The Shell evolution of the hydrocenidae of Malaysian Borneo

Bin Khalik, M.Z. (2021)

Doctoral Thesis

The thesis is about the study of shell evolution of the Hydrocenidae of the genus Georissa. This thesis started with a general overview on the evolutionary process of animals due to ecological changes. This study has revealed that the Bornean Georissa are more diverse than previously anticipated. I did the taxonomic revision of the genus Georissa, and discussed the morphological features, phylogenetic relationships, and the biogeographic distribution of the genus in Malaysian Borneo. Also, I studied the shell character evolution of the Bornean Georissa in a phylogenetic framework. Based on the phylogeny, I found convergence in the formation of scales. Additionally, I discussed the differentiation of size and coloration of the Bornean Georissa in dependence on different habitats.

• Hydrocenidae
• Georissa
• Landsnail
• Limestone
• Systematics
• Morphological variation
• Evolution

• All authors: Bin Khalik, M.Z.
• Supervisor: Schilthuizen, M.
• Co-supervisor: Haase, M.
• Committee: Wezel, G.P. van; Welzen, P.C. van; Voogd, N.J. de; Das, I.; Greve, C.
• Qualification: Doctor (dr.)
• Awarding Institution: Institute of Biology Leiden (IBL), Faculty of Science, Leiden University
• Date: 2021-10-06
• Sponsorship: Ministry of Education, Malaysia and Universiti Malaysia Sarawak, Malaysia