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Hongjamrassilp, W, Summers AP, Hastings PA.  2018.  Heterochrony in fringeheads (Neoclinus) and amplification of an extraordinary aggressive display in the Sarcastic Fringehead (Teleostei: Blenniiformes). Journal of Morphology. 279:626-635.   10.1002/jmor.20798   AbstractWebsite

The Sarcastic Fringehead (Neoclinus blanchardi, Teleostei) exhibits an extreme version of a common aggressive display, the gaping display, in which an open mouth is presented toward an opponent. Males of this species have extremely long jaws that extend posteriorly well past the posterior margin of the head and are flared laterally during the gaping display. In this study, we explored morphological traits related to this extraordinary display in this and related species of blennies. Morphological modifications include enlargement of the buccopalatal membrane, elongation of the maxilla via an uncalcified posterior extension, and evolution of a novel hinge between the anterior maxilla and lacrimal bones permitting lateral movement of the upper jaw. Geometric morphometry using the truss network system, thin-plate spline, and PCA of three closely related species of Neoclinus indicate that the elongate maxilla of N. blanchardi most likely evolved via acceleration (faster growth compared to outgroups) and hypermorphosis (continued growth to a larger body size), both forms of peramorphic heterochrony. Coloration and fluorescence of the buccopalatal membrane may also serve to amplify the extraordinary gaping display of the Sarcastic Fringehead.

Galland, GR, Erisman B, Aburto-Oropeza O, Hastings PA.  2017.  Contribution of cryptobenthic fishes to estimating community dynamics of subtropical reefs. Marine Ecology Progress Series. 584:175-184.   10.3354/meps12364   Abstract

Small, cryptic (cryptobenthic) fishes are an under-surveyed component of reef fish assemblages that can account for a significant amount of diversity, function, and structure of reef fish communities. A complete picture of reef fish dynamics requires an accounting of these species and inclusion of them in analyses of community ecology. We report the results of a large-scale, quantitative study of the rocky reef fish community in the Gulf of California (GOC), where we collected cryptobenthic fishes and surveyed conspicuous fishes to calculate species richness, density, biomass, and community metabolism of the entire fish assemblage. We catalogued 20 764 individuals, representing 112 species in 36 families. Cryptobenthic fishes accounted for more than 40% on average of the species richness per site but were generally unobserved during visual surveys. They also accounted for more than 95% of the total fish abundance and up to 56% of the fish community metabolic requirement, both a likely result of their small body size. The relative contribution of cryptobenthic fishes to the entire quantitatively sampled assemblage differed between the northern and southern GOC, with the north being relatively ‘more cryptobenthic’ than the south. This study is the first to combine quantitative surveys and collections of the entire fish assemblage in the GOC and is one of the most extensive of its kind for any ocean basin, to date. Our results demonstrate the importance of quantifying all size classes and all functional groups when studying the ecology of diverse vertebrate communities.

Sibert, EC, Cramer KL, Hastings PA, Norris RD.  2017.  Methods for isolation and quantification of microfossil fish teeth and elasmobranch dermal denticles (ichthyoliths) from marine sediments. Palaeontologia Electronica. 20:1-14. Abstract

Ichthyoliths — microfossil fish teeth and shark dermal scales (denticles) — are found in nearly all marine sediments. Their small size and relative rarity compared to other microfossil groups means that they have been largely ignored by the paleontology and paleoceanography communities, except as carriers of certain isotopic systems. Yet, when properly concentrated, ichthyoliths are sufficiently abundant to reveal patterns of fish abundance and diversity at unprecedented temporal and spatial resolution, in contrast to the typical millions of years-long gaps in the vertebrate body fossil record. In addition, ichthyoliths are highly resistant to dissolution, making it possible to reconstruct whole fish communities over highly precise and virtually continuous timescales. Here we present methods to isolate and utilize ichthyoliths preserved in the sedimentary record to track fish community structure and ecosystem productivity through geological and historical time periods. These include techniques for isolation and concentration of these microfossils from a wide range of sediments, including deep-sea and coral reef carbonates, clays, shales, and silicate-rich sediments. We also present a novel protocol for ichthyolith staining using Alizarin Red S to easily visualize and distinguish small teeth from debris in the sample. Finally, we discuss several metrics for quantification of ichthyolith community structure and abundance, and their applications to reconstruction of ancient marine food webs and environments.

