ヤミノニシキガイ 2 型の特徴 : 3. 年齢と成長

概要

論文の詳細を見る
To clarify the taxonomic status of two forms (Awajichihiro and Yaminonishiki) of Hirase's scallop Volachlamys hirasei, age and growth were examined as the third report of series studies. Circular annuli on the shell surface were used as an age character. Seasonal changes of marginal growth rate (MGR) of the two forms suggested that annulus formation occurs once a year, from March to June ; the annuli are regarded as winter rings. Relationship between shell length at age t (L_t) and that at age t+1 (L_<t+1>) corresponded well with a linear regression of Walford growth transformation in the both forms. The von Bertalanffy growth formulae led from parameters of the transformation were as follows : Awajichihiro form : L_t=56.95 (1-e^<-0.244(t+0.404)>) Yaminonishiki form : L_t=61.64 (1-e^<-0.216(t+0.378)>) Parameters of the Walford growth transformation between the two forms indicated significant difference at the L_t coefficient which indicated growth rapidity, the Yaminonishiki form growing more rapidly than the Awajichihiro form. This might be caused by the conchological differentiation between the two forms.
日本貝類学会の論文
1998-03-31