This paper evaluated the intraspecific variation and diet of Engystomops pustulosus in three localities (Colosó, Santa Inés, and El Roble) of the department of Sucre, Colombia. Thirty specimens were collected by locality and the diet composition was determined. We characterized the phenotypic variation by means of skull geometric morphometrics and ten body measures. Finally, the relationship between morphogeometric variables (shape and size) and diet were evaluated. We found significant differences between skull conformation and localities, and between localities and the centroid size. Termites were the most important type of prey, followed by ants and mites. The diet composition did not correlate with the body measures; however, an analysis of Partial Least-Squares showed a correlation between the composition of the diet and skull conformation.

Variación morfogeométrica en Phrynus barbadensis (Pocock, 1893) (Amblypyghi: Phrynidae) de Colombia RESUMEN. Amblypygi es un pequeño orden de arácnidos con características similares a arañas. En Colombia, este orden ha sido poco estudiado, y la mayoría de las investigaciones se han centrado a niveles taxonómicos. Recientemente, la morfometría geométrica ha probado ser una herramienta útil para determinar diferencias en escorpiones y arañas. Debido a esto, utilizamos morfometría geométrica para determinar variación intraespecifica en tres poblaciones colombianas de Phrynus barbadensis. Digitalizamos 16 puntos anatómicos sobre el caparazón y 15 en la patela combinando hitos e hitos deslizantes; las coordenadas fueron analizadas mediante análisis generalizado de Procrustes. Se implementó el Análisis de Variables Canónicas con proporción de grupos reclasificados y MANOVA. Se determinaron diferencias significativas en la conformación del caparazón entre poblaciones; todos los especímenes fueron 80% correctamente clasificados. Los análisis estadísticos de varianza (ANOVA) determinaron diferencias significativas en los tamaños isométricos de caparazón y patela entre poblaciones. Las diferencias en el caparazón se asocian con los márgenes anterior, lateral derecho, y posterior. La variación observada podría asociarse a las diferencias ambientales entre localidades. PALABRAS CLAVE. Araña látigo. Conformación. Procrustes. Variación intraespecífica. ABSTRACT. Amblypygi is a small order of arachnids with features similar to spiders. In Colombia, this order has been subject to low attention, the main investigations are focused towards a taxonomic level. Recently, the geometric morphometrics has proven to be an useful tool for determining shape differences in scorpions and spiders. Due to this, we used geometric morphometrics to determine intraspecific variation in three Colombian populations of Phrynus barbadensis. We digitalized 16 anatomical points over the carapace and 15 in patella by combining landmarks and sliding semilandmarks; the coordinates were aligned by generalized Procrustes analysis. Canonical Variates Analysis was implemented with proportions of reclassified groups and MANOVA. We found significant differences of carapace conformation between populations; all specimens were 80% correctly classified. Statistical analyses of variance (ANOVA) found significant differences in carapace and patella isometric size among populations; the main carapace differences occur in anterior, posterior and right margins. The observed variation could be associated with the environmental differences between localities.