The family Desmatophocidae represents an early radiation of extinct pinnipeds that peaked in diversity during the middle Miocene. Although represented by abundant well-preserved fossils, the taxonomy and evolutionary relationships of this family remain poorly known. Late Miocene desmatophocids have been recorded, although none have been formally described, preventing a thorough appraisal of their decline and extinction. We report the discovery of a new species, Allodesmus demerei sp. nov., represented by a partial skeleton with cranium, mandibles, and axial skeleton, from the upper Miocene Montesano Formation of Washington, prompting reinterpretation of desmatophocid taxonomy, phylogeny, and extinction. Phylogenetic analysis (95 characters, 26 taxa) found strong support for monophyletic Desmatophocidae and Allodesmus. Desmatophocidae was found as sister to Phocidae with poor support. Allodesmus demerei was placed within the Allodesmus as the sister taxon to Allodesmus kernensis. The geochronologically young age (10.5–9.1 Mya) of Al. demerei establishes this species as the last of the desmatophocid seals. The middle Miocene peak in desmatophocid diversity coincides with the middle Miocene climatic optimum, suggesting that declining sea surface temperature played a role in their decline and extinction. Walruses diversified and increased in body size during the mid- to late Miocene as desmatophocids declined, suggesting some form of ecological displacement.
Robert W. Boessenecker and Morgan Churchill. 2018. The Last of the Desmatophocid Seals: A New Species of Allodesmus from the upper Miocene of Washington, USA, and a revision of the taxonomy of Desmatophocidae. Zoological Journal of the Linnean Society. zlx098. DOI: 10.1093/zoolinnean/zlx098
كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا
شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا
ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.
The titanosaurian sauropod dinosaur Mendozasaurus neguyelap is represented by several partial skeletons from a single locality within the Coniacian (lower Upper Cretaceous) Sierra Barrosa Formation in the south of Mendoza Province, northern Neuquén Basin, Argentina. A detailed revision of Mendozasaurus, including previously undocumented remains from the holotype site, allows us to more firmly establish its position within Titanosauria, as well as enabling an emended diagnosis of this taxon. Autapomorphies include: (1) middle and posterior cervical vertebrae with tall and transversely expanded neural spines that are wider than the centra, formed laterally by spinodiapophyseal laminae that are not connected with the pre- or postzygapophyses; (2) anterior caudal vertebrae (excluding anteriormost) with ventrolateral ridge-like expansion of prezygapophyses; and (3) humerus with divided lateral distal condyle on anterior surface. New remains demonstrate that the presacral vertebrae of Mendozasaurus were not unusually short anteroposteriorly, with this compression instead resulting from taphonomic crushing. Comparative studies of articulated pedes of other taxa allow us to interpret that the pedal formula of Mendozasaurus was 2-2-2-2-0, based on disarticulated bones that form a right hind foot. Mendozasaurus was incorporated into an expanded version of a titanosauriform-focussed phylogenetic data matrix, along with several other contemporaneous South American titanosaurs. The resultant data matrix comprises 84 taxa scored for 423 characters, and our phylogenetic analysis recovers Mendozasaurus as the most basal member of a diverse Lognkosauria, including Futalognkosaurus and the gigantic titanosaurs Argentinosaurus, Notocolossus, Patagotitan and Puertasaurus. Lognkosauria forms a clade with Rinconsauria (Muyelensaurus + Rinconsaurus), with Epachthosaurus and Pitekunsaurus recovered at the base of this grouping. A basal lithostrotian position for this South American clade is well supported, contrasting with some analyses that have placed these taxa outside of Lithostrotia or closer to Saltasauridae. The sister clade to this South American group is composed of an array of near-global taxa and supports the hypothesis that most titanosaurian clades were widespread by the Early–middle Cretaceous.
Figure 3. Life restoration of Mendozasaurus neguyelap based on the largest adult individual (femur length: 1530 mm). Artwork by Bernardo Gonzaléz Riga.
