scholarly journals Morphological evolution of the Muricinae

1992 ◽  
Vol 6 ◽  
pp. 211-211
Author(s):  
Daniel J. Miller
Keyword(s):  
Preliminary Analysis ◽  
Morphological Evolution ◽  
Shell Size ◽  
Western Atlantic ◽  
Marine Gastropods ◽  
Higher Taxa ◽  
The Family ◽  
History Of ◽  
Recent Species ◽  
Spiral Ribbing

The Muricidae constitute a taxonomically and morphologically diverse family of marine gastropods. The subfamily Muricinae is the largest in the family with over 180 Recent species recognized. Modern representatives typically are strongly sculptured and possess pronounced axial thickenings (varices) and varical spines. Early fossil representatives of the subfamily generally do not display the strong ornamentation that is characteristic of more modern forms. A study of Recent and fossil muricines in museum collections was made in order to document quantitatively the morphological evolution of this group. Morphometric data were obtained from oriented photographs, X- radiographs and actual specimens. These data were supplemented with limited measurements made from published plates. A preliminary analysis of these data has revealed the following:1. Neogene and Recent representatives are significantly more ornamented than those of the Cretaceous and Paleogene. Neogene and Recent forms typically have thicker varices and a greater number of well developed varical spines. The diversity of varix and spine morphologies also increases through time. Intervarical nodes also become more developed during the Neogene. A less pronounced trend towards increased spiral ornamentation is also indicated. Similar patterns are observed in both Europe and the western Atlantic and a preliminary analysis of Indo - Pacific fossil taxa suggests that the trend exists in this region as well.2. Although the appearance and diversification of higher taxa contributes to the above pattern (eg. Chicoreus, Murex), similar patterns are also observed within previously existing taxa.3. Elongated siphonal canals become more prevalent in the Neogene, although this pattern is largely the result of the diversification of new higher taxa (eg. Murex, Haustellum, Chicoreus (Siratus)).4. The range of gross shell morphologies described by Raup's coiling parameters increases during the evolution of the subfamily. Taxa with relatively high rates of whorl translation and relatively high whorl expansion rates appear later in the history of the group. However, at the subfamilial level, no obvious directional trend exists and this pattern may be explained as an increase in morphological variance. Nevertheless, the possibility that this pattern is the result of a number of independent unidirectional trends at a lower taxonomic level can not yet be discounted.5. Mean shell size within the family increases during the Cenozoic.6. The Miocene appears to be an interval of increased morphological and taxonomic diversification.Although the function of the diverse sculpture expressed in muricids remains poorly understood, features such as thick varices, spines and spiral ribbing are known to play a role in resisting durophagous predators. Increased size has also been implicated as a means of avoiding predation. It is likely that some varices and spines perform other functions as well and there are indeed morphologies within the Muricidae that do not comfortably fit an anti - predation interpretation. However, the directional patterns of morphological change observed in the Muricinae are broadly consistent with an “arms - race” scenario and strongly suggest that durophagous predation was an important driving force in the morphological evolution of this subfamily.

Homoplasy and extinction: the phylogeny of cassidulid echinoids (Echinodermata)

2019 ◽  
Vol 187 (3) ◽  
pp. 622-660 ◽  
Author(s):  
Camilla Souto ◽  
Rich Mooi ◽  
Luciana Martins ◽  
Carla Menegola ◽  
Charles R Marshall
Keyword(s):  
Evolutionary History ◽  
Cladistic Analysis ◽  
Future Studies ◽  
Novel Traits ◽  
The Family ◽  
Phylogenetic Resolution ◽  
History Of ◽  
Recent Species ◽  
Taxonomic Implications ◽  
High Diversity

Abstract Inclusion of fossils can be crucial to address evolutionary questions, because their unique morphology, often drastically modified in recent species, can improve phylogenetic resolution. We performed a cladistic analysis of 45 cassidulids with 98 characters, which resulted in 24 most parsimonious trees. The strict consensus recovers three major cassiduloid clades, and the monophyly of the family Cassidulidae is not supported. Ancillary analyses to determine the sensitivity of the phylogeny to missing data do not result in significantly different topologies. The taxonomic implications of these results, including the description of a new cassiduloid family and the evolution of some morphological features, are discussed. Cassiduloids (as defined here) most probably originated in the Early Cretaceous, and their evolutionary history has been dominated by high levels of homoplasy and a dearth of unique, novel traits. Despite their high diversity during the Palaeogene, there are only seven extant cassiduloid species, and three of these are relicts of lineages dating back to the Eocene. Future studies of the biology of these poorly known species, some of which brood their young, will yield further insights into the evolutionary history of this group.

scholarly journals State of research of the Osteichthyes fish related to coral reefs in the Honduran Caribbean with catalogued records

