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Thursday, February 7th, 2019
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| 4:44a | [Mollusca • 2018] Microparmarion exquadratus • Bringing the Lab to the Field: A New Lowland Microparmarion Semi-slug (Gastropoda: Ariophantidae) from Borneo, described and DNA-barcoded in the Forest
Abstract Cybertaxonomy and portable DNA sequencing now make it possible for citizen scientists to be engaged in the discovery and description of new taxa. We here provide a proof of principle. A new semi-slug, Microparmarion exquadratus n. sp. (Ariophantidae) was discovered during a field course in tropical biology in Borneo for citizen scientists. The new species is the first lowland representative of its genus. It differs from other (high-elevation) Microparmarion species by its size, pigmentation on head and tail, and shape of dart sac and receptaculum. As part of the course programme, the participants prepared a taxonomic description and illustrations, and used the mobile genomic laboratory of the course to obtain DNA barcodes. As far as we are aware, this is the first time a new invertebrate species has been described both morphologically and genetically from the field.
Microparmarion exquadratus Schilthuizen et al., new species Etymology: The name was chosen at a naming and voting session during the taxon expedition and refers to the ‘squad’ of participants that jointly sampled this species during night-time walks in the forest. The taxonomic authority for this species is attributed to all authors of this paper. Following Article 51 C of the Code (ICZN, 1999), the species can be referred to as Microparmarion exquadratus Schilthuizen et al., 2018, provided the full citation of this publication appears in the bibliography or elsewhere in the referring work. Diagnosis: Among Microparmarion species of Borneo, M. exquadratus is characterized by small size (less than half the size of M. pollonerai and M. simrothi), three dark longitudinal stripes on head (shared with M. simrothi, but lacking in M. pollonerai and M. litteratus), dark dorsal stripe on tail, kink in dart sac (shared with M. pollonerai) and reduced receptaculum. Remarks: In colour pattern, M. exquadratus is somewhat similar to a Microparmarion species found at an elevation of 1,200 m asl in Long Pa Sia, southwestern Sabah, and also to a species photographed (but not collected) at 1,000 m asl in Penrissen, Sarawak (Schilthuizen, 2017). However, it is unlikely to be conspecific with either, because it differs in colour pattern (the Penrissen specimen has two, rather than three, head stripes, and the Long Pa Sia specimen lacks the black markings on the mantle lobes) and is larger in size. For the time being, therefore, we consider the M. exquadratus to be restricted to Tawau Hills Park. Our phylogenetic reconstruction (Fig. 5), although primarily intended to assess the genetic distinctness of the new species, also suggests that the genus Microparmarion consists of multiple clades that are not fully congruent with named species. We therefore recommend that the genus be subjected to a formal revision. We must also stress that our work was conducted under several limitations and constraints. It was part of a full 10-day field course schedule, carried out by untrained citizen scientists in a field station with limited equipment and erratic electricity supply. Specimens could not be exported. Consequently, the extent of our work is less than is customary for descriptions of new semi-slug species: we sequenced only three individuals and dissected only one. Also, all individuals were obtained from a very small geographic area. Nonetheless, the genetic and morphological features are sufficient to recognize the species unambiguously.  Menno Schilthuizen, Anna Pazos Clavera, Min Sheng Khoo, Carin A. Bondar, Charles H. S. Elder, Aglaia M. Bouma, Taly D. Eddington, Christian Reisinger, Emanuela Cosentino, Marzia Rossato and Massimo Delledonne. 2018. Bringing the Lab to the Field: A New Lowland Microparmarion Semi-slug (Gastropoda: Ariophantidae) described and DNA-barcoded in the forest. Journal of Molluscan Studies. eyy052. DOI: 10.1093/mollus/eyy052  | ||||||
| 10:38a | [Ichthyology • 2018] Channa torsaensis • A New Ornamental Species of Snakehead Fish (Teleostei: Channidae) from River Torsa of West Bengal, India
ABSTRACT A new Channa species described from River Torsa of Brahmaputra river basin, West Bengal, India. Channa torsaensis sp. nov. a new species of Channa, is distinguished from congeners by a combination of the following characters namely a dorsal, anal and caudal fins being bluish with a broad dark blue border having a tinge of orange border covering the dark blue border; dorsal fin with numerous back spots; caudal fin with 9-10 black bands; 5-6 oblique greyish-blue bands present on the body; lateral line pored scales 46 in number; dorsal fin rays 36-38; anal fin rays 22 - 25; total vertebrae 44- 45 (16+28). Key words: Taxonomy, Endemic, Brahmaputra basin, new species of Channa.  Channa torsaensis sp. nov. New English name: Cobalt Blue Channa Local name (Bengali): Neel Chang Diagnosis. Channa torsaensis sp. nov. is distinguished from all other species of Channa except C. pomanensis and C. quinquefasciataby an unique broad dark blue border on the dorsal, anal and caudal fin and having a tinge of orange border covering; 5-6 oblique greyish-blue bands present on the body. ....
