Fig. 1. Morphological phylogeny of the Family Scombridae showing its two subfamilies, Gasterochismatinae and Scombrinae, the latter composed of four Tribes. The bonitos (Tribe Sardini) and tunas (Thunnini) are sister groups. Letter abbreviations for the five tuna genera: Al, Allothunnus; A, Auxis; E, Euthynnus; K, Katsuwonus; T, Thunnus. Modified from Collette et al. (2001); Graham and Dickson (2000).