The Ordovician Acritarch Dactylofusa Velifera Cocchio 1982: A

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Palynology Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/tpal20 The Ordovician acritarch Dactylofusa velifera Cocchio 1982: a biostratigraphical and palaeogeographical index species Wenhui Wangac, Thomas Servaisb, Kui Yand, Marco Vecolie & Jun Lid a School of Earth Sciences and Engineering, Nanjing University, No. 163 Xianlin Road, 210023 Nanjing, China b Géosystèmes, UMR 8217 du CNRS, Université Lille 1, Avenue Paul Langevin, Bâtiment SN5, 59655 Villeneuve d’Ascq, France c Key Laboratory of Economic Stratigraphy and Palaeogeography (CAS), Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, East Beijing Road, 210008 Click for updates Nanjing, China d State Key Laboratory of Palaeobiology and Stratigraphy(LPS), Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, East Beijing Road, 210008 Nanjing, China e Saudi Aramco, Biostratigraphy Group, Geological Technical Services Division, EXPEC 2 Building, Dharan 31311, Saudi Arabia Published online: 22 Sep 2014.

To cite this article: Wenhui Wang, Thomas Servais, Kui Yan, Marco Vecoli & Jun Li (2015) The Ordovician acritarch Dactylofusa velifera Cocchio 1982: a biostratigraphical and palaeogeographical index species, Palynology, 39:1, 125-141, DOI: 10.1080/01916122.2014.944278 To link to this article: http://dx.doi.org/10.1080/01916122.2014.944278

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The Ordovician acritarch Dactylofusa velifera Cocchio 1982: a biostratigraphical and palaeogeographical index species Wenhui Wanga,c*, Thomas Servaisb, Kui Yand, Marco Vecolie and Jun Lid aSchool of Earth Sciences and Engineering, Nanjing University, No. 163 Xianlin Road, 210023 Nanjing, China; bGeosyst emes, UMR 8217 du CNRS, Universite Lille 1, Avenue Paul Langevin, Batiment^ SN5, 59655 Villeneuve d’Ascq, France; cKey Laboratory of Economic Stratigraphy and Palaeogeography (CAS), Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, East Beijing Road, 210008 Nanjing, China; dState Key Laboratory of Palaeobiology and Stratigraphy(LPS), Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, East Beijing Road, 210008 Nanjing, China; eSaudi Aramco, Biostratigraphy Group, Geological Technical Services Division, EXPEC 2 Building, Dharan 31311, Saudi Arabia Dactylofusa velifera Cocchio 1982 is an easily recognisable, fusiform Ordovician acritarch species with a characteristic membrane. The taxonomy of this taxon is revised based on a literature review and on the investigation of new fossil assemblages from sections in South China. Morphological and biometric studies show that a subdivision into three varieties is justified. The taxonomical rank of Dactylofusa velifera var. brevis Albani 1989 is changed and its diagnosis is emended; Dactylofusa velifera var. velifera is the automatically created autonym. An additional new subspecific taxon is erected: Dactylofusa velifera var. sinensis var. nov. The stratigraphical and palaeogeographical occurrences of Dactylofusa velifera are reviewed, indicating that the species was widely distributed around the peri-Gondwanan margin during the Early Ordovician and early Middle Ordovician. Dactylofusa velifera is of biostratigraphical importance because its First Appearance Datum (FAD) can be used to indicate the late Tremadocian. Palaeobiogeographically, its distribution generally corresponds to that of the Early Ordovician ‘messaoudensis-trifidum’ acritarch assemblage in the peri-Gondwanan region. Keywords: Dactylofusa velifera; EarlyÀMiddle Ordovician; acritarch; palaeogeography; biostratigraphy; taxonomy

1. Introduction been revised in detail. These include Frankea (Servais Graptolite and conodont biostratigraphy has been 1993; Vecoli et al. 1999), Peteinosphaeridium-Lilios- widely used in precise international correlations in the phaeridium-Cycloposphaeridium (Playford et al. 1995), Ordovician. Based on the published biozonations, time Dicrodiacrodium (Servais et al. 1996), Arkonia-Striato- slices (TS) and stage slices (SS) provide precise interna- theca (Servais 1997), Aureotesta (Brocke et al. 1997), tional correlations for all major palaeocontinents Arbusculidium (Fatka & Brocke 1999), Pachysphaeri- (Webby et al. 2004; Bergstrom€ et al. 2009). However, dium (Ribecai & Tongiorgi 1999), Sacculidium (Ribecai in sequences where graptolites and conodonts are et al. 2002), Veryhachium (Servais et al. 2007), Coryphi- absent, organic-walled microfossils, such as acritarchs dium (Servais et al. 2008), Ampullula (Yan et al. 2010) and Rhopaliophora (Li et al. 2014, Forthcoming) (for

Downloaded by [Nanjing University] at 21:25 06 March 2015 or chitinozoans, may provide useful data for biostratigraphical correlations. Some acritarch taxa have been more discussion see Yan et al. 2010). Other taxa are shown to have First Appearance Datums (FAD) at dif- still not well understood and in need of detailed revi- ferent stratigraphical levels in the EarlyÀMiddle Ordo- sion of their taxonomy, biostratigraphy, palaeogeogra- vician. These are thought to have strong potential for phy and palaeoecology. the correlation of Global Stage boundaries in the Early Dactylofusa velifera Cocchio 1982 belongs to the and Middle Ordovician, not only for Gondwana, but fusiform acritarchs. It can easily be distinguished also for correlations between different palaeoconti- because of its characteristic veil/membrane (‘velifera’) nents (Li et al. 2003, 2010; Molyneux et al. 2007). The and its short central body (var. ‘brevis’), compared to fundamental, and also the most time-consuming, part most other fusiform acritarchs. This species is easy to of correlation work is to carry out a thorough review recognise and thus has the potential for high biostrati- of the taxonomy of the stratigraphically signiﬁcant graphical and palaeogeographical importance. First taxa. During the past two decades, several EarlyÀMid- occurrences are reported in the late Tremadocian Ara- dle Ordovician acritarch taxa with biostratigraphical neograptus murrayi graptolite Biozone (TS 1c of and/or palaeogeographical signiﬁcance have therefore Webby et al. 2004) in South China and North Africa

*Corresponding author. Email: [email protected]

Ó 2014 AASP À The Palynological Society 126 W. Wang et al.

