scholarly journals Erect bifoliate species of Microporella (Bryozoa, Cheilostomata), fossil and modern

2020 ◽  
Author(s):  
Emanuela Di Martino ◽  
Paul D. Taylor ◽  
Dennis P. Gordon
Keyword(s):  
Molecular Phylogeny ◽  
Growth Form ◽  
Colony Growth ◽  
Early Miocene ◽  
Nominal Species ◽  
Number Of Species ◽  
Recent Species ◽  
Cheilostome Bryozoans

Microporella Hincks, 1877 is one of the most diverse genera of cheilostome bryozoans, containing more than 150 named species. Distributed globally since the early Miocene, the majority of species of Microporella have sheet-like colonies encrusting hard and / or ephemeral substrates, while a limited number of species have erect bifoliate colonies starting from an encrusting base. Herein, the four nominal species of erect bifoliate Microporella (M. bifoliata, M. hastigera, M. hyadesi and M. ordo) are revised, and one new Pliocene (M. tanyae sp. nov.) and three new Recent species (M. ordoides sp. nov., M. lingulata sp. nov. and M. modesta sp. nov.) are formally described. Furthermore, the lectotype and paralectotypes were designated for M. bifoliata and M. hastigera. An additional Recent species, Microporella sp. 1, is also described and illustrated but left in open nomenclature owing to the absence of ovicells in the single available fragment. Although the molecular phylogeny of Microporella has yet to be resolved, the diversity of character states present among the erect bifoliate species described here suggests that this colony growth-form is not monophyletic but has evolved on multiple occasions.

Patterns of morphological diversity among and within arcid bivalve species pairs separated by the Isthmus of Panama

2001 ◽  
Vol 75 (3) ◽  
pp. 590-606 ◽  
Author(s):  
Peter B. Marko ◽  
Jeremy B. C. Jackson
Keyword(s):  
Morphological Variation ◽  
Fossil Record ◽  
Eastern Pacific ◽  
Nominal Species ◽  
Western Atlantic ◽  
Isthmus Of Panama ◽  
Species Pairs ◽  
Recent Species ◽  
Discriminant Analyses ◽  
Collection Sites

Geminate species are morphologically similar sister-species found on either side of the Isthmus of Panama. The existence of all geminates in the tropical Eastern Pacific ocean and the Caribbean Sea is most often explained by vicariance: closure of the Central American Seaway 3.1 to 3.5 Ma simultaneously isolated populations of species with amphi-American distributions. In this paper, we test the potential of morphological measurements for discriminating between Recent geminate species pairs from three genera (Arca, Arcopsis, and Barbatia) in the bivalve family Arcidae and examine the prospects for distinguishing nominal species in the fossil record. Fourteen morphological variables were used to characterize shell shape and multivariate methods were used to discriminate between five Recent species pairs. Collection sites were also used as a priori groups for discrimination to describe patterns of intraspecific morphological variation and to evaluate differences among samples from different geographic regions.On average, 84 percent of specimens within geminate pairs are classified correctly following five separate discriminant analyses with nominal species as the grouping variable. Although all but one arcid species pair are discriminated with high statistical significance, some collection sites within species are highly morphologically distinct. Overall, a large proportion of specimens from each collection locality (79 percent on average) can be classified correctly to site although no single site possessed a multivariate centroid that was significantly different from all other conspecific centroids. The distinctiveness of some collection sites, however, raises the possibility that some nominal species may harbor cryptic species, indicating the need for wider geographic surveys of both molecular and morphological variation within geminate species pairs.The eigenvalue coefficients derived from the Recent samples of one geminate pair (Arca mutabilis and A. imbricata) were used to assess the potential for identifying arcid species in the fossil record. Discriminant analyses of fossil Arca indicate that the forms that characterize Recent A. mutabilis and A. imbricata are present in the fossil record as far back as the Late Early Miocene, in the Cantaure Formation of Venezuela. Because a deep water connection between the Eastern Pacific and Western Atlantic existed until the Middle Miocene, the morphological differences associated with Recent A. mutabilis and A. imbricata likely existed well before the rising Isthmus affected ocean circulation patterns in tropical America. Therefore, despite great overall morphological similarity, these putative geminate species likely have a time of divergence that is at least four times older than final seaway closure. The geographic distribution of fossils also suggests that morphological forms associated with each Recent species had amphi-American distributions both before and after isthmus formation but are now geographically restricted to either side of the isthmus in the Recent fauna.

