Solving the mystery of crinoid ancestry: new fossil evidence of arm origin and development

2009 ◽  
Vol 83 (3) ◽  
pp. 350-364 ◽  
Author(s):  
Thomas E. Guensburg ◽  
James Sprinkle
Keyword(s):  
New Genus ◽  
First Record ◽  
New Genus And Species ◽  
Early Ordovician ◽  
New Family ◽  
Fossil Evidence

Apektocrinus ubaghsinew genus and species is a monospecific taxon assigned to the new family Apektocrinidae based on additional preparation of a single previously studied specimen.Apektocrinusis among the oldest known crinoids (Early Tremadoc, Early Ordovician). Although expressing crinoid apomorphies, it is interpreted as retaining plesiomorphies in its arms reflecting early edrioasteroid rather than blastozoan (eocrinoid) ancestry. Apomorphies represent basal crinoid and cladid (crownward) levels of phylogeny.Restudy fortifies previous reports of the presence of a basal echinoderm plesiomorphy; floor plates above brachials in the arms ofApektocrinus, as well as in other approximately contemporary crinoids.Apektocrinusfurnishes the first record of podial basins in crinoid arms. Arms and calyx ofApektocrinusmerge gradually, facilitated by continuations of interbrachials (extraxial body plates) extending onto the arms and separating floor plates from brachials. These arm interbrachials, which diminish and pinch out distally as floor plates nestle into the brachial (adoral) groove, have not been recognized as such in crinoids.

New Monoplacophora (Mollusca) from Late Cambrian and Early Ordovician of Missouri

1986 ◽  
Vol 60 (3) ◽  
pp. 606-626 ◽  
Author(s):  
Bruce L. Stinchcomb
Keyword(s):  
New Species ◽  
New Genus ◽  
New Genera ◽  
New Genus And Species ◽  
Upper Cambrian ◽  
Early Ordovician ◽  
New Family ◽  
Late Cambrian ◽  
Lower Ordovician ◽  
A New Species

Fourteen new species and six new genera of the molluscan class Monoplacophora are described from the Upper Cambrian Potosi and Eminence formations and the Lower Ordovician Gasconade Formation of the Ozark Uplift of Missouri and some new biostratigraphic horizons are introduced. A new superfamily, the Hypseloconellacea nom. trans. Knight, 1956, and a new family, the Shelbyoceridae, are named. The genus Proplina is represented by five new species: P. inflatus, P. suttoni from the Cambrian Potosi Formation, P. arcua from the Cambrian Eminence Formation and P. meramecensis and P. sibeliusi from the Lower Ordovician Gasconade Formation. A new genus and species in the subfamily Proplininae, Ozarkplina meramecensis, is described from the Upper Cambrian Eminence Formation. Four new monoplacophoran genera in the superfamily Hypseloconellacea and their species are described, including: Cambrioconus expansus, Orthoconus striatus, Cornuella parva from the Eminence Formation, and Gasconadeoconus ponderosa, G. waynesvillensis, G. expansus from the Gasconade Formation. A new genus in the new family Shelbyoceridae, Archeoconus missourensis, is described from the Eminence Formation and a new species of Shelbyoceras, S. bigpineyensis, is described from the Gasconade Formation.

Pseudoditrichum mirabile gen. et sp. nov. (Musci: Pseudoditrichaceae fam. nov.), a unique moss from Great Bear Lake, Northwest Territories

1974 ◽  
Vol 52 (4) ◽  
pp. 701-705 ◽  
Author(s):  
William Campbell Steere ◽  
Zennoske Iwatsuki
Keyword(s):  
Northwest Territories ◽  
New Genus ◽  
The Arctic ◽  
Phylogenetic Position ◽  
New Genus And Species ◽  
Arctic Circle ◽  
New Family ◽  
Bear Lake ◽  
Evolutionary Level

The name Pseudoditrichum mirabile Steere et Iwatsuki is proposed for a minute moss with leafy stem 1-3 mm high and seta 6 mm long; it was collected on calcareous silt near the Sloan River, Great Bear Lake, Northwest Territories, only a few miles south of the Arctic Circle. The gametophytic characters agree well with those of the Ditrichaceae, a relatively primitive family, but the peristome is clearly double, with the inner and outer teeth opposite, which thereby indicates a much more advanced phylogenetic position, perhaps at the evolutionary level of the Funariaceae. As the combination of gametophytic and sporophytic characteristics exhibited by this moss does not occur in any existing family of mosses, it is therefore deemed necessary to create the new family Pseudoditrichaceae for the new genus and species described here.

