Typhliasina pearsei (Hubbs, 1938)
Mexican blind brotula
photo by Contreras-Balderas, S.

Family:  Dinematichthyidae (Viviparous brotula)
Max. size:  9.7 cm SL (male/unsexed); 8.9 cm SL (female)
Environment:  demersal; freshwater; depth range 0 - 70 m
Distribution:  Central America: Yucatan Peninsula, Mexico.
Diagnosis:  Dorsal soft rays (total): 75-87; Anal soft rays: 59-68; Vertebrae: 40-43. This species is distinguished by the following characters: anterior nostril placed low on snout; tip of opercular spine free; 2 pairs of psedoclaspers, inner one positioned in front of outer one; eyes not visible (eyes minute black dots in specimens less than 20 mm SL); head naked; otolith with fused colliculi; 3 lower preopercular pores; maxillary strongly vertically expanded posteriorly, knob at rear corner; 5-7 prolonged rakers on anterior gill arch; anterior anal fin pterygiophore elongated; pseudobranchial filaments absent (Ref. 55786).
Biology:  Uncommon species found in caves and sinkholes (Ref. 34024). Associated with the blind synbranchid fish Ophisternon infernale (Hubbs, 1938) and several blind crustacean species. In only one cave, it was found with the catfish Rhamdia guatemalensis (Günther, 1864). This species does not react to flashlights, but darted away at the slightest vibration; it seems to feed on troglobitic shrimps and mysids. Newly-born juveniles are light yellow and about 20 mm long (Ref. 55786).
IUCN Red List Status: Near Threatened (NT); Date assessed: 05 October 2018 Ref. (130435)
Threat to humans:  harmless


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