Gigantic scaphopods (Mollusca) from the Permian Akasaka Limestone, central Japan

2021 ◽  
pp. 1-15
Author(s):  
Kaito Asato ◽  
Tomoki Kase
Keyword(s):  
Species Richness ◽  
New Genus ◽  
Shell Morphology ◽  
Diagnostic Character ◽  
Central Japan ◽  
Molluscan Fauna ◽  
Single Locality

Abstract Paleozoic scaphopods are among the most poorly known mollusks because of their featureless tubular shell morphology and fragmentary preservation. An apical orifice at the posterior end of a conch is a diagnostic character of Scaphopoda that distinguishes them from other groups of animals that produce similar calcareous tubes, but this structure is rarely preserved. A rich molluscan fauna from the Permian Akasaka Limestone in central Japan includes scaphopod shells, and past studies have reported four species, all of which were based on fragmentary specimens. This study recognizes six species in the Akasaka Limestone mainly on the basis of museum/institution collections, and a new genus (Minodentalium) and three species (Prodentalium onoi, M. hayasakai, and M. okumurai) are described, two known species (P. akasakensis and P. neornatum) are redescribed in more detail, and one species (Prodentalium sp.) is described under open nomenclature. The following eight known species are allocated to the new genus Minodentalium: Plagioglypta furcata Waterhouse, 1980; Pl. girtyi Knight, 1940; Pl. subannulata Easton, 1962; Dentalium ingens De Koninck, 1843; D. meekianum Geinitz, 1866; Pl. prosseri Morningstar, 1922; Dentalium priscum Münster in Goldfuss, 1842; and D. herculeum De Koninck, 1863. All the species, except for M. hayasakai, are gigantic, reaching 200 mm or more in length. The species richness is the greatest known from a single locality/formation worldwide. UUID: http://zoobank.org/35405b9d-3ba7-40bf-87c5-3f2b550b1a6d

A New Early Campanian Rudist Fauna from San Luis Potosi in Mexico and Its Taxonomic and Stratigraphic Significance

2010 ◽  
Vol 84 (5) ◽  
pp. 974-995 ◽  
Author(s):  
Jose Maria Pons ◽  
Enric Vicens ◽  
Yolanda Pichardo ◽  
Javier Aguilar ◽  
Angélica Oviedo ◽  
...  
Keyword(s):  
New Genus ◽  
Carbonate Platform ◽  
Layer Structure ◽  
Geological Mapping ◽  
Shell Morphology ◽  
Southern Mexico ◽  
San Luis ◽  
Mexican State ◽  
San Luis Potosi ◽  
San Luis Potosí

A rudist fauna composed of the radiolitids Potosites tristantorresi new genus, new species and Radiolites acutocostata (Adkins), the hippuritids Barrettia cf. ruseae Chubb, Torreites sanchezi (Douvillé), and Vaccinites vermunti Mac Gillavry, plagioptychids, and antillocaprinids is described from a rudist limestone succession in the central Mexican State of San Luis Potosí. The previously known species, one radiolitid from Texas and three hippuritids from the Caribbean Biogeographic Province, indicate the early Campanian. The new genus is a large radiolitid with a coiled and canaliculated left valve. New observations on R. acutocostata and V. vermunti shell morphology and variability are provided. Observations made on well preserved specimens of the latter species clarify the outer shell layer structure of the hippuritids right valve and has taxonomic implications. This is the first report of genus Torreites in Mexico and one of the northernmost records of genus Barrettia, already reported in southern Mexico from Chiapas State. This rudist limestone succession (informally ‘Temazcal limestones’ herein) is an easy-to-recognize cartographical unit; up to now it and Santonian and Turonian units have been mapped as the El Abra Formation in most available geological maps. Recognition of the successive carbonate platform intervals, between El Abra and Cardenas formations, improves the geological mapping and the understanding of the Mexican Gulf western margin evolution during the Late Cretaceous.

