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1.
The Indo-Pacific marine atherinid fishes, Atherinomorus endrachtensis (Quoy and Gaimard, 1825) and Atherinomorus duodecimalis (Valenciennes in Cuvier and Valenciennes, 1835), having long been confused with each other, are redescribed as valid species based on the types and nontype specimens collected from the eastern Indian Ocean and West Pacific. Atherinomorus endrachtensis, known from the Philippines, Palau, North Sulawesi and Maluku Is. (Indonesia), and New Guinea, differs from other congeners in lacking a tubercle on the dentary and having the posterior tip of the upper jaw not extending beyond a vertical through the anterior margin of the pupil, usually 10–11 anal fin soft rays, 33–35 midlateral scales, a narrow midlateral band (ca. half midlateral scale width at anal fin origin), and 3 distinct longitudinal broken black lines laterally and ventrolaterally on the body. A lectotype is designated for Atherina lineata Günther, 1872, regarded as a junior synonym of Atherinomorus endrachtensis. Atherinomorus duodecimalis, known from Sri Lanka, Thailand, Yaeyama Is. (Japan), the Philippines, Indonesia, New Guinea, Queensland (Australia), and New Caledonia, differs from other congeners in having a tubercle on the posterior end of the dentary, the posterior tip of the upper jaw not extending beyond a vertical through the anterior margin of the pupil, usually 12–13 anal fin soft rays, 35–38 midlateral scales, and a narrow midlateral band (ca. 1/2 or 3/4 midlateral scale width at anal fin origin). Atherina balabacensis Seale, 1910 is regarded as a junior synonym of Atherinomorus duodecimalis. Received: June 29, 2000 / Revised: October 31, 2000 / Accepted: January 16, 2001  相似文献   

2.
The Indo-Pacific marine atherinid fishes Atherinomorus forskalii (Rüppell, 1838), Atherinomorus lacunosus (Forster, 1801), and Atherinomorus pinguis (Lacepède, 1803) are redescribed as valid species based on the types and non-type specimens collected throughout the Indo-Pacific. They are similar to each other chiefly in having a wide midlateral band (almost the same or greater than the midlateral scale width), large mouth (posterior tip of upper jaw reaching to or beyond a vertical through anterior margin of pupil), and no distinct tubercle at the posterior end of the dentary. All three species are distinguishable from congeners by those characters. The three species have long been confused with each other or synonymized erroneously as a single species. Atherinomorus forskalii, known from the Red Sea and eastern Mediterranean, differs from Atherinomorus lacunosus and Atherinomorus pinguis in having conspicuous, large endopterygoid teeth, forming obvious tooth ridges. Atherinomorus lacunosus, widely distributed in almost the entire Indo-Pacific, from East Africa to Tonga, north to southern Japan, and south to northern Australia, differs from Atherinomorus pinguis in having a wider midlateral band (the lower margin reaching to almost the center of the fourth scale row at level of the anal fin origin vs. the lower margin reaching to the ventral end of the third scale row in Atherinomorus pinguis) and more numerous midlateral scales (40–44 vs. 38–41 in Atherinomorus pinguis). Atherina morrisi Jordan and Starks, 1906, Hepsetia pinguis mineri Nichols and Roemhild, 1951, Pranesus capricornensis Woodland, 1961, Pranesus maculatus Taylor, 1964, and Pranesus pinguis ruppelli Smith, 1965, are regarded as junior synonyms of Atherinomorus lacunosus. Atherinomorus pinguis is also widely distributed in the Indo-West Pacific, from East Africa to northern Australia and north to southern Japan. Atherina pectoralis Valenciennes, 1835, is considered a junior synonym of Atherinomorus pinguis. Supplementary material to this paper is available in electronic format at  相似文献   

3.
The Australian marine atherinid fish, Atherinomorus vaigiensis (Quoy and Gaimard, 1825), having long been synonymized under A. lacunosus (Forster in Bloch and Schneider, 1801), is redescribed as a valid species based on the holotype and non-type specimens. Atherinomorus vaigiensis, known only from eastern and western Australia, differs from other congeners in lacking a distinct tubercle on the posterior end of the dentary and having the posterior tip of the upper jaw not extending beyond a vertical through the anterior margin of the pupil, 12–15 anal fin soft rays, 24–28 lower gill rakers, 39–42 midlateral scales, and a narrow midlateral band (width about 2/3 to 5/6 that of midlateral scale at level of anal fin origin). Atherina cylindrica Valenciennes in Cuvier and Valenciennes, 1835 and Pranesus ogilbyi Whitely, 1930 are regarded as junior synonyms of Atherinomorus vaigiensis. Received: April 26, 2001 / Revised: July 11, 2001 / Accepted: July 16, 2001  相似文献   

