Resolution of life habits using multiple morphologic criteria: Shell form and life-mode in turritelliform gastropods

Paleobiology ◽  
1982 ◽  
Vol 8 (4) ◽  
pp. 378-388 ◽  
Author(s):  
Philip W. Signor
Keyword(s):  
Marine Species ◽  
Morphological Characters ◽  
Mode I ◽  
Fossil Species ◽  
Behavioral Complexity ◽  
Shell Form ◽  
Life Mode ◽  
Life Habits ◽  
Valid Generalization

Shell form is not strictly linked to life habits in modern marine turritelliform gastropods. To test the usefulness of various morphological characters in determining life-mode, I present a set of predictions giving the expected distribution of characters occurring in turritelliform snails with three different life-modes. Burrowing species should lack sculpture, possess columellar folds and a flat whorl profile, and have an orthocline or prosocline aperture. Mobile epifaunal forms should have sculpture, a rounded whorl profile, a displaced tangential aperture and a smooth columella. Sedentary forms should resemble epifaunal forms but have non-tangential apertures. These predictions were tested with a sample of 105 Recent marine species. Each hypothesis was found to be a statistically valid generalization and in 92 of the species (88%) the life habits were correctly predicted. Accuracy may be further improved by considering additional features such as ratchet sculpture and disjunct or open coiling. These patterns of shell form can be used to interpret fossil species as burrowers, or as sedentary or active epifaunal forms. For example, the unusual Devonian murchisoniid gastropod Ptychocaulus verneuili is interpreted as an active burrower.The relatively imperfect relationship between shell form and life-mode in turritelliform gastropods, as compared to the Bivalvia, apparently results in part from the behavioral complexity of the Gastropoda. Gastropods have a repertoire of activities which would place them in different life-modes at different times; snail morphology reflects this complexity.

On Candinia (Sacoglossa: Juliidae), a new fossil genus of bivalved gastropods

1996 ◽  
Vol 70 (2) ◽  
pp. 230-235 ◽  
Author(s):  
Jacques Le Renard ◽  
Bruno Sabelli ◽  
Marco Taviani
Keyword(s):  
New Genus ◽  
First Record ◽  
Fossil Species ◽  
Shallow Marine ◽  
Marine Deposits ◽  
The Family ◽  
Life Habits ◽  
The Mediterranean ◽  
Fossil Genus ◽  
The Mediterranean Basin

The record of the fossil representatives of the family Juliidae is updated. The new genus Candinia is proposed, in the subfamily Juliinae, for two fossil species somewhat intermediate between Julia and Berthelinia. The new species Candinia pliocaenica is recorded from the lower Pliocene shallow marine deposits near Siena (Tuscany, Italy). This is the first record of Sacoglossa in the Mediterranean Basin. Based on the very specialized life habits of the Juliidae, it is suggested that subtropical Caulerpa algal prairies inhabited the Mediterranean during the early Pliocene, likely becoming extinct in this basin because of the mid-Pliocene climatic deterioration.

Reappraisal of the burrowing lobster Axius (Malacostraca: Decapoda: Axiidea) in the fossil record with notes on palaeobiogeography and description of a new species

2017 ◽  
Vol 188 (3) ◽  
pp. 12 ◽  
Author(s):  
Matúš Hyžný ◽  
Sten Lennart Jakobsen ◽  
René H. B. Fraaije
Keyword(s):  
Fossil Record ◽  
Type Species ◽  
Morphological Characters ◽  
Late Oligocene ◽  
The West ◽  
Fossil Species ◽  
Western Tethys ◽  
Preservation Potential ◽  
A New Species ◽  
Subjective Synonym

The fossil record of the burrowing lobster Axius is reviewed. A diagnosis based on the characters with preservation potential is supplied. Plioaxius lineadactylus Fraaije et al., 2011, from the Pliocene of Belgium and the Netherlands is considered congeneric with the type species of Axius. As a consequence, Plioaxius is considered a junior subjective synonym of Axius. A newly described species, Axius hofstedtae from the late Oligocene of Denmark is considered the oldest unequivocal representative of Axius. Both fossil species, A. hofstedtae n. sp. and A. lineadactylus n. comb., share numerous morphological characters with extant Axius stirhynchus. Scarcity of the Cenozoic Axiidae is ascribed to lack of study of the fossil record of this group rather than to low fossilization potential of its representatives. A preliminary scenario of the migration of Axius based on the scarce fossil record suggests the origin in the Western Tethys and subsequent dispersal westward into the West Atlantic and eastward into the West Pacific.