Azumamiris vernalis: a new genus and species of Mirini from central Japan (Heteroptera: Miridae: Mirinae)

Zootaxa ◽  
2010 ◽  
Vol 2601 (1) ◽  
pp. 45 ◽  
Author(s):  
TOMOHIDE YASUNAGA
Keyword(s):  
New Species ◽  
New Genus ◽  
Instar Nymph ◽  
Dwarf Bamboo ◽  
New Genus And Species ◽  
Central Japan ◽  
Old World ◽  
Pleioblastus Chino ◽  
A New Species

Azumamiris, a new genus of mirine plant bug, is established to accommodate a new species, A. vernalis, which has occasionally been found in central Honshu, Japan. This univoltine mirine was confirmed to be associated with a gramineous dwarf bamboo, Pleioblastus chino (Fr. et Sav.) Makino, and the adults appear only in early May. The final instar nymph is also diagnosed and described. The present new genus is assumed to be allied to Stenotus Jakovlev known from the Old World and to continental Chinese Elthemidea Zheng. A key to the genera under discussion is provided.

Paleocene diversification of bucciniform gastropods on Seymour Island, Antarctica

1996 ◽  
Vol 70 (6) ◽  
pp. 923-934 ◽  
Author(s):  
Anton E. Oleinik ◽  
William J. Zinsmeister
Keyword(s):  
New Species ◽  
Mass Extinction ◽  
Fossil Record ◽  
New Genus ◽  
Shell Morphology ◽  
Geographic Isolation ◽  
Extinction Event ◽  
Early Paleocene ◽  
Mass Extinction Event ◽  
Seymour Island

Following the mass extinction event at the end of the Cretaceous, the marine molluscan faunas of the high southern latitudes underwent a marked period of diversification during the early Paleocene. The appearance of four new species belonging to the new genus Seymourosphaera, tentatively placed in the subfamily Pseudolivinae, from the lower Paleocene strata of Seymour Island, Antarctic Peninsula, clearly illustrates the post-Cretaceous extinction diversification. The abrupt radiation of the buccinids during the early Paleocene, was also apparently related to geographic isolation of Antarctica during final breakup of Gondwana. Comparative analysis of shell morphology of Seymourosphaera, new genus reveals close morphologic similarities, not only with taxa within Pseudolivinae, but also with several genera and subgenera belonging to the families Buccinidae and Nassariidae. However, incompleteness of the fossil record and a “generalized” shell morphology make difficult establishment of unequivocal phylogenetic relationships for Seymourosphaera. A taxonomic review of most closely related, and possibly ancestral genus Austrosphaera Camacho, 1949, is provided. The following new species of genus Seymourosphaera new genus are described: Seymourosphaera bulloides new species, S. subglobosa new species, S. depressa new species, and S. elevata new species.

Kobayashiceras gifuense, a new actinocerid cephalopod from the Lower Devonian of Japan

1998 ◽  
Vol 72 (1) ◽  
pp. 36-38 ◽  
Author(s):  
Shuji Niko
Keyword(s):  
New Species ◽  
Lower Devonian ◽  
Shell Morphology ◽  
Central Japan ◽  
Early Devonian

A new actinocerid genus, Kobayashiceras, is defined on the basis of Kobayashiceras gifuense new species from the Lochkovian (Early Devonian) of the Fukuji Formation, central Japan. This genus shares with known actinocerids in the apical shell morphology, but is diagnosed by its orthocerid like stenosiphonate form in the adoral shell. Its taxonomic and paleobiogeographic implications are discussed.

