Revision of the 'dragon-head' cusk eels of the genus Porogadus (Teleostei: Ophidiidae), with description of eight new species and one new genus

The ophidiid genus Porogadus occurs between 800 and 5300 m in the tropical and subtropical world oceans. Fifteen nominal species have been described since 1878 and most of them until 1902. The genus has been highlighted as needing revision in recent compilations about ophidiiforms and here we present the first comprehensive review. Twelve of the previously described species are here accepted as valid with two being moved to the newly established genus Tenuicephalus n. gen. that encompasses fishes differing from those of Porogadus in the extremely weak ossification, the stout head, absence of head spines and absence of the “triple” lateral line system considered typical for Porogadus and a reduced dentition. In addition, eight new species are described: Porogadus caboverdensis, P. dracocephalus, P. lacrimatus, P. mendax, P. solomonensis, P. turgidus, Tenuicephalus multitrabs and T. squamilabrus. The species of Porogadus show a distinctive depth segregation with the majority of species having a demersal bathyal life-style between 800 and 3500 m and other species being more or less exclusively restricted to abyssal depths below 3000 m. The biogeographic distribution pattern of bathyal groups shows putative species pairs in the Atlantic versus the eastern Pacific and a clear separation of eastern Pacific from Indo-West Pacific species. The geographic effects and timing are being discussed that may have led to this speciation events. Generally, we found widely distributed species that are found far away from continental masses and others restrained to continental slopes and sometimes exhibiting regionalism. In abyssal depth, the Cabo Verde and Canary basins off NW-Africa have yielded three exclusive species, but it is uncertain at this stage whether this could represent a sampling bias with this area being extensively sampled by the Discovery research vessel (BMNH) over the years from 1970–1998. Another instance of a potentially endemic abyssal species is that of Porogadus melanocephalus in the Bay of Bengal. The latter has been caught with 45 specimens in a single trawl, representing the highest number of Porogadus specimens collected in any trawl and indicating that these fishes may actually not be as rare as one might assume from the literature

A late santonian fish-fauna from the eutaw formation of Alabama reconstructed from otoliths

The otoliths described here from the Late Santonian of the Eutaw Formation of Alabama, represent one of the earliest association of teleost otoliths known from North America and it is remarkable for its good preservation and species diversity. They were collected by the late C.K. Lamber in 1969 from a road cut on the Hurtsboro-Marvyn highway south of Marvyn in Russell County, eastern Alabama. It contains 18 taxa based on sagittae otoliths, of which 14 are identifiable to the species level, 10 species are new to science and five new genera. The new otolith-based genera are: Allogenartina n. gen. (Stomiiformes family indet.), Pseudotrichiurus n. gen. (Aulopiformes family indet.), Eutawichthys n. gen. (Beryciformes family indet.), Cowetaichthys n. gen. (Polymixiidae) and Vox n. gen. (Teleostei family indet.); the new species are: Elops eutawanus n. sp., Genartina cretacea n. sp., Allogenartina muscogeei n. sp., Pseudotrichiurus sagax n. sp., Apateodus? assisi n. sp., Eutawichthys compressus n. sp., Eutawichthys stringeri n. sp., Cowetaichthys alabamae n. sp., Cowetaichthys lamberi n. sp. and Vox thlotlo n. sp. In addition, 8 different morphologies are recognized based on lapilli otoliths, which however cannot be identified to a distinct taxonomic level except for a species of the Ariidae. Two taxa can be related to otoliths recently recorded in situ, pertaining to the genera Osmeroides and Apateodus. The otolith association bears much similarity with those of the Campanian to Maastrichtian of the USA described previously as indicated by the dominance of otoliths of the genera Eutawichthys and Osmeroides. Differences with those faunas are on the species level as well as in the accessory components. The abundance of otoliths of the albuliforms (Osmeroides), putative stomiiforms (Allogenartina), beryciform (Eutawichthys) and polymixiids (Cowetaichthys) characterizes a rather stable faunal composition through the entire Late Cretaceous of locations studied in the USA. The conundrum of interpreting the systematic position of isolated Late Cretaceous otoliths is discussed and the findings are correlated with the rich fish fauna known from articulated skeletons of the coeval Niobrara Formation. We consider the taxonomic position of the majority of isolated otoliths to be more or less consistent with the skeletal findings, but there are also a few otolith morphologies, which do not seem to have a skeletal equivalent in the Niobrara Formation, e.g. in osteoglossiforms, clupeiforms, stomiiforms and Ariidae

