Spore assemblages from the Lower Devonian Xujiachong Formation from Qujing,Yunnan, China

Abstract: The Lower Devonian Xujiachong Formation from the vicinity of Qujing City, Yunnan, China is interpreted as a terrestrial‐fluviatile‐lacustrine sequence. It contains important nonmarine biotas including plants, fish and invertebrates. The plants are particularly interesting as they include many endemic taxa. Dispersed spore assemblages have been recovered from the upper part of this formation. The spores are well preserved and of moderate thermal maturity. They are systematically described and four new species erected: Aneurospora xujiachongensis sp. nov., Chelinospora ouyangii sp. nov., Camptozonotriletes? luii sp. nov. and Leiozonospora xichongensis sp. nov. One new combination is proposed: Aneurospora conica (Ouyang and Lu) comb. nov. This is a rare report of a Lower Devonian dispersed spore assemblage from the South China Plate. Indeed, few dispersed spore assemblages of this age are known outside of Euramerica and Northern Gondwana. It is suggested that the Xujiachong Formation spore assemblages can all be equated to the polygonalis‐emsiensis Spore Assemblages Biozone (PE SAB) of Richardson and McGregor (1986) indicating an early (but not earliest) Pragian to ?earliest Emsian age. However, caution is urged, because biostratigraphical interpretation is difficult owing to distinct differences between dispersed spore assemblages from South China and Euramerica/Northern Gondwana. This almost certainly reflects palaeophytogeographical variation and regional endemism among early land plant floras on widely separated land masses. Palynofacies analysis supports a nonmarine origin for the deposits of the Xujiachong Formation, with the very rare marine palynomorphs that were encountered interpreted as reworked.     

A new species of vascular plants from the Xujiachong Formation (Lower Devonian) of Yunnan Province, China

A new species of early land vascular plants, Huia gracilis, is described from the Lower Devonian (Pragian-early Emsian) Xujiachong Formation, Qujing district, Yunnan Province, southwestern China. The plant possesses K- or H-type branching in the rhizome and a dichotomously branched erect system. An axillary tubercle is sometimes present at the branching position. Fertile axes terminate in loose spikes comprising terminal and lateral sporangia arranged helically. Sporangia with long stalks are ovate or elongate-ovate and reflex adaxially. The sporangium dehisces longitudinally in the radial plane of the fertile axis into two parts. The xylem is probably centrarch. Tracheids of G-type are characterised by annular secondary thickenings, between which is a sheet with irregular simple perforations. There may be some 'pores' in the enclosing wall of the perforation. H. gracilis differs from the type species H. recurvata mainly in the branching pattern, more slender morphology of the stem, sporangium and stalk. It is suggested that Huia may have originated from the primitive Cooksonia-like plants.     

A new microphyllous plant from the Lower Devonian of Yunnan Province, China

Sterile and fertile shoots of a microphyllous vascular plant are described from the Lower Devonian Posongchong Formation (? upper Siegenian), Yunnan Province, southern China and placed in the new taxon Halleophyton zhichangense gen. et sp. nov. The sterile axes are characterized by conspicuous, contiguous swollen rhomboidal to hexagonal leaf bases and relatively broad spatulate laminae. The relief of the leaf bases is not so pronounced in the fertile areas, which bear numerous cauline sporangia with two equal valves. In vegetative characters the new fossils, although smaller and more fragmentary, resemble Drepanophycus gaspianus but in the absence of information on the fertile parts of the latter and because of the controversy surrounding the concept of the genus Drepanophycus, we decided to erect a new genus. Its relationship to the lycophytes sensu stricto is equivocal as exact details of the relationship of sporangium with leaf and sporangium vascularization remain unknown.     