(Brocke 1996; Vecoli & Le Herisse 2004; Wang et al. margin and upper slope mud-carbonate belt during 2013a). Palaeobiogeographically, Dactylofusa velifera the EarlyÀearly Middle Ordovician (Zhang et al. is a common taxon of the ‘messaoudensis-triﬁdum’ acri- 2002; Yan et al. 2011;Wangetal.2013b). All speci- tarch assemblage from the latest TremadocianÀearliest mens of Dactylofusa velifera were recovered from Floian along the peri-Gondwanan margin. four local EarlyÀMiddle Ordovician-age formations. Well-preserved material from several sections in Lithologically, the Meitan Formation in the Hon- South China allow a detailed investigation of large ghuayuan section from Tongzi is composed of grey- Dactylofusa velifera populations in the assemblages ish-yellow and greyish-green shales intercalated with recovered. This paper revises the taxonomy of Dactylo- nodular limestone beds in the lower-middle part, and fusa velifera based on the new material and a complete thin-bedded sandstones in the upper part. The Dacao literature review, in order to obtain greater precision Formation in the Houping section of Chengkou con- of its biostratigraphical and palaeogeographical sists of muddy limestones and bioclastic limestones, distribution. interbedded with yellow-green and grey-green to dark grey shales. The overlying Yingpan Formation consists of dark grey to black or grey-green shales 2. Material and methods intercalated with bioclastic limestone lenses. The The material analysed in this study is from three locali- Yinchufu Formation in the Nanba section is charac- ties in South China: the Honghuayuan section in terised by grey micritic limestones in the lowest part Tongzi (Guizhou Province), the Houping section in passing into mudstones interbedded with silty mud- Chengkou (Chongqing area) and the Nanba section in stones higher in the formation. Yiyang (Hunan Province) (Figure 1). The occurrences of D. velifera in the three sections Two sections, the Honghuayuan section in can be correlated with the occurrences of graptolite Tongzi and the Houping section in Chengkou, were specimens for which the age is independently determined located in an inner-shelf mud-carbonate belt, (Yan 2007;Fengetal.2009). Numerous specimens have whereas the Nanba section was located in a shelf been recorded in the palynological slides, but this paper Downloaded by [Nanjing University] at 21:25 06 March 2015

Figure 1. Locality map of the TremadocianÀDarriwilian sections investigated in this study. The stars represent the position of the sections: Left. Honghuayuan, Tongzi; Top. Houping, Chengkou; Right. Nanba, Yiyang. Palynology 127

lists only the stratigraphical information of the slides for Group ACRITARCHA Incertae Sedis Evitt 1963 which specimens are illustrated herein. In the Hon- Genus Dactylofusa Brito & Santos 1965 emend. ghuayuan section in Tongzi, Guizhou, Slide AFI1042 is Cramer 1970 from the C. deflexus graptolite Biozone, Slide AFI1048 is from the A. suecicus graptolite Biozone, Slides AFI1070 Type. Dactylofusa maranhensis Brito & Santos 1965 and AFI1074 are from the E. hirundo graptolite Biozone and Slide AFI1093 is from the U. austrodentatus grapto- Original description. (Brito & Santos 1965): Apre- lite Biozone. All of these levels are recorded in the Meitan senta forma de barco, sendo o corpo revestido de Formation. In the Houping section in Chengkou, Slide projeç oes~ claviformes, distribuıdas regularmente em AFI2030 is from the T. approximatus graptolite Biozone linhas longitudinais. Nas extremidades das clavas, ha in the Dacao Formation and Slide AFI2039 is from the cinco ou mais equenos appendices diaitformes, regular- D. eobifidus graptolite Biozone in the Yingpan Forma- mente distribuıdos. tion. In the Nanba section in Yiyang, Hunan, Slides 1101262 and 1101263 are both from the Ar. murrayi Diagnosis. (Brito 1967): Naviform or fusiform vesicle graptolite Biozone of the Yinchufu Formation. with small spines or claviform processes which are A Zeiss Axioskop 2 Plus optical microscope was regularly distributed in longitudinal rows. At the distal used for observation and photography. The slides from end of a process, three or more digitiform appendages Tongzi and Chengkou are housed in the Nanjing Insti- in a regular arrangement may be present. tute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing, China. The slides from Yiyang Remarks. Because only a description was provided, are housed in the Paleontology and Stratigraphy labo- but no type was assigned and no illustrations were pro- ratory, School of Earth Sciences and Engineering, vided, Dactylofusa was published as a nomen nudum in Nanjing University, China. Brito & Santos (1965, p. 57). Eisenack et al. (1976,p. 153) considered the diagnosis of this genus presented by Cramer (1970, p. 19, who indicated that he was ‘restricting’ the circumscription of Dactylofusa)an 3. Systematic palaeontology emendation. More than 30 species have been assigned The abbreviations of the features measured are as fol- to this genus, some of which were originally assigned lows: L D length of vesicle (central body); W D width to the genera Eupoikilofusa Cramer 1970, Poikilofusa of vesicle (central body); Lp D length of processes; Staplin et al. 1965, Leiofusa Eisenack 1938 and Holo- Hv D height of veils; Ns D number of striate rows thuriadeigma Loeblich Jr. 1970 (Fensome et al. 1990). within 10mm; Nv D number of veil rows within the Eupoikilofusa was considered an illegitimate name and visible side of the vesicle. Measurements are given in a junior synonym of Dactylofusa (see Fensome et al. micrometers (mm) and represent the range of 1990). Dorning (1994) considered that four fusiform minimum-average-maximum values of the parameter. acritarch genera had been validly published and were The format of the synonymy list follows the recom- of practical value: Eupoikilofusa with a striate orna- mendations of Matthews (1973). The following abbre- ment; Leiofusa characterised by oval or fusiform vesicles, a hollow test and smooth membranes; Poikilo-

Downloaded by [Nanjing University] at 21:25 06 March 2015 viations are used in the synonymy lists: fusa with fusiform vesicles, ornamented by small, sim- .: determination correct and accepted in this ple and randomly distributed spines or muri, and study; Dactylofusa that differs from the other three genera in having complex short processes arranged in rows. ?: determination questionable; Dorning’s (1994) concept was adopted by Rubinstein non: determination not accepted; & Vaccari (2004), and the four genera were treated as Ã: valid under the terms of the International separate taxa. Commission on Botanical Nomenclature Dactylofusa is also similar to Holothuriadeigma (ICBN); Loeblich Jr. 1970 and Baiomeniscus Loeblich Jr. 1970. v: vidimus; However, Dactylofusa differs from Holothuriadeigma in displaying a navicular vesicle and pointed termina- p: partim; tions rather than having bean-shaped or reniform 1993 (year in italics): this work has a mention of vesicles, as well as hollow, spinose and ﬁnely granulate the species, but without description or illustration processes that may be simple or terminally bifurcate. (determination impossible to control); Specimens of Dactylofusa are ornamented by veils and 1993 (year in Roman): this work contributes to striae arranged in longitudinal rows rather than dis- our knowledge of this species. playing randomly distributed grana as in Baiomeniscus. 128 W. Wang et al.

Currently, Dactylofusa includes species ranging from piliers; la largeur de chaque «aile» diminue vers les the Early Ordovician (Tremadocian) to the Devonian poles.^ Sur certains individus, la membrane se prolonge (Fensome et al. 1990). sur la base de l’appendice.

