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Thursday, February 17th, 2022
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| 3:32a | [Paleontology • 2022] Iberospinus natarioi • A New Theropod Dinosaur (Theropoda: Spinosauridae) from the early Cretaceous (Barremian) of Cabo Espichel, Portugal: Implications for Spinosaurid Evolution
Abstract Spinosaurids are some of the most enigmatic Mesozoic theropod dinosaurs due to their unique adaptations to aquatic environments and their relative scarcity. Their taxonomy has proven to be especially problematic. Recent discoveries from Western Europe in general, specifically Iberia, provide some of the best specimens for the understanding of their phylogeny, leading to the description of the spinosaurid Vallibonavenatrix cani and the recognition of the Iberian dinosaur Camarillasaurus cirugedae as one of them. Portuguese associated spinosaurid remains (ML1190) from the Papo Seco Formation (early Barremian) were previously assigned to Baryonyx walkeri but new material recovered in 2020 along with new phylogenetic analyses suggests a different phylogenetic placement, making their revision necessary. Here we show that these remains are not attributable to Baryonyx walkeri, but to a new genus and species, Iberospinus natarioi, gen. et sp. nov. The new taxon is characterized by the presence of a single Meckelian foramen in the Meckelian sulcus, a straight profile of the ventral surface of the dentary and a distal thickening of the acromion process of the pubis between other characters. Iberospinus natarioi is recovered as a sister taxon of the clade formed by Baryonyx and Suchomimus, and outside Spinosaurinae when Vallibonaventrix cani is excluded from the analysis. The description of this taxon reinforces Iberia as a hotspot for spinosaur biodiversity, with several endemic taxa for the region. As expected for the clade, the dentary displays a highly vascularized neurovascular network. The morphometric analysis of parts of the skeleton (pedal phalanx and caudal vertebrae, among others) shows an intermediate condition between basal tetanurans and spinosaurines.
Dinosauria Owen, 1842 Theropoda Marsh, 1881 Megalosauroidea (Fitzinger, 1843) Spinosauridae Stromer, 1915 Iberospinus n. gen. Etymology: Ibero- derived from the Roman name for the Iberian Peninsula; and -spinus, latin for “spine”, because the length of the neural spines is one of the main features that defined the clade to which this animal belongs to. Iberospinus natarioi sp. nov. Etymology: Dedicated to Carlos Natário, who discovered the holotype. Holotype: ML 1190, many bones from same individual (Table 1).Type locality and horizon: Praia de Aguncheiras (Also known as Praia do Guincho), in the municipality of Sesimbra, Setúbal district, Portugal (38.4° N, 9.2° W; paleocoordinates: 31.8° N, 1.3° E). The sediments that contain the fossil belong to the Papo Seco Formation, dated to Early Barremian. Diagnosis: Medium sized spinosaurid theropod with the following autapomorphies: 1) dentary with a single foramen in the Meckelian sulcus, 2) dentary´s ventral edge is straight (not upturned), 3) presence of laminae in the pleurocelic depression of the medio-distal caudal vertebrae, 4) scapula, anterior rim is straight (acromion not protruding), 5) scapula with reduced acromial ridge, 6) scapula, contact with coracoid occupies the entire ventral surface, 7) pubic apron thick in almost the entire length of the pubis shaft, 8) mound like eminence in the proximal lateral part of the pubis.   Conclusions: The revision of Barremian spinosaurid material previously assigned to Baryonyx along with newly recovered material from the site has led to the description of a new genus and species of Iberian spinosaurid, Iberospinus natarioi, from the Papo Seco Formation of Cabo Espichel, Sesimbra, Portugal. The specimen includes: dentary, isolated teeth, scapula, ribs, a dorsal vertebra, neural arches, pubic shaft, 15 caudal vertebrae, calcanea, and one pedal ungual (Fig 32). It is a medium sized spinosaurid diagnosable by: the dentary with only one foramen in the Meckelian sulcus and a straight ventral edge (not upturned), the presence of laminae in the pleurocelic depression of the medio-distal caudal vertebrae, the straight anterior rim of the scapula (acromion not protruding); the reduced acromial ridge of the scapula and the contact with coracoid occupying