Brusca, RC, Alvarez-Borrego S, Hastings PA, Findley LT.  2017.  Colorado River flow and biological productivity in the Northern Gulf of California, Mexico. Earth-Science Reviews. 164:1-30.   10.1016/j.earscirev.2016.10.012   AbstractWebsite

A review of published research indicates that the Northern Gulf of California is, historically and currently, one of the most biologically productive marine regions on Earth. This high productivity is driven by a unique mix of factors, including: coastal upwelling, wind-driven mixing, extreme tidal mixing and turbulence, thermohaline circulation that moves intermediate waters into the mixed layer, coastal-trapped waves, regular sediment resuspension, and, to a lesser extent, agricultural runoff, released nutrients from erosion of ancient Colorado River Delta sediments, and perhaps input from decomposing tidal-flat plant debris. It has been suggested that decreased Colorado River flow, due to anthropogenic water impoundments and diversions, has had a negative impact on the health of the Northern Gulf of California ecosystem, particularly by reducing primary productivity and/or stock production of finfish and shellfish. However, there is no evidence that surface flow from the Colorado River is now, nor has ever been an important driver of primary productivity in the Northern Gulf, and nutrient/chlorophyll studies show no relationship to Colorado River flow (or, if anything, reduced nutrient/chlorophyll levels occur during high river-flow periods). And, there is very limited and equivocal evidence to support the claim that reduced river flow has significantly impacted secondary productivity in the Northern Gulf. The marine ecosystem of the Northern Gulf remains rich in nutrients, high in biodiversity and productivity, and appears to continue to be healthy, except for the impacts of historical and current fisheries. Human extraction of shrimp, Gulf corvina, totoaba (largely illegally), and other marine resources, remain very high in this region. There also is no evidence that reduced Colorado River flow has negatively impacted the health of the critically endangered vaquita porpoise, and assertions that it has done so deflect attention from the actual cause of decline-bycatch in legal and illegal gillnet fisheries. A review of Colorado River Delta research confirms that, historically and perhaps as long as the river has reached the Gulf of California, there have been long periods of no flow, or greatly reduced flow to the sea. Thus, the ecosystem is historically adapted to broadly fluctuating river flows and elevated salinities. Although commonly used by recent researchers, measurements of Colorado River water crossing the border into Mexico do not provide a reliable proxy for how much water (if any) actually reaches the Upper Gulf because of the complex nature of internal basins and diversions in the region. (C) 2016 Elsevier B.V. All rights reserved.

Hastings, PA, Conway KW.  2017.  Gobiesox lanceolatus, a new species of clingfish (Teleostei: Gobiesocidae) from Los Frailes submarine canyon, Gulf of California, Mexico. Zootaxa. 4221:393-400.   10.11646/zootaxa.4221.3.8   AbstractWebsite

Gobiesox lanceolatus is described from a single specimen collected from 300 meters depth in the Los Frailes submarine canyon in the southwestern Gulf of California. The "Canyon Clingfish" is unique within Gobiesox in having a lanceolate caudal fin, with the central rays longer than those above and below them. It is also distinguished by 14 dorsal-fin rays (first tiny and unsegmented), 11 anal-fin rays, 28 pectoral-fin rays, anus slightly closer to anal-fin origin than to posterior margin of pelvic disc, and dorsal-fin origin in front of vertical from anus. It is most similar to Gobiesox eugrammus, known from Isla Guadelupe, the coast of outer Baja California and southern California. This is the deepest record for a species of Gobiesox and only four other species of clingfishes are known from greater depths.

Conway, KW, Daemin K, Rüber L, Pérez EHS, Hastings PA.  2017.  Molecular systematics of the New World clingfish genus Gobiesox (Teleostei: Gobiesocidae) and the origin of a freshwater clade. . Molecular Phylogenetics and Evolution. 112:138–147.
Huang, W, Hongjamrassilp W, Jung J, Hastings PA, Lubarda VA, McKittrick J.  2017.  Structure and mechanical implications of the pectoral fin skeleton in the Longnose Skate (Chondrichthyes, Batoidea).. Acta Biomaterialia . 51:393-407.
Nosal, AP, Keenan EA, Hastings PA, Gneezy A.  2016.  The effect of background music in shark documentaries on viewers' perceptions of sharks. PLoS ONE. 11:e0159279.: Public Library of Science   10.1371/journal.pone.0159279   AbstractWebsite