CONCLUSIONS
A detailed description of all remains pertaining to the early Late Cretaceous Argentinean titanosaurian sauropod dinosaur Mendozasaurus neguyelap enables a revised diagnosis for the genus. An expanded phylogenetic analysis recovers Mendozasaurus and several other taxa as part of a rich Lognkosauria that is placed within a diverse clade of South American lithostrotian titanosaurs. The sister clade to this South American group is composed of a near-global array of titanosaurs, which supports recent work that has argued for a widespread distribution of most titanosaurian clades by the Early–middle Cretaceous.
Bernardo J. Gonzàlez Riga, Philip D. Mannion, Stephen F. Poropat, Leonardo D. Ortiz David and Juan Pedro Coria. 2018. Osteology of the Late Cretaceous Argentinean Sauropod Dinosaur Mendozasaurus neguyelap: Implications for Basal Titanosaur Relationships. Zoological Journal of the Linnean Society.zlx103. DOI: 10.1093/zoolinnean/zlx103
كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا
شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا
ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.
Marine iguanas are among the most highly emblematic taxa of the Galápagos archipelago but have paradoxically received little attention from taxonomists. Amblyrhynchus is currently considered as a monotypic genus with a total of seven subspecies, A. cristatus cristatus, A. c. nanus, A. c. venustissimus, A. c. albemarlensis, A. c. hassi, A. c. mertensi and A. c. sielmanni. Although consensually followed for more than half a century, this classification does not properly reflect the main natural subdivisions inferred by more recent molecular evolutionary studies. We integrate population genetics, phylogenomics and comparative morphology to propose an updated taxonomy reflecting the evolutionary history of this group. We recognize a single species with 11 divergent population clusters at the level of subspecies: A. c. albermarlensis is recognized as a junior synonym of A. c. cristatus, and five new subspecies are described:Amblyrhynchus cristatus godzilla subsp. nov. (San Cristóbal-Punta Pitt),A. c. jeffreysi subsp. nov. (Wolf and Darwin), A. c. hayampi subsp. nov. (Marchena), A.c. trillmichi subsp. nov. (Santa Fé) and A. c. wikelskii subsp. nov. (Santiago). Recognizing the genetically divergent population clusters as subspecies also highlights several of them as management units in need of conservation efforts, such as the two subspecies endemic to San Cristóbal.
Keywords: Amblyrhynchus, Galápagos, integrative taxonomy, management units (MUs), Marine Iguana, new subspecies.
Fig 5: Overview of the phenotypic diversity among Amblyrhynchus cristatus subspecies: (A–C) Amblyrhynchus cristatus hassi from Santa Cruz (SFM 57412, 57407, 57408) (D–F) A. c. wikelskii subsp. nov. from Santiago (SFM 57447, 57448, 57446), (G–N) A. c. cristatus from Fernandina (OUMNH 6176, CAS 11512, 11511, 11510) and Isabela (SFM 64179, 11258, 65996, 65998), (O–Q) A. c. mertensi from San Cristóbal (SFM 57427, 57430, 57424), (R) A. c. trillmichisubsp. nov. (uncollected living specimen), (S) A. c. godzilla subsp. nov. (uncollected living specimen). HT: holotype, NT: neotype, PT: paratype.
Fig 6: Overview of the phenotypic diversity among Amblyrhynchus cristatus subspecies.(A–D) Amblyrhynchus cristatus venustissimus from Champion (CAS 11062) and Española (SFM 57415, 49853, 57413), (E–G) A. c. sielmanni (CAS 12565, SFM 57417, CAS 12570), (H–J) A. c. nanus from Genovesa (NHM 1946.8.30.20, SFM 57432, SFM 57445), (K–N) A. c. hayampi subsp. nov. from Marchena (CAS 12467, 12458, 12449, 12471), (O–U)A. c. jeffreysi subsp. nov. from Wolf (CAS 12690, CAS-SUR 4777, CAS 12693, CAS 12961) and Darwin (CAS 12694, 12696, 12695). HT: holotype, PT: paratype.
