Allometry and morphological integration shape the chemical detection system in Liolaemus lizards (Squamata, Iguania)

RUIZ-MONACHESI, MARIO R.; ABDALA C S; CRUZ FELIX

ZOOLOGISCHER ANZEIGER

ELSEVIER GMBH

Año: 2022 vol. 299 p. 221 - 233

0044-5231

The chemosensory system in tetrapods consists of glands that emit chemical signals and specialized organs thatcapture these signals. Lizards mostly depend on this chemosensory modality and different relationships havebeen suggested among components of their chemical detection systems; the vomeronasal organ (VNO), palatalopenings (PO) and tongue morphology (TM), as well as epidermal glands and their secretions. In this study, weused phylogenetic geometric morphometrics to examine shape variation in the VNO, PO and TM of 20 species ofLiolaemus lizards. First, we tested whether phylogeny, allometry or diet type influenced their shape. Second, wetested an integration hypothesis between the shapes of the VNO, palatal opening and tongue, as well as, theirassociation with the number of precloacal epidermal glands (PEG). Third, we tested the relationship between theevolutionary change rates of trait shape. Results showed a weak phylogenetic effect on shapes and an allometryeffect on the shape of PO. The diet type did not affect the shape of these traits as well as, the number of precloacalepidermal glands. The tongue shape showed significant integration patterns with both the shape of VNO and PO.A faster evolutionary rate change was observed for PEG; VNO and PO showed similar medium rates and TMshowed the slowest evolutionary rate. Our results suggest that allometry and different morphological integrationpatterns may affect the chemosensory system in studied species. The integration patterns among the shapes of thetongue, the VNO and the PO support the assumed association of the chemical detection system components inLiolaemus lizards.