Showing posts with label 2011. Show all posts
Showing posts with label 2011. Show all posts

Soto Vivas, A, J. Liria & E. De Luna. 2011

Morfometria geométrica y filogenia en Rhodniini de Venezuela (Hemiptera, Reduvidae). ACTA ZOOLOGICA MEXICANA 27(1): 87-102.

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RESUMEN. La tribu Rhodniini incluye los géneros Rhodnius Stål y Psammolestes Bergroth. Evidencias enzimática y molecular sugieren la monofilia de la tribu. La mayoría de las especies son selváticas encontrándose en palmas y en nidos de aves. Tradicionalmente ambos géneros fueron considerados grupos relacionados; no obstante, estudios moleculares cuestionan la monofilia de Rhodnius. El objetivo fue analizar filogenéticamente la variación morfométrica en la arquitectura alar, como apoyo a la taxonomía y sistemática en Rhodniini. Se fotografiaron 524 alas de cinco representantes de Rhodniini: Psammolestes arthuri (Pinto) (n = 89), Rhodnius pictipes Stål, (n = 21), R. robustus Larrousse (n = 24), R. prolixus Stål, (n = 16) y R. neivai Lent (n = 22). Como grupos externos se estudiaron cuatro representantes de Triatomini: Eratyrus mucronatus Stål (n = 15), Panstrongylus rufotuberculatus (Champion) (n = 45), P. geniculatus (Latreille) (n = 183) y Triatoma maculata (Erichson) (n = 109). Se registraron configuraciones de coordenadas (x, y) y se alinearon mediante Análisis Generalizado de Procrustes. Se efectuaron Análisis de Covarianza con proporción de grupos re-clasificados y MANOVA. Luego, las variables de la forma alar (intervalos de confianza de las deformaciones relativas) y el tamaño del centroide se analizaron cladísticamente. Los análisis estadísticos de varianza no encontraron diferencias significativas (Kruskal-Wallis) en el tamaño isométrico del ala en las especies P. arthuri – R. neivai – R. pictipes; R. robustus – R. prolixus – T. maculata y entre P. rufotuberculatus – P. geniculatus. La reclasificación a posteriori fue perfecta para E. mucrunatus 100% y R. pictipes, seguidas de T. maculata con 96%, R. neivai 95%, P arthuri 93.2%; R. prolixus 87.5%, P. geniculatus 87.4%, P. rufotuberculatus 84.4%, y R. robustus 76%. Los análisis cladísticos con parsimonia seleccionaron dos árboles de mínima longitud (L = 4.461 IC = 0.973 e IR = 0.979). El consenso estricto muestra la monofilia de Panstrongylus (rufo-tuberculatus + geniculatus) y Triatoma + Rhodniini (Rhodinus + Psammolestes), pero internamente la parafilia de Rhodnius respecto a Psammolestes. Estos resultados son congruentes con análisis molecuares previos en Rhodniini, lo cual revela la información filogenética de caracteres morfométricos como apoyo a los estudios sistemáticos, permitiendo combinar por primera vez en este grupo los análisis de morfometría geométrica y métodos filogenéticos.
Palabras clave: Triatominae, Rhodnius, Psammolestes, morfometría, sistemática.

ABSTRACT. Tribe Rhodniini includes Rhodnius Stål and Psammolestes Bergroth. Enzymatic and
molecular evidence suggest the tribe is monophyletic. Most species are wild, living in palms and birdnests. Traditionally both genera were considered related; nevertheless, molecular studies don’t support the Rhodnius monophyly. The goal was to phylogenetically analyze morphometric variation in wing architecture in support of Rhodniini taxonomy and systematics. We photographed 524 wings of five representatives of Rhodniini: Psammolestes arthuri (Pinto) (n = 89), Rhodnius pictipes Stål (n = 21), R. robustus Larrousse (n = 24), R. prolixus Stål (n = 16), and R. neivai Lent (n = 22). As outgroups we studied four representatives of Triatomini: Eratyrus mucronatus Stål (n = 15), Panstrongylus rufotuberculatus (Champion) (n = 45), P. geniculatus (Latreille) (n = 183), and Triatoma maculata (Erichson) (n = 109). Landmark coordinate (x, y) configurations were registered and aligned by Generalized Procrustes Analysis. Covariance Analyses were implemented with proportions of re-classified groups and MANOVA. Then, wing shape variables (confidence intervals from relative warps) and centroid size were cladistically analysed. Statistical analyses of variance found not significant differences in wing isometric size (Kruskal-Wallis) among P. arthuri–R. neivai–R. pictipes; R. robustus–R. prolixus–T. maculata and between P. rufotuberculatus–P. geniculatus. The a posteriori re-classification was perfect in E. mucrunatus 100% and R. pictipes, followed by T. maculata 96%, R. neivai 95%, P arthuri 93.2%; R. prolixus 87.5%, P. geniculatus 87.4%, P. rufotuberculatus 84.4%, and R. robustus 76%. Cladistic analyses under parsimony selected two most parsimonious trees (L=4.461 IC=0.973 and IR=0.979), where the strict consensus showed a monophyletic group with Panstrongylus (rufotuberculatus + geniculatus) and Triatoma + Rhodniini (Rhodinus + Psammolestes), but internally it shows the paraphyly of Rhodnius regarding Psammolestes. The congruence between these results and previous molecular analyses in Rhodniini, reveal the phylogenetic information of our morphometric characters as support to systematic studies, allowing the combination of geometric morphometrics and phylogenetic methods for the first time in this group.
Key words: Triatominae, Rhodnius, Psammolestes, geometric morphometrics, systematics, cladistic analyses.

Aguilar-Medrano R, B. Frédérich, E. De Luna & E. Balart-Paez. 2011

Patterns of morphological evolution of the cephalic region in Damselfishes (Perciformes, Pomacentridae) of the Eastern Pacific. BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY 102 (3): 593-613.

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Abstract
Pomacentridae are one of the most abundant fish families inhabiting reefs of tropical and temperate regions. This family, comprising 29 genera, shows a remarkable diversity of habitat preferences, feeding, and behaviours. Twenty-four species belonging to seven genera have been reported in the Eastern Pacific region. The present study focuses on the relationship between the diet and the cephalic profile in the 24 endemic damselfishes of this region. Feeding habits were determined by means of underwater observations and the gathering of bibliographic data. Variations in cephalic profile were analyzed by means of geometric morphometrics and phylogenetic methods. The present study shows that the 24 species can be grouped into three main trophic guilds: zooplanktivores, algivores, and an intermediate group feeding on small pelagic and benthic preys. Shape variations were low within each genus except for Abudefduf. Phylogenetically adjusted regression reveals that head shape can be explained by differences in feeding habits. The morphometric phylogeny recovered the subfamily Stegastinae and the relationship between Abudefduf troschelii and Chromis species. The cephalic profile of damselfishes contains a clear and strong phylogenetic signal.
© 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 102, 593–613.
ADDITIONAL KEYWORDS: Gulf of California – head shape – phylogenetic morphometrics – reef fishes – trophic niche.