Sexually dimorphic skin glands in the invasive species Lithobates catesbeianus (Anura: Ranidae)

Abstract Males of most amphibian species possess specialized cutaneous glands, known as sexually dimorphic skin glands (SDSGs). SDSGs are usually clustered in specific body regions and externally visible, but some cases, external differences between males females can be slight or absent, the occurrence only disclosed by histological studies. Chemical signals produced markedly affect behaviour reproduction, therefore their occurrence, features, location could provide information on potential mechanisms intraspecific communication a particular species. In present study, we perform light microscope (both histochemical), scanning electron studies samples from male female adult specimens invasive bullfrog Lithobates catesbeianus , covering several that hold SDSGs. Most areas analysed showed ordinary granular mucous despite remarkable sexual dimorphism observed. By contrast, nuptial pads contained exclusively were hypertrophied (SMGs), closely resembling breeding described other anurans. Our histochemical study revealed these SMGs contain heterogeneous populations secretory cells, possibly involved pheromone production. We discuss characteristics found L. well surface specialization (achieved microscopy) role chemical this