2019 ◽  
pp. 45-68
Author(s):  
Anarda Isabel Salgado Ordoñez ◽  
Julio Enrique Mérida Colindres ◽  
Gustavo Adolfo Cruz
Keyword(s):  
Coral Reef ◽  
Natural History ◽  
Coral Reefs ◽  
Recent Literature ◽  
Taxonomic Status ◽  
Western Atlantic ◽  
Secondary Sources ◽  
The Family ◽  
History Of ◽  
State Of Research

Research on Honduran coral reef fish has been isolated and scattered. A list of fish species related to coral reefs was consolidated to establish a compiled database with updated taxonomy. The study was conducted between October 2017 and December 2018. Using primary and secondary sources, all potential species in the Western Atlantic were considered, and their actual presence was confirmed using catalogued records published in peer-reviewed journals that included Honduras. In addition, the specimens kept in the Museum of Natural History of Universidad Nacional Autónoma de Honduras were added. Once the list was consolidated, the taxonomic status of each species was updated based on recent literature. A total of 159 species and 76 genera were registered in 32 families. The family with the most species was Labrisomidae with 27 species (17%). Five families had more than five 5 genera registered, while four 4 were represented by more than 16 species, which is equivalent to 42% genera and 51% species. Gobiidae was represented by 10 genera (13%) and 21 species (13%), of which two 2 were endemic: Tigrigobius rubrigenis and Elacatinus lobeli. In turn, Grammatidae was represented by one endemic species Lipogramma idabeli (1.8%). The species Diodon holocanthus and Sphoeroides testudineus represent the first catalogued records for Honduras.

Morphological conservatism of the family Naticidae (Gastropoda) through time: potential causes and consequences

Paleobiology ◽  
2021 ◽  
pp. 1-16
Author(s):  
Neha Sharma ◽  
Subhronil Mondal ◽  
Shiladri S. Das ◽  
Kanishka Bose ◽  
Sandip Saha
Keyword(s):  
Morphological Evolution ◽  
Taxonomic Status ◽  
Morphological Characters ◽  
Shell Morphology ◽  
Canonical Variate ◽  
The Family ◽  
Mode Of Life ◽  
History Of ◽  
Taxonomic Changes ◽  
The Individual

Abstract Taxonomic status of several members of the family Naticidae is extremely vague because of its simple shell morphology. Conventional taxonomic classification schemes suggest that most of the morphological characters tend to be homoplastic and exhibit convergence. Such morphological convergence complicates naticid taxonomy and makes it difficult to understand the evolutionary history of this group; several unrelated taxa are often misidentified as naticids, thereby exaggerating the actual diversity of this group. Here, we employ a standard landmark-based approach to understand the pattern of morphological evolution of this family. Ordination methods such as principal components analysis and canonical variate analysis were used to create morphospaces, and disparity was quantified using variance and range. Our results reveal that when naticids are compared with their sister taxon, Ampullinidae, the two families show significant differences in their average shapes, despite their superficial resemblances. Among naticids, although the mean shapes of the individual subfamilies are different, overall, the family Naticidae has displayed extreme morphological conservatism from the Jurassic to the Holocene. Interestingly, this conservatism has been unaffected by taxonomic changes—neither the extinction of the subfamily Gyrodinae nor the appearance of the subfamily Sininae affected this morphological conservatism. Naticids have always shown strong ecological preference toward an infaunal mode of life and strict behavioral selectivity in handling and preying upon infaunal organisms, and this ecological and behavioral conservatism could have enabled them to diversify without undergoing a change in their basic Bauplan.

scholarly journals The natural history of Calyptraea aurita (Reeve, 1859) from Southern Chile (Gastropoda, Calyptraeidae)

ZooKeys ◽  
2018 ◽  
Vol 798 ◽  
pp. 1-22
Author(s):  
Jorge Holtheuer ◽  
Cristian Aldea ◽  
Dirk Schories ◽  
Carlos Gallardo
Keyword(s):  
Egg Mass ◽  
Depth Range ◽  
Shell Size ◽  
Southeastern Pacific ◽  
The Family ◽  
History Of ◽  
Planktotrophic Larvae ◽  
Hard Bottom Communities ◽  
Hard Substrates ◽  
Growth And Reproduction