the entire ventral surface of it; the pubic apron being thick in almost the entire length of the pubis shaft, and the presence of a mound-like eminence in the proximal lateral part of the pubis. Phylogenetic analysis recovers Iberospinus natarioi outside of the clade formed by Suchomimus and Baryonyx, although other characters (like the teeth denticles) point towards an affinity with baryonychines. The morphometric analysis of several anatomical elements points towards an ecology similar to the expected for a basally branching spinosaurid. The addition of yet another taxon to the diversity of spinosaurids in Iberia besides Vallibonavenatrix, Baryonyx, and Camarillasaurus indicates that the clade possibly originated in Western Europe. Octávio Mateus and Darío Estraviz-López. 2022. A New Theropod Dinosaur from the early Cretaceous (Barremian) of Cabo Espichel, Portugal: Implications for Spinosaurid Evolution. PLoS ONE. 17(2): e0262614. DOI: 10.1371/journal.pone.0262614  | ||||||||
| 2:09p | [Botany • 2022] Monoon roseum, M. ornithocephalum, etc. (Annonaceae) • Distinctive New Monoon Species from Thailand, increasing Diversity of A Genus of Ecologically Important Asian Trees
Abstract The widespread Asian genus Monoon (Annonaceae) comprises about 70 tropical forest species, over 20 of which occur in Thailand. Four new species from Thailand are described here: Monoon roseum and M. ornithocephalum from Peninsular Thailand and M. phukraduengense and M. phuluangense from North-Eastern Thailand. Keywords: New species, Peninsular Thailand, North-Eastern Thailand, Polyalthia
Monoon ornithocephalum Bunchalee, sp. nov. Monoon ornithocephalum resembles M. fuscum, differing in the absence of an inflorescence peduncle, the oblanceolate petals, and the asymmetrically oblongoid or ellipsoid monocarps 15–20 mm wide with stipes 15–18 mm long (Table 1). In contrast, M. fuscum has inflorescence peduncles 2–4 mm long, oblong petals, and symmetrically ovoid monocarps 10–12 mm wide with stipes 3–5 mm long. Thailand.— SOUTH-WESTERN: Prachuap Khiri Khan [Kui Buri National Park]; PENINSULAR: Surat Thani [Khlong Phanom National Park]. Ecology.— Tropical rainforest, 100–700 m. Etymology.— Monoon ornithocephalum is named for the shape of the monocarp, which resembles a bird’s head. Vernacular.— Nang na huai nok (หนังหนาหัวนก).
Monoon phukraduengense Bunchalee, sp. nov. Monoon phukraduengense resembles M. laui (Merr.) B.Xue & R.M.K.Saunders in texture and size of leaves and flower parts when dried, number of secondary veins, and the thickness of pedicels, but differs in its asymmetrical elliptic to oblanceolate leaves, cuneate to broadly cuneate leaf bases, oblong petals 35–40 × 7–9 mm, and flower pedicels 25–30 × 1.8–2 mm (Table 2). It is also similar to M. phuluang-ense but is distinguished from that species by the inflorescences only 1–4-flowered, glabrous pedicels 25–30 mm long, valvate sepals, petals green to yellowish green and tinged with purplish red on the inner base, and carpels 1–1.2 mm long. Thailand.— NORTH-EASTERN: Loei [Phu Suan Sai National Park; Phu Kradueng National Park]. Ecology.— Hill evergreen forest or semi-evergreen forest, 700–1,222 m. Etymology.— The specific epithet refers to the type locality. Vernacular.— Saban nga phukradueng (สะบันงาภูกระดึง). Monoon phuluangense Bunchalee, sp. nov. Monoon phuluangense differs from both M. laui and M. phukraduengense in having longer pedicels ((30–)35–50(–60) mm), elliptic-oblong to oblong outer petals (29–)35–43 × 8–10 mm, and inner petals that are elliptic or curved on one side and 40–45 × 10–12 mm (Table 2). Monoon phuluangense further differs from M. phukraduengense in having inflorescences with up to 10 flowers, pubescent pedicels, glabrous sepals, petals yellow to reddish yellow with conspicuous red veins, and carpels 1.5–1.8 mm long. Thailand.— NORTH-EASTERN: Loei [Phu Luang Wildlife Sanctuary]. Ecology.— Hill evergreen forest with oak trees, in sandy soil, 1,000–1,400 m. Etymology.— The specific epithet refers to the type locality. Vernacular.— Saban nga phuluang (สะบันงาภูหลวง). Notes.— Monoon phuluangense and M. phukraduengense, both species of higher-elevation habitats in North-Eastern Thailand, are compared, along with M. laui, in Table 2. Monoon phuluangense also somewhat resembles M. roseum, but the petals of M. phuluangense are yellow with red markings and are not attenuate at the base.
