Snakes Flashcards
Snake characteristics
- highest degree of cranial kinesis of any tetrapods
- transparent spectacle covering eye
- large right lung, reduced left
- jacobson/vomeronasal organ (for chemoreception)
Pit organs in snakes
- sensitive infrared receptors
- pit vipers: b/t nostril and eye
- boas and pythons: paired structure along lips
Reproduction with snakes
- paired copulatory organs - hemipenes
- genetic sex determination
Feeding in snakes
- unilateral feeding (right and left bones of upper jaw move alternately)
- have a glottis to breathe while consuming prey
How do snakes kill prey
- constriction
- immobilization with fangs (venom)
Viperid venom
- generally hemolytic, attacks blood - internal bleeding
- also cytolytic, destructs cells
Elapid venom
- generally neurotoxic
- immobilizes prey, permanent damage, suffocates first)
Threats to snake populations
- indiscriminate killing and collecting
- habitat loss and fragmentation
- snake fungal disease
Primitive snakes (order, characteristics)
Order: Scolecophidia
- solid skulls
- fossorial
- primitive eyes - retina only contains rods
Pythons (family and characteristics)
- Family: Pythonidae
- nonvenomous constrictors
- habitat: desert to rain forest
- cloacal spurs
- pit organs
- includes longest extant snake
Burmese python
- introduced into Everglades - invasive
- 30k-300k pythons could be in park
- implicated in severe declines of mammal species
Boas (family and characteristics)
- Family: Boidae
- nonvenomous - vivparous
- vestigal pelvic girdle
- heaviest extant snake
Vipers and pit vipers (family and characteristics)
- Family: Viperidae
- venomous
- viviparous or oviparous
Copperhead (name, range, characteristics)
- Agkistrodon contortrix
- no rattle
- dark cross bands in hourglass pattern
- mostly nocturnal
- south NY
Timber rattlesnake (name, range, characteristics)
- Crotalus horridus
- largest venomous snake in NY
- has ratte
- yellow and dark morphs
- reproduce every 3-4 years
- S NY, along W+S border
Massasauga (name, range, characteristics)
- Sistrurus catenatus
- venomous with rattle
- wetland-dependant
- viviparous
- two spots in NY, one is in Onondaga
Cobras, kraits, sea snakes, death adders and allies (family and characteristics)
- Family: Elapidae
- worlds deadliest snakes
- neurotoxin to paralyze prey
Common snakes (family and characteristics)
- Family: Colubridae
- largest snake family
Northern water snake (name, range, characteristics)
- Nerodia sipedon
- most aquatic NY snake
- permanent freshwater habitats
- All around NY except ADK
Queen snake (name, range, characteristics)
- Regina septemvittata
- moving water with shrubs
- specializes on molted crayfish
- dark tan-black with yellow stripe on lower sides
- 4 spots on W NY
DeKays brown snake (name, range, characteristics)
- Storeria dekayi
- small with keeled scales
- terrestrial and marshy habitats
- scattered everywhere in NY
Red-bellied snake (name, range, characteristics)
- Storeria occipitomaculata
- smallest snake in NY
- 2 color morphs: red/brown
- 3 light spots behind head
- moist forests
- common everywhere in NY
Short-headed garter snake
- Thamnophis brachystoma
- meadows, forest edge
- brown with 3 light stripes
- SW border of NY
Eastern ribbon snake (name, range, characteristics)
- Thamnophis sauritus
- small spot of yellow in front of eye
- long tail
- fairly aquatic but bask in grass
- Scattered through NY but not common
Common garter snake (name, range, characteristics)
- Thamnophis sirtalis
- most widespread snake in NY
- Variable in color
- true viviparity
- everywhere in NY
Smooth green snake (name, range, characteristics)
- Liochlorophis vernalis
- bright green with white belly
- wet grassy areas near forests, lakes, wetlands
- scattered throughout NY
Eastern worm snake (name, range, characteristics)
- Carphophis amoenus
- brown with pink belly, blunt tail
- moist forests with streams
- mostly fossorial
- only in S NY, long island
Eastern racer (name, range, characteristics)
- Coluber constrictor
- black with white chin and dark belly
- does not constrict
- S NY, some in central NY
Ring-necked snake (name, range, characteristics)
- Diadophis punctatus
- yellow/orange belly and neck ring
- mostly nocturnal
- common in central NY mostly, some in S and W NY, almost none north
Eastern rat snake (name, range, characteristics)
- Elaphe alleghaniensis
- longest snake in NY
- black with white checkered belly
- constricts
- mostly S NY, some scattered throughout
Eastern hognose snake (name, range, characteristics)
- Heterodon platirhinos
- flattened, upturned snout
- S NY, some Eastern
Milk snake (name, range, characteristics)
- Lampropeltis triangulum
- red or reddish-brown blotches with black outline
- old fields, farmlands
- everywhere in NY except ADK
