Molecular analyses reveal a lack of genetic structuring in the scalloped hammerhead shark, Sphyrna lewini (Griffith & Smith, 1834) along the Indian coast

• Published in: Marine biodiversity Vol. 50; no. 2; p. 18
• Main Authors: Sukumaran, Sandhya, Sebastian, Wilson, Mukundan, Lakshmi P., Menon, Muktha, Akhilesh, K. V., Zacharia, P. U., Gopalakrishnan, A.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-04-2020; Springer Nature B.V
• Subjects: Animal Systematics/Taxonomy/Biogeography; Biodiversity; Biomedical and Life Sciences; Bycatch; Carnivorous animals; Coasts; Cytochrome-c oxidase; Cytochromes; Demography; Differentiation; Evolution; Fisheries; Fishing; Freshwater & Marine Ecology; Genetic diversity; Genetic structure; Genetic variation; Haplotypes; Investigations; Life Sciences; Marine fishes; Marine molluscs; Mitochondrial DNA; Nucleotide sequence; Ocean basins; Oceans; Philopatry; Plant Systematics/Taxonomy/Biogeography; Population; Population genetics; Sharks; Short Communication; Sphyrna lewini; Threatened species; Arabian Sea; Mumbai India; Indian Ocean; Bay of Bengal; India; Effective population size; Genetic population structure; Endangered; IUCN Red list
• ISSN: 1867-1616; 1867-1624
• DOI: 10.1007/s12526-020-01040-4

The scalloped hammerhead shark,
Sphyrna lewini
(Griffith and Smith, 1834), is an important species along the Indian coast both in the Arabian Sea and Bay of Bengal. As per the IUCN Red List Assessment, the scalloped hammerhead shark is categorized as “globally endangered.” We investigated the intra-specific genetic diversity and population genetic structure of
S. lewini
along the Indian coast (Arabian Sea and Bay of Bengal) by analyzing mitochondrial cytochrome C oxidase 1 and control region sequences, respectively. Furthermore, comparisons of the sequence data generated from the present study with the sequences of
S. lewini
retrieved from GenBank revealed the presence of three (3) haplogroups corresponding to Indian/Indo-Pacific, Atlantic, and Pacific regions. A lack of genetic differentiation within the Indian coast and significant differentiation between ocean basins (
F
ST
; 0.80;
p
 < 0.001) indicated female philopatry as mitochondrial DNA is maternally inherited. Hammerhead sharks are inherently vulnerable to fishing practices directly and indirectly (as bycatch) due to their evolutionary distinct features like cephalofoil. Specialized species-specific management measures are urgently needed to protect these precious resources of the oceans.