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Thursday, March 14th, 2019
| Time | Event | ||||||||||
| 2:09a | [Paleontology • 2019] Convolosaurus marri • A New Basal Ornithopod (Dinosauria: Ornithischia) from the Early Cretaceous of Texas, USA
Abstract Material from a minimum of twenty-nine individuals of a new ornithopod, represented by nearly every skeletal element, was recovered from the Proctor Lake locality in the Twin Mountains Formation (Aptian) of north-central Texas. This material includes various ontogenetic stages, providing insight into the growth patterns of this species. The new ornithopod, Convolosaurus marri gen. et sp. nov., is recovered outside of Iguanodontia, but forms a clade with Iguanodontia exclusive of Hypsilophodon foxii. The presence and morphology of four premaxillary teeth along with a combination of both basal and derived characters distinguish this taxon from all other ornithopods. Basal characters present in C. marri including the presence of premaxillary teeth, the shape of the dentary teeth, and position of the pterygoid wing on the quadrate, whereas the presence of opisthocoelous cervical vertebrae, large proximal caudal neural spines, and curved maxillary tooth roots suggest C. marri is more derived than 80% of the basal neornithischians included in this analysis. 
DINOSAURIA Owen, 1842 ORNITHISCHIA Seeley, 1887 NEORNITHISCHIA Cooper, 1985 CERAPODA Sereno, 1986 ORNITHOPODA Marsh, 1881 Convolosaurus marri gen. et sp. nov. Holotype: SMU 72834, a skull and partial articulated skeleton with 9 cervical vertebrae; 15 dorsal vertebrae; 6 sacral vertebrae; 23 caudal vertebrae; right and partial left scapula; right and partial left coracoids; left and partial right humeri; left ulna; left radius; partial left manus; articulated pelvis including the left and right ilia, proximal left and right ischia, partial prepubic rods; proximal and distal ends of the left and right femora and the mid-part of the left shaft; proximal left and right tibiae; and proximal left fibula. The type specimen, SMU 72834, is the largest individual in the sample measuring approximately 2.5–3 m in length; however, this skeleton does not represent a full grown adult, thus the adult size of this species in unknown. Diagnosis: The presence of four premaxillary teeth with proximodistally oriented sulcus on the buccal surface distinguishes Convolosaurus marri gen. et sp. nov. from all other ornithopods. Further, it can be distinguished from other basal ornithopods by a unique combination of primitive and derived character states. Primitive character states include the presence of premaxillary teeth and two supraorbitals that extend across the entire orbit. Derived character states include: curved maxillary tooth roots; opisthocoelous cervical vertebrae; sacral neural spines twice the height of the sacral centra; proximal caudal neural spines 1.5 times the height of the centrum; expanded ischial ‘foot’; shallow intercondylar groove on the anterior surface of the femur; and a laterally compressed prepubic process. Etymology: The generic name Convolosaurus translates from Latin meaning “flocking lizard” referring to clusters of juvenile specimens. The species name marri is in honor of Dr. Ray H. Marr who produced the Society of Vertebrate Paleontology videos “We are SVP” and “About the SVP Logo” posted on the SVP website (vertpaleo.org), and who is a strong proponent of students at Southern Methodist University (SMU).
  Conclusions: The Proctor Lake fossil locality contains a wealth of specimens providing not only nearly complete individual skeletons, but also insight into ontogeny and population structure. The femoral length distribution of 29 individuals from the Proctor Lake locality indicates a high mortality rate among the smallest and presumably youngest individuals. Clusters of individuals of varying sizes suggest individuals flocked together long after hatching perhaps for protection against predators. The specimens recovered from Proctor Lake reveal a new species of basal ornithopod with a unique set of both basal and derived characters. Characters including an expanded ischial foot, curved maxillary tooth roots, and opisthocoelus cervical vertebrae position Convolosaurus marri in a clade exclusive of most basal ornithischians including Hypsilophodon foxii [Galton, 1974], but characters such as the presence of premaxillary teeth, shape of the frontals, and the position of the pterygoid wing on the quadrate position C. marri outside of Iguanodontia. Thus, this new species provides crucial information on the evolution of basal neornithischians. Kate A. Andrzejewski, Dale A. Winkler and Louis L. Jacobs. 2019. A New Basal Ornithopod (Dinosauria: Ornithischia) from the Early Cretaceous of Texas. PLoS ONE 14(3): e0207935. DOI: 10.1371/journal.pone.0207935 | ||||||||||
| 2:33p | [Botany • 2019] Manglietia pubipedunculata (Magnoliaceae) • A New Species from Yunnan, China
Abstract A new species, Manglietia pubipedunculata Q. W. Zeng & X. M. Hu (Magnoliaceae) is described and illustrated from Yunnan, China. In addition to macromorphological examination, we comparatively studied on micromorphology of leaf epidermis, leaf structure, and epidermal cell on the sclerotesta. This new species is similar to M. kwangtungensis in terms of having dense pubescence, however, their pubescence are quite different. Manglietia pubipedunculata has appressed, compressed, shorter and sparser pubescence consisting of single or two cells. Moreover, it differs from M. kwangtungensis by showing shorter and thicker peduncles, longer styles, basal carpels covered with sparsely brown appressed pubescence, and more ovules per carpel. Furthermore, the new species has thinner leaves, brown and rugged surfaces on sclerotesta, and the alveolate cell pattern consisting of pentagon or hexagon cells with papilla on secondary cell wall under the observation by SEM. The phylogenetic analysis from two nuclear PHYA and LEAFY and chloroplast trnH-psbA sequences of 11 taxa reveals that M. pubipedunculata is a distinct species.