Xenosellidae, a new family of Janiroidea (Asellota: Isopoda:  Crustacea), for Xenosella coxospinosa gen. nov., sp. nov.,  from the marine bathyal of eastern Australia

Zootaxa ◽  
2005 ◽  
Vol 1085 (1) ◽  
pp. 21 ◽  
Author(s):  
JEAN JUST
Keyword(s):  
New Species ◽  
Body Shape ◽  
New Genus ◽  
New Genus And Species ◽  
South Eastern ◽  
Incertae Sedis ◽  
New Family ◽  
Eastern Australia ◽  
Similar Body ◽  
South Eastern Australia

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.

scholarly journals Olmiana argentina, a new genus and species of Achilidae (Hemiptera, Fulgoromorpha) from Argentina

Zootaxa ◽  
2010 ◽  
Vol 2661 (1) ◽  
pp. 47 ◽  
Author(s):  
A. GUGLIELMINO ◽  
C. BÜCKLE ◽  
A. F. EMELJANOV
Keyword(s):  
New Genus ◽  
Larval Instar ◽  
First Record ◽  
Systematic Position ◽  
New Genus And Species

The first record of the planthopper tribe Achilini from Argentina is established with the description of Olmiana argentina gen. and sp. nov.. Details of the fifth larval instar are described. The systematic position of the new genus within the Achilidae is discussed, and a key to the genera of the subtribe Achilina is provided.

A remarkable new genus and species of Hansenauropodidae (Myriapoda, Pauropoda) from the seashore of Hainan Island, China

Zootaxa ◽  
2020 ◽  
Vol 4803 (2) ◽  
pp. 373-380
Author(s):  
YUN BU
Keyword(s):  
South China ◽  
New Genus ◽  
Hainan Island ◽  
First Record ◽  
New Genus And Species ◽  
Littoral Habitat ◽  
The Family ◽  
Marine Littoral

Psammopauropus macrospinus gen. et sp. n., a remarkable new genus and species of the pauropod family Hansenauropodidae is described from the marine littoral habitat of Hainan Island, South China. It has one pair of dorsal spines on the pygidium differentiated from seta a1, large globular seta st on pygidium, and globular distal setae on the tarsi by which Psammopauropus can be easily distinguished from all other genera of the family. In addition, the adaptive characters of the littoral pauropods are preliminary discussed. This is the first record of the family Hansenauropodidae from China. 

A new genus and species of Australian pergid sawfly (Hymenoptera: Symphyta, Pergidae) causing damage on grass (Poaceae)

Zootaxa ◽  
2005 ◽  
Vol 955 (1) ◽  
pp. 1 ◽  
Author(s):  
STEFAN SCHMIDT ◽  
GRAHAM BROWN
Keyword(s):  
New Species ◽  
New Genus ◽  
First Record ◽  
Northern Territory ◽  
Severe Damage ◽  
New Genus And Species

Dalia graminis, new genus and species, is described from the Darwin area in the Northern Territory, Australia. The new species belongs to the subfamily Euryinae and is most closely related to the genera Clarissa and Diphamorphos. Dalia graminis sp. nov. is the first record of an Australian pergid sawfly feeding on grass (Poaceae) causing severe damage on economically important crops.

scholarly journals Pinnotherotonia rumphiusi gen. et sp. nov., a new furry bivalve-associated pontoniine shrimp (Crustacea: Decapoda: Palaemonidae) from Palau

Zootaxa ◽  
2010 ◽  
Vol 2636 (1) ◽  
pp. 37 ◽  
Author(s):  
IVAN MARIN ◽  
GUSTAV PAULAY
Keyword(s):  
New Genus ◽  
First Record ◽  
Soft Bottom ◽  
New Genus And Species

A new genus and species of a furry, bivalve–associated pontoniine shrimp is described from Palau. This is the second pontoniine shrimp known to be associated with bivalves burrowing into soft bottom, and the first record of a venus clam (Bivalvia, Veneridae) as host for caridean shrimps.

A new genus and species of fossil Eodromeinae from the Yixian Formation of Western Liaoning, China (Coleoptera: Adephaga: Trachypachidae)

Zootaxa ◽  
2011 ◽  
Vol 2736 (1) ◽  
pp. 63 ◽  
Author(s):  
TING JIA ◽  
HONGBING LIANG ◽  
HUALI CHANG ◽  
DONG REN
Keyword(s):  
New Genus ◽  
First Record ◽  
Yixian Formation ◽  
New Genus And Species ◽  
Apical Angle ◽  
Western Liaoning

A new genus and species of fossil trachypachid Fortiseode pervalimand Jia & Ren gen. et sp. nov., is described and illustrated. The new fossil with large and strong mandibles, short and robust legs, and pronotum widest near apical angle differs from other members of Eodromeinae. It is the first record of fossil trachypachid from the Mesozoic Yixian Formation of Huangbanjigou, Liaoning, China.

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