Extreme reduction of morphological characters: a type of brachidial development found in several Late Cretaceous and Recent brachiopod species—new relationships between taxa previously listed as incertae sedis

Zootaxa ◽  
2018 ◽  
Vol 4444 (1) ◽  
pp. 1 ◽  
Author(s):  
ERIC SIMON ◽  
BERNARD MOTTEQUIN

Size reduction and development of a simplified brachidial structure occurred several times during the long evolution of the Phylum Brachiopoda. Even Recent forms may be micromorphic and paedomorphic with reduced brachidia or none at all. A revision of the Maastrichtian (Late Cretaceous) Terebratella (Morrisia?) suessi Bosquet, 1859 has allowed us to erect a new genus, Jagtithyris gen. nov., because its singular brachidium development does not match any platidiid structure. Such a brachidium has also been observed in another European Late Cretaceous brachiopod, which indicates that this type was not a unique morphological curiosity. This species is the micromorphic Campanian-Maastrichtian Leptothyrellopsis polonicus Bitner & Pisera, 1979, which has brachidial structures in common with Jagtithyris suessi comb. nov., although a number of differences have been observed. The genera Leptothyrellopsis and Jagtithyris gen. nov., are included in a new family, Jagtithyrididae fam. nov. During an ongoing revision of extant brachiopod faunas we have been led to recognize a link between this family and representatives of the genus Simplicithyris Zezina, 1976. The taxonomic position of this peculiar group is also discussed. 

Zootaxa ◽  
2005 ◽  
Vol 1085 (1) ◽  
pp. 21 ◽  
Author(s):  
JEAN JUST

A new genus and species of janiroidean Asellota, Xenosella coxospinosa, is described from the mid-bathyal slope off the coast of south-eastern Australia. Following a comparison of the new species to several families of broadly similar body shape, with emphasis on monotypic Pleurocopidae, a new family, Xenosellidae, is proposed for the new species. In the course of comparing relevant taxa, the current placements of Prethura Kensley in the Santiidae and Salvatiella Müller in the Munnidae are rejected. The two genera are considered to be incertae sedis within the Asellota superfamily Janiroidea pending further studies.


2018 ◽  
Vol 5 (1) ◽  
Author(s):  
Alessandro Garassino ◽  
Giovanni Pasini

We investigate a new decapod macruran discovered in deposits identified at the top of Gara Sbaa slope, located in SE Morocco, along the “Hamada des Kem Kem”, close to the Algerian border. These fossiliferous levels are known in the literature as part of the Late Cretaceous Kem Kem beds. We report the new family Amazighopsidae, created to accommodate Amazighopsis cretacica n. gen., n. sp. Indeed, some morphological characters, such as a short rostrum with the serrate upper margin, cervical and antennal grooves not forming the characteristic W-shaped pattern, the telson without diaeresis, lateral margins of the telson with one movable median spine and two movable distal spines, and the uropodal exopod without diaeresis, are so peculiar and unique to justify the erection of the new family tentatively ascribed to the infraorder Astacidea.


2016 ◽  
pp. 1 ◽  
Author(s):  
Michael S. Engel

A new genus and species of basal cyclostome Braconidae is described and figured from a male preserved in mid-Cretaceous amber from northern Myanmar.  <strong><em>Rhetinorhyssalus morticinus</em></strong> Engel, new genus and species, is interesting for its combination of primitive features such as a minute apical costal cell and anal stubs in the forewing, while lacking 2Cu in the hind wing, a putatively derived trait.  As such, the genus may represent a lineage diverging from the braconid stem subsequent to many protorhyssalines, while remaining basal relative to generalized cyclostome groups such as Rhyssalinae.  In addition, the Late Cretaceous <em>Diospilus allani</em> Brues, in Campanian Canadian amber, is transferred to <strong><em>Diorhyssalus</em></strong> Engel, new genus, and its similarity to <em>Rhetinorhyssalus</em> is discussed.  This transfer results in the new combination, <em>Diorhyssalus allani</em> (Brues).  Both genera are tentatively considered as subfamily <em>incertae sedis</em>.


1998 ◽  
Vol 67 (4) ◽  
pp. 257-266 ◽  
Author(s):  
Cees H.J. Hof

The eryonid decapod Eryon yehoachi Remy & Avnimelech, 1955, from the Late Cretaceous of Israel, is redescribed as a fossil stomatopod species within the new genus Ursquilla. This redescription is based on the original type specimen and two additional records from Israel and Jordan. The material allows a detailed reconstruction of the telson, the sixth abdominal tergite, and part of the uropods. The distinct telson ornamentation of these stomatopods justifies the erection of a new family within the superfamily Squilloidea.


2019 ◽  
Vol 187 (4) ◽  
pp. 1259-1277 ◽  
Author(s):  
Robin Kundrata ◽  
Stephan M Blank ◽  
Alexander S Prosvirov ◽  
Eliska Sormova ◽  
Matthew L Gimmel ◽  
...  

Abstract Cydistinae are a rare monogeneric beetle lineage from Asia with a convoluted history of classification, historically placed in various groups within the series Elateriformia. However, their position has never been rigorously tested. To resolve this long-standing puzzle, we are the first to present sequences of two nuclear and two mitochondrial markers for four species of Cydistinae to determine their phylogenetic position. We included these sequences in two rounds of analyses: one including a broad Elateriformia dataset to test placement at the superfamily/family level, and a second, including a richer, targeted sampling of presumed close relatives. Our results strongly support Cydistinae as sister to Phengodidae in a clade with Rhagophthalmidae. Based on our molecular phylogenetic results and examination of morphological characters, we hereby transfer the formerly unplaced Cydistinae into Phengodidae and provide diagnoses for the newly circumscribed Phengodidae, Cydistinae and Cydistus. Since both Phengodidae and Rhagophthalmidae have bioluminescent larvae and strongly neotenic females, similar features can be hypothesized for Cydistinae. Additionally, Cydistus minor is transferred to the new genus Microcydistus.