4.
Two new atherinid fishes, Hypoatherina golanii and Hypoatherina lunata, are described based on specimens collected from the wide range of the Indo-West Pacific. The former species is known from the Red Sea and was confused with Hypoatherina barnesi because it has a somewhat wide midlateral band and overlapping meristic counts. Hypoatherina golanii is distinguished from its congeners by the midlateral scales with an indented posterior margin, posterior margin of anterior predorsal scales with a spatular outgrowth, posterior margin of axillary scales without a distinct projection, and posterior end of maxilla not slanted downward. Hypoatherina lunata is distributed in the waters of southern Japan (Okinawa and Kagoshima prefectures) and Indonesia (North Sulawesi, Maluku, and Papua), but was confused with Hypoatherina woodwardi. Hypoatherina lunata is distinguished from its congeners in having a distinct crescent marking in front of the eye and the anus usually situated anterior to the tip of the pelvic fin.  相似文献   

5.
A review of Tirant’s collections and examination of types has resulted in the reidentification ofHaplocheilus argyrotaenia Tirant asHypoatherina valenciennei (Bleeker) which is found throughout the southwestern Pacific and as far north as Japan. The taxonomic status ofH. valenciennei is clarified and Bleeker’s emendation of the original specific epithetvalenciennei tovalenciennesi is rejected. The systematic position of this species is difficult to determine sinceH. valenciennei shows affinities with bothHypoatherina andAtherinomorus. In the light of the present knowledge, Bleeker’s species appears to have greater affinities withHypoatherina and is therefore placed in this genus.  相似文献   

6.
Two new species of Leporinus are described from tributaries of the Rio Amazonas in Brazil. One species is known from the Jari and Tapajós River basins, and is identified on the basis of a gas bladder reduced in size, a dark midlateral stripe on the body, dark transverse bars on the dorsum, a subinferior mouth, three teeth on the premaxilla, four teeth on the dentary and 16 scale rows around the caudal peduncle. The second new species is known from the Tocantins, Xingu and Tapajós River basins, and is identified on the basis of three dark longitudinal stripes on the body, a subinferior mouth, three teeth on the premaxilla, four teeth on the dentary and 12 scale rows around the caudal peduncle. In addition, Leporinus striatus is redescribed based on type and additional specimens from the Río de La Plata, Amazonas, Orinoco, Atrato, Magdalena and Sinu River basins. Leporinus striatus is identified on the basis of four dark longitudinal stripes on the body, a subterminal mouth, three teeth on the premaxilla, four teeth on the dentary and 16 scale rows around the caudal peduncle.  相似文献   

7.
Turcichondrostoma, a new genus, from the Southwestern Anatolia is distinguished by having fewer gill rakers on first gill arch and morphologies of premaxilla and dentary bones. In addition, as a result of the phylogenetic analyses based on combine data set (mtDNA COI + Cytb) sequences (1706 bp.), Turcichondrostoma genus was recovered with high posterior probability value (BI PP:1.0) and strong-supported bootstrap value (ML BP: 100%) among the former Chondrostoma groups. Also, high K2P mean genetic distance values (more than 7.84%) differentiated genus Turcichondrostoma from the other genera of former Chondrostoma group. The results of both morphological-osteological and molecular analyses are congruent with each other. The results of this study revealed that the genus Turcichondrostoma is easily distinguished from the genera in Chondrostoma group.  相似文献   

