Bonnetina

Bonnetina is a genus of spiders in the Theraphosidae family. It was first described in 2000. As of 2017, it contains 9 species. Bonnetina comprises the following species: Tarantula morphology tends to be excessively homoplastic, which has led to many misidentifications in their phylogenetic analysis. Ortiz, Francke, and Bond conducted a study on the genus Bonnetina, whose members exhibited remarkable heterogeneity to the point that their monophyly was questioned. Additionally, previous attempts at pinpointing the phylogenetic position of Bonnetina were arguably unsuccessful. Their study aimed to address these two issues, as well as create a timeline in the evolution of Bonnetina, and determine the reliability of tarantula classification based on morphology. Due to known issues with homoplasy among tarantulas, they planned to tackle these issues with a molecular approach. They sampled DNA from numerous taxa, and sequenced five nuclear markers and one mitochondrial marker. The data were analyzed using several different models, such as maximum likelihood estimates and Bayesian methods. As a result of their study, they concluded that Bonnetina was indeed monophyletic, with the exception of Bonnetina juxtantricola. The last common ancestor of all tarantulas was about 92 million years ago, with Bonnetina diverging from its sister taxa about 19 million years ago. Most importantly, they confirmed that nearly all morphological traits within the genus Bonnetina were homoplastic. Only sexual features were observed to not be homoplastic, suggesting that sexual selection may have been a driving force in the divergence of tarantulas.