A SYSTEMIC SECONDARY VESSEL SYSTEM IS PRESENT IN THE TELEOST FISH TANDANUS-TANDANUS AND ABSENT IN THE ELASMOBRANCHS CARCHARHINUS-MELANOPTERUS AND RHINOBUTOS-TYPUS AND IN THE DIPNOAN NEOCERATODUS-FORSTERI

Citation
Lk. Chopin et al., A SYSTEMIC SECONDARY VESSEL SYSTEM IS PRESENT IN THE TELEOST FISH TANDANUS-TANDANUS AND ABSENT IN THE ELASMOBRANCHS CARCHARHINUS-MELANOPTERUS AND RHINOBUTOS-TYPUS AND IN THE DIPNOAN NEOCERATODUS-FORSTERI, Journal of zoology, 246, 1998, pp. 105-110
Citations number
23
Categorie Soggetti
Zoology
Journal title
ISSN journal
09528369
Volume
246
Year of publication
1998
Part
1
Pages
105 - 110
Database
ISI
SICI code
0952-8369(1998)246:<105:ASSVSI>2.0.ZU;2-N
Abstract
A system of secondary vessels emerging from the primary vessels as num erous coiled capillaries has been described in numerous teleost and ho lost fishes. The systemic secondary vessels of the teleost Tandanus ta ndanus are typical of this system and are described in this study. The existence of a secondary vessel system has been postulated in the ela smobranch group. No secondary vessel origins, as seen in the teleosts, are present in the elasmobranchs Rhinobatos typus and Carcharhinus me lanopterus. Vessels with a similar distribution to secondary arteries are observed but these are venous rather than arterial in nature and d o not connect with the primary arteries. Like the secondary veins in t eleosts, the cutaneous veins in R. typus contain blood with a low haem atocrit. There is no morphological evidence for a secondary vessel sys tem in the dipnoan Neoceratodus forsteri.