8.
Atherinomorus aetholepis sp. nov. is described from the holotype and 51 paratypes, 44–72 mm in standard length, collected from Indonesian and Philippine waters. The species is similar to other congeners in general body appearance, especially A. duodecimalis and A. regina, in having a slender body, a tubercle on the posterior end of the dentary, and a narrow midlateral band, but clearly differing from them in having a long spatular outgrowth on the posterior margins of most of the predorsal and interdorsal scales. Additionally, the species differs from A. duodecimalis in having a more slender body [body depth 17–22 (mean 19) % SL vs. 19–25 (mean 22) % SL], more midlateral scales [37–40 (mean 38.4) vs. 35–38 (mean 36.6)], more total vertebrae [38–42 (mean 39.9) vs. 36–40 (mean 38.0)], and fewer lower gill rakers [18–22 (mean 20.2) vs. 20–25 (mean 22.3)], and from A. regina in having more anal fin soft rays (12–14 vs. 9–10). Electronic supplementary material to this article is available at and accessible to authorized users. Received: October 22, 2001 / Revised: March 14, 2002 / Accepted: March 26, 2002 An erratum to this article is available at .  相似文献   

9.
Clevosaurus was a cosmopolitan rhynchocephalian genus, known from the Late Triassic to the Early Jurassic. In South America this genus is represented by C. brasiliensis, an important component of the Linha São Luiz taphocoenosis, on the top of the Norian Santa Maria 2 Sequence of Southern Brazil. The best preserved and most abundant bone elements of C. brasiliensis are dentaries, in which variations of shape and size are observed. The aim of this study is to describe and evaluate the variation, using geometric morphometrics methods. Geometric morphometric analysis of 10 specimens highlights variations in relative size of the dentary. Most of the variation observed for PC1 (83.3%) is likely related to ontogeny, and PC2 (10.0%) is likely related to taphonomic signatures. The development patterns observed, such as the growth of the dentary, consists of differential growth in length between the posterior portion of the dentary, that grows at a higher rate, regarding the anterior portion of the element. This allometric growth is similar to what is observed in other rhynchocephalians and is accompanied by the allometric skull growth, similar to the trend exhibited by clevosaurs. The taphocoenosis is bimodal (juveniles and adults) with a bias towards adult preservation. Some diagenetic influence is reflected in deformed skulls and this is observed in the tangent-plot. Finally, a strong correlation was detected between the taphonomic signatures and the PC2, regarding specially disarticulation and degree of fragmentation.  相似文献   

10.
11.
Mosasaurus beaugei Arambourg, 1952 was based on isolated teeth from the Maastrichtian phosphatic deposits of Morocco. The recent discovery of new material, including skull and mandibular remains, improves our knowledge of this species. M. beaugei shares the following synapomorphies with the genus Mosasaurus: large teeth bearing two prominent carinae and with asymmetrical labial and lingual surfaces, the labial one being flattened and strongly facetted and the lingual one being convex; premaxillae with a small pointed rostrum and dentary without rostrum; palatal elements closely united; coronoid with very large ventromedial process overlying the prearticular. M. beaugei is characterised by the following autapomorphies: 12-13 maxillary teeth; marginal teeth bearing 3-5 prisms on the labial surface and 8-9 on the lingual one; palatine with posterior border concave and perpendicular to the long axis of the skull; splenial visible laterally on half of the dentary ventral surface; coronoid with anterior wing well developed and bearing two notches. M. beaugei is only known to date in the Maastrichtian phosphates of Morocco.  相似文献   

12.

Background

The earliest dinosaurs are from the early Late Triassic (Carnian) of South America. By the Carnian the main clades Saurischia and Ornithischia were already established, and the presence of the most primitive known sauropodomorph Saturnalia suggests also that Saurischia had already diverged into Theropoda and Sauropodomorpha. Knowledge of Carnian sauropodomorphs has been restricted to this single species.

Methodology/Principal Findings

We describe a new small sauropodomorph dinosaur from the Ischigualsto Formation (Carnian) in northwest Argentina, Panphagia protos gen. et sp. nov., on the basis of a partial skeleton. The genus and species are characterized by an anteroposteriorly elongated fossa on the base of the anteroventral process of the nasal; wide lateral flange on the quadrate with a large foramen; deep groove on the lateral surface of the lower jaw surrounded by prominent dorsal and ventral ridges; bifurcated posteroventral process of the dentary; long retroarticular process transversally wider than the articular area for the quadrate; oval scars on the lateral surface of the posterior border of the centra of cervical vertebrae; distinct prominences on the neural arc of the anterior cervical vertebra; distal end of the scapular blade nearly three times wider than the neck; scapular blade with an expanded posterodistal corner; and medial lamina of brevis fossa twice as wide as the iliac spine.