Despite the ongoing need for shark conservation and management, prevailing negative sentiments marginalize these animals and legitimize permissive exploitation. These negative attitudes arise from an instinctive, yet exaggerated fear, which is validated and reinforced by disproportionate and sensationalistic news coverage of shark ‘attacks’ and by highlighting shark-on-human violence in popular movies and documentaries. In this study, we investigate another subtler, yet powerful factor that contributes to this fear: the ominous background music that often accompanies shark footage in documentaries. Using three experiments, we show that participants rated sharks more negatively and less positively after viewing a 60-second video clip of swimming sharks set to ominous background music, compared to participants who watched the same video clip set to uplifting background music, or silence. This finding was not an artifact of soundtrack alone because attitudes toward sharks did not differ among participants assigned to audio-only control treatments. This is the first study to demonstrate empirically that the connotative attributes of background music accompanying shark footage affect viewers’ attitudes toward sharks. Given that nature documentaries are often regarded as objective and authoritative sources of information, it is critical that documentary filmmakers and viewers are aware of how the soundtrack can affect the interpretation of the educational content.

Cartamil, D, Wraith J, Wegner NC, Kacev D, Lam CH, Santana-Morales O, Sosa-Nishizaki O, Escobedo-Olvera M, Kohin S, Graham JB, Hastings P.  2016.  Movements and distribution of juvenile common thresher sharks Alopias vulpinus in Pacific coast waters of the USA and Mexico. Marine Ecology Progress Series. 548:153-163.   10.3354/meps11673   AbstractWebsite

The common thresher shark Alopias vulpinus constitutes an important commercial fishery on the Pacific coasts of both the USA and Mexico. However, little is known about the juvenile phase of this species. This study used a combination of pop-up archival satellite tagging, tag-recapture, and fishery catch data to investigate the movement patterns, habitat preferences, ecology, and geographic distribution of juvenile common thresher sharks along the Pacific coast of the USA and Mexico. Juvenile threshers primarily utilized continental shelf waters, with a geographic range extending from Punta Eugenia in Baja California, Mexico (27.8 degrees N) north to Morro Bay, California (35.3 degrees N). Within this range, sharks were found at significantly lower latitudes in March and April. Satellite-tagged juvenile threshers exhibited diel patterns of vertical distribution, primarily inhabiting the upper 20 m of the water column by night, and significantly greater depths by day. In addition, juvenile threshers made frequent daytime dives to depths exceeding 50 m, with a maximum recorded dive depth of 192 m. Tracked sharks were most commonly associated with ambient water temperatures between 14 and 17 degrees C, and inhabited significantly warmer temperatures at night than during the day. No tidal or lunar influence on vertical distribution was found, and vertical habitat utilization did not increase concomitantly with shark size. This study is the first to document movements of juvenile threshers between US and Mexican waters, highlighting the need for bi-national management strategies for this shared fishery resource.

Miller, EC, Lin HC, Hastings PA.  2016.  Improved resolution and a novel phylogeny for the Neotropical triplefin blennies (Teleostei: Tripterygiidae). Molecular Phylogenetics and Evolution. 96:70-78.   10.1016/j.ympev.2015.12.003   AbstractWebsite

The triplefin blennies (Teleostei: Tripterygiidae) are a diverse group of small-bodied benthic fishes associated with rocky or coral reefs. The Neotropics contain four genera and 26 species, many of which have only been recently described. A recent molecular phylogeny (Lin and Hastings, 2013) contrasts with previous phylogenies based on morphology in recovering the four Neotropical genera as a single Glade with respect to the Indo-Pacific genera; however, relationships within and among genera were poorly resolved. This study reports a novel topology based on an expanded seven-loci molecular dataset. Individual gene trees have poor resolution, but concatenated analyses show strong support for most nodes, likely due to emergent support from concatenation. Consistent with Lin and Hastings (2013), three of the Neotropical genera, Axoclinus, Enneanectes, and Crocodilichthys, form a well-supported Glade, but relationships of the fourth (Lepidonectes) are not confidently resolved. The monophyly of Axoclinus is well supported, but Enneanectes is paraphyletic with the inclusion of Axoclinus and Crocodilichthys. Improved resolution allows for reinterpretation of the biogeography of the Neotropical Tripterygiidae. Broader taxon sampling is still necessary for resolving the relationships within Tripterygiidae globally. (C) 2015 Elsevier Inc. All rights reserved.