Emsian (Lower Devonian) conodonts from the Daliantang Formation at Daliantang,southeastern Yunnan,China

The lower/upper Emsian boundary witnessed prominent diversification of biostratigraphically important genera Polygnathus Hinde, Caudicriodus Bultynck, and Latericriodus Müller. In contrast, conodonts previously reported around this boundary from the South China Block were characterized by relatively low species or subspecies diversity, and only a few widely distributed and extensively studied zone-defining taxa were recorded. In this paper, conodonts from the Daliantang Formation at the Daliantang section (Guangnan, southeastern Yunnan), one of the representative sections of the transitional facies between the benthic Xiangzhou facies and the pelagic Nandan facies, are investigated. The conodont fauna shows a remarkably high species or subspecies diversity, with fourteen taxa that are assignable to the notoperbonus Zone and inversus Zone. Five polygnathid species are described: P. gronbergi Klapper and Jonson, P. inversus Klapper and Jonson, Polygnathus sp. B, P. luciae Martínez-Pérez and Valenzuela-Ríos, and P. mashkovae Bardashev. The latter two are reported for the first time from the South China Block. Additionally, three icriodontid taxa are also described, of which L. guangnanensis n. sp. is characterized by distinctly chevron-shaped transverse rows in the anterior part and a well-developed process branching off to the outer side. The new conodont record increases our understanding of the diversification and faunal composition around the lower/upper Emsian boundary in the South China Block. It contributes to the regional and inter-regional biostratigraphical correlation between shallower- and deeper-water facies and also furnishes important South China material for future discussion and deliberation on the position of the lower/upper Emsian boundary.     

Manglietia lawii sp. nov. (Magnoliaceae) from Yunnan, China

Manglietia lawii N. H. Xia & W. F. Liao, a new species of Manglietia from Yunnan, China, is described and illustrated. It is closely related to M. forrestii W. W. Smith, but differs by having villous gynoecium and glabrous tepals.     

Salvia lagochila sp. nov. (Lamiaceae) from Yunnan,China

A new species, Salvia lagochila T. Wang & L. Wang sp. nov. (Lamiaceae) is described from Shangri‐La County in northwestern Yunnan, China. The diagnostic morphological characteristics in relation to closely similar species are discussed. Nutlet micro‐morphology was examined using scanning electron microscopy, and leaf anatomic structures were studied using light microscope. The new species is included in S. subgen. Salvia sect. Eurysphace subsect. Perennes on the basis of its perennial habit, entire upper floral lip and arcuate anther connectives.     

Curcuma gulinqingensis sp. nov. (Zingiberaceae) from Yunnan,China

A new species of Curcuma L. is described and illustrated, viz. Curcuma gulinqingensis N. H. Xia & Juan Chen. The new species is similar to C. amarissima Roscoe, but differs in the following characters: rhizomes lemon yellow inside; blades with a ca 2 cm broad purple cloud along the midrib above the middle, glabrous; coma bracts pale red, purple except the white base, elliptic, obtuse at apex; fertile bracts pale green with purple around the margin and the top, elliptic, obtuse at apex.     

Cephalanthera humilis sp. nov. (Orchidaceae) from Yunnan,China

Cephalanthera humilis X. H. Jin, a new species from Yunnan, China, is described and illustrated. The new species is closely related to C. calcarata but differs from it by having an entire lip without spur at base and the stigma on top of the column.     

Ligularia qiaojiaensis sp. nov. (Asteraceae) from Yunnan,China

Ligularia qiaojiaensisY. S. Chen & H. J. Dong sp. nov., known from two localities in northeastern Yunnan province of China, is described, illustrated and compared with similar species.     

Didymocarpus tonghaiensis sp. nov. (Gesneriaceae) from Yunnan,China

Didymocarpus tonghaiensis J. M. Li & F. S. Wang sp. nov. from Yunnan, China, is illustrated and described. It is morphologically similar to D. stenanthos C. B. Clarke, but differs by having a densely glandular peduncle, 5‐lobed calyx with lobes that are free to the base, larger corolla, anther with white woolly hairs and a densely glandular‐hairy capsule.     

Carex zhejiangensis sp. nov. (Cyperaceae) from Zhejiang,eastern China

Carex zhejiangensis X. F. Jin, Y. J. Zhao, C. Z. Zheng & H. W. Zhang, a new species of Carex sect. Rhomboidales sensu Kükenthal (Cyperaceae) from Zhejiang, eastern China, is described with illustrations. This new species is morphologically similar to C. filipes and C. macroglossa. Compared to C. filipes, C. zhejiangensis has elongated rhizomes, scattered culms, rather densely flowered pistillate spikes, achenes shortly stipitate at the base, and styles erect at the base. In contrast, C. filipes has short rhizomes, caespitose culms, sparsely flowered pistillate spikes, achenes obscurely stipitate at the base, and styles curved at the base. C. zhejiangensis differs from C. macroglossa by having elongated rhizomes and scattered culms, pistillate scales awned at apex, and perigynia contracted to a narrowly infundibuliform beak at apex. Diagnostic morphological characters, which are based upon population sampling, were analyzed in Carex zhejiangensis sp. nov., C. filipes and C. macroglossa.     