Distribution and Habitat At present, known to be distributed from tributary of River Torsa, Dakshin Barajhar forest, Alipurduar district, West Bengal, India (Fig.4). The running river water was transparent, cool, low depth and having various substrata like gravel, pebbles, sand, soil and medium to large boulders. Etymology. The new species is named after the River Torsa, from where the fish was collected. CONCLUSION: Based on the diagnosis, Channa species have been classified into 15 groups from North-East India in the Brahmaputra drainage, India. Channa torsaensis sp. nov. brings the number of Channa species to 16 from in Brahmaputra drainage, North East India. Channa torsaensis is male mouth-brooder and more aggressive in nature than other native Channa species. Arpita Dey, Ruksa Nur, Basudhara Raychowdhury, Debapriya Sarkar, Laishram Kosygin Singh and Sudip Barat. 2018. A New Ornamental Species of Snakehead Fish (Teleostei: Channidae) from River Torsa of West Bengal, India. International Journal of Pure & Applied Bioscience (Int. J. Pure App. Biosci. - IJPAB). 6(6); 497-503. DOI: 10.18782/2320-7051.7131 | ||||||
| 10:55a | [Paleontology • 2019] Gobiraptor minutus • A New Baby Oviraptorid Dinosaur (Dinosauria: Theropoda) from the Upper Cretaceous Nemegt Formation of Mongolia
Abstract Recent discoveries of new oviraptorosaurs revealed their high diversity from the Cretaceous Period in Asia and North America. Particularly, at the family level, oviraptorids are among the most diverse theropod dinosaurs in the Late Cretaceous of Mongolia and China. A new oviraptorid dinosaur Gobiraptor minutus gen. et sp. nov. from the Upper Cretaceous Nemegt Formation is described here based on a single holotype specimen that includes incomplete cranial and postcranial elements. The most prominent characters of Gobiraptor are its thickened rostrodorsal end of the mandibular symphysis and a rudimentary lingual shelf on each side of the dentary. Each lingual shelf is lined with small occlusal foramina and demarcated by a weakly developed lingual ridge. This mandibular morphology of Gobiraptor is unique among oviraptorids and likely to be linked to a specialized diet that probably included hard materials, such as seeds or bivalves. The osteohistology of the femur of the holotype specimen indicates that the individual was fairly young at the time of its death. Phylogenetic analysis recovers Gobiraptor as a derived oviraptorid close to three taxa from the Ganzhou region in southern China, but rather distantly related to other Nemegt oviraptorids which, as the results of recent studies, are also not closely related to each other. Gobiraptor increases diversity of oviraptorids in the Nemegt Formation and its presence confirms the successful adaptation of oviraptorids to a mesic environment.
