Pr. C1 BALANOGLOSSUS(Acornworm)

 

Phylum: Chordata  

Class: Enteropneusta

Family: ptychoderidae

Genus: Blanoglossus

 

Description:  

It is a protochordata and it is commonly called acornworm. It is a marine and burrowing animal. Cylindrical in shape, growing to a length of 10 to 50 cm. The body consists of three regions, namely an anterior proboscis, a collar and a posterior long trunk. Proboscis is conical in shape and used for burrowing. Collar connects the proboscis with the trunk. Trunk is long and transversely wrinkled. It consists of three regions, namely an anterior branchio genital region, a middle hepatic region and a posterior abdominal region. Branchial region contains two rows of branchial apertures. Genital region contains gonads.  Hepatic region contains hepatic caeca. Mouth is located at the anterior end of the collar.  Anus is located at the posterior end of the abdomen.  The notochord is represented by an outgrowth of the buccal cavity called buccal diverticulum.  Sexes are separate and fertilization is external.  Development is indirect and it includes a larva called tornaria larva.  Connecting link between invertebrates and chordates.

IUCN: Not evaluated