Life: The Excitement of Biology 4(4) 272 Geometric Morphometrics Sexual Dimorphism in Three Forensically- Important Species of Blow Fly (Diptera: Calliphoridae) 1 José Antonio Nuñez-Rodríguez 2 and Jonathan Liria 3 Abstract: Forensic entomologists use adult and immature (larvae) insect specimens for estimating the minimum postmortem interval. Traditionally, this insect identification uses external morphology and/or molecular techniques. Additional tools like Geometric Morphometrics (GM) based on wing shape, could be used as a complement for traditional taxonomic species recognition. Recently, evolutionary studies have been focused on the phenotypic quantification for Sexual Shape Dimorphism (SShD). However, in forensically important species of blow flies, sexual variation studies are scarce. For this reason, GM was used to describe wing sexual dimorphism (size and shape) in three Calliphoridae species. Significant differences in wing size between females and males were found; the wing females were larger than those of males. The SShD variation occurs at the intersection between the radius R1 and wing margin, the intersection between the radius R2+3 and wing margin, the intersection between anal vein and CuA1, the intersection between media and radial-medial, and the intersection between the radius R4+5 and transversal radio-medial. Our study represents a contribution for SShD description in three blowfly species of forensic importance, and the morphometrics results corroborate the relevance for taxonomic purposes. We also suggest future investigations that correlated shape and size in sexual dimorphism with environmental factors such as substrate type, and laboratory/sylvatic populations, among others. Key Words: Geometric morphometric sexual dimorphism, wing, shape, size, Diptera, Calliphoridae, Chrysomyinae, Lucilinae Introduction In determinig the minimum postmortem interval (PMI), forensic entomologists use blowflies (Diptera: Calliphoridae) and other insects associated with body corposes (Bonacci et al. 2009, González et al. 2011, Nuñez et al. 2016). Habitually, blowfly species identification comprises taxonomic dichotomous keys for adults (Carvalho and Mello-Patiu 2008, Amat et al. 2008, Solano and Ramírez 2015) or immature stages (Florez et al. 2009, Szpila et al. 2013), to provide reliable information to reconstruct the event involving the perpetrator in court 1 Submitted on April 6, 2017. Accepted on April 14, 2017. Last revisions received on April 16, 2017. 2 Departamento de Ciencias Morfológicas y Forenses, Escuela de Ciencias Biomédicas y Tecnológicas, Facultad de Ciencias de la Salud, Universidad de Carabobo, Valencia, Venezuela. E- mail: joannuro@gmail.com 3 Centro de Estudios en Zoología Aplicada, Universidad de Carabobo, Valencia, Venezuela. Current address: Universidad Regional Amazónica Ikiam, Napo, Ecuador. Corresponding author: jonathan.liria@gmail.com DOI: 10.9784/LEB4(4)NunezRodriguez.01 Electronically available on April 23, 2017. Mailed on April 20, 2017.