|
|
|
| Shell geometric morphometrics in Biomphalaria glabrata (Mollusca: Planorbidae) uninfected and infected with Schistosoma mansoni |
| Cesar Parra1, Jonathan Liria2, 3 * |
| 1Departamento de Vigilancia y Control de Fauna de Moluscos, Coordinación de Zoonosis, Reservorios y Fauna Nociva. Ministerio del Poder Popular para la Salud, Aragua, Venezuela 2Centro de Estudios en Zoología Aplicada. FACYT, Universidad de Carabobo, Carabobo, Venezuela 3Universidad Regional Amazónica IKIAM, km7 vía Muyuna, Napo, Ecuador |
|
|
|
|
Abstract Freshwater planorbid mollusks belonging to the genus Biomphalaria act as intermediate hosts for Schistosoma mansoni, the etiological agent of human intestinal schistosomiasis, in the Neotropical Region. Identification of Biomphalaria spp. are carried out based on morphological characters, and the Schistosoma infection are determined by the presence of cercariae (verified through microscope preparation and mounting). Recently, the geometric morphometrics has proven to be a useful tool for determining shape differences in disease vectors arthropods. Due to this, we used geometric morphometrics to determine Biomphalaria glabrata shell differences (shape and size) between uninfected and infected specimens. We digitalized 12 anatomical points over the shell left side (from umbilicus to the last whorl) by combining type I and II landmarks and sliding semilandmarks; the coordinates were aligned by generalized Procrustes analysis. Principal component analyses were implemented for examining main variation axes, and discriminant analysis for testing group membership significance. We found significant separation between infected and uninfected shell conformation. All specimens were 100% correctly classified. The main differences occur in the peristome. The Kruskal-Wallis test finds significant differences in shell isometric size among infected and uninfected specimens. These findings correspond to other studies of traditional morphometrics, that infected snails showed the reduction in shell size in contrast to those uninfected specimens.
|
|
|
|
Corresponding Authors:
Jonathan Liria
E-mail: jonathan.liria@ikiam.edu.ec
|
|
|
|
| [1] |
Jesus Marugán-Lobón. The Woodcock’s head: Resolving a morphological oddity using geometric morphometrics[J]. Zoological Systematics, 2017, 42(1): 102-107. |
| [2] |
Ming Bai. Geometric morphometrics: Current and future in China[J]. Zoological Systematics, 2017, 42(1): 1-3. |
| [3] |
Norman MacLeod. Morphometrics: History, development methods and prospects[J]. Zoological Systematics, 2017, 42(1): 4-33. |
| [4] |
Ming Bai, Jing Li, Wencheng Wang, Rolf G. Beutel, Benjamin Wipfler, Wangang Liu, Sha Li, Mengna Zhang, Yuanyuan Lu, Xingke Yang. A web based tool to merge geometric morphometric data from multiple characters[J]. Zoological Systematics, 2017, 42(1): 34-45. |
| [5] |
Jean-Pierre Dujardin, Sebastien Dujardin, Dramane Kaba, Soledad Santillán-Guayasamin, Anita G. Villacís, Sitha Piyaselakul, Suchada Sumruayphol, Yudthana Samung, Ronald Morales Vargas. The maximum likelihood identification method applied to insect morphometric data[J]. Zoological Systematics, 2017, 42(1): 46-58. |
| [6] |
Rongrong Li, Hufang Zhang, Shengcai Li, Ming Bai. Geometric morphometric analysis of Eysarcoris guttiger, E. annamita and E. ventralis (Hemiptera: Pentatomidae)[J]. Zoological Systematics, 2017, 42(1): 90-101. |
|
|
|
|
2017, Vol. 42 
