Maculabatis arabica Manjaji-Matsumoto & Last, 2016

Fernando, Daniel, Bown, Rosalind M. K., Tanna, Akshay, Gobiraj, Ramajeyam, Ralicki, Hannah, Jockusch, Elizabeth L., Ebert, David A., Jensen, Kirsten & Caira, Janine N., 2019, New insights into the identities of the elasmobranch fauna of Sri Lanka, Zootaxa 4585 (2), pp. 201-238 : 211-212

Maculabatis arabica Manjaji-Matsumoto & Last

( Figs. 2D , 8 C–E)

An immature specimen (SL-6) from the Pukulam landing site in the North Western Province was difficult to identify to species based on morphology alone. The rhombic disc and sparse white spots on the lateral margins of the tail immediately anterior to, adjacent to, and immediately posterior to the spine suggested it was a member of the genus Maculabatis Last, Naylor & Manjaji-Matsumoto. In the tree resulting from the Neighbor-Joining analysis, this specimen clustered with our reference specimen of Maculabatis arabica (MM-602; MK335258 ) from the Gulf of Oman. It differed from this specimen by only 1 bp, and is likely an immature individual of the species. Of note is that our specimen was somewhat inconsistent with the description of immatures of M. arabica presented by Manjaji-Matsumoto & Last (2016). Whereas they described the tail of immatures of M. arabica less than 33 cm in disc width (DW) to bear conspicuous white bands on the upper half of the tail behind the caudal sting, the tail of the specimen from Sri Lanka (DW of 17.6 cm) had inconspicuous white spots that were restricted to the region of the tail anterior and posterior to the tail spine. Examination of additional immature and adult specimens from Sri Lanka is required to confirm this identification.

To our knowledge, this is the first report of this species from Sri Lanka.

Figures

FIGURE 2. Neighbor-Joining trees of p-distances based on 1,044 bp of aligned NADH2 sequence data for individual batoid genera or groups of genera. Taxon names are followed by country, host specimen number (in parentheses), and GenBank number. Outgroup taxa used in each analysis were omitted from the individual trees. Scale bar values indicate substitutions per site. Specimens deposited in the Blue Resources Trust Ichthyology Collection are indicted by stars (see text for details). A. Aetobatus (Aetobatidae). B. Brevitrygon (Dasyatidae). C. Himantura (Dasyatidae). D. Maculabatis (Dasyatidae). E. Neotrygon (Dasyatidae). F. Pastinachus (Dasyatidae). G. Pateobatis (Dasyatidae). H. Urogymnus (Dasyatidae).

FIGURE 8. Maculabatis gerrardi (A–B) and Maculabatis arabica (C–E) (Dasyatidae). A. Dorsal surface of mature female (SL-40); inset showing scapular denticles. B. Dorsal surface of immature male (SL-58); inset showing scapular denticles. C. Dorsal surface of immature female (SL-6); inset showing scapular denticles. D. Oronasal region of immature female (SL-6). E. Tail base and anterior tail region of immature female (lateral view; SL-6).