RHINOBATIDAE (GUITARFISHES)

Henderson, Aaron C., Reeve, Alan J., Jabado, Rima W. & Naylor, Gavin J. P., 2016, Taxonomic assessment of sharks, rays and guitarfishes (Chondrichthyes: Elasmobranchii) from south-eastern Arabia, using the NADH dehydrogenase subunit 2 (NADH 2) gene, Zoological Journal of the Linnean Society 176 (2), pp. 399-442 : 431

RHINOBATIDAE (GUITARFISHES)

Five putative rhinobatid species from three genera were assessed, including two reportedly undescribed species ( Henderson et al., 2007). Each putative species formed a distinct cluster ( Fig. 2 ), with a between-group mean distance of 9.28 ± 0.54%. One of the undescribed species, which was designated Rhinobatos sp. , is superficially similar to Rhinobatos punctifer , although the latter possesses a notably wider head and generally bears solid spots, whereas the former generally bears ocellated spots and occasionally additional patterning ( Fig. 8 ). Despite their morphological similarity, there was a large mean distance between these two species ( Table 4). There was strong branch support for the separation of two of the Rhinobatos sp. specimens from the rest of the cluster, and the mean distance between these two specimens and the remaining Rhinobatos sp. specimens was 2.12 ± 0.42% The second genus was Acroteriobatus , and

Figures

Figure 2. Neighbour-joining tree for an 829-bp fragment of the NADH2 gene from 1487 elasmobranch specimens from south-eastern Arabia. Values in parentheses indicate sample size (n) and within-group mean genetic distance (D). Bootstrap values are based on 1000 replications and only values ≥ 95% are shown.

Figure 8. Rhinobatos sp. (top) is morphologically and genetically distinct from Rhinobatos punctifer (middle). The bottom image shows Acroteriobatus sp.