Histological examinations of facial glands in Saccopteryx bilineata (Chiroptera, Emballonuridae), and their potential use in territorial marking

Caspers B, Wibbelt G, Voigt CC. Histological examinations of facial glands in Saccopteryx bilineata (Chiroptera, Emballonuridae), and their potential use in territorial marking. ZOOMORPHOLOGY. 2009;128(1):37-43.Scent marking is widespread among individuals of Mammalia species, especially in resource defence social systems. Apart from urine and faeces that are used for claiming resource ownership, specialised scent glands are the main source of secretions in scent marking individuals. Most previous studies have described secretory epithelia macroscopically, since many glands are conspicuous. But macroscopically inconspicuous scent glands or morphological structures might then be overlooked. In Saccopteryx bilineata (greater sac-winged bat), behavioural observations suggest that both sexes have, apart from the conspicuous gular glands of males, specialised facial glands to display territorial marking. We investigated the facial glands of two males and one female S. bilineata histologically and found, first, that both sexes possess a bilateral symmetrically intermandibular gland, which is composed of a bed of modified apocrine sudoriferous cells. Second, we found lip glands consisting of modified apocrine sudoriferous cell units with pigmented ducts around the upper and the lower lip. Both gland types are probably involved during territorial marking

Odour-based species recognition in two sympatric species of sac-winged bats (Saccopteryx bilineata, S-leptura): combining chemical analyses, behavioural observations and odour preference tests

Caspers B, Schroeder FC, Franke S, Streich WJ, Voigt CC. Odour-based species recognition in two sympatric species of sac-winged bats (Saccopteryx bilineata, S-leptura): combining chemical analyses, behavioural observations and odour preference tests. BEHAVIORAL ECOLOGY AND SOCIOBIOLOGY. 2009;63(5):741-749.Combining chemical analysis and odour preference tests, we asked whether two closely related sympatric species of sac-winged bats use odour for species recognition. Males of the two sister species Saccopteryx bilineata and Saccopteryx leptura have pouches containing an odoriferous liquid in their antebrachial wing membrane, which is used in S. bilineata during courtship displays. Although both species occasionally share the same daytime roosts and are morphologically similar, there is no evidence for interbreeding. We compared the production and composition of the wing sac odorant in male S. leptura and S. bilineata and performed odour preference tests with female S. bilineata. Similar to male S. bilineata, male S. leptura cleansed and refilled their wing sacs with secretions, but they spent more time each day in doing so than male S. bilineata. Chemical analysis by gas chromatography and mass spectrometry revealed that male Saccopteryx carried species-specific scents in their wing sacs. Binary choice tests confirmed that female S. bilineata preferred the wing sac scents of male S. bilineata to those of the sister species, suggesting that the species specificity of male wing sac scents maintain the pre-mating isolation barrier between these closely related species