New and little-known bryozoans from Monte León Formation (early Miocene, Argentina) and their paleobiogeographic relationships

2015 ◽  
Vol 89 (6) ◽  
pp. 956-965 ◽  
Author(s):  
Leandro M. Pérez ◽  
Juan López-Gappa ◽  
Miguel Griffin
Keyword(s):  
New Species ◽  
New Zealand ◽  
Close Relationships ◽  
Early Miocene ◽  
South American ◽  
The South ◽  
New Material ◽  
Recent Species ◽  
Stratigraphic Range

AbstractThe bryozoan fauna from the South American Cenozoic is poorly known. The study of new material collected in the Monte León Formation (early Miocene), gave us the opportunity to describe four new species: Valdemunitella canui n. sp., Foveolaria praecursor n. sp., Neothoa reptans n. sp., and Calyptotheca santacruzana n. sp. Two of them (V. canui and C. santacruzana) were first recorded by F. Canu and interpreted as recent species from the Australian bryozoan fauna, but are herein described as new species. The stratigraphic range of Otionella parvula (Canu, 1904) is extended to the early Miocene. The present study emphasizes the close relationships between the South American Neogene bryozoan faunas and those of other Gondwanan sub-continents such as New Zealand and Australia.

scholarly journals Origin, adaptive radiation and diversification of the Hawaiian lobeliads (Asterales: Campanulaceae)

2008 ◽  
Vol 276 (1656) ◽  
pp. 407-416 ◽  
Author(s):  
Thomas J Givnish ◽  
Kendra C Millam ◽  
Austin R Mast ◽  
Thomas B Paterson ◽  
Terra J Theim ◽  
...  
Keyword(s):  
Molecular Phylogeny ◽  
Tropical Forests ◽  
Adaptive Radiation ◽  
Growth Form ◽  
Oceanic Island ◽  
Tube Length ◽  
Tropical Plants ◽  
Limited Dispersal ◽  
Adaptive Radiations ◽  
Morphological Differences

The endemic Hawaiian lobeliads are exceptionally species rich and exhibit striking diversity in habitat, growth form, pollination biology and seed dispersal, but their origins and pattern of diversification remain shrouded in mystery. Up to five independent colonizations have been proposed based on morphological differences among extant taxa. We present a molecular phylogeny showing that the Hawaiian lobeliads are the product of one immigration event; that they are the largest plant clade on any single oceanic island or archipelago; that their ancestor arrived roughly 13 Myr ago; and that this ancestor was most likely woody, wind-dispersed, bird-pollinated, and adapted to open habitats at mid-elevations. Invasion of closed tropical forests is associated with evolution of fleshy fruits. Limited dispersal of such fruits in wet-forest understoreys appears to have accelerated speciation and led to a series of parallel adaptive radiations in Cyanea , with most species restricted to single islands. Consistency of Cyanea diversity across all tall islands except Hawai i suggests that diversification of Cyanea saturates in less than 1.5 Myr. Lobeliad diversity appears to reflect a hierarchical adaptive radiation in habitat, then elevation and flower-tube length, and provides important insights into the pattern and tempo of diversification in a species-rich clade of tropical plants.

scholarly journals III.—The Miocene Insect-fauna of Œningen, Baden

1895 ◽  
Vol 2 (3) ◽  
pp. 116-122 ◽  
Author(s):  
Samuel H. Scudder
Keyword(s):  
Fossil Insects ◽  
Nominal Species ◽  
Insect Fauna ◽  
Number Of Species ◽  
Fossil Insect ◽  
The World ◽  
Comparative Zoology ◽  
Louis Agassiz

Thanks solely to the labours of the late Oswald Heer, the fossil insect-fauna of Œningen is better known than that of any other locality or horizon in the world. But it is by no means so well known as it should be; for although Heer, in his latest enumeration of the specimens seen by him (Urwelt der Schweiz, 2e Aufl. 1879, p. 383), repeats precisely the same figures he has already given in 1861 (Recherches sur le climat du pays tert., p. 197), indicating in an interval of eighteen years no addition to his material (over 5000 specimens), his repeated additions to the number of species from that locality show that he had not fully worked over what he had. Indeed, thirty years ago, I arranged for exhibition in the Museum of Comparative Zoology at Cambridge a collection of nearly one hundred and fifty named species secured by Prof. Louis Agassiz from Heer, of which more than forty still remain undescribed; there are also a considerable number of merely nominal species enumerated by Heer in his Urwelt der Schweiz and elsewhere, duly catalogued by me in my Index to Fossil Insects (Bull. U. S. Geol. Surv. No. 71), but as yet neither described nor figured. In addition to this it may be noted that in the enumeration referred to above Heer mentions 543 species of beetles, while less than 270 nominal species have yet been published from Œningen, and only seven species from the Swiss Miocene, included in the enumeration.

