Diversity and evolution of color patterns in the goatfishes (Syngnathiformes, Mullidae)

Goatfishes (Mullidae) are coastal tropical and sub-tropical reef fishes distributed worldwide with some species encountered in temperate waters. Goatfishes belong to the Syngnathiform order and include 98 species grouped in 6 genera: Mullus, Upeneus, Upeneichthys, Mulloidichthys, Pseudupeneus and Parupeneus. Beyond the synapomorphic hyoid barbels, this fish family does not look hyper diverse
regarding the diversity of body forms but species differ largely by their colour patterns. Along this study, we aim to test if the diversity (or disparity) of these colour patterns evolved randomly or is explained by different factors. To do so, we compiled data on colour patterns in 80 species by coding the presence/absence of specific marking (e.g. vertical strips, horizontal bars…) on the three main body regions: head, trunk and caudal region (peduncle and fin). The variation of this multivariate dataset was then summarized and visualized using multiple correspondence analysis (MCA). In parallel, we collected on FishBase.org ratios describing head length and body depth, two ecologically relevant morphological traits. First, disparity analyses revealed that genera or species assemblages
from different geographical areas do not greatly differ in the disparity levels of colour patterns and trophic morphology. Only the assemblage of goatfishes from Central Pacific shows a higher level of disparity. Second, partial least squares analyses demonstrate strong correlations between body morphology and colour patterns within every genus and geographical area. These preliminary data certainly support that evolution of colour patterns in goatfishes is not random. External factors such as ecology and/or internal factors such as developmental modularity could drive this pattern of disparification, and will be tested in a future phylogenetic framework.