Development of Branchiostoma (Amphioxus) is indirect involving a larval stage. Early embryology of Branchiostoma is simple. Therefore, the transformation of egg, which having less yolk, into a complex and differentiated animal is far easier to follow than in any other vertebrate. The early development of Branchiostoma (Amphioxus) is of great phylogenetic significance because it resembles with those of invertebrates like [...]
In this article we will discuss about the external morphology of branchiostoma with the help of suitable diagrams. Shape, Size and Colour: Branchiostoma is about 3.5 to 6.0 cm in length. The body is slender, somewhat translucent, superficially fish-like, laterally compressed and pointed at both ends, hence, the name lancelet. The anterior two-thirds of the body is roughly triangular in [...]
Digestive system consists of an alimentary canal and digestive glands. Alimentary Canal: The alimentary canal is a straight tube from mouth to anus. It is lined by ciliated epithelium. It is divisible into mouth, buccal cavity, pharynx, oesophagus and intestine opening by an anus. 1. Mouth: Mouth lies anteroventrally beneath the rostrum. It is a large oval aperture bordered by [...]