Possible biological affinities. By definition (Evitt Original diagnosis (translated from French; Cocchio 1963), acritarchs are organic-walled microfossils of 1982). Vesicle fusiform and elongated fusiform, with unknown biological affinity. However, what could narrow poles that continue in a simple and pointed have been the biological affinity of Dactylofusa veli- process. The base of each process is narrow. The mem- fera? Most Palaeozoic acritarchs are considered to brane is shagrinate and displays very thin longitudinal probably represent cysts of marine phytoplankton (e.g. striae. On the central body and parallel to the long axis Downie et al. 1963; Lister 1970;LeHerisse 1989; are located (in opposite position) two ‘wings’ or trans- Strother 1996; Servais 1997). Furthermore, most Ordo- parent membranes supported by thin pillars; the width vician and Silurian acritarchs have distribution pat- of each ‘wing’ diminishes towards the poles. In some terns and morphologies closely similar to the specimens, the membrane can extend to the base of the dinoflagellates (e.g. Servais et al. 2004). Nevertheless, processes. some acritarch morphotypes are clearly not related to the dinoflagellates, nor to other phytoplanktonic Emended diagnosis. Fusiform vesicle with pointed groups. Colbath & Grenfell (1995) considered that poles, or bearing at each pole a simple, conical, acumi- some of the fusiform acritarchs should be classified as nate process of variable length. Processes hollow and chlorophycean algae. In addition, Moyeria Thusu, freely communicating with the vesicle cavity. Some 1973, reported from Late Ordovician non-marine thin, flexible, transparent, longitudinal veils extend deposits, has been suggested by Colbath & Grenfell radially from the central body. In some varieties, the (1995) to be a possible fossil pellicle (cell wall) of a central body surface is sculptured with very fine, euglenid (euglenida, euglenoid), rather than an algal closely spaced striae parallel to the longitudinal axis of cyst, as originally suggested by Gray & Boucot (1989). the vesicle. Such an assignment is based on the surface morphology, whereby the spiral pattern of ridges on the pellicle Remarks. Dactylofusa velifera Cocchio 1982 is an eas- resembles that of some photoautotrophic euglenids in ily recognisable acritarch that has been widely recorded Monomorphina Mereschkowsky, 1877 (Leander 2012). in the literature. The species displays characteristic Dactylofusa velifera resembles Moyeria in some veils or membranes (which led to the species name aspects, and at least in terms of size and morphology it ‘velifera’) and a relatively short central body compared resembles some modern euglenids, such as Phacus. to most other fusiform acritarchs (which led to the sub- However, we follow here the hypothesis of Colbath & specific name ‘brevis’). Grenfell (1995), that D. velifera, as a fusiform acri- Its taxonomic history is somewhat complex, as it tarch, could possibly be compared to the chlorophytes. was originally described by Cocchio (1982) as a species Nevertheless, the biological affinity remains totally of Dactylofusa, but Albani (1989) assigned the species unknown. to Eupoikilofusa. Furthermore, Albani (1989) created the subspecific taxon brevis at the rank of a forma, Downloaded by [Nanjing University] at 21:25 06 March 2015 Dactylofusa velifera Cocchio 1982 emend. nov. although the first subspecific rank to be used should be the variety (varietas D var.) according to Article 4 of Holotype. Cocchio 1982, p. 32, fig. 3. the International Code of Botanical Nomenclature (ICBN) (McNeill et al. 2011). Furthermore, Albani’s Type locality and type horizon. Mouthoumet Massif, forma was described as a nomen nudum (see below). French ‘Departement’ Aude, Chateau^ de Segure sec- With the creation of a subspecific taxon, an autonym tion, located on the regional road D 39 between Tuchan was automatically created, but this was generally and Palairae, 550 m north of the Chateau^ de Segure. ignored by subsequent authors, so that it can be unclear whether they are referring to the autonym or Original diagnosis. (Cocchio 1982): Le test est fusi- the species as a whole. forme et fusiforme et allonge avec des poles^ retrecis, The present study attempts to clarify the taxonomic prolonges par un appendice simple et pointu. La base status of the different taxa: the subspecific taxon brevis de chaque appendice est etroite. La membrane du test is placed at the rank of a variety, Dactylofusa velifera est chagrinee et comporte des stries longitudinales tres var. brevis, following Article 4 of the ICBN. Therefore, fines. Sur le corps central et parallelement a son grand the automatically created autonym is Dactylofusa veli- axe sont implantees (en position opposee) deux «ailes» fera var. velifera (see Article 27 of the ICBN, McNeill ou membranes transparentes soutenues par de minces et al. 2011). Palynology 129

