Crotalus willardi obscurus

New Mexico Ridge-nosed Rattlesnake

FWS Focus

Overview

This is a small (maximum length 66 cm) montane species that is usually pale gray to gray-brown and does not have prominent facial markings. The back is marked with pale crossbars lined with darker coloration along the front and back edges. The underside is cream to white with occasional mottling of grayish to reddish brown.Young have dark gray/black or light yellow tails.

Scientific Name

Crotalus willardi obscurus
Common Name
New Mexico ridge-nosed rattlesnake
New Mexico ridgenose rattlesnake
New Mexican ridge-nosed rattlesnake
Animas ridge-nosed rattlesnake
FWS Category
Reptiles
Kingdom

Location in Taxonomic Tree

Identification Numbers

TSN:

Geography

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Timeline

Explore the information available for this taxon's timeline. You can select an event on the timeline to view more information, or cycle through the content available in the carousel below.

5 Items

Critical Habitat

Critical Habitat

Listing

Five Year Review

Five Year Review

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Critical Habitat

May 26, 1977

May 26, 1977 Critical Habitat
Proposed Endangered Status and Critical Habitat for New Mexico Ridge-Nosed Rattlesnake; 42 FR 27007…
  • Publication type: Proposed
Item 1

Critical Habitat

Aug 4, 1978

Aug 4, 1978 Critical Habitat
Listing of the New Mexican Ridge-nosed Rattlesnake as a Threatened Species with Critical Habitat
  • Publication type: Final
Item 2

Listing

Aug 4, 1978

Aug 4, 1978 Listing (Threatened)
Listing of the New Mexican Ridge-nosed Rattlesnake as a Threatened Species with Critical Habitat
  • Publication type: Final
Item 3

Five Year Review

Apr 23, 2007

Apr 23, 2007 Five Year Review (Information Solicitation)
5-Year Reviews of 24 Southwestern Species
  • Publication type: Notice
Item 4

Five Year Review

May 31, 2018

May 31, 2018 Five Year Review (Information Solicitation)
Initiation of 5-Year Status Reviews of 38 Species in the Southwest Region (Arizona, New Mexico, Okl…
  • Publication type: Notice
Item 5