Conclusions/Significance

We regard Panphagia as the most basal sauropodomorph, which shares the following apomorphies with Saturnalia and more derived sauropodomorphs: basally constricted crowns; lanceolate crowns; teeth of the anterior quarter of the dentary higher than the others; and short posterolateral flange of distal tibia. The presence of Panphagia at the base of the early Carnian Ischigualasto Formation suggests an earlier origin of Sauropodomorpha during the Middle Triassic.  相似文献   

13.
A marine hypotrich ciliate, Heterotachysoma multinucleatum (Gong and Choi, 2007) n. comb., found in coastal waters near Qingdao, China, was investigated. Heterotachysoma multinucleatum is characterized by its dorsal ciliature arranged in Gonostomum-pattern. Additionally, a new genus, Heterotachysoma n. gen., is established which is mainly characterized by: 18-cirri pattern; flexible body; three dorsal kineties with no dorsomarginal kineties nor kinety fragmentation; one right and one left row of marginal cirri; caudal cirri absent. The genus Tachysoma is redefined, and three new combinations, T. multinucleatum, T. ovatum and T. dragescoi, are proposed. The morphogenesis of Hemigastrostyla enigmatica (Dragesco and Dragesco-Kernéis, 1986) Song and Wilbert, 1997, is also described. Compared with that of its congeners, the differences are mainly in the dorsal ciliature: (1) the dorsal kinety anlagen are formed de novo in H. enigmatica (vs. intrakinetally in H. paraenigmatica and H. elongata); (2) the dorsal kineties anlagen develop in secondary mode in H. enigmatica (vs. primary mode in H. paraenigmatica); (3) the kinetal fragment anterior to the right marginal row in both filial product is absent in both H. enigmatica and H. elongata (vs. present in H. paraenigmatica). These findings suggest that morphogenesis is not uniform among members of the genus Hemigastrostyla.  相似文献   

14.
《Annales de Paléontologie》2019,105(4):269-274
Two crocodilian anterior cranium parts from Takut Khon Village sand pit, Chaloem Phrakiat District, Nakhon Ratchasima Province, are presently described. Their morphology indicates that the specimens belong to a single species based on the presence of several similar characters such as a hole for the reception of the first dentary tooth at the anterior edge of the premaxillary bone; anterior tip of nasal elongate and projecting into the posterior margin of the external nares; wavy suture line between the posterior part of the nasal with the anterior margin of prefrontal and frontal processes. The cranium morphology is extremely close to Crocodylus siamensis Schneider, 1801 (Siamese crocodile) and conforming the existence of Csiamensis from the Middle Pleistocene in Thailand.  相似文献   

15.
A new basal hadrosauroid dinosaur from the Lower Cretaceous Khok Kruat Formation of Thailand, Sirindhorna khoratensis gen. et sp. nov is described. The new taxon is based on composite skull and mandible including premaxilla, maxilla, jugal, quadrate, braincases, predentary, dentaries, surangular, and maxillary and dentary teeth. It is diagnostic by such characters as, sagittal crest extending along entire dorsal surface of the parietal and reaching the frontoparietal suture (autapomorphy), transversely straight frontoparietal suture, caudodorsally faced supraoccipital, no participation of the supraoccipital in the foramen magnum, mesiodistally wide leaf-shaped dentary tooth with primary and secondary ridges on the lingual surface of the crown, perpendicularly-erected and large coronoid process of dentary, and nonvisible antorbital fossa of the maxilla in lateral view. Phylogenetic analysis revealed S. khoratensis as among the most basal hadrosauroids. Sirindhorna khoratensis is the best-preserved iguanodontian ornithopod in Southeast Asia and sheds new light to resolve the evolution of basal hadrosauriforms.  相似文献   

