ReseaRch aRticles A possible case of mimicry involving a heteropteran insect and an anuran tadpole MARCO AURÉLIO P. HORTA 1 , ALAN LANE DE MELO 2 and JAIME BERTOLUCI 3,4 1 Fundação Oswaldo Cruz, Escola Nacional de Saúde Pública, Rua Leopoldo Bulhões, 1480, Manguinhos, 21041-210, Rio de Janeiro, RJ, Brazil. 2 Laboratório de Taxonomia e Biologia de Invertebrados, Departamento de Parasitologia, Universidade Federal de Minas Gerais, Brazil. 3 Departamento de Ciências Biológicas, Escola Superior de Agricultura “Luiz de Queiroz”, Universidade de São Paulo, Av. Pádua Dias, 11, 13418-900, Piracicaba, SP, Brazil. 4 Corresponding author: bertoluc@esalq.usp.br 4 Number 114 - Herpetological Bulletin [2010] ABSTRACT - We report on the occurrence of similar aposematic colour pattern between two phylogeneticaly unrelated aquatic organisms, an insect and a tadpole. The limnocorid Heteroptera Limnocoris porphyrus and tadpoles of the hylid frog Scinax machadoi are found in sympatry and syntopy in several streams in the Serra do Cipó, a pristine area located in the Espinhaço Range, Minas Gerais state, southeastern Brazil. The similarity between these two organisms makes it dificult to distinguish them at irst sight. We suggest that they are possibly part of a process of Müllerian mimicry, but we recognize an evaluation of palatability and population size estimates are needed to ascertain our suggestions. A POSEMATISM, the use of bright colour patterns by noxious animals to deter predators, is a well-documented phenomenon in nature (Mallet & Joron, 1999; Joron, 2003; Wüster et al., 2004). In the evolutionary process of mimicry a species evolves coloration similar to another species. In Batesian mimicry a palatable prey species mimics the appearance of a noxious species reducing its risk of being attacked. In Müllerian mimicry, two aposematic organisms conform to the same aposematic signal to their mutual beneit (Joron, 2003). Predators learn to avoid brightly patterned or otherwise conspicuous noxious prey items more rapidly than cryptic prey items (Guilford, 1986; Rowe & Guilford, 2000), and consequently aposematism and/or Batesian mimicry have usually been inferred in cases where the presumed mimic matches a brightly patterned model. Most of aposematism theory is based on two-species interactions, with one noxious prey (the signaller) and one predator (the receiver) (Wüster et al., 2004). Many organisms present bright or conspicuous patterns of colour and observations under experimental conditions simulating naive avian predators have shown how these species are involved in so-called mimicry rings (Mallet & Joron, 1999; Joron, 2003). Elucidating conditions favouring co-evolution in mimicry is one of the oldest problems in Evolutionary Biology (Gilbert, 1983). This work presents a case of two sympatric aquatic species, an insect and a frog tadpole. The bright colour pattern of the insect and the tadpole is found in their early stages of its development. The Serra do Espinhaço is a mountain range located in the states of Minas Gerais and Bahia, Brazil, and observations have been made at two localities at 95 km in a straight line from each other. In Serra do Cipó (19º12’-19º20’ S, 43º30’-43º40’ W), a high altitudinal area covered by savanna vegetation, xeric habitats and an abundance of sclerophylous plants. Above 900 m ASL campo rupestre vegetation dominates with fragments of high altitude grassland vegetation (Ribeiro et al., 1990). Serra do Caraça (20º05’S, 43º28’W)