Larval Development in Tropical Gar (Atractosteus tropicus) Is Dependent on the Embryonic Thermal Regime: Ecological Implications under a Climate Change Context

In ectotherm species, environmental temperature plays a key role in development, growth, and survival. Thus, determining how affects fish populations is of utmost importance to accurately predict the risk climate change over fisheries aquaculture, critical warrant nutrition food security coming years. Here, potential effects abnormal thermal regimes (24, 28 32 °C; TR24, TR28, TR32, respectively) exclusively applied during embryogenesis tropical gar (Atractosteus tropicus) has been explored decipher consequences on hatching growth from fertilization 16 days post-fertilization (dpf), while skeletal development body morphology were at dpf. Egg incubation higher temperatures induced an early mouth opening. A rate was obtained eggs incubated °C when compared those 24 °C. No differences found survival dpf, with values ranging 84.89 88.86%, but increased wet weight standard length larvae TR24 TR32 groups. Thermal regime also altered which occurs. Larvae group showed advanced cartilaginous structures reduced dpf TR28 Furthermore, this seemed determine morphology. Based biometric measures, principal component analysis along each clustered together, population remaining clearly separated other. The current study shows changes may induce craniofacial morphological alterations stages contribute understanding possible global warming its ecological implications.