IDENTIFICATION: DISTRIBUTION: Thorius arboreus is known to occur along the upper Atlantic slope of Cerro Pelon, Oaxaca between 2170 and 2755 meters elevation. Most specimens have been collected in the immediate vicinity of Hwy. 175.

HABITAT: As it’s name implies, Thorius arboreus is commonly found within the leaf axils of arboreal [...]]]> ARBOREAL MINUTE SALAMANDER
Thorius arboreus – Hanken & Wake 1994

IDENTIFICATION:
DISTRIBUTION:
Thorius arboreus is known to occur along the upper Atlantic slope of Cerro Pelon, Oaxaca between 2170 and 2755 meters elevation. Most specimens have been collected in the immediate vicinity of Hwy. 175.

HABITAT:
As it’s name implies, Thorius arboreus is commonly found within the leaf axils of arboreal bromeliads, both in trees and on the ground, within it’s upper montane cloud forest habitat.
NATURAL HISTORY:
This salamander reproduces by direct developement, like all other species of Thorius. Thorius arboreus is sympatric with Thorius aureus at a locality 2 km north of the Hwy. crest on the top of Cerro Pelon; both Thorius boreas and Thorius macdougalli are found within 1 km of this locality (1 km N of the Hwy. crest of the top of Cerro Pelon), but it appears they do not occur in sympatry with T. arboreus.
TAXONOMY:
TYPE:
Described as Thorius arboreas by Hanken and Wake (1994). Holotype: MVZ 196078. Type locality: 10.9 km (rd.) W La Esperanza, along Hwy. 175, Oaxaca, Mexico, elev. 2060 m. An adult female collected by D. Darda and P. Garvey on 20 November 1983.
PERSONAL NOTES:
I have no experience with this species despite having spent some time at the type locality on Cerro Pelon, Oaxaca.
CONSERVATION STATUS:
REFERENCES:
Hanken, J., Wake, D. B. 1994. Five New Species of Minute Salamanders, Genus Thorius (Caudata: Plethodontidae), from Northern Oaxaca, Mexico. Copeia 1994(3):573-590.
Hanken, J., Wake, D. B., and Freeman, H. L. 1999. Three New Species of Minute Salamanders (Thorius: Plethodontidae) from Guerrero, Mexico, Including the Report of a Novel Dental Polymorphism in Urodeles. Copeia 1999(4):917-931.

IDENTIFICATION: DISTRIBUTION: Thorius aureus is known only from the upper Atlantic slope of Cerro Pelon, Oaxaca at elevations of 2475 to 2930 meters. All collection sites are adjacent to Oaxaca Hwy. 175.

HABITAT: This species inhabits terrestrial microhabitats in both upper cloud forest and montane pine-oak-fir forest. NATURAL HISTORY: This salamander [...]]]> GOLDEN (CERRO PELON) MINUTE SALAMANDER
Thorius aureus – Hanken & Wake 1994

IDENTIFICATION:
DISTRIBUTION:
Thorius aureus is known only from the upper Atlantic slope of Cerro Pelon, Oaxaca at elevations of 2475 to 2930 meters. All collection sites are adjacent to Oaxaca Hwy. 175.

HABITAT:
This species inhabits terrestrial microhabitats in both upper cloud forest and montane pine-oak-fir forest.
NATURAL HISTORY:
This salamander reproduces by direct developement, like all other species of Thorius. It occurs in sympatry with Thorius arboreus at a point 1 km N of it’s type-locality, and with both T. macdougalli and T. boreas at it’s type-locality.
TAXONOMY:
TYPE:
Described as Thorius aureus by Hanken and Wake (1994). Holotype: MVZ 85966. Type locality: 0.7 mi (rd.) E Cerro Pelon from point where road crosses top, Oaxaca, Mexico. An adult female collected by R. W. McDiarmid and R. D. Worthington on 20 January 1969.
PERSONAL NOTES:
I have no experience with this species despite having spent some time at the type locality on Cerro Pelon, Oaxaca.
CONSERVATION STATUS:
REFERENCES:
Hanken, J., and Wake, D. B. 1994. Five New Species of Minute Salamanders, Genus Thorius (Caudata: Plethodontidae), from Northern Oaxaca, Mexico. Copeia 1994(3):573-590.
Hanken, J., Wake, D. B., and Freeman, H. L. 1999. Three New Species of Minute Salamanders (Thorius: Plethodontidae) from Guerrero, Mexico, Including the Report of a Novel Dental Polymorphism in Urodeles. Copeia 1999(4):917-931.

