Double mutualism involving Melocactus (Cactaceae) and lizards in the Brazilian Caatinga: Another isolated case or is it an established interaction?

• Published in: Austral ecology Vol. 49; no. 2
• Main Authors: Bezerra‐Silva, Alexsandro, Gomes, Vanessa Gabrielle Nóbrega, Albuquerque‐Lima, Sinzinando, Nadia, Tarcila Lima, Machado, Isabel Cristina, Silveira Funch, Ligia
• Format: Journal Article
• Language: English
• Published: Richmond Blackwell Publishing Ltd 01.02.2024
• Subjects: arid environments; Breeding success; Coevolution; Dispersion; dry forest; Dry forests; floral and lizards' traits; floral resources; Flowers; Lizards; Melocactus; Mutualism; Nectar; Pollen; Pollinators; Reproduction; saurochory; saurophily; Seeds; Stigmas (botany); Tropical forests; Tropidurus; Brazil
• ISSN: 1442-9985; 1442-9993
• DOI: 10.1111/aec.13494

This work discusses a fascinating ecological relationship, in which the lizard Tropidurus cocorobensis and the cactus Melocactus violaceus engage in a double mutualism. In this interaction, observed in a Caatinga, a dry tropical forest in Northeastern Brazil, T. cocorobensis feed on the nectar and pollen of M. violaceus, transferring the grains to the stigmas of another flower, acting as a potential pollinator. Additionally, the lizards consume fruits of M. violaceus, helping to disperse the seeds. The concentrated nectar of M. violaceus attracts lizards, and the morphological compatibility between the small pink flowers and the size of T. cocorobensis is important to this double mutualism. The findings mentioned here highlight the importance of Tropidurus lizards in the reproductive success of Melocactus species and provide insights into the coevolution of these species in a seasonal and resource‐scarce environment, like the Caatinga. Resumo Este trabalho discute uma fascinante relação ecológica na Caatinga, na qual o lagarto Tropidurus cocorobensis e o cacto Melocactus violaceus se envolvem em um duplo mutualismo. Nessa interação, observada na Caatinga, uma floresta seca no Nordeste do Brasil, T. cocorobensis se alimenta do néctar e do pólen de M. violaceus, transferindo os grãos para os estigmas de outra flor, atuando como potencial polinizador. Além disso, os lagartos consomem frutos de M. violaceus, auxiliando também na dispersão das sementes. O néctar concentrado de M. violaceus atrai os lagartos, e a compatibilidade morfológica entre as pequenas flores rosadas e o tamanho de T. cocorobensis é crucial para esse duplo mutualismo. As descobertas aqui mencionadas destacam a importância dos lagartos Tropidurus no sucesso reprodutivo de espécies de Melocactus e fornecem informações sobre a coevolução dessas espécies em ambientes sazonais e com escassez de recursos, como a Caatinga. Tropidurus cocorobensis individual on the cephalium surface of Melocactus violaceus.