Monoon roseum Bunchalee, sp. nov. Monoon roseum resembles M. hookerianum (King) B.Xue & R.M.K.Saunders and M. glabrum (King) B.Xue & R.M.K.Saunders but differs from both species in the fasciculate inflorescence, pale pink to red ovate petals, and monocarp stipes 40–55 mm long, versus pedunculate monochasial cymes, yellow oblong, oblanceolate, or obovate petals, and monocarp stipes 25–40 mm long. Thailand.— PENINSULAR: Ranong; Surat Thani; Nakhon Si Thammarat [Ban Kiriwong; Khao Luang National Park]; Trang [Khao Chetyot]. Ecology.— Tropical rainforest, 150–660(–1,200) m. Etymology.— The specific epithet refers to the pale pink to red colour of the flowers, unusual in the genus. Vernacular.— Ka nan (กานัน) (Phangnga).  SUMMARY: The new Monoon species described here are the only species of the genus known to be endemic to Thailand. Monoon phukraduengense and M. phuluangense occur in a small area of the North-Eastern Region. The other native Monoon species known from this Region, M. obtusum, M. simiarum and M. viride (Craib) B.Xue & R.M.K.Saunders, are more common and widely distributed. In the Peninsular Region, M. ornithocephalum and M. roseum bring the total number of described native species for the Region to 14 and the Monoon diversity for Thailand to 20 described native species. Pasakorn Bunchalee, David M. Johnson and Nancy A. Murray. 2022. Distinctive New Monoon Species (Annonaceae) from Thailand, increasing Diversity of A Genus of Ecologically Important Asian Trees. Thai Forest Bulletin (Botany). 50(1); ; 9–19. DOI: 10.20531/tfb.2022.50.1.02 | ||||||||
| 3:31p | [Ichthyology • 2022] The Real Devario browni from the Irrawaddy River Basin, and the new Devario ahlanderi (Teleostei: Cyprinidae: Danioninae) from the Salween River Basin in Myanmar
Abstract Specimens of Devario from a tributary to the Salween River in Myanmar initially identified as Devario browni but with a different colour pattern, were subjected to a comparative morphological analysis with syntypes and other specimens of D. browni from near its putative type locality. The Salween sample was recognised as representing a distinct species, here named Devario ahlanderi. No significant morphometric differences were found between D. ahlanderi and D. browni. The type series of Devario ahlanderi differed from D. browni and most other species of Devario in the presence of 14 vs 12 circumpeduncular scale rows. Devario ahlanderi, D. browni, and D. fangae shared subadult colour pattern. Adult D. ahlanderi differed from adult D. browni in the trunk colour pattern, consisting of rows of dark blotches or short vertical bars. In D. browni, the flank colour pattern consisted of horizontal dark stripes, the middle of which (the P stripe) frequently diverged anteriorly, enclosing a small light blotch. Specimens previously reported as D. browni from the upper Salween River basin in Yunnan differed slightly in colour pattern, and may represent a distinct species. Devario ahlanderi shared spotted colour pattern with that of one ontogenetic state in D. kysonensis, except that a row of spots marking the P-1 stripe in D. kysonensis was absent in D. ahlanderi. The minimum genetic distance between D. ahlanderi and congeneric species varied from 2.1 to 5% in the mt-coI gene. Key words: colour pattern, freshwater, morphology, South