Cortez Barnacle Blenny

description

To 6 cm (2.4 in) TL (Robertson and Allen 2015). Probably Punta Marquis (23 ° 56 ’ N, 11 ° 52 ’ W), southern Baja California and Gulf of California (Lin and Galland 2010). 0 – 13 m (43 ft) (Lin and Galland 2010). Previously as A. macrospilus — now known to be a species limited to mainland Mexico as far north as Mazatlán (Grantly Galland, pers. comm. to M. L.).

Checklist of marine and estuarine fishes from the Alaska-Yukon Border, Beaufort Sea, to Cabo San Lucas, Mexico

description

Description. Variable meristic data summarized in Table 4. All examined paratypes with 11 precaudal vertebrae; holotype with 12. No variation in pectoral-fin rays (13), primary caudal-fin rays (13), anal-fin spines (2), pelvic-fin spines (1), and pelvic-fin rays (3). Body long and slender (body depth in standard length nearly 6.5 times, Table 5). Head long (contributing to nearly 20 % of standard length, Table 5). One pair of usually unbranched supraorbital cirri; occasionally shallowly branched and rarely deeply branched, never more than once. Nasal cirri on anterior nostrils and always branched, occasionally more than once. No cirri on posterior nostrils. Dorsal fin single, notched – at 24 th spine on holotype. Caudal fin truncate. Upper jaw large (about 1.8 times in head, Table 5) and always extending beyond level of posterior edge of orbit and nearly as far back as dorsal-fin origin. Several bones of neurocranium covered with spines (Fig. 4). Frontals with most well developed spine field, forming diamondshaped patch, extending posteriorly from point in interorbital space (Fig. 4). The following measurements (mm) were taken from the holotype: standard length 43.6; head length 10

Molecular analysis of Acanthemblemaria macrospilus (Teleostei: Chaenopsidae) with description of a new species from the Gulf of California, Mexico

diagnosis

Diagnosis. Acanthemblemaria hastingsi can be distinguished from other Pacific members of this genus excluding its closest relatives, A. macrospilus and A. mangognatha, by combination of a single row of large brown blotches along its lateral midline and pointed (vs. club-like or ridge-like) head spines (Figs. 3 and 4). It can be distinguished from A. macrospilus and A. mangognatha by a dark swath of melanophores on the dorsal fin in both males and females that highlights the bright orange coloration on that fin (Fig. 3 B); presence of scattered melanophores reaching the tip of the lower jaw; and expression of orange as the primary bright head color. Acanthemblemaria hastingsi is further distinguishable from A. macrospilus by 71 fixed mutations in COI and 20 fixed mutations in the D-loop region of its mitochondrial genome (Tables 2 and 3).

Molecular analysis of Acanthemblemaria macrospilus (Teleostei: Chaenopsidae) with description of a new species from the Gulf of California, Mexico

discussion

Remarks. We provide molecular and morphological evidence that the formerly recognized color morphs of A. macrospilus are distinct species. This observation of closely related species living on either side of, and separated by, the Sinaloan Gap is not unique and occurs in at least three other pairs of chaenopsid tube blennies (Hastings 2000). The identification of two mitochondrial lineages with unique haplotypes (Fig. 2) and abundant fixed mutations (Tables 2 and 3) adheres to the definition of unique evolutionary histories in the Phylogenetic Species Concept (Mishler & Theriot 2000). In addition, the COI divergence value of 15.50 % is much higher than that in previously studied congeneric Australian fish species pairs (of 9.9 %; Ward et al. 2005) further suggesting the existence of two species. In addition to mitochondrial evidence, we also attempted to find independent genetic support from nuclear DNA. Based on nuclear intron marker S 7 - 1 data, differentiation between the two mitochondrially diagnosable species is supported by the significant fixation index, but no genealogical pattern was observed. Even though nuclear intron markers are thought to be highly variable and common

Molecular analysis of Acanthemblemaria macrospilus (Teleostei: Chaenopsidae) with description of a new species from the Gulf of California, Mexico