Galvan-Villa, CM, Rios-Jara E, Bastida-Izaguirre D, Hastings PA, Balart EF.  2016.  Annotated checklist of marine fishes from the Sanctuary of Bahia Chamela, Mexico with occurrence and biogeographic data. Zookeys. :139-157.   10.3897/zookeys.554.6106   AbstractWebsite

An annotated checklist of marine fishes of the Sanctuary of Islands and Islets of Bahia Chamela in the central Mexican Pacific is presented. Records of fish species were obtained by different methods including visual census, sampling with anesthetics, fisherman-nets, and trawling with a biological dredge. Additional records were obtained from natural history collections and publications. The list comprises 196 species in 64 families and 141 genera. The Carangidae is the most speciose family with 11 species, followed by the Labridae with 10 and the Pomacentridae with nine. Fourteen species are endemic in Mexican Pacific waters, but none is restricted to Bahia Chamela. The most dominant species recorded during underwater surveys were Epinephelus labriformis, Stegastes flavilatus, and Halichoeres dispilus. Most species are of tropical affinities distributed throughout the tropical eastern Pacific (123), eastern Pacific (23), and Mexican Pacific (14). Other species are known from the eastern and Indo-Pacific regions (18), eastern Pacific and western Atlantic oceans (2), and some are circumtropical (9). A new record of the Gulf Brotula Ogilbia ventralis is provided for the Bahia Chamela and its geographical distribution is extended to Mexican central Pacific.

Nosal, AP, Chao Y, Farrara JD, Chai F, Hastings PA.  2016.  Olfaction contributes to pelagic navigation in a coastal shark. Plos One. 11   10.1371/journal.pone.0143758   AbstractWebsite

How animals navigate the constantly moving and visually uniform pelagic realm, often along straight paths between distant sites, is an enduring mystery. The mechanisms enabling pelagic navigation in cartilaginous fishes are particularly understudied. We used shoreward navigation by leopard sharks (Triakis semifasciata) as a model system to test whether olfaction contributes to pelagic navigation. Leopard sharks were captured along-shore, transported 9 km offshore, released, and acoustically tracked for approximately 4 h each until the transmitter released. Eleven sharks were rendered anosmic (nares occluded with cotton wool soaked in petroleum jelly); fifteen were sham controls. Mean swimming depth was 28.7 m. On average, tracks of control sharks ended 62.6% closer to shore, following relatively straight paths that were significantly directed over spatial scales exceeding 1600 m. In contrast, tracks of anosmic sharks ended 37.2% closer to shore, following significantly more tortuous paths that approximated correlated random walks. These results held after swimming paths were adjusted for current drift. This is the first study to demonstrate experimentally that olfaction contributes to pelagic navigation in sharks, likely mediated by chemical gradients as has been hypothesized for birds. Given the similarities between the fluid three-dimensional chemical atmosphere and ocean, further research comparing swimming and flying animals may lead to a unifying paradigm explaining their extraordinary navigational abilities.

Love, MS, Passarelli JK, Cantrell B, Hastings PA.  2016.  The Largemouth Blenny, Labrisomus xanti, New to the California Marine Fauna with a List of and Key to the Species of Labrisomidae, Clinidae, and Chaenopsidae found in California Waters. . Bulletin of the Southern California Academy of Sciences . 115:191-196.
Hastings, PA, Širović A.  2015.  Soundscapes offer unique opportunities for studies of fish communities. Proceedings of the National Academy of Sciences. 112:5866-5867.   10.1073/pnas.1505897112   Abstract

Resource partitioning is a fundamental ecological concept in which cooccurring species reduce competition by using or specializing on different resources (1). It is widely accepted as a mechanism permitting similar species to cooccur, leading to increased levels of species diversity (2). Typically, resources are thought of as food, habitat, or behavioral features such as timing of foraging and pattern of prey capture. However, the concept applies equally well to any niche parameter that affects species success. This includes the “space” to effectively communicate with conspecifics (3). In PNAS, Ruppé et al. (4) document apparent resource partitioning in the acoustic communication behavior of a community of nocturnal marine fishes found in a cave environment on the rocky coastline of South Africa. They recorded and analyzed 2,793 instances of 17 distinctive sounds that differed in peak frequency and pulsing characteristics. They assumed those distinctive sounds represent separate species and found that sounds from sonic species recorded during the day were less acoustically distinct from one another than those recorded at night. The authors interpret this pattern as indicative of resource partitioning among nocturnal species that are largely limited to acoustic communication modalities. In contrast, the acoustic signals of diurnal species in the same community, for which visual displays undoubtedly play a larger role, are not so constrained and overlap considerably in frequency at the resolution used in their analysis (∼700 Hz).

