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Saturday, December 3rd, 2022
| Time | Event | ||||||
| 3:01a | [Paleontology • 2022] Chrysemys corniculata • A New Species of Chrysemys (Testudines: Emydidae: Deirochelyinae) from the latest Miocene-Early Pliocene of Tennessee, USA and Its Implications for the Evolution of Painted Turtles
Abstract Chrysemys, commonly known as painted turtles, have the largest native biogeographic range of all North American turtles. The presence of a new species, Chrysemys corniculata sp. nov., in the Late Hemphillian-Early Blancan North American Land Mammal Age (latest Miocene-Early Pliocene) of Tennessee provides further data on the evolution of Chrysemys, deirochelyines and emydids. The new fossil species lies basally in Deirochelyinae and suggests that either Chrysemys represents a basal deirochelyine morphology and is one of the oldest genera in the family, or that similar basal morphologies have evolved multiple times throughout deirochelyine evolution. Its occurrence at the same time as Chrysemys picta, during the Hemphillian-Early Blancan, a time of high biodiversity in emydid turtles, suggests either multiple species of Chrysemys during the Late Hemphillian-Early Blancan (at least one in the mid-west and one farther east), or multiple lineages with basal morphologies during this time. Early fossil deirochelyines occur after the greenhouse conditions of the Eocene and the Mid-Miocene Climatic Optimum. Vicariance led to deirochelyines becoming more speciose, including the occurrence of C. corniculata, after the Mid-Miocene Climatic Optimum, potentially suggesting cooler temperatures aided in the evolution of the subfamily and their speciation during the Hemphillian and into the Early Blancan.  Steven E. Jasinski. 2022. A New Species of Chrysemys (Emydidae: Deirochelyinae) from the latest Miocene-Early Pliocene of Tennessee, USA and Its Implications for the Evolution of Painted Turtles. Zoological Journal of the Linnean Society, zlac084. DOI: 10.1093/zoolinnean/zlac084 | ||||||
| 3:13a | [Paleontology • 2022] Cryptovaranoides microlanius • A Triassic Crown Squamate
Abstract Mammals, birds, and squamates (lizards, snakes, and relatives) are key living vertebrates, and thus understanding their evolution underpins important questions in biodiversity science. Whereas the origins of mammals and birds are relatively well understood, the roots of squamates have been obscure. Here, we report a modern-type lizard from the Late Triassic of England [202 million years (Ma)], comprising a partial skeleton, skull, and mandibles. It displays at least 15 unique squamate traits and further shares unidentatan and anguimorph apomorphies. The new discovery fixes the origin of crown Squamata as much older than had been thought, and the revised dating shows substantial diversification of modern-type squamates following the Carnian Pluvial Episode, 232 Ma ago.
 Infraclass DIAPSIDA Osborn, 1903 PAN-SQUAMATA sensu Gauthier and de Queiroz, 2020 SQUAMATA sensu de Queiroz and Gauthier, 2020 Cryptovaranoides gen. nov Cryptovaranoides microlanius n. gen., n. sp. Etymology— The genus name Cryptovaranoides is derived from the Greek word crypto, “hidden,” new Latin varan (from Arabic Waran meaning “dragon-lizard”), and the Greek suffix oides meaning “like.” The generic name is thus “hidden, lizard-like” (animal), referring to the fact that this fossil has remained unrecognized in a collection for nearly 70 years and that it was a small lizard-like animal (skull length maximum about 30 mm), living on karst limestone, perhaps hiding in the grykes (crevices). The species name microlanius derives from the Greek “micro” = small and Latin “lanius” meaning butcher. The recurved blade-like teeth demonstrate that the animal was a small efficient predator that could capture and immobilize prey quickly. Holotype—NHMUK PV R36822, a partly articulated anterior skeleton and associated partial skull and lower jaws preserved on and in the red matrix of a small block of conglomeratic limestone. The left mandible and a partial skull (Fig. 1, A and B), including both maxillae and associated bones, are close to the articulated partial skeleton. .... Locality and age—Triassic fissure deposit in Carboniferous Limestone, Cromhall Quarry, Tortworth, Gloucestershire, United Kingdom. Age is Rhaetian, probably late Rhaetian (equivalent of Cotham Member, Lilstock Formation), 201.6 to 201.8 Ma. Diagnosis—Characterized by the following apomorphies: (i) maxillary and dentary with frequently replaced conical, pleurodont recurved teeth (Figs. 1, A to C, E, and F, 2, C and D, 3, A to G, and 4A) displaying labio-lingually compressed apices (upper part of the crown) and a prominent sharp carina on mesial and distal edges (Fig. 3, F and G). The mesial compressed region is somewhat more pronounced than the distal, and overall cross section of compressed region is oculiform-lanceolate. The mesial region of mid and posterior maxillary teeth develops a pronounced blade-like flange. ....   David I. Whiteside, Sofía A. V. Chambi-Trowell and Michael J. Benton. 2022. A Triassic Crown Squamate. SCIENCE ADVANCES. 8(48). DOI: 10.1126/sciadv.abq8274 Fossil discovery in storeroom cupboard shifts origin of modern lizard back 35 million years | ||||||
| 7:43a | [Paleontology • 2022] Ancient Antarctica: the early Evolutionary History of Nothofagus
ABSTRACT The genus Nothofagus (southern beech) has an extensive fossil record and extant species exclusively distributed in the Southern Hemisphere. It is divided into four subgenera widespread across eastern Australasia and southern South America. The origin and evolution among closely related species remain an important question in palaeontology. The goal of this work is to reconstruct the biogeography of Nothofagus incorporating a complete leaf fossil dataset to better understand its origin, diversification, and colonisation history. The most ancient fossil leaves were discovered in Antarctica and are herein included for the first time into phylogenetic and biogeographic analyses. We employed statistical biogeographic methods implemented in BioGeoBEARS to estimate ancestral areas. The results support a high probability that the ancient ancestor of Nothofagus may have originated in Antarctica during the Late Cretaceous which is also supported by the fossil pollen record found in the Antarctic Peninsula. Subgenera Fuscospora and Lophozonia resulted in the most ancient clades, while the subgenera Nothofagus and Brassospora evolved later (Palaeogene). Our model supports that subgenera divergences were characterised by both dispersal and vicariance events from the Late Cretaceous to the early–middle Eocene. KEYWORDS: Nothofagaceae, fossil, leaves, phylogeny, biogeography, southern beech  Bárbara Vento, Federico Agrain and Griselda Puebla. 2022. Ancient Antarctica: the early Evolutionary History of Nothofagus. Historical Biology: An International Journal of Paleobiology. DOI: 10.1080/08912963.2022.2150549 twitter.com/AsiaPaleoFloras/status/1598274535325069312 | ||||||
| 9:39a | [Botany • 2022] Capture of Mammal Excreta by Nepenthes is An Effective Heterotrophic Nutrition Strategy
Abstract Background and aims: While isotopic enrichment of nitrogen (15N) and carbon (13C) is often used to determine whether carnivorous plant species capture and assimilate nutrients from supplemental sources such as invertebrate prey or mammal excreta (heterotrophic nutrition), little is known about how successful the different strategies deployed by carnivorous plants are at obtaining supplemental nutrition. The collection of mammalian faeces by Nepenthes (tropical pitcher plants) is the result of a highly specialised biological mutualism that results in heterotrophic nitrogen gain; however, it remains unknown how effective this strategy is in comparison to Nepenthes species not known to collect mammalian faeces. Methods: We examined how isotopic enrichment varied in the diverse genus Nepenthes, among species producing pitchers for invertebrate capture and species exhibiting mutualisms for the collection of mammal excreta. Enrichment factors were calculated from δ 15N and δ 13C values from eight Nepenthes species and naturally occurring hybrids along with co-occurring reference (non-carnivorous) plants from three mountain massifs in Borneo: Mount Kinabalu, Mount Tambuyukon, and Mount Trus Madi. Results: All Nepenthes examined, except N. edwardsiana, were significantly enriched in 15N compared to co-occurring non-carnivorous plants, and 15N enrichment was more than two-fold higher in species with adaptations for the collection of mammal excreta compared with other Nepenthes. Conclusions: The collection of mammal faeces clearly represents a highly effective strategy for heterotrophic nitrogen gain in Nepenthes. Species with adaptations for capturing mammal excreta occur exclusively at high elevation (i.e., are typically summit-occurring) where previous studies suggest invertebrate prey are less abundant and less frequently captured. As such, we propose this strategy may maximise nutritional return by specialising towards ensuring the collection and retention of few but higher-value N sources in environments where invertebrate prey may be scarce. Keywords: Carnivorous plants, Nepenthes, non-core Caryophyllales, nutrient-acquisition strategy, functional morphology, ultramafic, investment in carnivory   Adam T. Cross, Antony van der Ent, Miriam Wickmann, Laura M Skates, Sukaibin Sumail, Gerhard Gebauer and Alastair Robinson. 2022. Capture of Mammal Excreta by Nepenthes is An Effective Heterotrophic Nutrition Strategy. Annals of Botany. mcac134. DOI: 10.1093/aob/mcac134  | ||||||
| 1:31p | [Botany • 2022] Curcuma nakhonphanomensis (Zingiberaceae: Zingibereae) • A New Species from the lower Mekong River Basin, northeastern Thailand
Abstract Curcuma nakhonphanomensis Boonma, Saensouk & P. Saensouk sp. nov. (Zingiberaceae: Zingibereae) was distributed in Nakhon Phanom Province, northeastern Thailand. The morphological characteristic of this species makes it fall into Curcuma subgenus Ecomata, due to the presence of epigynous glands, lack of coma bracts and bracts fused only at the base, and production of open-form of flowers. This plant did not match any existing species after careful morphological examination and comparison of all allied species in the genus Curcuma, especially in subgenus Ecomata. Therefore, we described it here as a new species to science in the name of Curcuma nakhonphanomensis Boonma, Saensouk & P. Saensouk. The specific epithet is named according to the province's name of the type locality. The morphological characteristics description, illustrations, vernacular name, ecology, phenology, distribution, utilization, conservation status, and map of distribution are present. The comparison table of the new species and its allies species, including a revised key to 41 species of Curcuma subgenus Ecomata is provided. Keywords: Curcuma nakhonphanomensis, Ecomata, Nakhon Phanom Province, taxonomy, Zingiberaceae
Curcuma nakhonphanomensis Boonma, Saensouk & P. Saensouk sp. nov. Subgen. Ecomata The new species is similar to Curcuma peramoena Souvann. & Maknoi but differ in having leaf sheath, ligule, and petiole green with a brownish red tinge, lamina broader 8–13 cm wide, leaves base cordate to slightly rounded, leaves midrib usually with red patches, pubescent on both surfaces; peduncle pubescent; fertile bracts pubescent; flower 6.2–6.5 cm long; calyx 22–25 mm long; corolla lobes sparsely hairy; labellum obovate, labellum apex trilobed, sides lobe rounded, middle lobe emarginate with an acute tip, incision up to 12 mm long, labellum white with yellow distal half of median band to yellowish orange, white basal half median band, with dark red lines in the mid lobes and dark red lines along both sides of the white median band from basal to 1/4 of the labellum length; staminodes asymmetrical broadly elliptic-rhombic; filament c. 6 × 4 mm, white; anther 11–12 mm long; spurs c. 2 mm long; crest c. 2 mm long; epigynous glands c. 8 mm long, apex sharp. Piyaporn Saensouk, Thawatphong Boonma and Surapon Saensouk. 2022. Curcuma nakhonphanomensis (Zingiberaceae), A New Species from the lower Mekong River Basin, northeastern Thailand. Biodiversitas. 23: 6040-6048. https://smujo.id/biodiv/article/view/12165  |
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