IDENTIFICATION: DISTRIBUTION: Thorius boreas is found in the vicinity of Llano de las Flores, and both north and south of the summit of Cerro Pelon. Elevational distribution from 2850-2950 m.

HABITAT: This terrestrial species inhabits pine-oak-fir forests and their edges at elevations of 2850 to 2950 meters. NATURAL HISTORY: This [...]]]> LLANO DE LAS FLORES MINUTE SALAMANDER
Thorius boreas – Hanken & Wake 1994

IDENTIFICATION:
DISTRIBUTION:
Thorius boreas is found in the vicinity of Llano de las Flores, and both north and south of the summit of Cerro Pelon. Elevational distribution from 2850-2950 m.

HABITAT:
This terrestrial species inhabits pine-oak-fir forests and their edges at elevations of 2850 to 2950 meters.
NATURAL HISTORY:
This terrestrial salamander reproduces by direct developement, like all other species of Thorius. Thorius boreas is found in sympatry with T. macdougalli at both Llano de las Flores, and on the top of Cerro Pelon; at a ravine 1 km N of the point where Hwy. 175 crosses the summit of Cerro Pelon T. boreas occurs with both T. macdougalli and T. aureus. Pseudoeurycea juarezi, P. smithi and P. papenfussi are larger species of salamander that have been found in sympatry with this species.
TAXONOMY:
TYPE:
Described as Thorius boreas by Hanken and Wake (1994). Holotype: MVZ 162202. Type locality: Llano de las Flores, along Hwy. 175, 25-26 km NE Guelatao, Oaxaca, Mexico. An adult male collected by T. J. Papenfuss on 12 August 1975.
PERSONAL NOTES:
In July 2006 I was fortunate to find this species at two sites in the Sierra de Juarez. I flipped a single individual beneath a piece of damp wood at the forested edge of Llano de las Flores, and later that afternoon my friend and I found several specimens beneath deep forest litter and a pile of wet cardboard just a few miles from the Llano. I can’t be sure, but I believe we found T. macdougalli beneath the cardboard as well.
CONSERVATION STATUS:
REFERENCES:
Hanken, J., Wake, D. B. 1994. Five New Species of Minute Salamanders, Genus Thorius (Caudata: Plethodontidae), from Northern Oaxaca, Mexico. Copeia 1994(3):573-590.
Hanken, J., Wake, D. B., and Freeman, H. L. 1999. Three New Species of Minute Salamanders (Thorius: Plethodontidae) from Guerrero, Mexico, Including the Report of a Novel Dental Polymorphism in Urodeles. Copeia 1999(4):917-931.

IDENTIFICATION: DISTRIBUTION: HABITAT: NATURAL HISTORY: TAXONOMY: TYPE: PERSONAL NOTES: CONSERVATION STATUS: REFERENCES:

IDENTIFICATION: DISTRIBUTION: Thorius grandis is endemic to the mountains northeast of Atoyac de Alvarez, Guerrero. Most localities are from the slopes of Cerro Teotepec, although one record exists for Cerro Toro Muerto (about 10 air km northwest of Cerro Teotepec). On the Atoyac/Milpillas highway most records exist between [...]]]> GRAND MINUTE SALAMANDER
Thorius grandis – Hanken, Wake & Freeman 1999

IDENTIFICATION:
DISTRIBUTION:
Thorius grandis is endemic to the mountains northeast of Atoyac de Alvarez, Guerrero. Most localities are from the slopes of Cerro Teotepec, although one record exists for Cerro Toro Muerto (about 10 air km northwest of Cerro Teotepec). On the Atoyac/Milpillas highway most records exist between Puerto del Gallo (westernmost) and Jiguero (easternmost). Elevational distribution from 2495-3360 m.

