Systematics of organic-walled microfossils from the ca. 780–740 Ma Chuar Group, Grand Canyon, Arizona

2016 ◽  
Vol 90 (5) ◽  
pp. 815-853 ◽  
Author(s):  
Susannah M. Porter ◽  
Leigh Anne Riedman

AbstractThe ca. 780–740 Ma Chuar Group, Grand Canyon, Arizona, provides an exceptional record of life during the diversification of crown-group eukaryotes, just prior to the first Cryogenian glaciation. We document in detail the assemblage of organic-walled microfossils preserved in fine-grained siliciclastics throughout the unit. In contrast with earlier studies, we primarily used SEM to document fossil morphologies, augmented by transmitted light microscopy, FIB-SEM, and TEM. This resulted in the discovery of new species and the recognition of broad-ranging, intraspecific biological and taphonomic variation in other species. Twenty-two species and five unnamed morphotypes are described, including three new species:Kaibabia gemmulella,Microlepidopalla mira, andVolleyballia dehlerae; two new combinations:Galerosphaera walcottiiandLanulatisphaera laufeldii; and 17 previously described forms. The possible colonial green algaPalaeastrum dyptocranumButterfield in Butterfield, Knoll, and Swett, 1994 and the index fossilCerebrosphaera globosa(Ogurtsova and Sergeev, 1989) Sergeev and Schopf, 2010 (=C. buickiiButterfield, 1994) are described for the first time from Chuar rocks.Lanulatisphaera laufeldii, a locally abundant and globally widespread species characterized by submicrometer filamentous processes that form a reticulate network, may be a useful marker for the time interval just before the appearance of vase-shaped microfossils (VSMs) ca. 740 Ma.Organic-walled microfossil assemblages decline in diversity upsection, coincident with the appearance of VSMs and intermittent euxinia within the basin. Whether this pattern is due to preservational bias related to greater water depth or the higher TOC of upper Chuar rocks or instead reflects biotic turnover related to the spread of euxinic water masses in the basin is unknown.

2011 ◽  
Vol 182 (3) ◽  
pp. 231-240 ◽  
Author(s):  
Jérémy Anquetin

AbstractIn recent years, no less than five new species of early turtles have been described worldwide. Among them are three new turtles from Middle Jurassic deposits that partially fill a previous temporal and morphological gap in our knowledge of the early evolution of these shelled amniotes: Heckerochelys romani, Condorchelys antiqua and Eileanchelys waldmani. For the first time, the phylogenetic position of these three new species is tested in the context of the two presently competing cladistic models of turtle evolution. The addition of these taxa to each matrix does not favour or alter any of the two opposed hypotheses. However, it is demonstrated here that, by documenting yet unknown stages in the evolution of several morphological structures, these three species give stronger support to the model of an extended phylogenetic stem for turtles. These new lines of evidence include the structure of the vomer, the position of the aditus canalis stapedio-temporalis and of the posterior opening of the canalis cavernosus, and the morphology of the processus interfenestralis of the opisthotic.Recent discoveries also reinvigorate the debate about the palaeoecology of early turtles. Whereas simple morphological characters (e.g., shell fontanelle, ligamentous bridge, flattened carapace) can be misleading, forelimb proportions and shell bone histology have led to the conclusion that most stem turtles (i.e., Proganochelys quenstedti, Palaeochersis talampayensis, Proterochersis robusta, Kayentachelys aprix and meiolaniids) were terrestrial forms. At least two out of the five recently described early turtles have been convincingly interpreted as having aquatic habits: Odontochelys semitestacea and Eileanchelys waldmani. More investigation is needed, but this will undoubtedly trigger further debate on the primitive ecology of turtles and on the origin of aquatic habits in testudines (i.e., the crown-group), respectively.


2012 ◽  
Vol 44 (3) ◽  
pp. 339-362 ◽  
Author(s):  
Bharati O. SHARMA ◽  
Pradnya KHADILKAR ◽  
Urmila MAKHIJA

AbstractIn continuation of our ongoing revisionary studies on the lichen family Graphidaceae from India, a treatment of 25 species of the lichen genera Fissurina and Hemithecium from India is presented. In our earlier work on the lichen genus Fissurina, 16 species were reported from India. In the present study, 17 additional species of Fissurina from India are recognized. Nine species, viz. Fissurina andamanensis, F. disposita, F. immersa, F. indica, F. microcarpa, F. nicobarensis, F. simplex, F. sporolata, and F. submonospora, are described as new to science. Seven species, viz. Fissurina canlaonensis, F. cingalina, F. comparimuralis, F. monospora, F. nitidescens, F. rubiginosa, and F. subnitidula, are recorded for the first time from India. One species, Fissurina sp. 1, is recorded but not formally described as new due to scanty material. Eight species in the lichen genus Hemithecium, including three new species, viz. H. kodayarense, H. longilirellatum, H. verrucosum, and five new combinations, viz. Hemithecium andamanicum, H. flabillatum, H. flavoalbum, H. flexile, and H. norlabiatum, are also recognized in the present work. A revised key for the identification of all 33 species of Fissurina and 26 species of Hemithecium so far known from India is provided.