Systematic paleontology Dinosauria Owen, 1842 Theropoda Marsh, 1881 Maniraptora Gauthier, 1986 Oviraptorosauria Barsbold, 1976 Oviraptoridae Barsbold, 1976 Gobiraptor minutus gen. et sp. nov. Etymology: The generic name Gobiraptor is a combination of ‘Gobi’ which refers to the Gobi Desert where the holotype specimen was found and ‘raptor’ which is Latin for thief. The specific name ‘minutus’ is Latin for small and refers to the small size of the holotype specimen. Holotype: The holotype specimen (MPC-D 102/111) (Figs 2–4, S2 and S3 Figs) consists of mostly incomplete cranial and postcranial elements including ventral parts of the premaxillae and maxillae, a tip of the right jugal, fused vomer, parts of articulated pterygoids and ectopterygoids, incomplete right palatine, central part of the left postorbital, partial right quadrate and quadratojugal, incomplete lower jaw, with most of its elements broken, the last sacral vertebra which is articulated with the two proximalmost caudal vertebrae, articulated but incomplete proximal caudal vertebrae, fragments of chevrons, partial right scapula and humerus, incomplete pelvic girdles, nearly complete both femora, complete left metatarsus with distal tarsals 3 and 4, incomplete left pedal digits I, III, and IV, and several unidentified fragments. MPC-D 102/111 was also found with other theropod skeletons including postcranial elements of alvarezsaurids and larger oviraptorids. Type locality and horizon: Altan Uul III, Ömnögovi Province, Mongolia (Fig 1, S1 Fig). Upper Cretaceous Nemegt Formation. Diagnosis: Gobiraptor minutus is an oviraptorid dinosaur diagnosed by the following unique set of characteristics (autapomorphies are marked with an asterisk): a flat articular surface for the quadratojugal on the quadrate*; rostrocaudally elongate dentary rostral to the external mandibular fenestra; extremely thickened rostrodorsal end of the mandibular symphysis with a caudal expansion of its dorsal surface *; a rudimentary lingual triturating shelf on each dentary bearing small occlusal foramina*; a weakly developed lingual ridge on each lingual shelf*; absence of any prominent symphyseal ventral process of the dentary; coronoid bone present; the rostral end of the coronoid bone wedging into the ventral surface of the dorsal ramus of the dentary*; cranial trochanter of the femur separated from the greater trochanter with a distinct furrow between them. ....  Conclusions: Gobiraptor minutus gen. et sp. nov. is a new derived oviraptorid represented by an incomplete skeleton including both cranial and postcranial elements. Gobiraptor is primarily distinguished from other oviraptorids by its dentary with the extremely thickened rostrodorsal end of the mandibular symphysis, lingual ridges and lingual shelves bearing occlusal foramina. The unique morphology of the mandible of Gobiraptor is probably closely related to a crushing-related feeding style and a specialized diet, which may have incorporated hard seeds or shelled organisms. Although Gobiraptor was recovered from the Nemegt Formation, its phylogenetic position showed a close relationship with three Ganzhou oviraptorids. The distant relationships among the Nemegt oviraptorids on the phylogenetic tree were reaffirmed in this study. Therefore, it is highly unlikely that the evolution of these unusually diverse animals was facilitated by a simple sympatric speciation. The presence of Gobiraptor in the Nemegt Formation, together with occurrences of other oviraptorids, also indicates that abundant oviraptorids lived in mesic environments and they were one of the most diverse and successful groups of dinosaurs in the Nemegt region.    Sungjin Lee, Yuong-Nam Lee , Anusuya Chinsamy, Junchang Lü†, Rinchen Barsbold and Khishigjav Tsogtbaatar. 2019. A New Baby Oviraptorid Dinosaur (Dinosauria: Theropoda) from the Upper Cretaceous Nemegt Formation of Mongolia. PLoS ONE. 14(2): e0210867. DOI: 10.1371/journal.pone.0210867 New oviraptorosaur species discovered in Mongolia phys.org/news/2019-02-oviraptorosaur-spe   |
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