RHYNCHOBATIDAE (WEDGEFISHES)

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

RHYNCHOBATIDAE (WEDGEFISHES)

One species was assessed, namely Rhynchobatus djiddensis , and it formed two distinct sub-clusters ( Fig. 2 ). Their between-group mean distance was 3.87 ± 0.81%. Although this species was not assessed by Naylor et al. (2012), congeners from that study separated the R. djiddensis sub-clusters when all were viewed together ( Fig. 10 ). Considerable variation in pattering and rostrum shape was also noted among these specimens ( Fig. 11 ); therefore, the two sub-clusters have been designated R. cf. djiddensis 1 and R. cf. djiddensis 2.

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 10. Neighbour-joining tree for an 829-bp fragment of the NADH2 gene for Rhynchobatus spp. from southeastern Arabia and from Naylor et al. (2012). Bootstrap values are based on 1000 replications and only values ≥ 95% are shown.

Figure 11. Species commonly identified as Rhynchobatus djiddensis from south-eastern Arabia display morphological and colour variations. The specimen in the top image possesses an obviously narrower and longer rostrum. The results of the present study suggest there are at least two local lineages within this genus.