Hastings, PA, Findley LT.  2015.  Chriolepis prolata, a new species of Atlantic goby (Teleostei: Gobiidae) from the North American continental shelf. Zootaxa. 3904:589-595.   10.11646/zootaxa.3904.4.8   Abstract

A new species of seven-spined goby of the genus Chriolepis is described from five specimens collected from the continental shelf of the northeastern Gulf of Mexico and Atlantic Ocean off South Carolina in depths of ca 54 to 110 m. The "Platform Goby", Chriolepis prolata, is distinguishable from all other western Atlantic species currently assigned to the genus Chriolepis and the morphologically similar genus Varicus in having pelvic-fin rays one through four branched, the fifth (innermost) pelvic-fin ray unbranched and relatively long (longer than the second ray to longer than all other pelvic-fin rays); most lateral body scales ctenoid, extending anteriorly in a wedge to a level anterior to the first dorsal-fin insertion or nearly to the pectoral-fin axil, with two or more rows of small cycloid scales extending anteriorly to near the pectoral-fin axil, cycloid scales along the bases of the dorsal and anal fins, and no scales on the belly; and the first two anal-fin pterygiophores inserted anterior to the first haemal spine. It closely resembles C. bilix but differs from that species which has a scaled belly, a shorter fifth pelvic-fin ray, prolonged dorsal-fin spines and smaller teeth in the lower jaw. An earlier report of C. bilix from Florida waters apparently refers to C. prolata.

Hastings, PA, Craig MT, Erisman BE, Hyde JR, Walker HJ.  2014.  Fishes of marine protected areas near La Jolla, California. Bulletin of the Southern California Academy of Sciences. 113(3):200-231. Abstract

The marine waters surrounding La Jolla, California have a diverse array of habitats and include several marine protected areas (MPAs). We compiled a list of the fish species occurring in the vicinity based on records of specimens archived in the Marine Vertebrate Collection (MVC) of the Scripps Institution of Oceanography (SIO). Collection of fishes from La Jolla in the MVC started in 1905, but greatly accelerated in 1944 when Carl L. Hubbs moved to SIO. By 1964, 90% of the 265 species recorded from the area had been collected and archived in the MVC. The fishes of La Jolla are dominated by species whose center of distribution is north of Point Conception (111 species), or between there and Punta Eugenia (96), with fewer species with southern distributions (57), and one exotic species. Reflecting the diversity of habitats in the area, soft-substrate species number 135, pelagic species 63, canyon-dwelling species 123 (including 35 rockfish species of the genus Sebastes),and hard-bottom species 140. We quantified the abundance of the latter group between 2002 and 2005 by counting visible fishes in transects along the rocky coastline of La Jolla, both within and adjacent to one of the region’s MPAs. In 500 transects, we counted over 90,000 fishes representing 51 species. The fish communities inside and outside of the MPA were similar and, typical of southern California kelp forests, numerically dominated by Blacksmith, Chromis punctipinnis (Pomacentridae), and Señorita, Oxyjulis californica (Labridae). Natural history collections such as the MVC are important resources for conservation biology for determining the faunal composition of MPAs and surrounding habitats, and documenting both the disappearance and invasion of species.

Hastings, PA, Walker HJ, Galland GR.  2014.  Fishes: A Guide To Their Diversity. , Oakland: University of California Press Abstract

There are more than 33,000 species of living fishes, accounting for more than half of the extant vertebrate diversity on Earth. This unique and comprehensive reference showcases the basic anatomy and diversity of all 82 orders of fishes and more than 150 of the most commonly encountered families, focusing on their distinctive features.Accurate identification of each group, including its distinguishing characteristics, is supported with clear photographs of preserved specimens, primarily from the archives of the Marine Vertebrate Collection at Scripps Institution of Oceanography. This diagnostic information is supplemented by radiographs, additional illustrations of particularly diverse lineages, and key references and ecological information for each group.An ideal companion to primary ichthyology texts,Fishes: A Guide to Their Diversity gives a broad overview of fish morphology arranged in a modern classification system for students, fisheries scientists, marine biologists, vertebrate zoologists, and everyday naturalists. This survey of the most speciose group of vertebrates on Earth will expand the appreciation of and interest in the amazing diversity of fishes.