Asia, species discrimination, taxonomy Devario browni (Regan, 1907) Revised definition. Distinguished from all other species of Devario by the shape of the P stripe: gradually ex-panding posteroanteriorly, either forming a uniform brown blotch anteriorly, or P stripe diverging anteriorly, forming a brown blotch enclosing a small light spot or two contiguous small light spots. Geographical distribution and habitat. The type locality of Devario browni is not known, but was probably near Lashio in the upper Irrawaddy River basin. Specimens from streams near Lashio were identified as D. browni (Appendix 1). Presence of D. browni in the upper Salween River basin in Yunnan was not confirmed. Devario shanensis was syntopic with D. browni near Lashio (Appendix 1).Other syntopic fish species were identified as Opsarius barnoides, Pethia stoliczkana, and Danio roseus.
Devario ahlanderi, new species Definition. Distinguished from all other species of Devario by the modification in adults of the anterior half of the P stripe into a series of short irregular bars or spots. Explanation of the specific name: The specific name is a noun in the genitive case. The species is dedicated to Erik Åhlander, long time Senior Assistant in the ichthtyology and herpetology collection of the Swedish Museum of Natural History, and a key person in the successful development and operation of ichthyology at the NRM. Sven Kullander and Michael Norén. 2022. The Real Devario browni from the Irrawaddy River basin, and the new Devario ahlanderi from the Salween River basin in Myanmar (Teleostei: Cyprinidae: Danioninae). Zootaxa. 5100(1); 54-72. DOI: 10.11646/zootaxa.5100.1.2 | ||||||||
| 4:09p | [Botany • 2022] Silene vanchingshanensis (Caryophyllaceae) • A New Species from Guizhou, southwest China
Abstract Silene vanchingshanensis (Caryophyllaceae), a new species from Fanjingshan Mountain in Guizhou (southwest China) is described and illustrated. It is morphologically similar to S. morrisonmontana and S. hupehensis, from which it can be easily distinguished by having pubescent stems usually 10–15 cm long, linear-oblanceolate leaves 3–6 cm × 3–6 mm, often 2–5-flowered cymes, pink or violet petals and narrowly ovoid capsules. Keywords: Endemism, Guizhou, Silene, Silene morrisonmontana, Silene hupehensis
 Silene vanchingshanensis C.Y.Wu ex Huan C. Wang & Feng Yang, sp. nov. Diagnosis: Silene vanchingshanensis is similar to S. morrisonmontana, from which it differs by its shape and size of leaves (linear-oblanceolate, 3–6 cm × 3–6 mm vs. linear, 2–7 cm × 2–3 mm), cymes (often 2–5-flowered vs. usually solitary) and colour of petals (pink or violet vs. white). Etymology: The specific epithet vanchingshanensis is derived from the type locality “Vanchingshan”, a variant name for Fanjingshan Mountain. Distribution and habitat: Silene vanchingshanensis is currently known only from locus classicus (Fanjingshan Mountain), a famous scenic resort in Guizhou, southwest China. The species grows on cliffs or rock crevices of the mountain summit at elevations of 2,100–2,500 m. Feng Yang, Jin-Li Liu, Ping-Ping Li and Huan-Chong Wang. 2022. Silene vanchingshanensis (Caryophyllaceae) A New Species from Southwest China. PhytoKeys. 189: 155-162. DOI: 10.3897/phytokeys.189.79631 |
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