In addition, the large populations of Dactylofusa non. 2005 Dactylofusa velifera Cocchio; Yan & Li, p. velifera from southern China include a third, new vari- 237, 247, [pl. I, fig. 10 (D D. f. var. sinensis var. nov.)] ety for which the name Dactylofusa velifera var. sinen- non. 2006 Dactylofusa velifera Cocchio; Araoz & sis var. nov. is here proposed. A transition from one Vergel, p. 4, fig. 5G. (Late Cambrian/earliest variety to another can be seen in the Chinese assemb- Ordovician?) lages. This suggests that all specimens and all three 2006 Dactylofusa velifera Cocchio; Molyneux et al., p. varieties should be classified within the same species, 21, 26, 31, 33. i.e. Dactylofusa velifera. These three varieties are 2007 Dactylofusa velifera Cocchio; Molyneux et al., p. described and compared below. 148, 150, 153. Dactylofusa velifera Cocchio 1982 var. velifera 2007 Dactylofusa velifera Cocchio; Paris et al., pl. 5, fig. 9. Autonym 2009 Dactylofusa velifera Cocchio; Molyneux, p. 63. v. 2013a Dactylofusa velifera Cocchio; Wang et al., pl. 2, figs 6À8. Plate 1, figures 1À4 Description. The vesicle has a fusiform shape. Each of Synonymy list. Ã1982 Dactylofusa velifera Cocchio, p. the two polar sides has a process, and the two processes 32À33, text-fig. 3, pl. 1, figs 20À21, 24À25. may be different in length. The processes are either 1984 Dactylofusa velifera Cocchio; Tongiorgi et al., pl. short, conical and horn-like, or more elongated, with a 2, fig. 6. narrow base and an acuminate distal termination. The . 1985 Dactylofusa velifera Cocchio; Albani et al., pl. 4, base of the processes, which may be narrow or slightly figs 5, 9. widened, are hollow and can communicate with the 1986 Dactylofusa velifera Cocchio; Fombella, pl. 1, fig. vesicle; several (one to two in optical view) transparent, 32. flexible and delicate veils/membranes surround the . 1989 Eupokilofusa velifera (Cocchio); Albani, pl. 2, vesicle. The veils that extend radially from the central figs 12À19. body are longitudinally parallel to each other. The veil . 1989 Dactylofusa velifera Cocchio; Molyneux & width decreases toward the poles, and the veils do not Dorning, p. 709À711, figs 3CÀD. extend beyond the process bases. The veil surface is . 1989 Dactylofusa velifera Cocchio; Mette, pl. 3, smooth, and has some little folds on it. The vesicle sur- fig. 23. face is ornamented with very fine, closely-spaced, par- 1990 cf. Dactylofusa taggardii Ghavidel-Syooki, allel, longitudinal striae. No excystment structure is pl. 5, fig. 6. observed. 1992 Dactylofusa velifera Cocchio; Dean & Martin, p. 271, pl. 1, fig. 7. Dimensions. (11 specimens measured) L: 21.3À 1993 Dactylofusa velifera Cocchio; Di Milia et al., 27.0À33.8 mm; W:11.3À16.2À19.5 mm; Lp: 3.1À7.3À p. 174. 8.4 mm; Hv: 1.8À3.3À5.2 mm; Ns: 9À10; Nv: 1À2. . 1996 Dactylofusa velifera Cocchio; Martin, p. 7, pl. 1, figs 11, 14, 15, 20. Remarks. Cocchio (1982) named this fusiform acri- p. 1996 Dactylofusa velifera Cocchio; Brocke, p. 353, tarch for its characteristic veils, and distinguished the Downloaded by [Nanjing University] at 21:25 06 March 2015 pl. 1, fig. 12; p. 355, pl. 2, fig. 7À8 [non. pl. 2, fig. 8 simple, conical, acuminate processes at each pole. (D D. f. var. sinensis var. nov.)]. Albani (1989), who assigned the species to Eupoikilo- p. 1998 Dactylofusa velifera Cocchio; Brocke, p. fusa, recognised two different forms and assigned those 199À201, pl. 19, figs 1À3, 6; pl. 20, fig. 4 [non. pl. 19, with a short central body and pointed polar termina- figs 4, 7, 8 (D D. f. var. brevis); pl. 19, fig. 5 (D D. f. tions to Eupoikilofusa velifera forma brevis, referred to var. sinensis var. nov.); pl. 22, fig. 8 (D D. f. var. here as Dactylofusa velifera var. brevis. brevis)]. . 2000 Dactylofusa velifera Cocchio; Li et al., pl. 1, fig. 6. Comparison. Dactylofusa velifera var. velifera differs non. 2000 Dactylofusa velifera Cocchio; Brocke et al., from D. velifera var. brevis in having more or less long, [pl. 2, fig. 3 (D D. f. var. brevis)]. polar processes instead of pointed to slightly rounded 2000 Dactylofusa velifera Cocchio; Servais & Mette, p. terminations (Figure 2). The specimen of Dactylofusa 155. taggardii Ghavidel-Syooki 1990 has a single polar pro- 2003 Dactylofusa velifera Cocchio; Li et al., p. 96. cess and that at the opposite pole was probably dam- 2004 Dactylofusa velifera Cocchio; Vecoli & Le aged. It is not clear if this species is conspecific with Herisse, fig. 4.81. Dactylofusa velifera. The specimen of Dactylofusa veli- . 2004 Dactylofusa velifera Cocchio; Breuer & Vangues- fera recorded by Araoz & Vergel (2006) has no polar taine, pl. II, fig. 3. process, but apparently has a membrane-like structure 130 W. Wang et al. Downloaded by [Nanjing University] at 21:25 06 March 2015

Plate 1. Selected specimens of Dactylofusa velifera var. velifera and Dactylofusa velifera var. sinensis var. nov. from South China, followed by locality, slide number and England Finder (EF) coordinates. Scale bar is 10 mm. 1À4. Dactylofusa velifera var. velifera. 1. Yiyang, Slide 1101262, EF: S37; 2. Yiyang, Slide 1101262, EF: P35/1; 3. Yiyang, Slide 1101263, EF: A49/4; 4. Yiyang, Slide 1101262, EF: U49/3. 5À16. Dactylofusa velifera var. sinensis var. nov. 5. Chenkou, Slide AFI2030-(3), EF: N33; 6. Chenkou, Slide AF12030-1, EF: W42/3; 7. Chenkou, Slide AFI2030-2, EF: V44/3; 8. Chenkou, Slide AFI2030-(1), EF: O29/4; 9. Chenkou, Slide AFI2039-(5), EF: F33/3; 10. Chenkou, Slide AFI2030-2, EF: F49/2; 11. Chenkou, Slide AFI2030-(2), EF: W33/3;12. Chen- kou, Slide AFI2030-1, EF: F53/3; 13. Chenkou, Slide AFI2030-(4), EF: O40/4; 14. Chenkou, Slide AFI2030-(2), EF: W34/2; 15. Chenkou, Slide AFI2030-2, EF: S45/2; 16. Chenkou, Slide AFI2030-(1), EF: T35/2. Palynology 131

Figure 2. Morphological reconstructions of Dactylofusa velifera var. velifera, Dactylofusa velifera var. brevis and Dactylofusa velifera var. sinensis var. nov. a. D longitudinal section; b. D cross section.

enveloping the vesicle. This specimen was recovered p. 1999 Dactylofusa velifera forma brevis (Albani); from a horizon with an uncertain Late Cambrian/Early Rubinstein et al., pl. 4, fig. 4 [non, pl. 4, fig. 6 (D D. Downloaded by [Nanjing University] at 21:25 06 March 2015 Ordovician age. The photograph provided does not f. velifera)] allow a clear attribution to D. velifera; it possibly illus- 1999 Dactylofusa velifera forma brevis (Albani); Rubin- trates a flattened specimen of a membrane-bearing stein & Toro, p. 255À258. galeate acritarch. . 2000 Dactylofusa velifera forma brevis (Albani); Quin- tavalle et al., pl. 1, fig. 13. Dactylofusa velifera var. brevis Albani 1989 emend. . 2000 Dactylofusa velifera Cocchio; Brocke et al., pl. 2, nov. fig. 3. . 2001 Dactylofusa velifera forma brevis (Albani); Plate 2, figures 1À16 Rubinstein & Toro, pl. 1, fig. 3. Synonymy list. nomen nudum 1989 Eupoikilofusa veli- 2002 Dactylofusa velifera forma brevis (Albani); Vergel fera forma brevis Albani, p. 19, pl. 2, figs 17À19. et al. pl. I, fig. 19. 1994 Dactylofusa velifera forma brevis (Albani); Le 2003 Dactylofusa velifera forma brevis (Albani); Fort et al., p. 943. Tongiorgi et al., p. 68À69, pl. 9, fig. 8. . 1994 Dactylofusa velifera forma brevis (Albani); . 2005 Dactylofusa velifera forma brevis (Albani); Tongiorgi et al., pl. 2, figs 8À9, 12. Rubinstein, pl.1, fig. 3. . 1998 Dactylofusa velifera Cocchio; Brocke, p. ?2006Dactylofusa velifera forma brevis (Albani); 199À201, pl. 19, figs 4, 7À8; pl. 22, fig. 8. Achab et al., p. 136, 146, pl. I, fig. 16. 132 W. Wang et al. Downloaded by [Nanjing University] at 21:25 06 March 2015

