Phylogeny and classification Historically, subfamily Hydrophiinae included all "
sea snakes" and was commonly used to refer to both the true sea snakes (tribe
Hydrophiini) and the sea kraits (
Laticauda). However, large-scale molecular phylogenetic analyses and studies integrating phenotypic data (including morphological, ecological, and cytogenetic characteristics) with molecular data support the hypothesis that
Laticauda is the sister group to all other hydrophiines. This clade containing all hydrophiines except
Laticauda is sometimes referred to as
Oxyuraninae. Given its basal position,
Laticauda is sometimes placed in a separate subfamily,
Laticaudinae, sister to Hydrophiinae
sensu stricto. Molecular evidence further suggests that true sea snakes (Hydrophiini) are more closely related to terrestrial
oxyuranine elapids than to
Laticauda, implying that marine adaptations evolved convergently in the two groups. Sanders et al. (2008) identified the closest extant relatives of Hydrophiini as Australasian terrestrial elapids. (Sea snakes are marked with asterisks.) == References ==