Fig 7: Photographic plate showing the different subspecies of Marine Iguana (living mature males exclusively). (A) Amblyrhynchus cristatus nanus, Genovesa, (B) A. c. hayampi subsp. nov., Marchena, (C) A. c. sielmanni, Pinta, (D, E) A. c. venustissimus, Española and Floreana, respectively, (F) A. c. trillmichi subsp. nov., Santa Fé, (G) A. c. hassi, Santa Cruz, (H) A. c. cristatus, Fernandina, (I) A. c. cristatus, Isabela, (J) A. c. mertensi, San Cristóbal, (K) A. c. godzilla subsp. nov., San Cristóbal, (L) A. c. wikelskii subsp. nov., Santiago.
Pictures from A. Ibañez (E, K), M. Krueger (A), H. Snell (B, D, H), S. Steinfartz (C, I, L), M. Vences (G, J), M. Vitousek (F). DOI: 10.1093/zoolinnean/zlx007
Fig 8: Distribution of the different subspecies of Galápagos marine iguanas according to the classification of Eibl-Eibesfeldt (1962) and the new taxonomy proposed herein. The orange dot on the southern coast of San Cristóbal represents the population of putative migrant specimens of A. c. venustissimus.
Etymology: The subspecific epithet hayampi refers to the word used to designate the common iguana in Kichwa (a Quechuan language representing one of the three official languages of Ecuador and currently spoken by a million people in South America).
Geographic distribution: Marchena and very likely its satellite islets (Fig. 8).
Etymology: The subspecies name is a patronym for Jeffreys Málaga, a ranger of the Galápagos National Park with an outstanding interest and enthusiasm for the fauna and flora of the Galápagos, and especially for marine iguanas. Jeffreys Málaga has been awarded several times ‘Guardaparque del Año,’ or Park Warden of the Year and has been an essential part of our team during several excursions to the Galápagos.
Geographic distribution: Wolf, Darwin (tentative assignment), Roca Redonda and very likely their satellite islets (Fig. 8).
Etymology: The subspecific epithet refers to the fictional saurian monster from the eponym movie franchise, Godzilla, created by Tomoyuki Tanaka (IMDb, 2016). Explicitly mentioned in the title sequence of the 1990s American remake (Emmerich, 1998), the physical appearance and swimming behaviour of marine iguanas were a significant source of inspiration to the creature′s designer (Patrick Tatopoulos, personal communication). The name is an invariable noun in apposition.
Geographic distribution: Northern (north-eastern) part of San Cristóbal and the satellite islets off the northern coast of San Cristóbal (Fig. 8).
Etymology: The subspecific epithet refers to Prof. Dr. Fritz Trillmich, a foremost biological researcher in Germany who has spent a lifetime working on the biology of the Galápagos islands. For many years Fritz Trillmich worked together with Martin Wikelski on the island of Santa Fé, where their research on the local population produced important insights into the behaviour and ecology of marine iguanas. In addition to undertaking his own research, Fritz Trillmich is Professor Emeritus of Behavioural Ecology at the University of Bielefeld where he continues to inspire and mentor generations of young researchers who will continue his legacy for years to come.
Geographic distribution: Santa Fé and very likely its satellite islets (Fig. 8).
Etymology: The subspecies name is a patronym for Prof. Dr. Martin Wikelski in recognition of his outstanding research on marine iguanas for several decades. Martin Wikelski has been fascinated by marine iguanas, which served as a study system for his behavioural and ecological research from his PhD onwards. He has published important papers on marine iguana ecology and conservation, for instance demonstrating the devastating effects of an oil spill on this species, and showing that marine iguanas can shrink in response to starvation induced by El Niño–based climate fluctuations.
Geographic distribution: Santiago, Rábida and very likely their satellite islets (Fig. 8).
