First genetic record of the non‐native muzzled blenny Omobranchus punctatus (Teleostei: Blenniidae) in the Atlantic Coast of Central and South America

Abstract

In this study we sequenced two mitochondrial (COI and 16S rRNA) and one nuclear (18S rRNA) gene fragment of an introduced muzzled blenny (Omobranchus punctatus) specimen collected from the Orinoco Delta (Gulf of Paria estuary) in Venezuela. This is the first genetic data generated for this species' introduced range in Central and South America, suggesting an introduction from the Indian Ocean.

Clarifying the taxonomy of some cryptic blennies (Blenniidae) in their native and introduced range

“…Our phylogenetic analyses are in agreement with those of Gibbs et al 31 , Cabezas et al 30 and Mehraban et al 32 , recovering three well differentiated and supported mitochondrial lineages within O. punctatus group (Clades A, B and C) (Figs. 2 and 3), which were also confirmed by three different approaches of species delimitations methods (Fig.…”

“…Although Omobranchus Valenciennes 12 is the most species-rich genus in the Omobranchini tribe of the Blenniidae, with 23 valid species 24,41 , its actual diversity remains underestimated 7,[30][31][32] .…”

“…The use of integrative taxonomic approaches (combining morphological, genetic, and ecological data, among other characters) has shown to be the best strategy to produce well-supported species delimitations 45,46 . However, most studies concentrate exclusively on documenting current species diversity or identifying independent lineages without naming them 46 , as is also the case for previous studies on O. punctatus [30][31][32] . The proper naming of the detected lineages is essential in biodiversity assessments and for its subsequent conservation planning 45 , especially when dealing with IAS 47 .…”

“…Although there is no genetic data for this exotic blenny in the Bay of Bengal (the putative origin of invasive populations), and only one mitochondrial sequence is available from its introduced range (Venezuela) 30 (Supplementary Table S3), recent molecular analyses showed the existence of several highly divergent genetic lineages across the species' distribution. First, the study of Gibbs et al 31 showed the existence of three deeply divergent lineages within O. punctatus: two lineages in the Eastern Indian Ocean (EIO), separated by the Sunda Shelf Barrier (SSB), were confirmed by both mitochondrial and nuclear data; a third lineage was identified in Japan with nuclear markers, with no mtDNA data currently available for the species in this region.…”

“…Later, Mehraban et al 32 , found an additional highly divergent mtDNA lineage in the Oman Sea, which the authors suggested could correspond to the originally described O. punctatus, due to the proximity to the species type locality (Mumbai = Bombay, India). Recently, a phylogenetic study showed that populations outside O. punctatus' native range, specifically those from the Gulf of Paria in Venezuela, clustered within the clade of individuals from the west of the SSB 30 . These data, together with the fact that the species is continuingly spreading in the Atlantic coast, highlight the urgent need to resolve O. punctatus' taxonomy.…”