title: Behaviour, feeding habits and ecology of the blind catfish Phreatobius sanguijuela (Ostariophysi: Siluriformes).
abstract: The subterranean fish Phreatobius sanguijuela, originally described from Bolivia, was captured in different wells near São Francisco do Guaporé, Rondônia State, Brazil. Thirty wells were investigated in April and July 2012, and September 2013. These surveys resulted in the capture of 58 individuals from eight wells and comprised three to 14 individuals per well. The capture of the individuals allowed a detailed evaluation of their colours in life, behaviour in the field and in captivity, aspects of their biology, confirmation of the species identification and provided new diagnostic characteristics to distinguish between P. sanguijuela and Phreatobius dracunculus. Cannibalism, territorialism, agonistic interactions and phototaxis behaviour were not observed. Phreatobius sanguijuela exhibited cryptobiotic habits and two behaviours under stressful conditions. The analysis of stomach contents reveals that this species apparently feeds on invertebrates, almost exclusively on earthworms. The sex ratio was 1:1. The absence of opercular movement during the resting period associated with intense blood irrigation of the skin indicates a possible cutaneous respiration as an alternative form of gas exchange. Local people often mistake P. sanguijuela for helminths and have the habit of releasing non-native fishes into the wells or to use chemicals to eliminate them. The consequence of this habit for the conservation of the species requires further evaluation.
authors.affiliation: Museu de Zoologia da Universidade de São Paulo, Av. Nazaré, 481, Caixa Postal 42494, CEP 04299-970, São Paulo, SP, Brazil.
authors.forename: W M
authors.initials: WM
authors.lastname: Ohara
authors.affiliation: Universidade Federal de Rondônia, Departamento de Engenharia de Pesca, Rua da Paz, 4376, CEP 76916-000, Presidente Médici, RO, Brazil.
authors.forename: I D
authors.initials: ID
authors.lastname: Da Costa
authors.affiliation: Coleções Zoológicas e Laboratórios Integrados, Universidade Federal de Rondônia, BR 364, Km 9.5, CEP 76808-659, Porto Velho, RO, Brazil.
authors.forename: M L
authors.initials: ML
authors.lastname: Fonseca
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D001938:Brazil; D002397:Catfishes; D005260:Female; D005399:Fishes; D005766:Gastrointestinal Contents; D008297:Male; D010858:Pigmentation; D012744:Sex Ratio; D060986:Water Wells
keywords: Brazil; Neotropical; Rondônia; cutaneous respiration; new record; subterranean fish