Hard bottom communities of the Reloncaví Estuary and adjacent areas, Region de los Lagos, Chile (42°S), were studied between 2008 and 2011. All hard substrates between the lower intertidal and 25 m depth were dominated by the calyptraeid gastropods,CrepipatelladilatataandC.fecunda. Epibenthic coverage of the hard bottoms markedly decreased further down with the exception of vertical cliffs. In a depth range between 26 to 48 m repeatedly dense patches of another calyptraeid species,Calyptraeaaurita(Reeve, 1859), were observed. Densities reached up to 1475 individuals m-2and covered up to 50 % of the rock surfaces. In shallower depthsC.auritawas not present. However, despite its huge abundance,C.auritahas not been documented for more than 150 years in the southeastern Pacific, being described superficially by Reeve, through only shell characteristics. Here, we redescribe and compare it with other members of the family Calyptraeidae through characteristics of shell, radula, and soft parts, including also details of the egg mass and intracapsular development of their embryos. Males were mobile and females sessile. Shell size ranged from 6.6 to 12.4 mm for immature individuals, from 10.6 to 24.9 mm for males, 15.1 to 25.9 mm for intersex individuals, and from 21.0 to 39.6 mm for females. Up to three individuals stacked together were found, always presenting a female at the base with up to a maximum of two male individuals above. Laboratory studies demonstrated thatC.auritahas an indirect larval development, liberating planktotrophic larvae with a bilobed ciliated velum into the water column. A transplantation experiment demonstrated that survival, growth, and reproduction ofC.auritais also possible in depths shallower than its normal distribution. The geographic distribution ofC.aurita, was previously only known as being from Valparaíso (33°S) and is now extended down to the Reloncaví Sound (41°S).

A new species of Thorecta (Porifera: Demospongiae) from the western Atlantic, with remarks on the taxonomy of the genus

2010 ◽  
Vol 90 (4) ◽  
pp. 775-782 ◽  
Author(s):  
Josivete P. Santos ◽  
Suzane M. da Silva ◽  
Paulo H.O. Bonifácio ◽  
Eduardo L. Esteves ◽  
Ulisses S. Pinheiro ◽  
...  
Keyword(s):  
New Species ◽  
Valid Species ◽  
Northern Coast ◽  
Western Atlantic ◽  
Eastern Brazil ◽  
Potiguar Basin ◽  
The Family ◽  
North Eastern ◽  
History Of ◽  
A New Species

The family Thorectidae includes 23 valid genera and 130 species, characterized by the presence of laminated fibres and diplodal choanocytye chambers. Currently the genus Thorecta comprises approximately 20 valid species, distributed mainly in the Indo-Pacific. We describe here a new species of Thorecta that is the only valid species of the genus described in the Atlantic Ocean so far. Samples were collected by trawling on board of the RV ‘Astro Garoupa’ in Potiguar Basin, on the northern coast of Rio Grande do Norte State, north-eastern Brazil. Thorecta atlantica sp. nov. is greyish-brown to dark brownish-grey and presents a distinctive globular or clavulate shape, with 1–2 large apical oscules that open to deep atria. It was found between 61 and 160 m depth. A literature survey suggests that many species referred to Thorecta should be relocated to different genera due to absence of diagnostic characters, and that the genus Thorecta should group only 11 species: T. carteri, T. marginalis, T. prima, T. lata, T. farlovi, T. meandrina, T. polygona, T. reticulata, T. tuberculata, T. vasiformis and T. atlantica sp. nov. The tortuous history of the genus is an example of the damage that poorly-described species can cause to classification. Detailed descriptions of fresh material, well illustrated by photographs and including as many characters as possible, are essential tools for the clarification of the systematics of Thorecta in the future.

The Prevalence of Hereditary Antithrombin-III Deficiency in Patients with a History of Venous Thromboembolism

1985 ◽  
Vol 54 (04) ◽  
pp. 744-745 ◽  
Author(s):  
R Vikydal ◽  
C Korninger ◽  
P A Kyrle ◽  
H Niessner ◽  
I Pabinger ◽  
...  
Keyword(s):  
Venous Thrombosis ◽  
Antithrombin Iii ◽  
Positive Family History ◽  
Normal Range ◽  
The Family ◽  
History Of ◽  
Antithrombin Iii Deficiency ◽  
Recurrent Venous Thrombosis ◽  
Antithrombin Iii Activity ◽  
Slight Deficiency

SummaryAntithrombin-III activity was determined in 752 patients with a history of venous thrombosis and/or pulmonary embolism. 54 patients (7.18%) had an antithrombin-III activity below the normal range. Among these were 13 patients (1.73%) with proven hereditary deficiency. 14 patients were judged to have probable hereditary antithrombin-III deficiency, because they had a positive family history, but antithrombin-III deficiency could not be verified in other members of the family. In the 27 remaining patients (most of them with only slight deficiency) hereditary antithrombin-III deficiency was unlikely. The prevalence of hereditary antithrombin-III deficiency was higher in patients with recurrent venous thrombosis.