Plate 2. Selected specimens of Dactylofusa velifera var. brevis from South China, followed by locality, slide number and England Finder (EF) coordinates. Scale bar is 10 mm. 1À16. Dactylofusa velifera var. brevis. 1. Tongzi, Slide AFI1093-(2), EF: N41/3; 2. Tongzi, Slide AFI1093-(3), EF: X56/1; 3. Tongzi, Slide AFI1093-(3), EF: J59/4; 4. Tongzi, Slide AFI1093-(3), EF: H57/3; 5. Tongzi, Slide AFI1074, EF: M49; 6. Tongzi, Slide AFI1093-(2), EF: T47/4; 7. Tongzi, Slide AFI1074, EF: S53/4; 8. Tongzi, Slide AFI1074, EF: R56/3; 9. Tongzi, Slide AFI1093-(3), EF: N35; 10. Tongzi, Slide AFI1093-(3), EF: Y46; 11. Tongzi, Slide AFI1074, EF: H49; 12. Tongzi, Slide AFI1093-(2), EF: N36/3; 13. Tongzi, Slide AFI1093-(3), EF: G53/2; 14. Tongzi, Slide AFI1093-(2), EF: Z47; 15. Tongzi, Slide AFI1093-(3), EF: Z39/1; 16. Tongzi, Slide AFI1074, EF: G47/3. Palynology 133

non. 2007 Dactylofusa velifera forma brevis (Albani); (Albani 1989) to a variety Dactylofusa velifera var. bre- Yan, pl. VII, figs 4, 8À9[D (D. f. var. sinensis var. vis of the species Dactylofusa velifera, as the varietas nov.)]. rank is the first secondary rank below the species in 2007 Dactylofusa velifera forma brevis (Albani); Moly- botanical nomenclature, according to Article 4 of the neux et al., p. 151. ICBN (the forma rank is lower than subspecies and 2007 Dactylofusa velifera forma brevis (Albani); Paris varietas). et al., p. 102. Most of the specimens assigned to Dactylofusa veli- 2007 Dactylofusa velifera forma brevis (Albani); Rubin- fera var. brevis reported from Sardinia, Italy, show stein et al. p. 426. pointed to slightly rounded poles; rarely does the polar . 2009 Dactylofusa velifera forma brevis (Albani); termination bear a very small spine (Albani 1989, pl. 2, Araoz, p. 63, fig. 12B. fig. 19). Later reports of Dactylofusa velifera var. brevis 2013 Dactylofusa velifera forma brevis (Albani); de la from South China, Argentina and Pakistan showed no Puente & Rubinstein, fig. 3. specimens with small polar spines (Tongiorgi et al. 1994; Brocke 1998, Brocke et al. 2000; Rubinstein et al. 1999; Lectotype. (new designation) Albani (1989), pl. 2, fig. Rubinstein & Toro 2001). The specimens of Dactylofusa 18. velifera var. brevis in the present study have rounded poles and no polar spines. The veils in this form do not Emended diagnosis. The fusiform, or oval shaped, decrease toward the poles, but turn around the two vesicle shows pointed to slightly rounded poles. At poles, sometimes forming a ‘visible’ spine (Plate 2,fig- least two (one in optical view), radial, thin veils with a ures 1, 6). If the small spine-like structure in one of the large height are parallel to the vesicle in the longitudi- Italian specimens (Albani 1989, pl. 2, fig. 19) is a real nal axis. These veils are transparent, flexible with some process, it may suggest that the morphology of D. veli- little folds; their surface is smooth. The veils extend fera var. velifera gradually varies towards that of D. veli- beyond the two rounded poles. The vesicle surface is fera var. brevis by a reduction of the length of the ornamented with very fine, closely spaced, parallel, processes until they become pointed polar terminations longitudinal striae/ribs. (Figure 2). However, none of the specimens observed in this study displays a slit or an opening that could be Description. The vesicle has a fusiform shape. Each of interpreted as an excystment structure. the two polar sides has a pointed to slightly rounded Several specimens identified as Dactylofusa velifera pole. Several (one to three in optical view) transparent, var. brevis from Argentina (Rubinstein et al. 1999, pl. flexible and delicate veils/membranes can be observed 4, fig. 6) and South China (Brocke 1996, pl. 2, fig. 8) around the vesicle. The veils that extend radially from have an unusual distribution of the veils. Their vesicles the central body are longitudinally parallel to each are covered with several (5À6 in optical view) transpar- other. The veils extend beyond the two rounded poles. ent veils which are decorated with numerous, strong, The veil surface is smooth and has some small folds on small folds. These specimens are treated here as the it. The vesicle surface is ornamented with very fine, new variety Dactylofusa velifera var. sinensis var. nov. closely spaced, parallel, longitudinal striae. No excyst- (Figure 2). ment structure is observed. Downloaded by [Nanjing University] at 21:25 06 March 2015 Dactylofusa velifera var. sinensis var. nov. Dimensions. (20 specimens measured) L: Plate 1, figures 5À16 28.9À40.7À55.4 mm; W: 16.7À23.0À29.5 mm; Hv: 2.0À4.8À6.5 mm; Ns: 15À16; Nv: 1À2. Synonymy list. (?) 1990 Dactylofusa crossii Ghavidel- Syooki, pl. 8, fig. 5; pl. 11, fig. 6. Remarks. Because only a description was provided, (?) 1996 Dactylofusa crossii Ghavidel-Syooki; Ghavi- but no type was assigned and no illustrations were pro- del-Syooki, p. 400, pl. 2, fig. 2. vided, Eupoikilofusa velifera forma brevis was pub- . 1996 Dactylofusa sp. aff. D. velifera Cocchio; Brocke, lished as a nomen nudum in Albani (1989, p. 18, 19). p. 355, pl. 2, fig. 8. One specimen which shows a pointed polar termina- .1998Dactylofusa velifera Cocchio; Brocke, p. tion and prominent veils and is ornamented with fine 199À201, pl. 19, fig. 5. longitudinal striae on the vesicle surface is therefore 2005 Dactylofusa velifera Cocchio; Yan & Li, p. 237, designated here as the lectotype (Albani 1989, plate 2, 247, [pl. I, fig. 10 (D D. f. var. sinensis var. nov.)]. fig. 18), following Article 9.2. of the ICBN (McNeill v. 2007 Dactylofusa velifera forma brevis (Albani); et al. 2011). Yan, pl. VII, figs. 4, 8À9. In addition, it is proposed to change the rank of the v. 2013 Dactylofusa velifera Cocchio; Yan et al., p. 2, subspecific taxon Dactylofusa velifera forma brevis figs. 3À4. 134 W. Wang et al.

