The forelimb swellings of Pygoderma bilabiatum (Chiroptera: Phyllostomidae) / The forelimb swellings of Pygoderma bilabiatum (Chiroptera: Phyllostomidae)

ABSTRACT

Pygoderma bilabiatum is a medium-sized short-faced stenodermatine bat (Chiroptera Phyllostomidae) with prominent doughnut-shaped glandular tissue masses surrounding the eyes, among other distinctive characters. In this paper, we describe gross external morphology of newly discovered swellings of Pygoderma, probably enclosing glandular tissue found in the dorsal forelimbs of certain male individuals and discuss intra-specific variation in their development. All male individuals observed with large forelimb swellings also had largely developed periorbital and submandibular glands thus suggesting that all male skin glands/swellings in this species develop more or less concordantly. The episodic chronological distribution of male Pygoderma specimens with developed forelimb swellings suggests a relationship with reproductive cycles.

RESUMO

Pygoderma bilabiatum is a medium-sized short-faced stenodermatine bat (Chiroptera Phyllostomidae) with prominent doughnut-shaped glandular tissue masses surrounding the eyes, among other distinctive characters. In this paper, we describe gross external morphology of newly discovered swellings of Pygoderma, probably enclosing glandular tissue found in the dorsal forelimbs of certain male individuals and discuss intra-specific variation in their development. All male individuals observed with large forelimb swellings also had largely developed periorbital and submandibular glands thus suggesting that all male skin glands/swellings in this species develop more or less concordantly. The episodic chronological distribution of male Pygoderma specimens with developed forelimb swellings suggests a relationship with reproductive cycles.