Fish otoliths from the middle Miocene Pebas Formation of the Peruvian Amazon

A small assemblage of 22 otoliths was identified from the historical collection of Bluntschli and Peyer gathered in 1912 on the Itaya riverbank at Iquitos, Peru (Amazonia), from the Pebas Formation. The Pebas Mega-Wetland System in western Amazonia during the Miocene represented a unique, albeit short-lived, biotope characterized by a pronounced endemic evolution with gigantism in some vertebrate groups (e.g., turtles, crocodylians). Thus far, fishes have mainly been recorded based on isolated skeletal remains and teeth. Here, we describe the first well-preserved otolith assemblage from the Pebas Formation. This otolith assemblage adds a new facet to the fauna by complementing the skeletal bony fish data, primarily with species of the Sciaenidae and, to a lesser extent, Ariidae and Cichlidae. The sciaenids and ariids indicate that migration must have occurred between the marginal marine environments to the north and the Pebas Wetland System. The otoliths also indicate the likelihood of endemic developments of adapted marine immigrants to the Pebas Wetland System, some of which have become extinct (Pogonias, Umbrina), while others now represent typical South American freshwater fish groups (Plagioscion). Six new species are described based on otoliths, one in the Cichlidae—Cichlasoma bluntschlii n. sp., one in the Ariidae—Cantarius ohei n. sp., and four in the Sciaenidae—Pebasciaena amazoniensis n. gen. et n. sp., Plagioscion peyeri n. sp., Pogonias tetragonus n. sp. and Umbrina pachaula n. sp

Fish remains, mostly otoliths, from the non-marine early Miocene of Otago, New Zealand

Fish remains described from the early Miocene lacustrine Bannockburn Formation of Central Otago, New Zealand, consist of several thousand otoliths and one skeleton plus another disintegrated skull. One species, Mataichthys bictenatus Schwarzhans, Scofield, Tennyson, and T. Worthy gen. et sp. nov., an eleotrid, is established on a skeleton with otoliths in situ. The soft embedding rock and delicate, three−dimensionally preserved fish bones were studied by CT−scanning technology rather than physical preparation, except where needed to extract the otolith. Fourteen species of fishes are described, 12 new to science and two in open nomenclature, representing the families Galaxiidae (Galaxias angustiventris, G. bobmcdowalli, G. brevicauda, G. papilionis, G. parvirostris, G. tabidus), Retropinnidae (Prototroctes modestus, P. vertex), and Eleotridae (Mataichthys bictenatus, M. procerus, M. rhinoceros, M. taurinus). These findings prove that most of the current endemic New Zealand/southern Australia freshwater fish fauna was firmly established in New Zealand as early as 19–16 Ma ago. Most fish species indicate the presence of large fishes, in some cases larger than Recent species of related taxa, for instance in the eleotrid genus Mataichthys when compared to the extant Gobiomorphus. The finding of a few otoliths from marine fishes corroborates the age determination of the Bannockburn Formation as the Altonian stage of the New Zealand marine Tertiary stratigraphy.Werner Schwarzhans, R. Paul Scofield, Alan J.D. Tennyson, Jennifer P. Worthy, and Trevor H. Worth

Fish otoliths from the middle Paleocene (Selandian) of southern Sweden

The first fossil otolith association from the middle Paleocene (Selandian) of Scania, southern Sweden is described. Forty-seven otoliths were retrieved from shallow wells representing 14 teleost taxa. Many specimens are small and/or eroded and, therefore, not identifiable to species level. Nevertheless, our findings indicate the potential for further fossil otolith discoveries in the region. The Scanian otolith-based fauna greatly resembles the better-known coeval association from Copenhagen, Denmark, but is relatively rich and diverse in perciform otoliths. The fauna records the first occurrence of Serranus? caribbaeus from the European Paleocene, and of Archaemacruroides ornatus from the Selandian of the North Sea Basin

