A regional Taxonomic Analysis of Commercial Fishes in Cabo Verde based on Genetic Data: A Case Study on the Haemulidae Family

Abstract

Haemulidae is one of the fish families that has given confusion regarding to its taxonomy and geographical distribution. In Cabo Verde, the species are widely caught for consumption, and it is therefore imperative to clarify the species that have a distribution in the archipelago, as well as to make the phylogenetic relationship between the species that are part of the same family. So, the main objective of this study was to evaluate the relationship between species of Haemulidae based on morphological data and genetic diversity, using a standard mtDNA genetic marker. To do this, specimens were collected for morphological analysis, and 35 tissue samples from Cabo Verde were sequenced. In total, 75 DNA sequences come from both published and unpublished sources. The morphological data and the tissues collected showed the existence of four (4) species in Cape Verde: Pomadasys incisus, Parapristipoma humile, Pomadasys jubelini, and Parapristipoma macrops, which were confirmed by DNA barcoding. The maximum likelihood value among Haemulidae species was moderate, and intraspecific distances ranged from 0.005 to 0.301, helping to confirm the 4 species. The species P. incisus demonstrated absolute monophyly, confirming its distinct status. While P. jubelini was monophyletic, it was grouped with Pomadasys perotaei and Pomadasys rogerii. On the other hand, Brachydeuterus auritus proved to be a monophyletic species. There was a complete separation of P. humile, but in this same clade, a species of P. rogerii appeared, indicating a potential taxonomic error. The P. macrops specimens display a separation within the P. humile branch, revealing close genetic proximity. In P. rogerii population structure, minimal genetic variation was noted and P. macrops and P. humile displayed low genetic distance, evident in a sparse mutational-step haplotype network. Conversely, P. incisus samples exhibited notable Cabo Verde genetic variance compared to Mediterranean and South Atlantic counterparts. This revealed two distinct groups: an exclusive Cabo Verde group and another including haplotypes from different regions. This study highlights the fusion of morphology and genetics to better identify the species of the Haemulidae family. Genetic validation of Cape Verdean species helps resource management. The research contributes new knowledge, forming a basis for future molecular and taxonomic studies, and serving as reference data for DNA barcodes.