Fabio C. Ruaza, Miraluna L. Herrera, Romell A. Seronay


A total of 877 individuals of Canarium urceus urceus were collected, measured and evaluated for their morphological attributes in the four (4) sites in Caraga Region: Lianga and Cortes Surigao del Sur; Nasipit, Agusan del Norte and Claver, Surigao del Norte. The shells were morphometrically measures in terms of its shell length (SL), body whorl length (BWL), shell width (SW), shell depth (SD), shell outer lip thickness (SOLT), aperture length (AL), operculum width (OW) and operculum length (OL). The morphometric comparison in different sites detected significant differences in all shell characters across sampling sites. The Principal Component Analysis (PCA) revealed that the most classified characters are the BWL, AL and SL across sampling sites. The most classified characters for male, female and imposex are the OW and SW according to canonical discriminate analysis (CDA). The operculum of imposex is much wider compared to female and male. However, the male gastropod operculum is wider compared to a normal female. In terms of SW of the gastropod, the females have much wider SW and globular than males that are slender in shape.


canarium urceus urceus, morphometry, multivariate analysis

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