Photinia taishunensis sp. nov. (Rosaceae) from Zhejiang,eastern China

Photinia taishunensis G. H. Xia, L. H. Lou & S. H. Jin (Rosaceae, Spiraeoideae) from Zhejiang, China, is described and illustrated. It has previously been confused with P. lochengensis Yü, but differs in details of habit, leaf size, leaf shape, inflorescence, flower size and pubescence. The pollen grains of P. taishunensis are monads, elliptical with trisulcate apertures, and the exine is rugulose, dotted with sparse punctures.     

Dendrocalamus menglongensis sp. nov. (Poaceae–Bambusoideae) from Yunnan,China

A new species Dendrocalamus menglongensis Hsueh & K. L. Wang ex N. H. Xia, R. S. Lin &Y. B. Guo is described and illustrated from Xishuangbanna, Yunnan, China. It differs from D. giganteus by e.g. shorter internodes, 4–5 florets, a perfect terminal floret and persistent culm sheaths. A key to the new species and the other 7 species of Dendrocalamus known from Xishuangbanna is provided.     

Didymocarpus dissectus sp. nov. (Gesneriaceae) from Fujian,eastern China

A new species of Gesneriaceae, Didymocarpus dissectus Fang Wen, Y. L. Qiu & Y. G. Wei, from Fujian province, China, is described and illustrated. It is similar to D. heucherifolius in flower shape, but can be easily distinguished by leaf blade shape, split extent of calyx and equal calyx lobes, indumentum of corolla and number of staminodes.     

Carex qingliangensis sp. nov. (Cyperaceae) from Zhejiang, eastern China

Carex qingliangensis D. M. Weng, H. W. Zhang & S. F. Xu, a new species of the Cyperaceae from Zhejiang, China, is described with illustrations. The new species is morphologically similar to C. dolichostachya Hayata and C. tianmushanica C. Z. Zheng & X. F. Jin, but differs from the former in having perigynia sparsely pubescent and achenes constricted into a short neck at apex. It differs from the latter in having achenes not contracted in the middle part.     

Pleurospermum tripartitum sp. nov. (Umbelliferae) from western Yunnan,China

Pleurospermum tripartitum Pu, R. Li & H. Li, a new species of Umbelliferae from western Yunnan, China, is described and illustrated. It is closely similar to P. macrochlaenum K. T. Fu & Y. C. Ho, but differs by having unbranched stem, conspicuous calyx teeth, and white petals.     

Ligusticum gongshanense sp. nov. (Umbelliferae) from western Yunnan,China

Ligusticum gongshanense Pu, R. Li & H. Li, a new species of Umbelliferae from western Yunnan, China, is described and illustrated. It is closely similar to L. franchetii H. de Boissieu, but differs by having unbranched and light yellow stem, white petals, and styles shorter than stylopodium.     

Calanthe yaoshanensis sp. nov. (Orchidaceae) from northeastern Yunnan,China

A new species of Orchidaceae, Calanthe yaoshanensis Z. X. Ren & H. Wang from northeastern Yunnan, China, is described and illustrated. It is morphologically similar to C. brevicornu Lindley, from which it differs by having a glabrous column and an elliptical middle lobe with three triangular lamellae. The morphological differences between C. yaoshanensis and related species are discussed. The habitat was investigated and its conservation status was assessed as a ‘Critically Endangered’ (CR).     

Hoya tengchongensis sp. nov. (Apocynaceae,Asclepiadoideae) from Yunnan,China

Hoya tengchongensis, a new species of Apocynaceae, subfamily Asclepiadoideae from Yunnan, China, is described and illustrated. The new species is morphologically similar to Hoya serpens in its creeping habit, bearing small and suborbicular leaves, and adaxially tomentose corolla. However, H. tengchongensis differs from H. serpens in corolla size (ca 7 mm versus ca 12 mm in diam) and corona morphology (corona lobes slightly ascending versus erect).