System Glossary
 Glossary Search for monospondylous-diplospondylous transition (Search Options)

Definition of Term

monospondylous-diplospondylous transition
(English) The position on the ventral column where monospondylous centra end and diplospondylous centra begin. In lateral view the transition often appears as an abrupt decrease in length of the diplospondylous centrum, but this can be obscure in various sharks with very numerous, very short centra. Often a centrum of intermediate length appears between a long monospondylous centrum and a short diplospondylous centrum. In a few sharks there is a few stutter zone of alternating long and short centra that marks the transition. Also, the basidorsals and basiventrals have foramina for the spinal nerves on every other vertebra, rather than on each vertebra as in monospondylous vertebrae. The transition from long to short centra is generally coordinated with the transition of vertebrae with free ribs and no haemal arches to those without ribs and with haemal arches. However, in some sharks the two transitions can be anterior or posterior to each other.

Other Search Engines

European Environment Agency Glossary of the European Environmental Agency
Wikipedia The Free Encyclopedia
Encyclopedia Britannica Highly authoritative source
EPA Terms Glossary of the U.S. Environmental Protection Agency
Google Search The largest Internet Search Engine
Google Image Search for Images related to the term
eENVplus Thesaurus Thesaurus gathering glossaries for biodiversity, environment and biogeography
A-Z Biodiversity Terms Glossary providing definitions of terms, areas and acronyms related to biodiversity, commonly used, internationally recognized where possible, well referenced, and derived from legitimate sources
Glossary Index: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Back to Search
Back to Top