Fishelson, L, Baldwin CC, Hastings PA.  2013.  Gonad morphology, gametogenesis, and reproductive modes in fishes of the tribe starksiini(Teleostei, Blenniiformes). Journal of Morphology. 274:496-511.   10.1002/jmor.20110   AbstractWebsite

A comparative study of the reproductive organs in 17 of the 30 species of the tribe Starksiini (Labrisomidae, Blenniiformes) and related labrisomids reveals the major traits of gamete form and production and likely reproductive modes. The testes are of the lobular type and have a testicular gland and sperm ducts. Isodiametric sperm (aquasperm) with a globular head or anisodiametric sperm (introsperm) with an elongate head, or both, were observed in the studied species. Both types have either one or two flagella in the sperm tail. Ovaries of the Starksiini are bilobed and exhibit synchronous or asynchronous egg production. Although viviparity or ovoviviparity reportedly characterizes the group, our study revealed evidence of both internal and external fertilization and three modes of reproduction. External fertilization or ovuliparity is suggested for the Starksia atlantica and S. lepicoelia species complexes by the presence in males of a short genital papilla that is not !

Rife, AN, Aburto-Oropeza O, Hastings PA, Erisman B, Ballantyne F, Wielgus J, Sala E, Gerber L.  2013.  Long-term effectiveness of a multi-use marine protected area on reef fish assemblages and fisheries landings. Journal of Environmental Management. 117:276-283.   10.1016/j.jenvman.2012.12.029   AbstractWebsite

The Loreto Bay National Park (LBNP) is a large, multi-use marine protected area in the Gulf of California, Mexico, where several types of small-scale commercial and recreational fishing are allowed, but where less than 1% of the park is totally protected from fishing. The LBNP was created in 1996; its management plan was completed in 2000, but it was not effectively implemented and enforced until 2003. Between 1998 and 2010, we monitored reef fish populations annually at several reefs inside and outside the LBNP to measure the effects of the park on fish assemblages. We also evaluated reported fisheries landings within the LBNP for the same time series. Our results show that reef fish biomass increased significantly after protection at a small no-take site at LBNP relative to the rest of the park. However, the multi-use part of LBNP where fishing is allowed (99% of its surface) has had no measurable effect on reef fish biomass relative to open access sites outside the park boundaries. Reported fisheries landings have decreased within the park while increasing in nearby unprotected areas. Although the current partial protection management regime has not allowed for reef fish populations to recover despite 15 years as a "protected area," we conclude that LBNP's regulations and management have maintained the conditions of the ecosystem that existed when the park was established. These results suggest that community livelihoods have been sustained, but a re-evaluation of the multi-use management strategy, particularly the creation of larger no-take zones and better enforcement, is needed to improve the reef fish populations in the park in order to ensure sustainable fisheries far into the future. These recommendations can be applied to all multi-use MPAs in Mexico where ecosystem recovery is not occurring despite maintenance of fish stocks. (C) 2013 Elsevier Ltd. All rights reserved.

Rosenblatt, RH, Miller EC, Hastings PA.  2013.  Three new species of triplefin blennies of the genus Enneanectes (Teleostei, Tripterygiidae) from the tropical eastern Pacific with a key to Pacific species of Enneanectes. Zootaxa. 3636:361-373. AbstractWebsite

Three new species of the triplefin blenny genus Enneanectes found in the Pacific Ocean off southern Mexico are described. Two, Enneanectes glendae and Enneanectes macrops, are mainland species, while the third, Enneanectes exsul, is endemic to the Islas Revillagigedo. A key to the five species of Enneanectes known from the tropical eastern Pacific is provided.

Lin, HC, Hastings PA.  2013.  Phylogeny and biogeography of a shallow water fish clade (Teleostei: Blenniiformes). Bmc Evolutionary Biology. 13 AbstractWebsite