HABITAT:
This species occurs in montane pine-fir and pine-oak-fir forests at high elevations, and within bamboo-tree fern cloud forest at it’s lowest locality. Most specimens are reported as being found beneath or within rotting logs and beneath the bark of dead trees, both standing or fallen.
NATURAL HISTORY:
This terrestrial salamander reproduces by direct developement, like all other species of Thorius.
TAXONOMY:
This species is closely related to T. omiltemi.
TYPE:
Described as Thorius grandis by Hanken, Wake and Freeman (1999). Holotype: MVZ 183384. Type locality: Puerto del Gallo, Guerrero, Mexico, elevation 2500 m. An adult female collected by Theodore J. Papenfuss, 22 December 1976.
PERSONAL NOTES:
I have no experience with this species.
CONSERVATION STATUS:
REFERENCES:
Hanken, J., Wake, D. B., and Freeman, H. L. 1999. Three New Species of Minute Salamanders (Thorius: Plethodontidae) from Guerrero, Mexico, Including the Report of a Novel Dental Polymorphism in Urodeles. Copeia 1999(4):917-931.

IDENTIFICATION: DISTRIBUTION: This species is known only from the type locality, in the Sierra Madre del Sur of central Guerrero, Mexico. Thorius infernalis certainly occurs over a broader region than is currently known, but much of this region of central Guerrero is inaccessable due to lack of roads.

HABITAT: The [...]]]> ATOYAC MINUTE SALAMANDER
Thorius infernalis – Hanken, Wake & Freeman 1999

IDENTIFICATION:
DISTRIBUTION:
This species is known only from the type locality, in the Sierra Madre del Sur of central Guerrero, Mexico. Thorius infernalis certainly occurs over a broader region than is currently known, but much of this region of central Guerrero is inaccessable due to lack of roads.

HABITAT:
The type locality was described by J. E. Cadle as: an area of steep slopes adjacent to a small stream. Hillsides are planted with coffee; riparian vegetation grows along the stream. The hillsides had recently been cleared of undergrowth, leaving much fresh-cut vegetation on the ground, in addition to a few logs and rocks to turn. The holotype and one paratype were collected beneath logs in the afternoon.
NATURAL HISTORY:
This species is thought to be terrestrial. Like other Thorius it reproduces by direct developement.
TAXONOMY:
TYPE:
Described as Thorius infernalis by Hanken, Wake and Freeman (1999). Holotype: MVZ 183426. Type locality: 13.7 km northeast (road from Atoyac to Puerto del Gallo) of El Paraiso, Guerrero, Mexico, elevation 1140 m. An adult male collected by J. E. Cadle, 18 November 1977.
PERSONAL NOTES:
I have no experience with this species.
CONSERVATION STATUS:
REFERENCES:
Hanken, J., Wake, D. B., and Freeman, H. L. 1999. Three New Species of Minute Salamanders (Thorius: Plethodontidae) from Guerrero, Mexico, Including the Report of a Novel Dental Polymorphism in Urodeles. Copeia 1999(4):917-931.

IDENTIFICATION: DISTRIBUTION: Thorius insperatus is known only from a single specimen, collected in the lower cloud forest near Vista Hermosa, Oaxaca, Mexico.

HABITAT: The only known specimen of this species was found beneath a log in lower cloud forest during the month of August. NATURAL HISTORY: Almost nothing is known of the [...]]]> VISTA HERMOSA MINUTE SALAMANDER
Thorius insperatus – Hanken & Wake 1994

IDENTIFICATION:
DISTRIBUTION:
Thorius insperatus is known only from a single specimen, collected in the lower cloud forest near Vista Hermosa, Oaxaca, Mexico.