Otoliths of the Gobiidae from the Neogene of tropical America

Abstract Otoliths are common and diverse in the Neogene of tropical America. Following previous studies of Neogene tropical American otoliths of the lanternfishes (Myctophidae), marine catfishes (Ariidae), croakers (Sciaenidae), and cusk-eels (Ophidiiformes), we describe here the otoliths of the gobies (Gobiidae). The Gobiidae represent the richest marine fish family, with more than 2000 species worldwide and about 250 in America. In the fossil record too they are the species richest family in the Neogene of tropical America. We have investigated otoliths sampled from Ecuador, Pacific and Atlantic Panama, Atlantic Costa Rica, Dominican Republic, Venezuela, and Trinidad, ranging in age from late Early Miocene (late Burdigalian) to late Early Pleistocene (Calabrian). Most of the studied material originates from the collection expeditions of the Panama Paleontology Project (PPP). Our study represents the first comprehensive record of fossil gobies from America, and we recognize 107 species, of which 51 are new to science, 35 are in open nomenclature, and 19 represent species that also live in the region today. Previously, only two fossil otolith-based goby species have been described from the Neogene of tropical America. The dominant gobies in the fossil record of the region are from the Gobiosomatini, particularly of genera living over soft bottoms or in deeper water such as Bollmannia, Microgobius, Antilligobius, and Palatogobius. Another purpose of our study is to provide a first comprehensive account of otoliths of the extant Gobiidae of America, which we consider necessary for an adequate identification and interpretation of the Neogene otoliths. We studied otoliths of 130 extant American gobiid species and figured 106 of them for comparison. We also present a morphological analysis and characterization of the extant otoliths as a basis for the identification of fossil otoliths. Problems that commonly arise with the identification of fossil otoliths and specifically of fossil goby otoliths are addressed and discussed. A comparison of the history of the Gobiidae in tropical America reveals a high percentage of shared species between the Pacific and the Atlantic basins during the Late Miocene (Tortonian and Messinian) from at least 11 to 6 Ma. A recording gap on the Pacific side across the Pliocene allows a comparison again only in the late Early Pleistocene (Calabrian, 1.8 to 0.78 Ma), which shows a complete lack of shared species. These observations support the effective closure of the former Central American Seaway and emersion of the Isthmus of Panama in the intervening time. Groups that today only exist in the East Pacific were also identified in the Miocene and Pliocene of the West Atlantic, and there is also at least one instance of a genus now restricted to the West Atlantic having occurred in the East Pacific as late as the Pleistocene. The evolution of gobies in tropical America and the implications thereof are extensively discussed. Furthermore, observations of fossil gobies in the region are discussed in respect to paleoenvironmental indications and paleobiogeographic aspects

