Scomber indicus, a new species of mackerel (Scombridae: Scombrini) from Eastern Arabian Sea

Abstract

Scomber indicus, a new species of mackerel is described based on the specimens collected from the eastern Arabian Sea. The species is differentiated from its nearest congener Scomber australasicus, in having 29-32 gill rakers on lower limb of first gill arch, posteriormost part of hypohyal blunt, with presence of a pit between the hypohyal and the ceratohyal and also in having a posteriorly directed haemal spine which is deeply curved in the basal region. Genetic differentiation and divergence between the newly described species and the 4 valid species of the genus Scomber viz., S. scombrus, S. japonicus, S. australasicus and S. colias were compared using cytochrome c oxidase 1 and cytochrome b gene sequences. The new species was found closest to S. colias followed by S. japonicus with Kimura 2 parameter (K2P) values of 1.4 and 1.8% respectively. In the phylogenetic tree, sequences of Scomber indicus sp. nov. formed a distinct well separated clade with significant bootstrap values as compared to the sequences of S. scombrus, S. japonicus, S. australasicus and S. colias indicating their distinctiveness and separate species status.

Molecular analyses of carangid fish diets reveal inter‐predation, dietary overlap, and the importance of early life stages in trophic ecology

“…C. crysos , C. latus , and H. amblyrhynchus all have approximately terminal opening mouths (Abdussamad et al., 2013). Prey items identified for C. crysos are consistent with existing knowledge about the species' diet that describes it as an opportunistic predator consuming mainly pelagic organisms, but with benthic prey representing part of its diet (Sley et al., 2009).…”

“…Although there is generally considerable overlap in the diet of many of the sampled taxa, Costello plots (Figure 2) and nMDS ordination analyses (Figure 3) indicate that, even with limited sampling numbers, a trend can be seen where foraging behavior is inferred to be associated with distinct use of habitats and the water column by these carangid species. The orientation of the mouth is generally associated with different and specific foraging patterns or environmental exploration (Abdussamad et al., 2013). The susceptibility of different prey species to superior, lateral, or inferior predatory attacks may reduce the trophic niche overlap between these species despite sharing opportunistic generalist feeding patterns (Selleslagh & Amara, 2015).…”

Untangling the taxonomic ambiguities of the spotted seerfish Scomberomorus guttatus with the description of a new species from India

“…The use of otoliths as indicators for stock identity has been previously advocated and is a robust and cost‐effective method for stock discrimination (Campana & Casselman, 1993; Cardinale et al, 2004). Several researchers reported otoliths to have species‐specific morphology and considered it a reliable taxonomic tool (Abdussamad et al, 2015, 2016, 2022; Joshi et al, 2012; Karahan et al, 2014; Libungan et al, 2015; Libungan & Pálsson, 2015). Similar studies have been conducted in many Scomberomorus species globally to discriminate morphotypes (Johnson, 1996; Ramirez‐Perez et al, 2010; Zhang et al, 2013, 2016; Zischke et al, 2016).…”

“…We used morphology, morphometrics, meristics, shape analysis of otoliths, and molecular tools in the study. The otoliths of finfish possess species‐specific morphology, and researchers consider it a reliable alternative taxonomic tool (Abdussamad et al, 2015, 2016, 2022; Joshi et al, 2012; Karahan et al, 2014; Libungan et al, 2015; Libungan & Pálsson, 2015). DNA barcoding can also be a reliable confirmative tool for species with high resolution in apparently similar organisms (Tautz et al, 2003).…”

Reproductive Biology and Feeding Habits of Razorbelly Scad, Alepes kleinii (Bloch, 1793), in the Northeastern Arabian Sea

“…The family Carangidae is one of the largest families of marine teleost, comprising approximately 32 genera and 140 species worldwide (Nelson, Grande, and Wilson, 2016). Of these, approximately 60 species from 20 genera have been reported from the northern Indian Ocean (Abdussamad et al ., 2013). Among the scads, the genus Alepes is one of the least studied genera in the family and has a complex taxonomic history.…”