Turtle glossary

(Based on : http://www.chelydra.org/turtle_dictionary.html)


Abdominal scutes - the third rearmost pair of plastral scutes
Anal scutes - the rearmost pair of plastral scutes
Axillary scutes - the small plastral scutes opposite the armpits


Beak - the horny plate covering the jaws
Bridge - part of the shell connecting the carapace and plastron


Carapace - the dorsal part of the shell
Caruncle - the horny tubercle on snout of baby turtles used to break through eggshell ( egg tooth )
Caudial - pertaining to the tail
Central scute - one of large ( usually five ) scutes extending down the midline of carapace
Cloaca - chamber into which the digestive, urinary and reproductive organs empty
Costals - large ( usually four ) scutes running down each side of carapace
CRETACEOUS - a geologic period about 140 to 65 million years ago
Cruro - pertaining to the thigh or leg
Cryptozoic - conducting a hidden or secluded way of life



Endemic - naturally restricted to a particular area
Entoplastron - a single plastral bone occuring between and surrounded by epiplastra and hyoplastra
EOCENE - a geologic period approximately 55 to 35 million years ago
Epiplastron - one of the two anteriormost bones in the plastron
Estivation - state of inactivity during long periods of drought or high temperatures


Fontanelle - an opening present in young turtles skull or shell, filled with maturity


Glottis - closable opening in the floor of the mouth into which the windpipe opens
Gular scutes - the foremost plastral scutes ( paired or single )


Humeral scutes - the second pair of scutes in the turtles plastron
Hyoplastra - the second frontmost pair of plastral bones
Hypoplastra - the second rearmost pair of plastral bones


Inguinal notch - the notch at the rear of bridge from which the hind legs protrude
Inguinal scutes - scutes just in front of the inguinal notch
Intergular scute - a sometimes present small scute which separates the gular scutes


Jurassic - a geological period approximately 185 to 140 million years ago



Lamella - a thin plate made from bone or keratin


Marginal scutes - small scutes around the edge of carapace
Melanism - development of excessive dark pigment
Mesoplastra - in some turtles, plastral bones located between the hyoplastra and hypoplastra
Mesozoic - " Age of Reptiles ", a geologic era containing the Triassic, Jurassic and Cretaceous periods
Miocene - a geologic epoch approximately 20 to 12 million years ago
Monotypic - a taxonomic category, a family with only one genus or only one species


Nominate race- The first-named race of a species, with its scientific name the same as the specific name
Nuchal bone - large bone at the front of the turtles carapace
Nuchal scute - a small scute at the front of the carapace, present in many turtles


Ocellus - a ring - shaped, often with dark center, marking
Oligocene - a geologic epoch approximately 35 to 20 million years ago
Ovipositor - a soft tubular structure extruded from the vent durin oviposition of eggs


Paleocene - a geologic epoch approximately 65 to 55 million years ago
Papilla - a soft elongate protruberance
Pectorial scutes - the third frontmost pair of plastral scutes
Pedicle - a thickened area of bone designed to withstand weight or pressure
Pentadactyly - a condition of having five digits in hand or foot
Permiah - a geologic period approximately 275 to 230 million years ago
Plastron - the lower part of the shell
Pleistocene - a geologic epoch approximately 2 million to 11 thousand years ago
Pliocene - a geologic epoch approximately 12 to 2 million years ago
Postorbital - a scale or other structure behind the eye
Pygal - the rearmost bone in turtles carapace



Rathke's Glants - glants from which some turtles can exude a highly odorous secretion


Seam - the line between two scutes
Serrated - saw - toothed edge
Supracaudal scutes - two rearmost marginal scutes ( sometimes fused in one )
Supramarginal scutes - scutes located between the costals and marginals ( present in Macroclemys )
Sympatric - occupying the same geographic area


Tachycardia - the slowing of heart during turtles dive
Temporal - the sides of the scull behind eyes
Teriary - a geologic period encompassing Paleocene to Pliocene
Tubercle - a small lump
Tuberosity - a large tubercle
Tympanum - a vibrating surface which forms the external ear in turtles
Type - the specimen on which a species is based and named
Type genus - the genus selected as a standard of reference for a family
Type species - the species upon which the description of a genus is based




Xeric - term used to describe dry environments
Xiphiplastra - the rearmost pair of plastral bones