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

D

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

K

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

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

PERMIAN - 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

Q

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

U

W

Xeric - term used to describe dry environments

Xiphiplastra - the rearmost pair of plastral bones

Y

Z