Background: The Blenniiformes comprises six families, 151 genera and nearly 900 species of small teleost fishes closely associated with coastal benthic habitats. They provide an unparalleled opportunity for studying marine biogeography because they include the globally distributed families Tripterygiidae (triplefin blennies) and Blenniidae (combtooth blennies), the temperate Clinidae (kelp blennies), and three largely Neotropical families (Labrisomidae, Chaenopsidae, and Dactyloscopidae). However, interpretation of these distributional patterns has been hindered by largely unresolved inter-familial relationships and the lack of evidence of monophyly of the Labrisomidae. Results: We explored the phylogenetic relationships of the Blenniiformes based on one mitochondrial (COI) and four nuclear (TMO-4C4, RAG1, Rhodopsin, and Histone H3) loci for 150 blenniiform species, and representative outgroups (Gobiesocidae, Opistognathidae and Grammatidae). According to the consensus of Bayesian Inference, Maximum Likelihood, and Maximum Parsimony analyses, the monophyly of the Blenniiformes and the Tripterygiidae, Blenniidae, Clinidae, and Dactyloscopidae is supported. The Tripterygiidae is the sister group of all other blennies, and the Blenniidae is the sister group of the remaining blennies. The monophyly of the Labrisomidae is supported with the exclusion of the Cryptotremini and inclusion of Stathmonotus, and we elevate two subgenera of Labrisomus to establish a monophyletic classification within the family. The monophyly of the Chaenopsidae is supported with the exclusion of Stathmonotus (placed in the Stathmonotini) and Neoclinus and Mccoskerichthys (placed in the Neoclinini). The origin of the Blenniiformes was estimated in the present-day IndoPacific region, corresponding to the Tethys Sea approximately 60.3 mya. A largely Neotropical lineage including the Labrisomidae, Chaenopsidae and Dactyloscopidae (node IV) evolved around 37.6 mya when the Neotropics were increasingly separated from the IndoPacific, but well before the closure of the Tethys Sea. Conclusions: Relationships recovered in this study are similar to those of earlier analyses within the Clinidae and Chaenopsidae, and partially similar within the Blenniidae, but tripterygiid relationships remain poorly resolved. We present the first comprehensive phylogenetic hypothesis for a monophyletic Labrisomidae with five tribes (Labrisomini, Mnierpini, Paraclinini, Stathmonotini and Starksiini). Global distributions of blenny genera included in our analysis support the evolution of a largely Neotropical clade whose closest relatives (clinids and cryptotremines) are temperate in distribution.

Hastings, PA, Findley LT.  2013.  Chriolepis bilix, a new species of goby (Teleostei: Gobiidae) from deep waters of the western Atlantic. Zootaxa. 3745:596-600. AbstractWebsite

A new species of seven-spined goby of the genus Chriolepis is described from four specimens from four widely separate western Atlantic localities (Little Bahama Bank; off southwestern Florida; Tobago Island; and northeastern Colombia) from depths ranging from 62 to 138 m. The species is distinct from all other western Atlantic species currently assigned to the genus Chriolepis in having a fully scaled body, the first two dorsal-fin spines greatly elongated in both sexes, especially so in females, and two anal-fin pterygiophores inserted anterior to the first haemal spine. It differs from members of the similar genus Varicus in having branched pelvic-fins rays, a longer fifth pelvic-fin ray and more numerous meristic elements. It closely resembles Chriolepis atrimelum, known from a similar depth at Isla del Coco in the eastern Pacific Ocean.

Erisman, BE, Petersen CW, Hastings PA, Warner RR.  2013.  Phylogenetic perspectives on the evolution of functional hermaphroditism in teleost fishes. Integrative and Comparative Biology. 53:736-754.   10.1093/icb/ict077   AbstractWebsite

Hermaphroditism is taxonomically widespread among teleost fishes and takes on many forms including simultaneous, protogynous, and protandrous hermaphroditism, bidirectional sex change, and androdioecy. The proximate mechanisms that influence the timing, incidence, and forms of hermaphroditism in fishes are supported by numerous theoretical and empirical studies on their mating systems and sexual patterns, but few have examined aspects of sex-allocation theory or the evolution of hermaphroditism for this group within a strict phylogenetic context. Fortunately, species-level phylogenetic reconstructions of the evolutionary history of many lineages of fishes have emerged, providing opportunities for understanding fine-scale evolutionary pathways and transformations of sex allocation. Examinations of several families of fishes with adequate data on phylogeny, patterns of sex allocation, mating systems, and with some form of hermaphroditism reveal that the evolution and expression of protogyny and other forms of sex allocation show little evidence of phylogenetic inertia within specific lineages but rather are associated with particular mating systems in accordance with prevalent theories about sex allocation. Transformations from protogyny to gonochorism in groupers (Epinephelidae), seabasses (Serranidae), and wrasses and parrotfishes (Labridae) are associated with equivalent transformations in the structure of mating groups from spawning of pairs to group spawning and related increases in sperm competition. Similarly, patterns of protandry, androdioecy, simultaneous hermaphroditism, and bidirectional sex change in other lineages (Aulopiformes, Gobiidae, and Pomacentridae) match well with particular mating systems in accordance with sex-allocation theory. Unlike other animals and plants, we did not find evidence that transitions between hermaphroditism and gonochorism required functional intermediates. Two instances in which our general conclusions might not hold include the expression of protandry in the Sparidae and the distribution of simultaneous hermaphroditism. In the Sparidae, the association of hypothesized mating systems and patterns of sex allocation were not always consistent with the size-advantage model (SAM), in that certain protandric sparids show evidence of intense sperm competition that should favor the expression of gonochorism. In the other case, simultaneous hermaphroditism does not occur in some groups of monogamous fishes, which are similar in ecology to the hermaphroditic serranines, suggesting that this form of sex allocation may be more limited by phylogenetic inertia. Overall, this work strongly supports sexual lability within teleost fishes and confirms evolutionary theories of sex allocation in this group of vertebrates.