  Manglietia pubipedunculata Q. W. Zeng & X. M. Hu, sp. nov. Type. CHINA. Yunnan Province, Wenshan Prefecture, Maguan County, Miechang Town, Daxinzhai Village, ..., evergreen broad-leaved forests, alt. 1453 m, ..., 14 May 2004, Q. W. Zeng 89 (holotype: IBSC). The same locality, 9 September 2003, Q. W. Zeng 80 (paratype: IBSC). Diagnosis: Species M. kwangtungensis affinis, a qua ramulis, gemmis, petiolis, foliis subtus pedunculisque dense appresse brunneo-pubescentibus, veins reticulatis inconspicuis, tepalis 10−11, 3 exterioribus 8.8−9.8 cm longis et 3.8−4.8 cm latis, carpellis 39, basi sparse appresse pubescentibus, stylis 7−8 mm, pedunculis gracilibus 5.5−7.5 cm longis et 7−8 mm latis, folliculorum rostris 3–5 mm longis differt. Distribution and habitat: Manglietia pubipedunculata is so far known only from a single location in Maguan County, the southeast of Yunnan Province. It grows in evergreen broad-leaved forests at 1400−1600 m with M. megaphylla, M. ovoidea and Alnus nepalensis, etc.   Xiao-Min Hu, Qing-Wen Zeng, Ya-Si Liu, Lin Fu, Ru-Chun Xi, Hong-Feng Chen and Xiao-Mei Deng. 2019. Manglietia pubipedunculata (Magnoliaceae), A New Species from Yunnan, China. PLoS ONE. 14(3): e0210254. DOI: 10.1371/journal.pone.0210254   | ||||||||||
| 2:35p | [Chilopoda • 2019] Arrup akiyoshiensis • A New Species of the Genus Arrup (Geophilomorpha, Mecistocephalidae) from A Limestone Cave in Akiyoshi-dai, Western Japan
Abstract Arrup akiyoshiensis Tsukamoto & Shimano, sp. n. is described from a limestone cave, Kagekiyo-ana, in Akiyoshi-dai, one of the largest karst regions in Japan, Yamaguchi prefecture. It is distinguishable from 14 valid named congeners by some unique characteristics including entire areolation on the cephalic pleurite, elongation of distal part of female gonopod, and a tubercle on forcipular segment II. In addition, the 18S rRNA gene sequences of A. akiyoshiensis Tsukamoto & Shimano, sp. n. and A. ishiianus, one of the most morphologically similar species, differed by four bp out of 1821 bp. The fact that only troglobionts and troglophilic species are found in the collection site suggests that this new species might be a cave-dweller. Keywords: Arrupinae, Chilopoda, Kagekiyo-ana, limestone, taxonomy, 18S rRNA gene
Taxonomy Family Mecistocephalidae Bollmann, 1893 Genus Arrup Chamberlin, 1912 Arrup akiyoshiensis Tsukamoto & Shimano, sp. n. Japanese name: Kagekiyo-tsumejimukade Diagnosis: Arrup akiyoshiensis sp. n. can be distinguished from the all named congeners by a combination of the following morphological characteristics: frontal line curved; seven pectinate lamellae in mandible; comma-shaped distal lobe of coxal projection in first maxillae; a tiny tubercle on outer-distal corner of each article of the telopodite; distal article of the telopodite of the second maxillae without claw; the well-developed tooth of forcipular article I; the triangular basal tooth in tarsungulum; the poison calyx overreaching forcipular article I; 31–35 pores on lateral and ventral sides on coxopleura. .... Etymology: The species name is derived from the name of Akiyoshi-dai Karst region, which includes the type locality. Distribution: Known from only the type locality. Type locality: Kagekiyo-ana, Mitou Town (Mitou-cho), Mine City (Mine-shi), Yamaguchi Prefecture, Japan. Remarks: Arrup akiyoshiensis sp. n. is morphologically similar to several other congeners, especially A. holstii (Pocock, 1895) and A. ishiianus Uliana, Bonato & Minelli, 2007 (Fig. 10), but can be easily distinguished from them by a combination of the characteristics shown in Table 7. Sho Tsukamoto, Satoshi Shimano, Takashi Murakami, Shimpei F. Hiruta, Takeshi Yamasaki and Katsuyuki Eguchi. 2019. A New Species of the Genus Arrup from A Limestone Cave in Akiyoshi-dai, Western Japan (Chilopoda, Geophilomorpha, Mecistocephalidae). ZooKeys. 830: 33-51. DOI: 10.3897/zookeys.830.33060 |
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