Fauna
Amphibian

San Marcos Salamander

Eurycea nana

San Marcos salamanders spend their entire lives fully underwater, retaining prominent feathery red gills and a finned tail into adulthood. They shelter among dense mats of aquatic vegetation and submerged limestone gravel bathed by constant 22 °C water from the Edwards Aquifer. Confined to a minuscule natural range, these delicate amphibians serve as vital bioindicators for groundwater purity across central Texas.

AquaticEndemicSpring-Dwelling
San Marcos Salamander reference1 / 2
(c) Reid Hardin, some rights reserved (CC BY), uploaded by Reid Hardin · cc-by
—observations
—countries
—peak records
VulnerableConservation statusIUCN Red List categoriesLCNTVUENCREWEXVulnerableRed List categories, explained →
Key facts
Diet & preyAmphipods, Midge Larvae, Freshwater Snails
Predators
  • Largemouth Bass
  • Green Sunfish
  • Crayfish
ThreatsGroundwater pumping, pollution, recreational disruption, and invasive species
HabitatsSpring-fed freshwater lakes, spring outflows, and gravelly stream beds
Life span5–10 years
Classification
  1. FamilyPlethodontidae
  2. SpeciesEurycea nana
Range & activity
Range data is not available yet.
Safe observation
Interaction riskLow
  1. Low
  2. Moderate
  3. High
  4. Very high
Why interaction risk is low
Safe to observe at a normal distance.
What to notice
Look for a tiny reddish-brown body under six centimeters long with conspicuous, bushy red external gills.
Support conservation
Do not touch, handle, or disturb submerged rocks and moss mats where individuals forage and hide.
Responsible observation
  • Viewing Etiquette: Look for them on guided glass-bottom boat tours at Spring Lake to minimize disruption.
  • Habitat Protection: Avoid wading through submerged aquatic moss mats or turning rocks in protected spring runs.
Related species
Help improve the field guideSomething wrong?

Report a name, category, or profile issue for review.

Checking your Fauna account…