Phylogenetic overview of flat wasps (Hymenoptera, Bethylidae) reveals Elektroepyrinae, a new fossil subfamily

2020 ◽  
Vol 3 (3) ◽  
pp. 269-283
Author(s):  
WESLEY D. COLOMBO ◽  
EVGENY E. PERKOVSKY ◽  
CELSO O. AZEVEDO
Keyword(s):  
Lower Cretaceous ◽  
Phylogenetic Analyses ◽  
Morphological Characters ◽  
New Taxon ◽  
Fossil Species ◽  
Geological Record ◽  
Diverse Families ◽  
The Third ◽  
Extant Species ◽  
The Family

The flat wasps, Bethylidae, are cosmopolitan and one of the most diverse families of Chrysidoidea. Bethylidae have 2,920 described extant species and almost 90 fossil species. The oldest geological record of the family is the Lower Cretaceous, from Lebanese and Spanish ambers and Transbaikalian rock fossils. Here we describe and illustrate one new fossil subfamily of Bethylidae: †Elektroepyrinae subfam. nov. represented by †Elektroepyris Perrichot & Nel from the lowermost Eocene Oise amber (France), which was cladistically assessed against all other eight subfamilies of Bethylidae. The new taxon is easily distinguished from other subfamilies by the forewing venation with the third abscissa of Cu present. Phylogenetic analyses support the monophyly of all subfamilies of Bethylidae, with a matrix with 69 morphological characters and 22 terminal taxa from where †Elektroepyrinae subfam. nov. emerged as independent lineage from all other subfamilies.

Protanthomyza ryszardi sp. nov., another Eocene species of †Protanthomyzinae (Diptera: Anthomyzidae) from Baltic amber

2020 ◽  
Vol 3 (5) ◽  
pp. 473-482
Author(s):  
JINDŘICH ROHÁČEK ◽  
CHRISTEL HOFFEINS
Keyword(s):  
New Species ◽  
Morphological Characters ◽  
Baltic Amber ◽  
Fossil Species ◽  
Fore Femur ◽  
Extinct Genus

A new fossil species of Anthomyzidae (Diptera), viz. Protanthomyza ryszardi sp. nov. is described from Baltic amber (Eocene, 48–34 Ma) on the basis of one male and one female inclusion found in the same amber specimen. This is the tenth species of the extinct genus Protanthomyza Hennig, 1965 and extinct subfamily Protanthomyzinae Roháček, 1998. It belongs to a group lacking a ctenidial spine on fore femur. Based on analysis of morphological characters the relationships of the new species are discussed. Its discovery expands again the diversity of Anthomyzidae known to occur in the Eocene ‘Baltic amber forestʼ.

scholarly journals The Pleistocene-Holocene aquatic molluscs as indicators of the past ecosystem changes in Transbaikalia (Eastern Siberia, Russia)

2020 ◽  
Author(s):  
Olga K. Klishko ◽  
Evgeniy V. Kovychev ◽  
Maxim V. Vinarski ◽  
Arthur E. Bogan ◽  
Georgiy. A. Jurgenson
Keyword(s):  
Regional Climate ◽  
Far East ◽  
Marine Species ◽  
Drill Hole ◽  
Historical Change ◽  
Neolithic Period ◽  
Eastern Siberia ◽  
Alluvial Deposits ◽  
Fossil Species ◽  
The Past

ABSTRACTData on historical change of the Transbaikalian malacofauna in the Neopleistocene and Holocene is presented. Fossil shells from archeological excavations of the ancient settlements dating from the Neolithic period to Medieval and also from a drill hole of the Neopleistocene alluvial deposits were collected. In total nine species of bivalve molluscs from the families Margaritiferidae, Unionidae, Limnocardiidae, Glycymerididae, including one marine species, and two gastropod species from families Viviparidae and Planorbidae were identified. The time of the existence of each fossil species was determined by radiocarbon dating. It was found that the species ranged in age from more 50,000 and 2,080–1,210 years ago. Five species inhabited the Transbaikal region and are locally extirpated in the present. Their disjunctive ranges in the past included southern Europe and Western and Eastern Siberia to Transbaikalia and in the east to Far East and Primorye of Russia. The time of existence and extirpation of the thermophilic species of genera Adacna, Planorbis, Lanceolaria and Amuropaludina corresponds to cycles of the warming and cooling in Pleistocene and Holocene according to regional climate chronological scales. It was possible to separate these species as indicators of paleoclimate. Change of the species composition of the malacofauna of region connected with natural cycles of climatochrons in the Pleistocene and Holocene is the appearance of the climatogenic succession. In the course of this succession the disappearance of the stenothermal species occurred on a regional level and decreasing their global ranges.

