Cirripectes matatakaro, a new species of combtooth blenny from the Central Pacific, illuminates the origins of the Hawaiian fish fauna

Abstract

Included among the currently recognized 23 species of combtooth blennies of the genus Cirripectes (Blenniiformes: Blenniidae) of the Indo-Pacific are the Hawaiian endemic C. vanderbilti, and the widespread C. variolosus. During the course of a phylogeographic study of these species, a third species was detected, herein described as C. matatakaro. The new species is distinguished primarily by the configuration of the pore structures posterior to the lateral centers of the transverse row of nuchal cirri in addition to 12 meristic characters and nine morphometric characters documented across 72 specimens and ∼4.2% divergence in mtDNA cytochrome oxidase subunit I. The new species is currently known only from the Marquesas, Gambier, Pitcairns, Tuamotus, and Australs in the South Pacific, and the Northern Line Islands and possibly Johnston Atoll south of Hawaiʻi. Previous researchers speculated that the geographically widespread C. variolosus was included in an unresolved trichotomy with the Hawaiian endemic and other species based on a morphological phylogeny. Our molecular-phylogenetic analysis resolves many of the previously unresolved relationships within the genus and reveals C. matatakaro as the sister lineage to the Hawaiian C. vanderbilti. The restricted geographic distribution of Cirripectes matatakaro combines with its status as sister to C. vanderbilti to indicate a southern pathway of colonization into Hawaiʻi.

New insights into the diversity of cryptobenthic Cirripectes blennies in the Mascarene Archipelago sampled using Autonomous Reef Monitoring Structures (ARMS)

“…Cirripectes species previously reported from Reunion and Rodrigues are shown in Table 4, as based on visual surveys (Fricke et al, 2009; Letourneur et al, 2004), morphological (Fricke, 1999; Heemstra et al, 2004; Williams, 1988), and molecular studies (Collet et al, 2017; Hubert et al, 2015). Some of the original reference sequences for Cirripectes samples from Reunion were misidentified: it turned out that some C. stigmaticus were C. castaneus (BOLD:AAE2835) and all C. castaneus were C. randalli (BOLD:AAU0601; Hoban & Williams, 2020). Thus, C. stigmaticus (BOLD:AAE2834) was not genetically identified from Reunion prior to the present study (Table 4).…”

“…Further analyses revealed the existence of misidentified specimens in these databases. Some of these misidentifications have already been corrected and published but were not yet corrected in the BOLD database (BOLD:ADB2362 probably do not correspond to Cirripectes specimens in Chu et al, 2019; BOLD:AAU0601 is C. randalli in Hoban & Williams, 2020). The presence and problem of misidentified specimens in reference databases are well documented, even for Indo‐Pacific fishes (Leis, 2015; Pentinsaari et al, 2020).…”

“…The genus Cirripectes Swainson, 1839 (Family Blenniidae, Order Blenniiformes) comprises 24 recognized species of combtooth blennies, broadly distributed in the Indo‐Pacific from East Africa to Rapa Nui in the eastern Pacific (Hastings & Springer, 2009; Hoban & Williams, 2020; Williams, 1988). Currently, 14 species are recorded with COI DNA sequences in the BOLD database (Ratnasingham & Hebert, 2007), plus three genetically divergent groups that possibly represent not yet described new species.…”

Skimming for barcodes: rapid production of mitochondrial genome and nuclear ribosomal repeat reference markers through shallow shotgun sequencing

“…DNA barcoding has long been recognized as a critical component of biodiversity research ( Hebert et al, 2003 ; Ratnasingham & Hebert, 2013 ; DeSalle & Goldstein, 2019 ; Adamowicz et al, 2019 ), but available barcode reference databases remain incomplete ( Mugnai et al, 2021 ). More comprehensive regional reference datasets in global databases better support research goals and applications such as discovering new species ( Carpenter, Williams & Santos, 2017 ; Hoban & Williams, 2020 ), matching larval specimens to known adults ( Johnson et al, 2009 ; Hubert et al, 2010 ), and authenticating seafood labeling ( Marko, Nance & Guynn, 2011 ; Silva & Hellberg, 2021 ). Traditionally, DNA barcoding efforts relied on Sanger sequencing of single mitochondrial markers, particularly cytochrome oxidase subunit I (COI) for metazoans.…”

Unravelling the taxonomy of an interstitial fish radiation: Three new species of Gouania (Teleostei: Gobiesocidae) from the Mediterranean Sea and redescriptions of G. willdenowi and G. pigra

“…Above all, many cryptobenthic taxa contain morphologically similar or, at least at first glance, identical species, such that their overall biodiversity is drastically underestimated, even in considerably well‐studied groups or geographic regions ( e.g ., Conway et al ., 2014; Tornabene et al ., 2015; Wagner et al ., 2019; Winterbottom et al ., 2014). However, the inclusion of molecular methods in classic taxonomic studies has proven to be particularly effective for overcoming these obstacles and in recent years genetic data have become a key tool for resolving phylogenetic relationships among and within cryptobenthic taxa ( e.g ., Almada et al ., 2008; Conway et al ., 2014; Henriques et al ., 2002; Hoban & Williams, 2020; Kovačić et al ., 2020; Tornabene et al ., 2010; Victor, 2013; Winterbottom et al ., 2014).…”