Holotype. Plate 1, fig. 9. absence of polar processes and the absence of short, small, parallel, longitudinal striae on the vesicle Derivation of name. From the Latin sinensis (from surface. The possible excystment is either by simple Sino, China); referring to China where the specimens longitudinal or by subequatorial splitting (with no are from. preferential splitting patterns). On the other hand, no splitting structure is observed in either D. velifera var. Type locality and type level. South China, Chengkou velifera or D. velifera var. brevis in the Chinese assemb- (Chongqing), Houping section, Yingpan Formation, lages. In the type locality, both D. velifera var. sinensis D. eobifidus graptolite Biozone, Slide AFI2039-(5), var. nov. and D. velifera var. brevis were found in the England Finder coordinates: F33/3. same stratigraphical interval. Both taxa were also found in different samples but from the same strati- Diagnosis. Fusiform or oval shaped vesicle with graphical interval. D. velifera var. sinensis var. nov. pointed to slightly rounded terminations. Thin, short was, however, also found in other samples from lower veils parallel to the longitudinal axis of the vesicle are stratigraphical intervals. present. At least 10 (six in optical view) transparent, flexible veils with numerous, strong folds are observed. Simple longitudinal or subequatorial splitting is com- monly observed on the vesicle wall. Comparison and relationship to the other varieties. All three varieties of D. velifera have the characteristic Description. The vesicle has a fusiform shape. Several veils. Biometric investigations based on large popula- radial, thin, short longitudinal parallel veils are tions (Table 1) plotted on a scatter diagram of length/ observed around the vesicle. There are six to 10 veil width ratios show that all specimens display a continu- rows within the visible side of the vesicle. The veils are ous distribution and are concentrated in clusters transparent, flexible and delicate. The veils extend radi- (Figure 3A). However, there is a discontinuous transi- ally from the central body and decrease in height tion between specimens with low (D. velifera var. sinen- toward the poles. The veil surface is smooth and has sis var. nov.) and high (D. velifera var. brevis and D. some short, low folds on it. A simple longitudinal or velifera var. velifera) veils (Figure 3B). Thus, the three subequatorial splitting of the vesicle wall can be varieties are considered here to be conspecific. D. veli- observed; it can possibly be interpreted as the excyst- fera var. velifera differs from D. velifera var. brevis in ment opening. It ultimately may result in the separa- having smaller W/Hv values (8.9À26.6 vs. 3.5À8.3). tion of the vesicle into two subequal ‘hemicysts’. Both D. velifera var. velifera and D. velifera var. brevis have a smaller number of veils than D. velifera var. Dimensions. (66 specimens measured) L: 24.0À34.3À sinensis var. nov. However, the height of these veils is 43.2 mm; W: 17.2À22.6À30.2 mm; Hv: 0.7À1.5À greater than those of D. velifera var. sinensis var. nov. 2.5 mm; Nv: 6À10. Moreover, both D. velifera var. velifera and D. velifera var. brevis have fine, closely spaced, parallel, longitudi- Remarks. This new variety is characterised by the rel- nal striae/ribs on the vesicle surface which are absent in atively large number of veils and their short height, the D. velifera var. sinensis var. nov. Downloaded by [Nanjing University] at 21:25 06 March 2015

Table 1. Biometric comparison of Dactylofusa velifera var. velifera, D. velifera var. brevis and D. velifera var. sinensis var. nov.

Vesicle Vesicle Process Veil Species and length width Vesicle length height subspeciﬁc taxa References (mm) (mm) length/width (mm) (mm) Age

D. velifera (holotype) Cocchio (1982)25À32 15À21 1.8 4À10 3.75À4 Ordovician (TremadocianÀFloian) D. velifera Albani et al. 22À24 11.5À26 1.4À1.9 5À14 3.5À6 Ordovician (1989) (TremadocianÀFloian) D. velifera forma brevis Albani et al. 25À40.5 14À25 1.5À2 À 3.5À6.5 Ordovician (1989) (TremadocianÀFloian) D. velifera var. velifera this study 21.3À33.8 11.3À19.5 1.5À1.9 3.5À8.4 1.8À5.2 Ordovician (Tremadocian) D. velifera var. brevis this study 28.9À55.4 16.7À29.5 1.6À2.1 À 2.0À6.5 Ordovician (Floian) D. velifera var. sinensis this study 24À43.2 17.2À30.2 1.3À1.8 À 0.7À2.5 Ordovician (Floian) var. nov. Palynology 135

Figure 3. A. Scatter diagram of central body length (L) against central body width (W) for specimens of Dactylofusa velifera measured in the present study. The black dots represent Dactylofusa velifera var. velifera, deltas represent Dactylofusa velifera var. brevis and squares represent Dactylofusa velifera var. sinensis var. nov. B. Scatter diagram of L/W ratio against Hv (height of heils)/W ratio for specimens of Dactylofusa velifera.

Ghavidel-Syooki (1990) erected Dactylofusa crossii populations from Sardinia, Italy, that are most proba- but without a diagnosis or description. D. crossii has a bly of earliest Arenig (early Floian) age (Striatotheca- Downloaded by [Nanjing University] at 21:25 06 March 2015 similar outer appearance and size to D. velifera var. Coryphidium assemblage). After these original descrip- sinensis var. nov. The specimens of Ghavidel-Syooki tions, D. velifera has been widely reported as a charac- (1990) are therefore possibly similar to D. velifera var. teristic taxon of the latest Tremadoc-earliest Arenig sinensis var. nov., but a detailed reinvestigation of the (TremadocianÀFloian) messaoudensis-trifidum assem- Iranian material is needed. blage along the periphery of the Gondwanan continent (peri-Gondwanan region) (Figure 4). However, the species was not found in all messaoudensis-trifidum 4. Biostratigraphy and palaeobiogeography of Dacty- assemblages. It was recovered from the messaoudensis- lofusa velifera trifidum assemblage of the Carmarthen district, south Cocchio (1982) first described the characteristic species Wales (Molyneux & Dorning 1989). In Southern Tur- Dactylofusa velifera from the ‘Tremadoc’ and ‘Arenig’ key, D. velifera was first found by Dean & Martin of the Mouthoumet Massif in southern France. Subse- (1992), and later mentioned in the ‘trifidum flora’ from quently, Tongiorgi et al. (1984) reported it from the both the Zap Valley and Hadim areas by Martin upper Arenigian of Central Sardinia, Italy. Albani (1996), who indicated a late Tremadocian to middle (1989) emended the diagnosis of the species, and Arenig age. More recently, D. velifera and D. velifera erected the subspecific taxon Dactylofusa velifera var. var. brevis were found in Turkey by Paris et al. (2007) brevis (orginally at the forma rank) by analysing large from levels assigned to the Dapingian to Darriwillian. 136 W. Wang et al.