Progress in the discovery of extant and fossil bryozoans

2020 ◽  
Vol 635 ◽  
pp. 71-79 ◽  
Author(s):  
M Pagès-Escolà ◽  
PE Bock ◽  
DP Gordon ◽  
S Wilson ◽  
C Linares ◽  
...  
Keyword(s):  
New Species ◽  
Marine Invertebrates ◽  
Marine Species ◽  
Past Century ◽  
Fossil Species ◽  
The Past ◽  
Extant Species ◽  
Technological Developments ◽  
Relative Productivity ◽  
Species Descriptions

The number of species that exist on Earth has been an intriguing question in ecology and evolution. For marine species, previous works have analysed trends in the discovery of extant species, without comparison to the fossil record. Here, we compared the rate of description between extant and fossil species of the same group of marine invertebrates, Bryozoa. There are nearly 3 times as many described fossil species as there are extant species. This indicates that current biodiversity represents only a small proportion of Earth’s past biodiversity, at least for Bryozoa. Despite these differences, our results showed similar trends in the description of new species between extant and fossil groups. There has been an increase in taxonomic effort during the past century, characterized by an increase in the number of taxonomists, but no change in their relative productivity (i.e. similar proportions of authors described most species). The 20th century had the most species described per author, reflecting increased effort in exploration and technological developments. Despite this progress, future projections in the discovery of bryozoan species predict that around 10 and 20% more fossil and extant species than named species, respectively, will be discovered by 2100, representing 2430 and 1350 more fossil and extant species, respectively. This highlights the continued need for both new species descriptions and taxonomic revisions, as well as ecological and biogeographical research, to better understand the biodiversity of Bryozoa.

Systematics, phylogeny and historical biogeography of the Pentagonaster clade (Asteroidea:Valvatida:Goniasteridae)

2007 ◽  
Vol 21 (4) ◽  
pp. 311 ◽  
Author(s):  
Christopher Mah
Keyword(s):  
Cladistic Analysis ◽  
Morphological Characters ◽  
Valid Species ◽  
Adult Size ◽  
Fossil Species ◽  
The Pacific ◽  
La Meseta Formation ◽  
Phylogenetic Hypotheses ◽  
Three New Species ◽  
Cope’S Rule

Morphology-based phylogenetic hypotheses developed for living and fossil goniasterid asteroids have provided several unique opportunities to study bathymetric and biogeographic shifts for an ecologically important group of prominent, megafaunal invertebrates. A cladistic analysis of 18 ingroup taxa employing 65 morphological characters resulted in a single most parsimonious tree. The tree supports assignment of the Atlantic Tosia parva (Perrier, 1881) and the Pacific Tosia queenslandensis Livingstone, 1932 to new, separate genera. The phylogenetic tree supports offshore to onshore bathymetric shifts between basal and derived taxa. The phylogeny is also consistent with historical events surrounding the separation of Antarctica from Australia and South Africa. Buterminaster Blake & Zinsmeister, 1988 from the Eocene La Meseta Formation, Antarctic Peninsula, was included in the phylogenetic analysis and is now supported as the only fossil species in the genus Pentagonaster Gray, 1840. Pentagonaster stibarus H. L. Clark, 1914 is separated from synonymy with P. dubeni Gray, 1847 and resurrected as a valid species. The new genus, Akelbaster, gen. nov., shows unusual new structures that resemble cribiform organs, although their function has not been determined. One specific ingroup lineage, including Tosia and Pentagonaster, attains a much larger adult size than those of its sister-taxa, suggesting that Cope’s rule may apply to asteroids within this clade. Pentagonaster and related genera are revised. Descriptions of four new genera and three new species are presented, including: Akelbaster novaecaledoniae, gen. nov., sp. nov., Ryukuaster onnae, gen. nov., sp. nov., Eknomiaster beccae, sp. nov., Pawsonaster parvus, gen. nov., comb. nov. and Anchitosia queenslandensis, gen. nov., comb. nov.

scholarly journals On the origin and evolution of a new anchialine stygobitic <i>Microceratina</i> species (Crustacea, Ostracoda) from Christmas Island (Indian Ocean)

