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n.1.(Anat.) A bar of cartilage at the base of the embryonic fins of some fishes. It develops into the metapterygium.
References in periodicals archive ?
The pelvic basipterygium is visible at 9 DPH and begins ossifying at the distal end at approximately 17 DPH.
Conversely, elements of the appendicular skeleton -- such as the posttemporal (a cranial element in the true sense, but appendicular in location), supracleithrum, cleithrum, postcleithrum, scapula, coracoid and basipterygium -- were sometimes left in cured products.
The basipterygium and coracoid are the least abundant of all identified Gadidae elements, but they are extremely fragile.