Aurélien Miralles, Amy Macleod, Ariel Rodríguez, Alejandro Ibáñez, Gustavo Jiménez-Uzcategui, Galo Quezada, Miguel Vences and Sebastian Steinfartz. 2017. Shedding Light On the Imps of Darkness: An Integrative Taxonomic Revision of the Galápagos Marine Iguanas (Genus Amblyrhynchus). Zoological Journal of the Linnean Society. DOI: 10.1093/zoolinnean/zlx007
كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا
شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا
ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.
A molecular phylogeny is presented for 25 newly sequenced specimens of Gastropteridae. The present phylogeny was estimated by analysing the nuclear fragment 28S and two mitochondrial fragments cytochrome c oxidase I (COI) and 16S using maximum likelihood and Bayesian analyses. The distinctness of eight new species of Gastropteridae is supported by the molecular phylogeny and by subsequent Automatic Barcode Gap Discovery (ABGD) analysis. Morphological data also support the distinctness of these species. The following species are described here: Gastropteron minutum Ong and Gosliner sp. nov., Gastropteron multo Ong and Gosliner sp. nov., Sagaminopteron multimaculatum Ong and Gosliner sp. nov., Siphopteron vermiculum Ong and Gosliner sp. nov., Siphopteron flavolineatum Ong and Gosliner sp. nov., Siphopteron nakakatuwa Ong and Gosliner sp. nov., Siphopteron makisig Ong and Gosliner sp. nov. and Siphopteron dumbo Ong and Gosliner sp. nov. All of these species, spanning much of the phylogenetic tree of Gastropteridae, are found in a single, highly diverse region of the Philippines, the Verde Island Passage. These data support the hypothesis that this region is an area of high species richness as well as phyletic diversity. This study also supports strong correlation between morphological characters and the molecular phylogeny within the species of Siphopteron. Molecular studies also indicate the distinctness of specimens of Siphopteron quadrispinosum from Hawaii and those from the western Pacific. Western Pacific specimens should be regarded as Siphopteron leah. Siphopteron pohnpei is transferred to Sagaminopteron based on the molecular phylogeny. Other species complexes indicating the presence of geographically separated cryptic species indicate that further detailed study of this group is warranted and that hidden diversity is likely to increase with additional study.
Based on our morphological studies and molecular phylogeny, we confirmed that the eight new species hypothesized from our field observations of living animals all represent new species that are described here. Our molecular phylogeny also indicates the likely existence of geographically isolated cryptic species within previously classified specimens. Sagaminopteron psychedelicum from Madagascar appears to represent a cryptic species distinct from western Pacific populations, as is Sagaminopteron nigropunctatum from Saudi Arabia. Also, the western Indian Ocean specimen of S. tigrinum represents a cryptic species distinct from the western Pacific S. tigrinum. The lack of strong support for the monophyly of Gastropteron and Siphopteron requires additional study of taxa to determine whether greater support of these lineages is found when taxon sampling is increased. Also the phylogenetic and systematic relationship of Enotepteron needs to be examined when members of this taxon become available for molecular studies.
Elise Ong, Joshua M Hallas and Terrence M Gosliner. 2017. Like A Bat Out of Heaven: the Phylogeny and Diversity of the Bat-winged Slugs (Heterobranchia: Gastropteridae). Zoological Journal of the Linnean Society. 180(4); 755–789. DOI: 10.1093/zoolinnean/zlw018
كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا
شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا
ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.