Figure 4. A. The stratigraphical distribution of Dactylofusa velifera in the EarlyÀMiddle Ordovician based on a literature sur- vey. a. Yiyang, South China: Wang et al. (2013a, 2013b); belgium: Breuer & Vanguestaine (2004); c. Spain: Mette (1989) and Ser- vais & Mette (2000); d. Wales: Molyneux & Dorning (1989); e. France: Cocchio (1982); f. Algeria: Vecoli & Le Herisse(2004); g1. Turkey: Martin (1996), g2a, g2b. Paris et al. (2007); h. South China: Brocke (1996, 1998), Brocke et al. (2000); i. Argentina: Rubinstein & Toro (2001), Vergel et al. (2002), Rubinstein (2005), Achab et al. (2006) and Araoz (2009); j1. Central Sardinia, Italy: Albani (1989); j2. Tongiorgi et al. (1984) and Di Milla et al. (1993); k. South China: Yan (2007) and Yan et al. (2013); l. Oman: Molyneux et al. (2006); m. South China: Li et al. (2000); n, Pakistan: Tongiorgi et al. (1994), Le Fort et al. (1994) and Quintavalle et al. (2000). B. The palaeogeographical distribution of Dactylofusa velifera in the EarlyÀMiddle Ordovician. Palaeo- geographical reconstruction after Cocks & Torsvik (2002, figure 4). Letters from a to n in Figure 4B share the same references as in Figure 4A. Note the distribution around the margins of the palaeocontinent Gondwana ranging from the South Pole to palae- olatitudes of 30S (according to this reconstruction). E&W: England and Wales. Downloaded by [Nanjing University] at 21:25 06 March 2015 Dactylofusa velifera can now be considered one of according to the stratigraphical correlations by Moly- the most characteristic species of the messaoudensis-tri- neux et al. (2007). fidum assemblage and its FAD can be used to indicate The presence of Dactylofusa in the upper Tremado- the upper Tremadocian. The occurrence of D. velifera cian in the Yangtze Platform has also been noted by in the Tremadocian is confirmed with the occurrence Brocke (1996, 1998), where two taxa, Dactylofusa veli- of a few specimens in some successions of which the fera and Dactylofusa sp. aff. D. velifera (D. velifera var. age is independently known. In the Barriga Shale For- sinensis var. nov. in this study), appear in the P. deltifer mation of southwest Spain, two specimens of Dactylo- conodont Biozone of the Fenghsiang Formation, cor- fusa velifera were reported from the late Tremadocian responding possibly to the upper part of TS 1b and the messaoudensis-trifidum acritarch assemblage by Mette lower part of TS 1c, but the exact correlation of these (1989) and later by Servais & Mette (2000). The Span- levels needs further examination. ish messaoudensis-trifidum assemblage was reported to Breuer & Vanguestaine (2004) recorded Dactylo- correspond to the Araneograptus murrayi graptolite fusa velifera from Belgium, in a single sample of a Biozone or to the Araneograptus murrayi biozone plus succession that is overlain by layers with an occur- potentially the lower part of the Hunnegraptus copiosus rence of latest Tremadocian-age conodonts. These graptolite Biozone, which represents a clear pre- detailed stratigraphical investigations indicate that approximatus graptolite Biozone age (pre-Floian), Dactylofusa velifera appears in sub-assemblage 4 of Palynology 137

the messaoudensis-trifidum assemblage in the English deflexus graptolite biozones and from the Dapingian Lake District, just below the Tremadocian/Floian Azygograptus suecicus and Expansograptus hirundo boundary (Molyneux et al. 2007). In addition, Moly- graptolite biozones in several sections in South China. neux et al. (2006) recorded it from the top of the The records of the species by Paris et al. (2007) in the Andam Formation in Oman. Recently, Wang et al. ornensis and henryi/bulla chitinozoan biozones in Tur- (2013a) recorded the species from the uppermost key confirms that the species can range into the part of the Yinchufu Formation, in levels attributed Dapingian and Darriwillian. to the late Tremadocian Ar. murrayi graptolite Bio- zone (TS 1c) of South China. This confirmed the sug- gestion by Li et al. (2003)thatDactylofusa velifera 5. Summary appears earlier in China (TS 1c) than in higher lati- Based on studies of material from sections in South tudes (TS 1d), although the first occurrence in the China, supplemented by a revision of the published lit- North African sections possibly also lies in TS1c erature, the original diagnosis of the acritarch species (Vecoli & Le Herisse 2004, figure 4.81). Thus, D. veli- Dactylofusa velifera is critically evaluated and three fera is an important and easy recognisable strati- subspecific taxa are established. The rank of Dactylo- graphical index fossil of the Early Ordovician of the fusa velifera forma brevis Albani 1989 is changed to the Gondwanan margin (peri-Gondwana) with a FAD in varietas level. Another subspecific taxon, Dactylofusa the upper part of the Tremadocian Stage. velifera var. sinensis var. nov., is erected here. Dactylo- Although D. velifera first appears in the Tremado- fusa velifera var. velifera is automatically created as an cian and is mainly reported from the Early Ordovi- autonym. All these three varietes show morphological cian messaoudensis-trifidum assemblage, its range also transients and therefore belong to a single species, Dac- extends to the late Early Ordovician to Middle Ordo- tylofusa velifera. vician. Dactylofusa velifera var. brevis was recorded The biostratigraphical range and the palaeogeo- by Tongiorgi et al. (1994) and Quintavalle et al. graphical distribution of Dactylofusa velifera are (2000) from the late early Arenig to the early late Are- reviewed, indicating that the species is biostratigraphi- nig in Pakistan. Li et al. (2000) recorded Dactylofusa cally useful. It first appears in the uppermost Tremado- velifera from the Shihtzupu Formation in Guizhou, cian A. murrayi graptolite Biozone and is common South China, in levels with late Llanvirn (Darriwil- through the upper Lower and the Middle Ordovician. lian) graptolites from the Didymograptus murchisoni Palaeogeographically, Dactylofusa velifera is also sig- graptolite Biozone. Rubinstein & Toro (2001) nificant because its distribution almost coincides with recorded Dactylofusa velifera var. brevis from the Bal- that of the Early Ordovician ‘messaoudensis-trifidum’ tograptus deflexus and Didymograptus bifidus grapto- acritarch assemblage in the peri-Gondwana region. lite biozones in the Proto-Andean Eastern Cordillera. The biological affinity of the species remains unclear. Dactylofusa velifera var. brevis was also recorded by Just as with other fusiform acritarchs, the species is Vergel et al. (2002) and de la Puente & Rubinstein possibly related to the chlorophycean algae. (2013) from the Arenig Tetragraptus akzharensis graptolite Biozone in the Eastern Cordillera of the Central Ardean Basin. Later, this species was reported from Acknowledgements Downloaded by [Nanjing University] at 21:25 06 March 2015 the Dapingian Zanjon Formation and undivided For- The literature research was completed using the John Wil- mation II in the Sierras Subandinas, in northwestern liams Index of Palaeopalynology (JWIP) at the Natural His- tory Museum of London, UK. We thank John Williams, Argentina (Rubinstein 2005; Rubinstein et al. 2010; Steven Stukins and Tom Hill for help with the JWIP. We are Araoz 2009) and from the early Arenig Suri Forma- grateful to Dr. Claudia Rubinstein (Argentina), Reed tion of the central Famatina System, northwestern Wicander (USA) and an anonymous reviewer for their criti- Argentina (Achab et al. 2006). This is noteworthy cal reviews and valuable comments that improved the manu- because no Tremadocian-age D. velifera (s.l.) have script. This is a contribution to the French ANR (National Research Agency) ‘RALI’ (The Rise of Animal Life) project been recorded from this area before; the FAD of D. and to IGCP (International Geoscience Programme) project velifera appears to be later in the Central Andean 591. Basin than elsewhere. Brocke et al. (2000) reported the presence of Dactylofusa velifera from the early Arenigian to the early Llanvirn in several localities Funding from the Yangtze Platform. Specimens attributed to This work was financially supported by the National Natural Dactylofusa velifera var. brevis (but here assigned to Science Foundation of China [Grant No. 41172012, No. 41272012, No. 41372017] and China Postdoctoral Science D. velifera var. sinensis var. nov.) were recorded by Foundation [Grant No. 2014M550313]. WWH acknowledges Yan (2007) from the Floian Tetragraptus approxima- the palaeontology research team of the CNRS (Centre tus, Acrograptus filiformis and Corymbograptus National de la Recherche Scientifique) research unit 138 W. Wang et al.