Can a Narcissist Ever Marry?: James Fisher and The Uninvited Guest

2014 ◽  
Vol 4 (1) ◽  
Author(s):  
Brett Kahr
Keyword(s):  
Clinical Material ◽  
Couple Relationships ◽  
Cocktail Party ◽  
False Self ◽  
Winter's Tale ◽  
Pathological Narcissism ◽  
The Family ◽  
History Of ◽  
Marital Partners

Few books in the burgeoning field of couple psychoanalysis have garnered as much admiration as James Fisher's The Uninvited Guest: Emerging from Narcissism towards Marriage. In this memorial essay, the author pays tribute to the late Dr Fisher and to his perennial book which explores the ways in which pathological narcissism, among other factors, inhibit the development of spousal intimacy, often destroying partnerships entirely. The author describes the creative way in which Fisher drew upon great works of literature, most notably William Shakespeare's A Winter's Tale, and T. S. Eliot's The Cocktail Party, as well as long-forgotten clinical material from Fisher's predecessors at the Family Discussion Bureau (forerunner of the Tavistock Centre for Couple Relationships), in order to understand the ways in which marital partners struggle with false self couplings. The author assesses the importance of Fisher's contribution in the context of the history of couple psychoanalysis.

Faktor-Faktor Determinan yang melatar belakangi Kehamilan Remaja di Desa Pandansari Kecamatan Poncokusumo Kabupaten Malang

2020 ◽  
Vol 7 (2) ◽  
pp. 247-255
Author(s):  
Maria Magdalena Setyaningsih ◽  
Emy Sutiyarsih
Keyword(s):  
Sex Education ◽  
Teen Pregnancy ◽  
Teenage Pregnancy ◽  
Well Being ◽  
Case Control ◽  
Control Group ◽  
Case Group ◽  
The Family ◽  
History Of ◽  
First Time

Kehamilan remaja adalah kehamilan yang terjadi pada remaja berusia kurang dari 20 tahunan. Kehamilan remaja memberikan banyak kerugian bagi kesehatan, mental dan psikologis, kesejahteraan ekonomi dan peluang karier, kemiskinan dan prospek kehidupan masa depan remaja. Tujuan penelitian mengidentifikasi faktor determinan yang melatarbelakangi terjadinya kehamilan remaja. Jenis penelitian adalah penelitian analitik kategorik jenis survei kuantitatif dengan desain case control. Populasi semua perempuan yang bertempat tinggal di wilayah dusun Wonosari, Sukosari, dan Krajan Pandansari dan pernah/sedang hamil pertama kali pada usia kurang dari 20 tahun. Teknik pengambilan sampel cluster random sampling besar sampel 73. Berdasarkan hasil model akhir analisis multivariat, diketahui bahwa variabel pendidikan, riwayat kehamilan remaja pada keluarga dan usia menikah merupakan variabel yang berhubungan dengan kejadian kehamilan remaja setelah dikontrol oleh variabel akses informasi, responden berpendidikan rendah memiliki peluang 20,8 kali lebih tinggi, responden yang memiliki riwayat kehamilan remaja pada keluarga memiliki peluang 14,9 kali lebih tinggi, responden yang menikah pada usia <20 tahun memiliki peluang 12,1 kali lebih tinggi, responden dengan pemahaman yang kurang baik terkait penggunaan kondom memiliki peluang 5,9 kali lebih tinggi untuk terjadi kehamilan remaja. Oleh karena itu perlu dibangun karakter buiding, sosial karakter suport untuk para ibu remaja dan keluarga sehingga terbangun interaksi yang baik dalam keluarga yang dilandasi dengan pendidikan dan pemahaman yang baik tentang Pendidikan seksualitas. Teen pregnancy is a pregnancy that occurs in adolescents aged less than 20 years old. Teen pregnancy provides many disadvantages for health, mental, psychological, economic well-being, career opportunities, poverty, and the future life. The aim of the study was to identify the determinants underlying teen pregnancy incidence. This study was a quantitative study with categorical analytic method. The study design used a case control with two comparison groups. The groups were control group and case group. The population in this study was all women who lived in the Wonosari, Sukosari, and Krajan Pandansari district and had or were pregnant for the first time at the age of less than 20 years old. Seventy three respondents were recruited using cluster sampling technique. The case group consists of women who were or had pregnant for the first time at the age of less than 20 years old and their children are currently aged ≤ 1 years old. The control group consists of women who were pregnant for the first time at the age of > 20 years old. The data was collected using a questionnaire. The findings showed that education, history of teen pregnancy in family and the age of marriage were related to the incidence of teen pregnancy after being controlled by information access. Low-educated respondents had 20.8 times higher chance of experiencing teen pregnancy; respondents with a history of teen pregnancy in the family had 4.9 times higher chance of experiencing teen pregnancy; respondents who were married at the age of < 20 years old had 12.1 times higher chance of experiencing teen pregnancy; respondents with poor understanding of condom use had 5.9 times higher chance of teenage pregnancy. In conclusion, the findings suggest to build good interactions in the family based on education and a good understanding of sex education.

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