Phylogenetic tree of concatenated ND2 and COI sequences. Bayesian phylogenetic tree of concatenated mitochondrial ND2 and COI sequences for Squalus species used in this study, which was concordant with maximum likelihood methods. Numbers at nodes represent maximum likelihood bootstrap support/Bayesian posterior probability.

Haplotype networks for 20 individuals from four putative Squalus species. TCS plots show two the mitochondrial genes (COI and ND2) sequenced this study. The size of the circles or wedges represents the number of samples within each haplotype, and uninterrupted branches represent single mutational steps.

Holotype. Lateral view of Squalus hawaiiensis sp. n. holotype (UF241161, female 750.5 mm TL).

Holotype. Ventral view of Squalus hawaiiensis sp. n. holotype (UF241161, female 750.5 mm TL).

SEM images of dermal denticles. Three views of dermal denticles from adult male (TL = 72.5 cm) Squalus hawaiiensis.

Holotype. A First dorsal fin B second dorsal fin C pectoral fin of Squalus hawaiiensis holotype (UF241161, female 750.5 mm TL).

Caudal fin of Squalus hawaiiensis sp. n. A Holotype (UF241161, female 750.5 mm TL) B fresh adult male C fresh adult female.

Images of the Hawaiian spurdog, Squalus hawaiiensis. A Lateral view of adult female Squalus hawaiiensis, drawing by R. McPhie B embryonic Squalus hawaiiensis, lateral and dorsal views, drawings by R. McPhie C embryonic Squalus hawaiiensis, dorsal view. Photo by RDG.