From the IUCN Red List Species Account:

Range Description

This species is known only from north-central Oaxaca in southern Mexico, at 2,300 m asl. It is known from one threat-defined location and its extent of occurrence (EOO) is 4,106 km².

Habitat and Ecology

This species inhabits pine and pine-oak forests at high elevations. It is terrestrial and found beneath logs and rocks. It is presumed to reproduce by direct development.

Population

It was known to be common to very common 30 years ago (in the 1970s), but is now rarely found (D. Wake pers. comm. 2005). An observation of this species was recorded in the town of Santa Maria Huitepec in 2009, and locals in Ayulta reported seeing it on a regular basis (Lamoreux et al. 2015). Due to ongoing decline in the extent and quality of habitat, the population is suspected to be decreasing.

Population Trend

decreasing

Major Threats

Habitat loss due to small-holder agricultural activities is a threat to this species. However it does not appear to be at a scale large enough to completely explain the previous observed declines within the population.

Conservation Actions

Conservation Actions
This species is not known from any protected areas. 

Conservation Needed
Habitat protection is required.

Research Needed
Research is needed to determine the reason for the apparent population declines in suitable habitat.

Red List Status

Vulnerable (VU)

Rationale

Listed as Endangered because its extent of occurrence (EOO) is 4,106 km², it occurs in one threat-defined location, and there is ongoing decline in the extent and quality of its' habitat in Oaxaca.

Taxonomic Notes

This species was previously within the genus Pseudoeurycea but has recently been moved to Isthmura (Dubois and Raffaëlli 2012). It was resurrected from synonymy with Isthmura bellii (as Pseudoeurycea bellii in Parra-Olea et al. 2005).

Citation

IUCN SSC Amphibian Specialist Group 2018. Isthmura boneti. The IUCN Red List of Threatened Species 2018: e.T61906A53989244. http://dx.doi.org/10.2305/IUCN.UK.2018-1.RLTS.T61906A53989244.en