2020 ◽  
pp. 1-23
Author(s):  
Antonietta Rosso ◽  
Emanuela Di Martino ◽  
Andrew N. Ostrovsky

Abstract Cribrilinid bryozoans originating from Pleistocene deep-water sediments from two localities near Messina (Sicily, Italy)—Capo Milazzo (Gelasian) and Scoppo (Calabrian)—were examined. Five cribrilinid species were found, three in each locality and time interval, with only one species shared. Three species, Cribrilaria profunda n. sp., Glabrilaria transversocarinata n. sp., and Figularia spectabilis n. sp., are new to science. Of the two remaining species, Figularia figularis was already known from local fossil associations, whereas Glabrilaria pedunculata, a present-day Mediterranean species, is recorded for the first time as a fossil. New combinations are suggested for two species previously assigned to Puellina, Cribrilaria saldanhai (Harmelin, 2001) n. comb. and Cribrilaria mikelae (Harmelin, 2006) n. comb. The diagnosis of the genus Figularia was amended to include an erect growth morphology in addition to the encrusting form, and the occurrence of ooecia formed by the distal kenozooid. Following a literature revision of all species currently assigned to Figularia, the new combinations Vitrimurella capitifera (Canu and Bassler, 1929) n. comb. and Hayamiellina quaylei (Powell, 1967a) n. comb. are suggested, and problematic species are listed and briefly discussed. UUID: http://zoobank.org/b7b36152-bf7b-4e00-b6ec-2614b2a58f1b


Kew Bulletin ◽  
2020 ◽  
Vol 75 (4) ◽  
Author(s):  
Johan Hermans ◽  
Simon Verlynde ◽  
Landy Rajaovelona ◽  
Phillip J. Cribb ◽  
Jean-Michel Hervouet

SummaryThree new species: Angraecum archangelicum, A. polyphemus and A. rotundifolium are described for the first time. Pectinariella is evaluated; a case is made to keep it at subgeneric level and the necessary two new combinations are made. Angraecum dasycarpum is neotypified. Finally A. ochraceum and A. setipes are compared with the latter being reduced to a synonym of the former.


2017 ◽  
Author(s):  
Jérémy Anquetin

In recent years, no less than five new species of stem-group turtles have been described worldwide. Among them are three new turtles from Middle Jurassic deposits that partially fill a previous temporal and morphological gap in our knowledge of the early evolution of these shelled amniotes: Heckerochelys romani, Condorchelys antiqua and Eileanchelys waldmani. For the first time, the phylogenetic position of these three new species is tested in the context of the two presently competing cladistic models of turtle evolution. The addition of these taxa to each matrix does not favour or alter any of the two opposed hypotheses. However, it is demonstrated here that, by documenting yet unknown stages in the evolution of several morphological structures, these three species give stronger support to the model of an extended phylogenetic stem for turtles. These new lines of evidence include the structure of the vomer, the position of the aditus canalis stapedio-temporalis and of the posterior opening of the canalis cavernosus, and the morphology of the processus interfenestralis of the opisthotic. These characters should be considered for future phylogenetic analyses of turtle interrelationships.Recent discoveries also reinvigorate the debate about the palaeoecology of early turtles. Whereas simple morphological characters (e.g., shell fontanelle, ligamentous bridge, flattened carapace) can be misleading, forelimb proportions and shell bone histology have led to the conclusion that most stem turtles (i.e., Proganochelys quenstedti, Palaeochersis talampayensis, Proterochersis robusta, Kayentachelys aprix and meiolaniids) were terrestrial forms. On the contrary, it is generally accepted that crown-group turtles are ancestrally aquatic. Among the five recently described stem-group turtles, Odontochelys semitestacea and Eileanchelys waldmani have been convincingly interpreted as having aquatic habits, which suggests that basal turtles were ecologically diverse. More investigation is needed, but this will undoubtedly trigger further debate on the primitive ecology of turtles and on the origin of aquatic habits in Testudines (i.e., the crown-group), respectively.