Fishelson, L, Baldwin CC, Hastings PA.  2012.  Comparison of the oropharyngeal cavity in the Starksiini (Teleostei: Blenniiformes: Labrisomidae): Taste buds and teeth, including a comparison with closely-related genera. Journal of Morphology. 273:618-628.   10.1002/jmor.20008   AbstractWebsite

The present study describes the distribution of taste buds and teeth in the oropharyngeal cavity of 13 species of adult (18-60 mm SL) Starksiini fishes inhabiting subtidal waters of the Neotropical region. Four types of taste buds described previously in other fish groups were observed within the oropharyngeal cavity, of which type I, situated on prominent protruding papillae, is the most common. The number of taste buds in this cavity varies considerably, ranging from ca. 202 in Starksia lepicoelia to ca. 770 in S. sluiteri. In all the studied species, taste buds are more numerous on the posterior (160-396) than on the anterior (42-294) part of the oropharyngeal cavity. The presence of different numbers of taste buds in different Starksiini species of the same standard length suggests that numbers of taste buds are not directly correlated with size and may be species-specific. Teeth are found on the premaxilla, dentary, vomer, palatine (in some species) and the upper and lower pharyngeal jaws (third pharyngobranchials and fifth ceratobranchials, respectively); the form and number of teeth and taste buds on each of these sites differs among the various species of Starksiini and between them and closely related species of the labrisomid tribes Labrisomini, Mnierpini, and Paraclinini. The results thus suggest potential systematic value in certain features of the oropharyngeal cavity for blenniiform fishes. It is also shown that benthic-feeding omnivorous fishes have higher densities of taste buds than piscivorous fishes. A possible correlation among numbers of taste buds, their positions in the oropharyngeal cavity, and other parameters is discussed. J. Morphol., 2012. (C) 2012 Wiley Periodicals, Inc.

Eytan, RI, Hastings PA, Holland BR, Hellberg ME.  2012.  Reconciling molecules and morphology: Molecular systematics and biogeography of Neotropical blennies (Acanthemblemaria). Molecular Phylogenetics and Evolution. 62:159-173.   10.1016/j.ympev.2011.09.028   AbstractWebsite

Neotropical reef fish communities are species-poor compared to those of the Indo-West Pacific. An exception to that pattern is the blenny clade Chaenopsidae, one of only three rocky and coral reef fish families largely endemic to the Neotropics. Within the chaenopsids, the genus Acanthemblemaria is the most species-rich and is characterized by elaborate spinous processes on the skull. Here we construct a species tree using five nuclear markers and compare the results to those from Bayesian and parsimony phylogenetic analyses of 60 morphological characters. The sequence-based species tree conflicted with the morphological phylogenies for Acanthemblemaria, primarily due to the convergence of a suite of characters describing the distribution of spines on the head. However, we were able to resolve some of these conflicts by performing phylogenetic analyses on suites of characters not associated with head spines. By using the species tree as a guide, we used a quantitative method to identify suites of correlated morphological characters that, together, produce the distinctive skull phenotypes found in these fishes. A time calibrated phylogeny with nearly complete taxon sampling provided divergence time estimates that recovered a mid-Miocene origin for the genus, with a temporally and geographically complex pattern of speciation both before and after the closure of the Isthmus of Panama. Some sister taxa are broadly sympatric, but many occur in allopatry. The ability to infer the geography of speciation in Acanthemblemaria is complicated by extinctions, incomplete knowledge of their present geographic ranges and by wide-spread taxa that likely represent cryptic species complexes. (C) 2011 Elsevier Inc. All rights reserved.