Comparing shell size and shape with canonical variate analysis of sympatric Biomphalaria species within Lake Albert and Lake Victoria, Uganda

Andrus, Peter S; Stothard, J Russell; Kabatereine, Narcis B; Wade, Christopher M

Abstract

The Great African Lakes in Uganda (Lake Albert and Lake Victoria) are known habitats to several sympatric species of Biomphalaria, intermediate snail hosts of the human parasite Schistosoma mansoni. However, accurate identification of snails by morphology alone can be problematic, highlighting a need for robust, on-site identification methods, since only certain species have important roles in parasite transmission. This study investigates the conchological variation within Biomphalaria species collected from these two Great East African Lakes. We compared the shell morphologies of Biomphalaria species using landmark-based morphometric techniques and were able to distinguish Biomphalaria species through canonical variate analysis (CVA) of the apical and apertural shell angles. After identification with molecular methods, three Biomphalaria species (B. pfeifferi, B. stanleyi, and B. sudanica), with heterogenous occurrences along the shoreline, were identified at Lake Albert that could be differentiated from one another using CVA of apical and apertural datasets; by contrast, a single Biomphalaria species was identified at Lake Victoria (B. choanomphala). When snails from both lakes were compared together, CVA was able to differentiate all four species using the apical dataset but not the apertural dataset. Of the Biomphalaria species identified, ecological phenotypic variation was only found in B. choanomphala, which exhibited two distinct ecological morphotypes. Furthermore, these two B. choanomphala morphotypes from Lake Victoria overlapped upon analysis of the apical dataset, yet were clearly separated upon analysis of the apertural dataset. Our study demonstrates that landmark-based morphometrics could play a future role in distinguishing sympatric Biomphalaria species in Uganda.

• Journal Article Type: Article
• Acceptance Date: Apr 17, 2023
• Online Publication Date: Jul 21, 2023
• Publication Date: 2023-11
• Deposit Date: Jul 25, 2023
• Publicly Available Date: Jul 22, 2024
• Journal: Zoological Journal of the Linnean Society
• Print ISSN: 0024-4082
• Electronic ISSN: 1096-3642
• Publisher: Oxford University Press
• Peer Reviewed: Peer Reviewed
• Volume: 199
• Issue: 3
• Pages: 713-722
• DOI: https://doi.org/10.1093/zoolinnean/zlad052
• Keywords: Gastropoda, Planorbidae, conchology, morphometrics, schistosomiasis
• Public URL: https://nottingham-repository.worktribe.com/output/23475704
• Publisher URL: https://academic.oup.com/zoolinnean/article-abstract/199/3/713/7227518?redirectedFrom=fulltext
• Additional Information: This is a pre-copyedited, author-produced version of an article accepted for publication in Zoological Journal of the Linnean society following peer review. The version of record Peter S Andrus, J Russell Stothard, Narcis B Kabatereine, Christopher M Wade, Comparing shell size and shape with canonical variate analysis of sympatric Biomphalaria species within Lake Albert and Lake Victoria, Uganda, Zoological Journal of the Linnean Society, Volume 199, Issue 3, November 2023, Pages 713–722, is available online at: https://doi.org/10.1093/zoolinnean/zlad052