over the last three decades, it has been progressively assumed that morphology has become obsolete for trypanosomatid systematics. Traditional taxonomy, based on the occurrence of specific kinds of cell morphotypes during life cycles and the morphometry of such cells, is often rejected by molecular phylogenies inferred mostly from 18S rDNA alone or combined with GAPDH. In such context, we hypothesized the affinities of 35 representatives of seven trypanosomatid genera from separated and combined cladistics analyses of morphological and 18S matrices. Morphology is shown to be more consistent and to have stronger synapomorphy retention than the 18S data. The strict consensus of cladograms from separated analyses was mostly unresolved, while combined analysis produced a meaningful and robust phylogenetic pattern, as evidenced by partition congruence index, Bremer support and frequencies of groups present/contradicted. The results (1) corroborate the separation of Angomonas and Strigomonas from Crithidia, which is now shown to be monophyletic, (2) support the revalidation of the genus Wallaceina, and (3) place the genera Herpetomonas, Leptomonas and Phytomonas within a single clade. Overall, we demonstrate the belief that morphological characters are inferior to molecular ones for trypanosomatid systematics is a consequence of neglecting their inclusion in phylogenetic analyses. (C) The Willi Hennig Society 2017. (AU)

• FAPESP's process: 15/17856-0 - Multidisciplinary characterization and geographic distribution of benthic marine Ciliophora from Brazilian coast with emphasys on hypotrichs s. l. (Euplota et Hypotricha)
• Grantee: Thiago da Silva Paiva
• Support Opportunities: Scholarships in Brazil - Post-Doctoral