2004 ◽  
Vol 23 (1) ◽  
pp. 49-59 ◽  
Author(s):  
Tadeusz Namiotko ◽  
Karel Wouters ◽  
Dan L. Danielopol ◽  
William F. Humphreys
Keyword(s):  
Sedimentary Facies ◽  
Marine Species ◽  
New Taxon ◽  
Fossil Species ◽  
Origin And Evolution ◽  
The North ◽  
Christmas Island ◽  
The Pacific ◽  
Tethys Ocean ◽  
The Baltic

Abstract. Marine species of the ostracod genus Microceratina Swanson (Cytheruridae, Eucytherurinae) were until now known only from their hard parts, the valves and carapaces, as no living animals have been described. Here we report the first living population, from a tropical anchialine cave. The description of the limbs and hard parts of this new taxon, M. martensi sp. nov., enhances our understanding of the origin and evolution of the cave-dwelling Microceratina – the new species and M. pseudoamfibola (Barbeito-Gonzalez) from an anchialine cave in Southern Italy – and clarifies their affinities with other Eucytherurinae species. Microceratina is known from both Recent and fossil species (Quaternary, Tertiary and Late Cretaceous) from shelf and deep-sea habitats and/or sedimentary facies, located in the Pacific Ocean (along the Australian and New Zealand coasts), the Mediterranean (Greece and Italy), the North Atlantic (British Isles) and the Baltic Sea (Rügen Island). This suggests that the Microceratina group spread through the expanding Tethys Ocean. The morphological traits of the two cave-dwelling species reflect their ecological conditions. Cave-dwelling Microceratina species appear to have originated from epigean shallow water species predisposed to colonize subterranean habitats.

Recognizing the species of Thuja (Cupressaceae) based on their cone and foliage morphology

Phytotaxa ◽  
2015 ◽  
Vol 219 (2) ◽  
pp. 101 ◽  
Author(s):  
Bin Sun ◽  
Yi-Ming Cui ◽  
Hai-Feng Wang ◽  
David Kay Ferguson ◽  
Qiao-Ping Xiang ◽  
...  
Keyword(s):  
North America ◽  
East Asia ◽  
Evolutionary History ◽  
Morphological Characters ◽  
Species Level ◽  
Fossil Species ◽  
Extant Species ◽  
History Of

Thuja, with 5 extant species, exhibiting a disjunctive distribution between East Asia (3 species) and North America (2 species), was investigated with respect to the morphological characters of foliage and cones by LM and SEM. Here we provide 2 keys to all 5 species of Thuja based on the cones and foliage respectively, which not  only can be used for identifying extant Thuja at the species level, but also have a great potential for recognizing and/or linking the fossil species to living ones, and further tracing the evolutionary history of the genus.

A morphometric diagnosis using continuous characters of Pinnunavis edkuensis, sp. nov. (Bacillariophyta: Bacillariophyceae), a brackish-marine species from Egypt

Phytotaxa ◽  
2015 ◽  
Vol 212 (1) ◽  
pp. 1 ◽  
Author(s):  
ROBERT K. EDGAR ◽  
AMAL I. SALEH ◽  
STACY M. EDGAR
Keyword(s):  
Surface Area ◽  
Species Recognition ◽  
Cladistic Analysis ◽  
Central Area ◽  
Distinct Group ◽  
Marine Species ◽  
Morphological Characters ◽  
Similar Species ◽  
Continuous Variables ◽  
Marine Habitats

Pinnunavis edkuensis is reported as a new diatom species from Egypt from brackish and marine habitats. Its description and diagnoses focus on 12 continuous morphological characters: valve breadth, valve mantle shape and surface area, axial-central area shape and surface area, axial area breadth, distal and proximal interstriae distances, striae slopes, magnitude and position of maximal slope along a semivalve transect, and inter-raphe distance. These characters are considered along their ontogenetic trajectories, using a size vector, by means of regression analyses. Shape was assessed using geometric morphometric methods. Diagnostic comparisons of P. edkuensis were made with P. yarrensis, for which a lectotype was chosen and Grunow’s unpublished description and drawings presented, and P. zalatii, a new name replacing the illegitimate name, Navicula aegyptiaca. P. edkuensis was demonstrated to be a distinct group compared to these two similar species using 11 of the 12 characters. The diagnoses emphasize species recognition by means of anova, regression and randomization analyses and specimen determination primarily by means of regression-based prediction intervals. Additional comments are made on the statistical nature of gaps associated with characters described by discrete or continuous variables, the importance of reporting sample sizes as part of diatom diagnoses and other comparisons, and the role of size in specimen comparability and taxon identification. The generic distinctness of Pinnunavis and Pinnularia is discussed based on a preliminary cladistic analysis of morphological characters.

Sign in / Sign up

Export Citation Format

Share Document