HABITAT:
The only known specimen of this species was found beneath a log in lower cloud forest during the month of August.
NATURAL HISTORY:
Almost nothing is known of the habits of this extremely rare salamander.
T. insperatus presumably reproduces by direct developement, like all other species of Thorius. Presumably this species occurs in sympatry with Thorius smithi, but this has yet to be determined.
TAXONOMY:
TYPE:
Described as Thorius insperatus by Hanken and Wake (1994). Holotype: KU 66799. Type locality: Vista Hermosa, Oaxaca, Mexico. An adult male collected by J. B. Tulecke on 14 August 1961.
PERSONAL NOTES:
I have no experience with this species despite having spent some time at the type locality in Vista Hermosa, Oaxaca.
CONSERVATION STATUS:
REFERENCES:
Hanken, J., Wake, D. B. 1994. Five New Species of Minute Salamanders, Genus Thorius (Caudata: Plethodontidae), from Northern Oaxaca, Mexico. Copeia 1994(3):573-590.
Hanken, J., Wake, D. B., and Freeman, H. L. 1999. Three New Species of Minute Salamanders (Thorius: Plethodontidae) from Guerrero, Mexico, Including the Report of a Novel Dental Polymorphism in Urodeles. Copeia 1999(4):917-931.

IDENTIFICATION: DISTRIBUTION: HABITAT: NATURAL HISTORY: TAXONOMY: TYPE: PERSONAL NOTES: CONSERVATION STATUS: REFERENCES:

MACDOUGALL’S MINUTE SALAMANDER Thorius macdougalli – Taylor 1949

IDENTIFICATION: DISTRIBUTION: This species is known only from high elevations on Cerro Pelon, Llano de las Flores, and associated ridges in the Sierra de Juarez of Oaxaca, Mexico. HABITAT: Thorius macdougalli occurs in pine-oak-fir and pine-fir forests and their edges. It is most often discovered beneath logs, bark and within [...]]]>
Adult, 7,871′, Oaxaca, Mexico

MACDOUGALL’S MINUTE SALAMANDER
Thorius macdougalli – Taylor 1949

IDENTIFICATION:
DISTRIBUTION:
This species is known only from high elevations on Cerro Pelon, Llano de las Flores, and associated ridges in the Sierra de Juarez of Oaxaca, Mexico.
HABITAT:
Thorius macdougalli occurs in pine-oak-fir and pine-fir forests and their edges. It is most often discovered beneath logs, bark and within deep forest litter.

Pine Forest Habitat, 7,870′, Cerro Pelon, Oaxaca, Mexico

NATURAL HISTORY:
This species reproduces by direct developement like all other species of Thorius. T. macdougalli occurs in sympatry with T. boreas in and around Llano de las Flores, as well as on the top of Cerro Pelon. Additionally, T. aureus occurs with both these species in a ravine 1 km N of where Hwy. 175 crosses the summit of the Cerro.
TAXONOMY:
Highton (2000) suggested two additional cryptic species may exist within this complex.
TYPE:
Described as Thorius macdougalli by Taylor (1949). Holotype: AMNH 52136. Type locality: Cerro de Humo, Maquiltianguis, Oaxaca, Mexico. Collected by T. C. MacDougall on 2 March 1945.
PERSONAL NOTES:
In July, 2005 I happened upon two of these incredibly small salamanders in the high pine forest on Cerro Pelon, Oaxaca. They were both found beneath woody debris, and when uncovered they rapidly coiled and uncoiled in an attempt to escape. A total of 10 minutes was spent searching this locality, and no other reptiles or amphibians were found.
In July 2006 I again visited this locality during a period of favorable weather and despite my friend and I hunting about one hour we could not find any Thorius.
CONSERVATION STATUS:
REFERENCES:
Hanken, J., Wake, D. B. 1994. Five New Species of Minute Salamanders, Genus Thorius (Caudata: Plethodontidae), from Northern Oaxaca, Mexico. Copeia 1994(3):573-590.

IDENTIFICATION: DISTRIBUTION: HABITAT: NATURAL HISTORY: TAXONOMY: TYPE: PERSONAL NOTES: CONSERVATION STATUS: REFERENCES: