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Tuesday, November 9th, 2021
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| 1:47a | [Paleontology • 2021] Scutellosaurus lawleri • The Anatomy and Palaeobiology of the early Armoured Dinosaur (Ornithischia: Thyreophora) from the Kayenta Formation (Lower Jurassic) of Arizona, USA
Abstract The armoured dinosaurs, Thyreophora, were a diverse clade of ornithischians known from the Early Jurassic to the end of the Cretaceous. During the Middle and Late Jurassic, the thyreophorans radiated to evolve large body size, quadrupedality, and complex chewing mechanisms, and members of the group include some of the most iconic dinosaurs, including the plated Stegosaurus and the club-tailed Ankylosaurus; however, the early stages of thyreophoran evolution are poorly understood due to a paucity of relatively complete remains from early diverging thyreophoran taxa. Scutellosaurus lawleri is generally reconstructed as the earliest-diverging thyreophoran and is known from over 70 specimens from the Lower Jurassic Kayenta Formation of Arizona, USA. Whereas Scutellosaurus lawleri is pivotal to our understanding of character-state changes at the base of Thyreophora that can shed light on the early evolution of the armoured dinosaurs, the taxon has received limited study. Herein, we provide a detailed account of the osteology of Scutellosaurus lawleri, figuring many elements for the first time. Scutellosaurus lawleri was the only definitive bipedal thyreophoran. Histological studies indicate that it grew slowly throughout its life, possessing lamellar-zonal tissue that was a consequence neither of its small size nor phylogenetic position, but may instead be autapomorphic, and supporting other studies that suggest thyreophorans had lower basal metabolic rates than other ornithischian dinosaurs. Faunal diversity of the Kayenta Formation in comparison with other well-known Early Jurassic-aged dinosaur-bearing formations indicates that there was considerable spatial and/or environmental variation in Early Jurassic dinosaur faunas. Keywords: Ornithischia, Jurassic, Scutellosaurus lawleri, Dinosauria, Thyreophora, Kayenta Formation
Benjamin T. Breeden, Thomas J. Raven, Richard J. Butler, Timothy B. Rowe and Susannah C. R. Maidment. 2021. The Anatomy and Palaeobiology of the early Armoured Dinosaur Scutellosaurus lawleri (Ornithischia: Thyreophora) from the Kayenta Formation (Lower Jurassic) of Arizona. Royal Society Open Science. DOI: 10.1098/rsos.201676 | ||||||
| 1:51a | [Ichthyology • 2021] Cirrhilabrus apterygia • Redescription of Conniella apterygia Allen and Its Reassignment in the Genus Cirrhilabrus Temminck & Schlegel (Teleostei: Labridae), with Comments on Cirrhilabrin Pelvic Morphology
Abstract Conniella apterygia is redescribed from re-examination of the holotype, two paratypes, and six additional specimens. The genus is closely allied to Cirrhilabrus, sharing similarities in general morphological and meristic details, but is separated from Cirrhilabrus and most other labrid fishes in lacking pelvic fins and a pelvic girdle. Recent molecular phylogenetic studies have provided strong evidence for the deep nesting of Conniella within Cirrhilabrus, contradicting its generic validity and suggesting that the loss of pelvic elements is autapomorphic. Consequently, the species is redescribed and assigned to the genus Cirrhilabrus, as Cirrhilabrus apterygia new combination. The pelvic morphologies of related cirrhilabrin labrids are discussed, and a new synapomorphy is identified for Paracheilinus. Key words: coral-reef fishes; taxonomy; ichthyology; apomorphy; fairy wrasse; morphology 
Cirrhilabrus apterygia (Allen, 1983), new combination Connie’s Wrasse Other names: Mutant Wrasse; Rowley Shoals Wrasse Diagnosis. A species of Cirrhilabrus distinguished from all other congeners based on the following combination of colouration and morphological characters: absence of pelvic fins and pelvic girdle; lateral line with 21–26 pored scales (16–17 in the dorsoanterior series, 5–9 in the posterior peduncular series); caudal fin rhomboidal to lanceolate in males; both sexes with eight to ten stripes, purple in life and in preservation; preopercle purple in preservation. Etymology. Allen (1983) named the species apterygia, meaning “without fins,” in reference to the distinctive lack of pelvic fins and associated elements. To be treated as a noun in apposition. We retain the use of Connie’s Wrasse as the preferred common name, after Connie Lagos Allen, wife of the second author, for whom the junior synonym Conniella was named. The species is also commonly referred to as the mutant wrasse, alluding to its atypical pelvic morphology, as well as the eponymous Rowley Shoals Wrasse, after its type locality.
 Yi-Kai Tea, Gerald R. Allen, Christopher H. R. Goatley, Anthony C. Gill and Benjamin W. Frable. 2021. Redescription of Conniella apterygia Allen and Its Reassignment in the Genus Cirrhilabrus Temminck and Schlegel (Teleostei: Labridae), with Comments on Cirrhilabrin Pelvic Morphology. Zootaxa. 5061(3);493-509. DOI: 10.11646/zootaxa.5061.3.5  | ||||||
| 4:16a | [Botany • 2021] Ctenium bennae (Poaceae: Chloridoideae) • A New Rheophytic Species from Guinea-Conakry
Summary Ctenium bennae Xanthos is described and illustrated as the only rheophytic species in the genus. The new species is known from a single waterfall on the Benna Plateau, at the border between Forecariah and Kindia Prefectures in Guinea Conakry. Ctenium bennae is here assessed as Near Threatened according to the categories and criteria of IUCN. Key Words: Africa, rheophyte, taxonomy
Ctenium bennae Xanthos sp. nov. Type: Guinea Conakry, border between Forécariah and Kindia Prefectures, slopes of Benna Plateau above Gombokori Village, ... RECOGNITION. Ctenium bennae has the most reduced spikelet structure among the African species of Ctenium, with the first two florets reduced completely to awns (i.e. lemma body absent) and the fourth floret absent. Only the third floret is fully developed. Affinities occur with C. sesquiflorum but this has the first and fourth floret absent and the presence of a second rudimentary lemma. Specimens of C. newtonii var. newtonii at K have been recorded with no fourth floret but even these specimens have rudimentary first and second lemmas, and the inflorescence has 1 spike; not 3 – 7 as in C. bennae. The species is the only rheophytic representative in the genus. A comparison of C. bennae with morphologically similar species from West Africa is given in Table 1. HABITAT. Ctenium bennae is a rheophytic species collected on rocks in the rapids of a permanent stream that flows over sandstone bedrock in gallery forest. ETYMOLOGY. The epithet is named after the type locality of the species, Benna Plateau. CONSERVATION STATUS. Ctenium bennae is known only from one site, the type locality, Benna Plateau. There are currently no discernible threats to this site, however a single threatening event could eliminate this species globally. The Area of Occupancy (AOO) is 4 km2, which was calculated using GeoCat (Bachman et al. 2011) using 2 × 2 km2 grid cells. Assessed against the guidelines for IUCN, this species does not quite meet the threshold for threatened taxa and is here assessed as Near Threatened (NT). Martin Xanthos, Gbamon Konomou, Pepe M. Haba and Xander M. van der Burgt. 2021. Ctenium bennae (Poaceae; Chloridoideae), A New Rheophytic Species from Guinea-Conakry. Kew Bulletin. DOI: 10.1007/s12225-021-09989-6 | ||||||
| 2:03p | [Paleontology • 2021] Kuru kulla • A New Dromaeosaurid (Coelurosauria: Maniraptora) from Khulsan, Central Mongolia 
Abstract Dromaeosaurid theropods represent a rare but important clade of nonavialan dinosaurs. Their close evolutionary relationship to modern birds has placed them at the center of paleontological research for the last several decades. Herein we describe a new species of dromaeosaurid—Kuru kulla, gen. et sp. nov.—based on a partial skeleton from the Late Cretaceous Khulsan locality (Barun Goyot Formation) of Mongolia. This species is diagnosed by several autapomorphies within Dromaeosauridae, including a sharp groove anterior and ventral to the narial fossa on the premaxilla, a posterolaterally directed hornlet on the posterodorsal process of the lacrimal, a deep surangular bearing two surangular foramina, and anteriorly displaced pleurocoels on the dorsal centra. The taxon is further characterized by a unique combination of characters, including a mediolaterally narrow metatarsal II, serrations on both carinae of the dentary teeth, hyposphenes that are widely separated but joined by a web of bone, and a lacrimal with a poorly developed boss on its lateral surface. Phylogenetic analysis finds Kuru kulla to be the sister taxon of Adasaurus mongoliensis, from the slightly later Nemegt Formation, with which it is united by three synapomorphies: a posterior surangular foramen that is ∼30% the depth of the surangular, absence of a fourth trochanter of the femur, and thoracic centra that are markedly longer than their midpoint widths. The recognition of this taxon has important implications for common assumptions of Mesozoic terrestrial ecosystem structure and adds new data to a recently recognized pattern in dromaeosaurid faunal composition among Late Cretaceous localities in Mongolia and Inner Mongolia (Nei Mongol Autonomous Region, China).
Dinosauria Owen, 1843 Theropoda Marsh, 1881 Coelurosauria Huene, 1920 Maniraptora Gauthier, 1986 Dromaeosauridae Matthew and Brown, 1922 Kuru kulla, gen. et sp. nov Etymology: Kurukullā (fig. 1) is a deity venerated in Tibetan Buddhism. Considered peaceful to semiwrathful, she is usually depicted with four arms, holding in one pair of hands a bow and arrow, and in the other pair a hook and noose, all of which are made of flowers. Kurukullā is particularly associated with major life transitions. We emphasize here that the generic name Kuru is not in reference to the cannibalism-borne prion disease of the same name. SUMMARY: Kuru kulla is a new species of velociraptorine dromaeosaurid from the Barun Goyot Formation at Khulsan. It is the first velociraptorine to be recognized from a locality and stratum that has previously yielded a different velociraptorine species, in this case, the recently described Shri devi (Turner et al., 2021). As such, it provides important insight into the structure of Late Cretaceous nonavian dinosaur-bearing faunas. Kuru kulla demonstrates that similar, closely related dinosaur species could and did coexist, contrary to general expectations that such species would not tolerate each other due to competitive exclusion (Molnar, 1990). This has ramifications for the taxonomic referral of new fossil material and argues strongly for an apomorphy-based (rather than similarity- and provenance-based) approach to referral. James G. Napoli, Alexander A. Ruebenstahl, Bhart-Anjan S. Bhullar, Alan H. Turner and Mark A. Norell. 2021. A New Dromaeosaurid (Dinosauria: Coelurosauria) from Khulsan, Central Mongolia. American Museum Novitates. (3982); 1-47. DOI: 10.1206/3982.1  |
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