Callochiton monteleonensis n. sp., first record of Polyplacophora (Mollusca) from the Neogene of Argentina

2011 ◽  
Vol 85 (6) ◽  
pp. 1181-1187 ◽  
Author(s):  
Diego Urteaga ◽  
Miguel Griffin ◽  
Guido Pastorino
Keyword(s):  
New Species ◽  
New Zealand ◽  
Central Area ◽  
First Record ◽  
Early Miocene ◽  
Southwestern Atlantic ◽  
Santa Cruz ◽  
Recent Species ◽  
A New Species

A new species of chiton is described from early Miocene deposits of the Monte León Formation, in Santa Cruz Province, Argentina. Callochiton monteleonensis n. sp. clearly differs from known fossil and Recent species of the southwestern Atlantic because the central area of its intermediate valves has a stepped appearance, in which each step is marked by a longitudinal rib. It is similar to Callochiton kapitiensis Mestayer, 1926, a Recent species from New Zealand. Biogeographic implications are discussed. This is the first record of a polyplacophoran from Neogene deposits of Argentina.

scholarly journals INDEX TO THE MANTIDÆ OF NORTH AMERICA, NORTH OF MEXICO

1896 ◽  
Vol 28 (8) ◽  
pp. 207-215 ◽  
Author(s):  
Samuel H. Scudder
Keyword(s):  
North America ◽  
Nominal Species ◽  
The West ◽  
East Indian ◽  
Number Of Species ◽  
North America North

In 1889, Westwood, in the Synopsis of the then known Mantidæ, prefixed to his Revisio insectorum familiæ Mantidorum, credits to North America, north of Mexico, nine species belonging to five genera,— Gonatista, Oligonyx, Thesprotia, Mantis, and Stagmomantis. several species were overlooked by him, and in reality up to the present time twenty-three nominal species have been at different times credited to this region and referred to ten genera,—Ameles, Empusa, Phasmomantis, Stagmatoptera, and Theoclytes, besides the foregoing. Several of the species, however, have been erroneously credited to this country, such as Empusa gongylodes and Mantis gemmata, both of which are East Indian. Several of the names, moreover, are synonyms of others, so that the number of species these references represent is speedily reduced more than one-half. All of these but Mantis Wheeleri Thom., Phasmomantis sumichrasti Sauss., and Oligonyx Uhleri Stal, I have seen, and to them can add several more not before recognized in the region in question, six of them being apparently hitherto undescribed, together with one genus. The total number of species is fifteen or sixteen, and of genera, eleven, only three of the genera—Litaneutria, Stagmomantis, and Oligonyx—having more than one species; undoubtedly more forms will be found in the West and South.

scholarly journals Bryophytes from some Caatinga areas in the state of Bahia (Brazil)

1998 ◽  
Vol 14 (1) ◽  
pp. 69-75
Author(s):  
Cid José Passos Bastos ◽  
Belén Albertos ◽  
Silvana Brito Vilas Bôas
Keyword(s):  
Characteristic Feature ◽  
Growth Form ◽  
The State ◽  
Vegetation Types ◽  
Dry Period ◽  
Moss Species ◽  
Number Of Species ◽  
Bryum Argenteum ◽  
Caatinga Vegetation ◽  
Hygrophilous Species

The caatinga is a deciduous and xerophilous vegetation that covers large areas in Brazil. An irregular rainfall with a marked dry period is a characteristic feature. This paper represents the first contribution to the knowledge of the bryoflora from caatinga vegetation in the State of Bahia. The survey was carried out in several areas from Bahia in which eigthteen species of bryophytes were found (15 mosses and 3 liverworts). The bryoflora from caatinga is composed mainly of generalists and xerophilous taxa, but even some hygrophilous species can be found. A number of species including Hyophiladelphus agrarius, Hyophila involuta, Calymperes palisotii ssp. richardii, Bryum argenteum, Entodontopsis leucostega, Octoblepharum albidum, Frullania ericoides also occur in other vegetation types. However, there are a number of species restricted to this type of vegetation, such as Helicophyllum torquatum and Riccia vitalii, at least in Bahia. Most moss species were acrocarpous with erect and short (short-turf) growth-form, whereas the foliose hepaticae were of incubous, and thallose forms.