16.
A new styracosternan ornithopod genus and species is here described based on a partial postcranial skeleton and an associated dentary tooth of a single specimen from the Arcillas de Morella Formation (Early Cretaceous, late Barremian) at the Morella locality, (Castellón, Spain). Morelladon beltrani gen. et sp. nov. is diagnosed by eight autapomorphic features. The set of autapomorphies includes: very elongated and vertical neural spines of the dorsal vertebrae, midline keel on ventral surface of the second to fourth sacral vertebrae restricted to the anterior half of the centrum, a posterodorsally inclined medial ridge on the postacetabular process of the ilium that meets its dorsal margin and distal end of the straight ischial shaft laterally expanded, among others. Phylogenetic analyses reveal that the new Iberian form is more closely related to its synchronic and sympatric contemporary European taxa Iguanodon bernissartensis and Mantellisaurus atherfieldensis, known from Western Europe, than to other Early Cretaceous Iberian styracosternans (Delapparentia turolensis and Proa valdearinnoensis). The recognition of Morelladon beltrani gen. et sp. nov. indicates that the Iberian Peninsula was home to a highly diverse medium to large bodied styracosternan assemblage during the Early Cretaceous.  相似文献   

17.
A systematic revision of flying fishes of the subgenus Hirundichthys s.str was carried out based on a study of meristic and morphometric traits and characteristics of pigmentation of fishes from the local populations of species belonging to the subgenus. It is found out that the subgenus includes four species: oceanic H. speculiger from the Atlantic, Pacific and Indian Oceans, oceanic H. indicus sp.n. from the waters of the Indian Ocean, nerito-oceanic H. oxycephalus from the waters of the Indo-West Pacific and nerito-oceanic H. affinis from the Atlantic Ocean. The first part of the review focuses on two oceanic species with a large “mirror” on the pectoral fins: H. speculiger and H. indicus. A comparison of local populations showed that the species H. indicus is polytypic and consists of two subspecies. One of the subspecies—nominative H. indicus indicus—is distributed in the western and the central parts of the Indian Ocean and the other—H. indicus orientalis ssp.n.—in the Eastern Indian Ocean. Maps showing a geographical distribution of the species and the subspecies in the World Ocean are drawn up.  相似文献   

18.
A new species of Megaleporinus is described from the Rio de Contas, a coastal drainage of eastern Brazil, and its phylogenetic relationships are studied using molecular data. The new species is unique among Anostomidae by possessing two exclusive features: an irregular dark longitudinal stripe from supracleithrum to second midlateral blotch and anterior cranial fontanel partially closed. In addition, the new species is diagnosed by having three premaxillary teeth, three dentary teeth, 37 or 38 scales in lateral line, 16 scale rows around caudal peduncle, three dark midlateral blotches on body, and red fins in life. The new species is closely related to M. obtusidens from the São Francisco basin, corroborating previous studies that indicated that the latter represents a species complex as currently defined. The new species exhibits the first rib enlarged in mature males, a feature described for some congeners. The new species is herein considered to be Endangered under the IUCN criteria.  相似文献   

19.
The aim of the present study is to elucidate if Oxyporus philadelphi (Parmasto) Ryvarden and Botryodontia millavensis (Bourdot & Galzin) Duhem & H. Michel are conspecific, as suggested by their similar morphology. The analysis of ribosomal DNA ITS sequences indicate that the specimens of O. philadelphi and B. millavensis belong to a single species. The species is closely related to the type species (B. cirrata) of the genus Botryodontia, and therefore the name B. millavensis should currently be used for this taxon. Botryodontia millavensis grows on a wide selection of host species—Juniperus communis, Philadelphus coronarius, Picea abies, Fraxinus excelsior, Lonicera sp., J. turcomanica—and is distributed widely in temperate Eurasia.  相似文献   

20.
The genus Acyrtus Schultz, 1944 currently includes four species distributed in the western Atlantic (WA), three occurring from the Bahamas to the southern Caribbean, and one endemic to the Fernando de Noronha Archipelago in north-east Brazil. We describe a new species of Acyrtus based on morphology and genetics from several individuals caught at artificial hard substrates deployed between 10 and 16 m deep at Malpelo Island, Colombian Pacific. The Malpelo clingfish, Acyrtus arturo new species, differs from all its WA congeners by a combination of morphology, meristics and genetics. This species is unique within Acyrtus in having the greatest number of caudal rays (12–13). It can also be distinguished by the greater body height (19.8–27.8% standard length), its longer disc (34.0–39.1% standard length) and the greater distance between anus and disc (13.9–18.1% standard length). A. arturo sp. nov. is the first Acyrtus so far recorded from the eastern Pacific and adds to the already high number of fishes endemic to Colombia's remote oceanic territory of Malpelo.  相似文献   

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