Porogadus abyssalis Nybelin 1957

Porogadus abyssalis Nybelin, 1957 Figs. 29, 46, 49, Tab. 1–7 Porogadus abyssalis Nybelin, 1957: 288, figs. 19–20, pl.6 figs. 2–4; Nielsen et al. 1999: 86. Material examined (3 specimens): MNHN 1979-0239, 105 mm SL, 10°58’N 43°13’W, 5100 m, Biovema Expedition, Sta. a6/cp01, collected by J. Charcot, 13 November 1977; MNHN 1979-0240, 160 mm SL, 10°58’N 43°13’W, 5100 m, Biovema Expedition, Sta. a6/cp01, collected by J. Charcot, 13 November 1977; MNHN 1992-1231, 158 mm SL, 10°24’N 46°43’W, 4830 m, Demeraby Expedition, Sta. cp14, collected by J. Charcot, 28 September 1980. Diagnosis. Precaudal vertebrae 18–19; long gill rakers on lower part of first gill arch 13–14; pectoral-fin rays 19–23; HL:HD 1.85–2.09; most head spines moderately strong or weak, present on ethmoidal, prefrontal, interorbital, supraorbital, sphenotic, inner preopercular rim; absent on lacrimal, 5th infraorbital, supratemporal, inner and outer posttemporal, outer preopercular rim; opercular spine sharp, extruding; opercular flap small; lower lateral line pores until beginning of anal fin 23; vomer with moderately broad dentition patch with 2–3 rows of teeth; palatines with moderately broad dentition patch 2–4 rows of teeth; otolith with single colliculum; OL:OH = 1.17; OL:TCL = 2.3. Description (based on non-types and holotype data from Nybelin 1957). Meristics: precaudal vertebrae 18–19, 1 last vertebrae without ribs; pectoral-fin rays 19 (19–23); D/V = 6; D/A = 24–27; V/A = 19–21; long gill rakers on lower gill arch 14 (13–14). Gill rakers in a typical specimen (MNHN 1979-0240) on lower first gill arch with six short rakers, followed by a series of 16 long rakers. The lower 8 of those intercept by narrow plate shaped rakers. These are smaller than in most species. Upper gill raker with a series of three semi long rakers and three plate like rakers intercepted, followed by two very short rakers. Morphometrics: in % of SL: HL 16.5 (16.5–17.0); maximal HD 8.2–9.0; HD through center of eye 5.2–6.1; bony interorbital width 3.4–3.6; snout length 6.1; upper jaw length 9.7–10.1; predorsal 17.4–18.4; preanal 33.9 (29.3–33.9); prepelvic 12.2–13.4; prepectoral 16.6–17.4; pectoral length 10.4. Relations: HL:HD = 1.85–2.09; HL to snout length 2.72–2.77; preanal to predorsal 1.68–1.69; predorsal to prepectoral 1.05–1.06. Slender fish with long tapering tail and long, pointed snout. Maximal size of fishes investigated 209 mm SL (holotype). Head long and very slender, with flat dorsal profile, with moderate to weak spines as follows: ethmoidal (1), prefrontal (1 weak), interorbital (3), supraorbital (2 weak), sphenotic (2–3), inner preopercular rim (3–4); no spines on lacrimal, 5th infraorbital, supratemporal, inner and outer posttemporal, outer preopercular rim. Opercle with sharp, short spine. Eye small located in strongly asymmetric orbit. Maxilla extending far beyond eye, strongly widened posteriorly and with distinct supramaxilla. Infra-/postorbital and mandibular-preopercular pores wide, 1 pore on occiput in front of nape. Head squamation on opercle, cheeks and occiput; absent on frontal, around eyes, and on maxilla. Opercle with two distinct large neuromasts behind preopercular edge; opercular flap small, with few radial ridges along lower margin. Lateral line rows rarely well visible and therefore number of pores countable only in rare instances. Lower lateral line row with 23 pores until beginning of anal fin in one specimen. Dentition. All teeth tiny and needle like. Vomer with a narrow dentition patch with 2–3 rows of teeth anteriorly; palatines with a narrow dentition patch with 2–4 rows of teeth in middle part. Premaxilla tooth patches not fused anteriorly; ca. 4 teeth rows anteriorly and 2–3 rows posteriorly. Dentary tooth patches not fused anteriorly; ca. 4 teeth rows anteriorly and a single row posteriorly. Median basibranchial tooth patch very short. Otolith morphology (n = 1). Size 1.8 mm in length (MNHN 1979-0240); OL:OH = 1.17; OH:OT 2.8. Thin, small, compressed, roundish otolith. All rims regularly rounded and smooth. Inner face flat, smooth, with short, centrally positioned sulcus; OL:TCL = 2.3. Sulcus with shallow, undivided, uniform, oval, wide colliculum. Dorsal field with indistinct depression; ventral field with faint ventral furrow. Outer face smooth, without umbo. Coloration. Color of preserved specimens light brown; belly slightly darker, opercle distinctly darker. Live coloration somewhat darker according to Nybelin (1957). Discussion. Porogadus abyssalis was described based on a unique holotype by Nybelin (1957) caught at 5250– 5300 m in the central Atlantic, which then was the deepest catch of any Porogadus specimen which hitherto were caught shallower than 3300 m. The weak head ossification and armature and the small, morphologically simple otolith may reflect adaptation to a deep sea habitat below the CCD. Within the Porogadus gracilis group, Porogadus abyssalis is best recognized by its unusual high number of pectoral-fin rays (19–23 vs 15–18) and some relatively strong spines on the head. With its slender and elongate head and the high number of lower lateral line pores until the beginning of the anal fin P. abyssalis resembles several species of the Porogadus miles group, but differs in the generally much weaker head armature, weaker head ossification and the very small and compressed otoliths. Distribution. The specimens described here are the only other specimens beside the unique holotype described by Nybelin (1957). They confirm the deep sea dwelling of the species in the tropical Atlantic and far away from any shelf break (700–1000 km, Fig. 49) on the abyssal plane near to the middle Atlantic ridge.Published as part of Schwarzhans, Werner W. & Møller, Peter R., 2021, Revision of the ' dragon-head' cusk eels of the genus Porogadus (Teleostei: Ophidiidae), with description of eight new species and one new genus, pp. 1-96 in Zootaxa 5029 (1) on pages 60-62, DOI: 10.11646/zootaxa.5029.1.1, http://zenodo.org/record/545413