Adding the West-African riverine component: Revision of the Recent freshwater snails belonging to Pseudocleopatra Thiele, 1928 (Caenogastropoda, Cerithioidea, Paludomidae)

Zootaxa ◽  
2019 ◽  
Vol 4674 (3) ◽  
pp. 301-328
Author(s):  
MARCO T. NEIBER ◽  
SANDRA M. KAHL ◽  
BENEDIKT WIGGERING ◽  
MATTHIAS GLAUBRECHT
Keyword(s):  
Lake Tanganyika ◽  
Molecular Genetic ◽  
West African ◽  
Nominal Species ◽  
Ratio Analysis ◽  
The West ◽  
Generic Level ◽  
Marine Gastropods ◽  
Recent Species ◽  
Component Revision

While Africa’s lacustrine gastropod fauna, in particular of Lake Tanganyika, has received much attention, the continent’s riverine malacofauna has long been neglected. Pseudocleopatra is a relatively poorly known paludomid gastropod genus with species found throughout the lower reaches of the West African Volta and Congo rivers. In the course of ongoing systematic revisions of African paludomids, we present here a morphometric analysis and revision of the recent species assigned to the genus, i.e., P. togoensis, P. voltana, P. dartevellei and P. bennikei, to improve taxonomic acuity for this group. We use available museum material for geometric morphometrics, multivariate ratio analysis and comparisons of radular and opercular characters. Our results demonstrate that the four recent species of Pseudocleopatra are clearly distinguishable on the basis of ratios of shell measurements as well as radular and opercular characters. Pseudocleopatra has generic-level synapomorphies including: concentric opercula with relatively large paucispiral nuclei, and rachidian radular teeth with usually 13–20 cusps. On the basis of this characterisation, the nominal species Cleopatra broecki is transferred to Pseudocleopatra. Additionally, the nominal taxon P. bennikei is synonymized with P. broecki n. comb. The phylogenetic relationships of Pseudocleopatra are currently unknown, but the observed tendency of some fossil taxa assigned to Pseudocleopatra towards thalassoidism, i.e., the resemblance to marine gastropods, has led to the hypothesis that some of the thalassoid endemics in Lake Tanganyika may have originated from or be related to Pseudocleopatra. Should this hypothesis be correct, which is in need of testing by molecular genetic methods when suitable samples become available, Pseudocleopatra may play a crucial role in understanding of the evolution of thalassoidism in African Paludomidae. 

Growth form in Silurian heliolitid corals: the influence of genetics and environment

Paleobiology ◽  
1991 ◽  
Vol 17 (4) ◽  
pp. 369-387 ◽  
Author(s):  
Graham A. Young ◽  
Colin T. Scrutton
Keyword(s):  
Sedimentation Rate ◽  
Growth Form ◽  
Energy Levels ◽  
Close Correlation ◽  
Colony Growth ◽  
Similar Response ◽  
Substrate Type ◽  
Profile Data ◽  
Light Levels ◽  
Simple Equations

Colony growth form in some Silurian heliolitid corals is analyzed by the measurement of their shape in profile. Data are presented for seven species, Stelliporella parvistella, Heliolites interstinctus, H. megastoma, H. daintreei, H. spongodes, Propora tubulata, and Plasmopora scita from three localities in Gotland, Sweden, and three localities in England. Intraspecific growth-form variation is presented on triangle diagrams. These plots allow variation to be compared between species present at each locality and between localities for each species. Results indicate that the overall potential for growth-form variation is genetically controlled and that levels of response to environmental stimuli may differ markedly between species. Stelliporella parvistella is a very plastic species, the only one developing branching growth in addition to other growth forms. Heliolites interstinctus is much less variable, dominantly tabular, domal, and low bulbous in form, but demonstrates a similar response. Propora tubulata has a tightly constrained bulbous growth form that shows little variation between localities. The other species are represented by few specimens, most of which parallel H. interstinctus. The likely moderating influences of light levels, substrate type, sedimentation rate, energy levels, and other variables on growth-form variation and species range are considered. The main environmental factor including ecophenotypic response is concluded to be sedimentation rate. A close correlation between this factor and growth form in S. parvistella indicates that form in this species is a particularly sensitive indicator of sedimentation rate and substrate conditions. No simple equations can be made between specific environments and one particular growth form in these corals.

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