Geosystems (UMR 8217) that financed a post-doctoral visit Luther-Universitaet of Halle/Saale, Germany, he pursued his at the University Lille 1. career as a Marie Curie Postdoctoral Fellow at the University of Western Brittany in Brest, France. Subsequently, he obtained a postdoctoral position at the University of Lille 1, France, where he became a permanent senior researcher of Author biographies the Centre National de la Recherche Scientifique (CNRS) in WENHUI WANG received her PhD 2004. After many research collaborations and projects with from the University of Nanjing, China in various industrial partners, in 2011 Marco moved to Saudi 2013. She is now an assistant researcher Aramco to pursue a career in the oil industry as a palynolo- at the Laboratory of Palaeontology at gist. Marco’s field of expertise and research focus is Precam- the same institution. Her research inter- brian and Palaeozoic palynology, and its use in solving ests include Palaeozoic palaeontology, geological and palaeobiological questions. These include chiefly Early Palaeozoic graptolites. high-resolution biostratigraphy and subsurface correlation, Recently Wenhui has collaborated with basin analysis, provenance studies, the evolution of oceanic several teams of palynologists. plankton, the origin of plants and the evolution of land plant cover. Marco is currently president of the International Com- mission on the Palaeozoic Microflora within the Commission THOMAS SERVAIS is a research Internationale de Microflores du Paleozo€ıque (CIMP). director at the French Centre of Scien- tific Research (CNRS). He was trained as a geologist at the universities of JUN LI graduated in geology from Namur and Liege in Belgium, and Peking University, Beijing, China in received a PhD on Ordovician acri- 1978. He received his MSc in 1981 and tarchs in 1993. After postdoctoral stud- a PhD in 1991, both from the Univer- ies in Belgium, Germany and the sity of the Chinese Academy of Scien- United Kingdom, Thomas was ces, Beijing. Since 1981, he become a recruited as a CNRS research associate at the University of permanent researcher in the Nanjing Lille 1 in 1997. Most of his research concentrates on Lower Institute of Geology and Palaeontol- Palaeozoic microphytoplankton, but other fields of interest ogy, and was promoted to research pro- include regional geology, macropalaeontology and micropa- fessor in 1999. Jun visited the University of Sheffield, UK laeontology. Thomas has been Secretary of the Acritarch during 1985, and the University of Lille 1, France between Subcommission of the Commission Internationale de Micro- 2000 to 2010. He also visited Central Michigan University, flores du Paleozo€ıque (CIMP), General Secretary of CIMP, USA for three months in 2004. Jun’s research is on Ordovi- President of the Association de Palynologues de Langue cian and Silurian acritarchs. Francaise¸ (APLF), President of the Association Paleontologique Francaise¸ (APF) and leader of the Interna- tional Geoscience Programme (IGCP) project no. 8 503 “Ordovician Palaeogeography and Palaeoclimater”. He is currently President of the International Federation of Paly- References nological Societies (IFPS) and Vice President of the Palaeon- Achab A, Rubinstein CV, Astini RA. 2006. Chitinozoans and tological Association. acritarchs from the Ordovician peri-Gondwana volcanic arc of the Famatina System, northwestern Argentina. Rev. Palaeobot. Palynol. 139:129À149. KUI YAN is an associate researcher at Araoz L. 2009. Microfloras ordovicicas en Sierra de Zenta, Nanjing Institute of Geology and Palae- Cordillera Oriental Argentina. Serie Correlacion Geo-

Downloaded by [Nanjing University] at 21:25 06 March 2015 ontology, China. He graduated in geol- logica 25:37À94. ogy from the Chinese University of Araoz L, Vergel MdM. 2006. Palinologıa de la transicion Geoscience at Wuhan in 2001. In 2007, cambro-ordovıcica en Quebrada de Moya, Cordillera he received his PhD from the Nanjing Oriental, Argentina. Revista Brasileira de Paleontologıa. Institute of Geology and Palaeontol- 9:1À8. ogy. Kui mainly works on the strati- Albani R. 1989. Ordovician (Arenigian) acritarchs from the graphical and palaeogeographical Solanas Sandstone Formation, Central Sardinia, Italy. significance of the Ordovician microphytoplankton of south- Boll. Soc. Paleontol. Ital. 28:3À37. ern China. Specifically he specialises on the study of interac- Albani R, Lelkes-FelvaryG,TongiorgiM.1985.Firstrecord tions between palaeoenvironment and microphytoplankton of Ordovician (Upper Arenigian, Acritarchs) beds in evolution during the Great Ordovician Radiation. Bakony Mts., Hungary. N. Jb. Geol. Palaont.€ Abh. 170:45À65. Bergstrom€ ST, Chen X, Gutierrez-Marco JC, Dronov A. MARCO VECOLI graduated in geol- 2009. The new chrono-stratigraphic classification of the ogy from the University of Pisa, Italy in Ordovician System and its relations to major regional 1993, and received his PhD from the series and stages and to d13C chemostratigraphy. Lethaia University of Queensland, Australia in 42:97À107. 1999 with a thesis on the Cambro- Breuer P, Vanguestaine M. 2004. The latest Tremadocian Ordovician acritarchs of the Sahara messaoudensis-trifidum acritarch assemblage from the Platform, North Africa. After a post- upper part of the Lierneux Member (Salm Group, doctoral position funded by the Euro- Stavelot Inlier, Belgium). Rev. Palaeobot. Palynol. pean Commission at the Martin- 130:41À58. Palynology 139

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