Evaluation of somatic indexes in the endangered and endemic killifish Tlaloc hildebrandi (Cyprinodontiformes: profundulidae)

ABSTRACT Tlaloc hildebrandi is a small (<130 mm) freshwater fish endemic to Southwest Mexico and is listed as endangered through habitat loss and invasive species. We determine and compare the parameters of the length–weight relationship, relative weight, and condition factor among different populations of the endemic killifish, T. hildebrandi. Fulton’s condition factor (K), relative weight (Wr), and the length–weight relationship were estimated for three killifish populations throughout its distribution range in the highlands of Chiapas, México. The Wr was significantly lowest in fishes where there are higher anthropogenic activities. The somatic indexes and the length–weight relationships for T. hildebrandi are hereby published for the first time in both the scientific literature and databases, such as Fishbase.