2016 ◽  
Vol 25 (2) ◽  
pp. 204-215 ◽  
Author(s):  
E.M. Chaban ◽  
P.V. Kijashko

The morphology of the soft body of two unique cephalaspid species, Eоscaphander fragilis Habe, 1952 and Cylichna magna Lemche, 1941, having two gizzard plates in their gizzards has been studied. Taxonomic position of the both species is discussed. The morphology of E. fragilis is described and illustrated for the first time. The species belongs to the monotypic genus which was considered previously as a junior synonym of the genus Scaphander. Feeding of E. fragilis on sponges has been noted. A new monotypic genus, Pseudocylichna gen. nov., has been described for Cylichna magna. Morphological differences of the gizzard plates and gizzard walls of the genera mentioned before have been shown. Both genera have been placed in a new family Eoscaphandridae fam. nov. based on their pair gizzard plates and the division of the gizzard wall into four segments by tendons of the connective tissue.


2007 ◽  
Vol 44 (12) ◽  
pp. 1741-1752 ◽  
Author(s):  
Rodney M Feldmann ◽  
Rong-Yu Li ◽  
Carrie E Schweitzer

Discovery of a single specimen of brachyuran decapod from the Campanian Millwood Member in southern Manitoba, Canada, permits description of a new genus and species, Cretacocarcinus smithi. Comparison of sternal architecture and general carapace morphology with potentially related taxa documents that the new genus, along with Camarocarcinus Holland and Cvancara, form a new family, Camarocarcinidae, tentatively assigned to the Raninoidea. The Camarocarcinidae are interpreted to have originated in the upper Midcontinental Seaway in the Late Cretaceous, survived the K–T extinction event(s), and dispersed into southern North Dakota, USA; Greenland; and Denmark in the Paleocene.


1994 ◽  
Vol 68 (2) ◽  
pp. 339-351 ◽  
Author(s):  
Thomas W. Kammer ◽  
William I. Ausich

Species of the late Osagean and early Meramecian advanced cladid crinoid genera (suborder Poteriocrinina) Adinocrinus, Eratocrinus, Lekocrinus n. gen., Linocrinus, Sarocrinus, and Worthenocrinus n. gen. from Illinois, Indiana, Iowa, Kentucky, and Missouri are redescribed and redefined from study of type material and museum collections. These species are considered to have advanced-grade calyces because of the substantial size reduction of the infrabasals and basals relative to the radials. Nomenclatural and systematic changes include the following: 1) Eratocrinus coxanus (Worthen, 1882) is a senior synonym of Zeacrinus keokuk Worthen, 1882; 2) E. commaticus (Miller, 1891a) is a senior synonym of Z. blairi Miller and Gurley, 1895; 3) Lekocrinus n. gen. is described and Scaphiocrinus divaricatus Hall, 1860, and Z. planobrachiatus Meek and Worthen, 1860, are assigned to this new genus; 4) Linocrinus praemorsus (Miller and Gurley, 1890a) is a senior synonym of Poteriocrinus lautus Miller and Gurley, 1896; 5) Sarocrinus kirki n. sp. is described; 6) P. varsoviensis Worthen, 1882, is assigned to Sarocrinus and is a senior synonym of P. tentaculatus Worthen, 1883, P. granilineus Miller and Gurley, 1890a, Z. pocillum Miller, 1891b, S. nitidus Kirk, 1942, and S. plenus Kirk, 1942; 7) P. asperatus Worthen, 1882, is assigned to Sarocrinus; 8) Worthenocrinus n. gen. is described and W. paterus n. sp. is assigned to this new genus; 9) Poteriocrinus iowensis Worthen, 1882, is considered a nomen dubium and placed in incertae sedis.


Phytotaxa ◽  
2019 ◽  
Vol 397 (2) ◽  
pp. 199
Author(s):  
TAIMY CANTILLO ◽  
DAVI AUGUSTO CARNEIRO DE ALMEIDA ◽  
JOSIANE SANTANA MONTEIRO ◽  
LUÍS F.P. GUSMÃO

In this study, Pararhexoacrodictys gen. nov., with Pa. catolensis as the type species is described and compared with morphologically similar Acrodictys-like genera. The new genus is phenotypically similar to both Rhexoacrodictys and Pseudoacrodictys but separated by other morphological characters. Pa. minima sp. nov. and two combinations, Pa. balansae and Pa. magnicornuata, are introduced, and new records of Pseudoacrodictys and Shrungabeeja are also registered for South America and the Neotropics.


Parasitology ◽  
1936 ◽  
Vol 28 (3) ◽  
pp. 446-451 ◽  
Author(s):  
Harley J. van Cleave

Specimens collected by the Swedish Expedition to the White Nile in 1901 have been identified as Rhadinorhynchus niloticus Meyer, 1932. On the basis of this material, including the first recorded females, the species has been restudied. Points wherein the individuals are unlike the forms included in the family Rhadinorhynchidae are presented in detail. A new genus, Tenuisentis, is proposed with Rhadinorhynchus niloticus as type. This new genus becomes type of a new family, the Tenuisentidae, which is assigned to the order Eoacanthocephala.


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