The genus Acellomyia González, a new taxonomic arrangement of its species and descriptions of a new genus and two new species from southern South America (Diptera: Tabanidae: Diachlorini)

Zootaxa ◽  
2017 ◽  
Vol 4337 (4) ◽  
pp. 523
Author(s):  
CHRISTIAN R. GONZÁLEZ
Keyword(s):  
Species Richness ◽  
New Species ◽  
South America ◽  
New Genus ◽  
Morphological Diversity ◽  
Southern Chile ◽  
Key To Species ◽  
Southern South America ◽  
Two New Species ◽  
Morphological Differences

The tabanid tribe Diachlorini (Diptera) is the most genus-rich tribe in the Tabanidae; the tribe is cosmopolitan, but the greatest species richness and morphological diversity are found in the Australasian and Neotropical Regions. A new arrangement for the species of Acellomyia González is given; Acellomyia lauta (Hine) is transferred to a new genus, Montismyia gen.n., based on its morphological differences from Acellomyia and geographical distribution. The morphological differences between Acellomyia and Montismyia gen. n. are discussed. Two new species, Acellomyia casablanca sp.n. and Acellomyia puyehue sp.n., are described from specimens collected in southern Chile. Comparison of the morphology of Acellomyia paulseni mapuche (Coscarón & Philip) stat.nov. indicate that they should be elevated to species rank. A key to species of Acellomyia is provided and diagnostic characters are illustrated. 

New Early Paleocene Mollusca from the Wangaloa Formation of South Island, New Zealand

1993 ◽  
Vol 67 (3) ◽  
pp. 360-369 ◽  
Author(s):  
Jeffrey D. Stilwell
Keyword(s):  
New Zealand ◽  
Southern Hemisphere ◽  
New Genus ◽  
New Records ◽  
Genetic Isolation ◽  
Shallow Marine ◽  
Early Paleocene ◽  
Molluscan Fauna ◽  
Three New Species ◽  
Early Paleogene

New Mollusca from the shallow marine, highly fossiliferous Wangaloa Formation of southeastern Otago, South Island, New Zealand, are described. This paper reports three new species and one new genus: Leionucula palaioanaxea n. sp. of the Nuculidae, Pyropsis zinsmeisteri n. sp. of the Tudiclidae, and Wangacteon grebneffi n. gen. and sp. of the Acteonidae. These taxa represent new records in New Zealand of apparently endemic taxa. The molluscan fauna of the Wangaloa Formation is important in the understanding of Paleogene biogeography of the Southern Hemisphere and changes in faunal composition of the Cretaceous–Tertiary Gondwana Realm. Genus- and species-level endemism in the “Wangaloan” fauna is marked and is probably a reflection of “greater New Zealand” 's geographic and genetic isolation during the Paleocene. Although deposits containing early Paleogene Mollusca are generally rare in the Southern Hemisphere, comparisons of known Gondwana molluscan taxa and those of similar age in the Northern Hemisphere indicate that the Mollusca of the Wangaloa Formation have Early Paleocene affinities. Microfossil evidence, in addition, supports an Early Paleocene age for the fauna. However, an uppermost Cretaceous age is indicated for the basal part of the Wangaloa Formation stratigraphically below the shell beds, but the K–T boundary has yet to be located.

Description of Amorbimorpha Kruse, new genus, from Mexico and the southern United States (Lepidoptera: Tortricidae: Sparganothini)

Zootaxa ◽  
2012 ◽  
Vol 3177 (1) ◽  
pp. 33 ◽  
Author(s):  
JAMES J. KRUSE
Keyword(s):  
United States ◽  
Species Richness ◽  
Type Species ◽  
New Genus ◽  
Southern United States ◽  
Central Mexico ◽  
New Combinations ◽  
Additional Species ◽  
Male And Female ◽  
Life History Data

Amorbimorpha Kruse, new genus, is described and illustrated. The genus ranges from Texas, U.S.A., south through Ve-racruz, Mexico, with greatest species richness documented from the middle to upper elevations of central Mexico. Twospecies are described as new: A. powelliana (type species) and A. mackayiana; the latter is the only species in the genusknown from the U.S.A. Also, two new combinations are proposed: A. schausiana (Walsingham, 1913) and A. spadicea(Walsingham, 1913). Male and female genitalia are illustrated for each species where known; A. spadicea is representedby a unique female. Limited biological and life history data are summarized based mainly on laboratory rearings from eggs deposited by confined females of A. powelliana. At least ten additional species remain to be described.

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