ZooKeys ◽  
2020 ◽  
Vol 987 ◽  
pp. 135-156
Author(s):  
Shota Inoue ◽  
Shûhei Nomura ◽  
Zi-Wei Yin

The genus Pseudophanias Raffray, 1890 is discovered in Japan and Taiwan Island for the first time, with three new species: P. yaimensis Inoue, Nomura & Yin, sp. nov., P. nakanoi Inoue, Nomura & Yin, sp. nov., and P. excavatus Inoue, Nomura & Yin, sp. nov. It is the fifth tmesiphorine genus known from Japan and the first from Taiwan. The genus Chandleriella Hlaváč, 2000 is placed as a junior synonym of Pseudophanias, resulting in the following new combinations: P. termitophilus (Bryant, 1915), comb. nov., and P. yunnanicus (Yin, 2019), comb. nov. A list of world species, and a key to East and South Asian representatives of Pseudophanias is provided.


2018 ◽  
Vol 154 (1) ◽  
pp. 9-15
Author(s):  
Guillaume De Rougemont

The genus Tolmerinus Bernhauer is recorded from Borneo for the first time with the descriptions of three new species: T. brunneus sp.n., T. sharpi sp.n.and T. tutus sp.n.


2019 ◽  
Vol 27 (1) ◽  
pp. 38-64
Author(s):  
Thomas B. Croat ◽  
Xavier Delannay ◽  
Orlando O. Ortiz ◽  
Pedro Diaz Jiménez

A review of the aroid tribe Caladieae is presented, and three new species of Caladium Vent. and seven new species of Syngonium Schott are described and illustrated. Two species, C. picturatum K. Koch & C. D. Bouché and C. steudnerifolium Engl., previously considered to be synonymous with C. bicolor (Aiton) Vent., are fully redescribed. New species of Caladium are C. cortesae Croat & E. G. Gonç., C. palaciosii Croat & L. P. Hannon, and C. stevensonii Croat & Delannay. New species of Syngonium are S. adsettiorum Croat, O. Ortiz & J. S. Harrison, S. bastimentoense O. Ortiz & Croat, S. brewsterense Croat & Delannay, S. churchillii Croat & O. Ortiz, S. litense Croat, S. purpureospathum Croat & Raz, and S. tacotalpense Díaz-Jiménez & Croat. Syngonium yurimaguense Engl. is also reported for the first time outside the Amazon Basin.


Zootaxa ◽  
2012 ◽  
Vol 3280 (1) ◽  
pp. 1 ◽  
Author(s):  
AMAZONAS CHAGAS-JÚNIOR

Three new species of Otostigmus Porat, 1876 from Brazilian Atlantic Forest are described. Otostigmus beckeri sp. n. andO. lanceolatus sp. n. are described from the state of Bahia and O. giupponii sp. n. from the state of Espírito Santo. InBrazil, the otostigmine scolopendrid genus Otostigmus comprises 22 species. A summary of Brazilian Otostigmus speciesis presented with new distribution records, taxonomic remarks when appropriate and an identification key. Otostigmus sul-catus Meinert, 1886 is recorded for the first time from Brazil; the Andean Otostigmus silvestrii Kraepelin 1903, previouslyrecorded from Brazil, is here considered not to be present in this country. Eight nominal species are regarded here as newsynonyms. Five of them—Otostigmus pradoi Bücherl, 1939, O. longistigma Bücherl, 1939, O. longipes Bücherl, 1939,O. langei Bücherl, 1946 and O. dentifusus Bücherl, 1946—are based on females of O. tibialis Brölemann, 1902. O. latipesBücherl, 1954 is conspecific with and is considered a junior synonym of O. sulcatus Meinert, 1886; O. limbatus diminutusBücherl, 1946 is a junior synonym of O. limbatus Meinert, 1886 and O. fossulatus Attems, 1928 is a junior synonym of O. goeldii Brölemann, 1898. A lectotype is designated for O. goeldii.


Zootaxa ◽  
2019 ◽  
Vol 4624 (2) ◽  
pp. 256-266
Author(s):  
ANTONIO D. BRESCOVIT ◽  
LUIZ FERNANDO M. OLIVEIRA

Three new species of the genus Thaloe are described from Antillean region: Thaloe maricao n. sp., from Maricao, Puerto Rico and Virgin Island, Thaloe leboulet n. sp., from Le Boulet and Mariani, Haiti and Thaloe ebano n. sp., from the Dominican Republic. Females of species of this genus are described for the first time. 


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