We present the taxonomic description of Tarumaniidae, a new family of South American freshwater fishes including a new genus (Tarumania) and species (Tarumania walkerae) from the Central Amazon. The new taxon displays an extraordinary set of unique characteristics, which sets it apart from all other known bony fishes, either in South America or elsewhere. Tarumaniidae has reverse-imbricated scales on the head, 244 or more scales along the midlateral lateral series, an 11-chambered swimbladder extending along most of the body, an anteriorly deflectable pelvic fin and a platybasic skull, among other unusual traits. Although the general habitus of Tarumania gives little hint of its phylogenetic placement, examination of internal anatomy is largely elucidative concerning the main features of its relationships. For example, Tarumania has a complete Weberian apparatus, comprising a set of characteristics supporting its position in Otophysi and Ostariophysi. Additional comparative evidence corroborates its placement in the order Characiformes, including some trademark characiform synapomorphies such as the presence of a hypertrophied lagenar capsule. We conducted a phylogenetic analysis on the basis of previously published morphological evidence for Characiformes, with the inclusion of Tarumania and additional relevant taxa and characters. Results support the position of Tarumania as a part of the superfamily Erythrinoidea and sister group to the neotropical Erythrinidae. Our increased taxonomic representation of Erythrinidae in the matrices firmly corroborates Tarumania as sister group to the whole of Erythrinidae and not to a subgroup of that family. Tarumania walkerae is a predator, which inhabits vast leaf-litter deposits in the Rio Negro drainage, and is found deeply buried in isolated pools during the dry season. It is the first characiform with an anguilliform body shape and fossorial habits. The unprecedented combination of phenotypic traits, behaviour and habitat adds substantially to the larger picture of freshwater fish diversity. Although its microhabitat is difficult to sample, the geographical range of T. walkerae includes areas close to major urban centres and which have been ichthyologically surveyed for many years. The fact that a relatively large and highly distinctive fish such as Tarumania remained undiscovered until now is testimony to the still-incomplete state of knowledge of biodiversity in Amazonian waters.
Keywords: Amazon, Characiformes, Erythrinoidea, new genus, new species, phylogeny, systematics, taxonomy
Figure 1. Tarumania walkerae gen. et sp. nov., holotype, INPA 33737.
Figure 2. Tarumania walkerae gen. et sp. nov., holotype, INPA 33737. Figure 3. Live specimen, juvenile, of Tarumania walkerae, paratype, MZUSP 120543, shortly after collection. Arrow shows pelvic fins in anteriorly deflected position.
TAXONOMIC ACCOUNTS
Tarumaniidae fam. nov.
Tarumania gen. nov. Type species: Tarumania walkerae sp. nov. Etymology: From the river Tarumã-Mirim, tributary of the lower Rio Negro, first known locality of the new taxon. A noun in nominative singular. Gender feminine.
Tarumania walkerae sp. nov. Etymology: The specific name honours eminent limnologist Ilse Walker [Instituto Nacional de Pesquisas da Amazônia, Manaus (INPA)], not only for her lifelong contribution to the knowledge of Amazonian ecology but also for having collected the first (and for some years, only) known specimen. The epithet is a noun in the genitive feminine case. Geographical distribution: So far endemic to the Rio Negro basin, from the Rio Tarumã-Mirim, tributary to the Rio Negro near the city of Manaus, and from the Anavilhanas archipelago, on the main Rio Negro (Fig. 11). The two localities are ~60 km apart in straight line. Ecological notes All specimens known of Tarumania walkerae were collected deeply buried into massive leaf-litter deposits in isolated pools in the riparian forest. ....
Figure 2. Tarumania walkerae gen. et sp. nov., holotype, INPA 33737. Dorsal (a) and ventral (b) views of head. Figure 5. Tarumania walkerae, paratype, INPA 21603, lateral view of head showing reverse-imbricated scales. Specimen cleaned of superficial mucus.
Mário de Pinna, Jansen Zuanon, Lucia Rapp Py-Daniel and Paulo Petry. 2017. A New Family of Neotropical Freshwater Fishes from Deep Fossorial Amazonian Habitat, with A Reappraisal of Morphological Characiform Phylogeny (Teleostei: Ostariophysi). Zoological Journal of the Linnean Society. DOI: 10.1093/zoolinnean/zlx028
كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا
شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا
ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.
