University, Shanghai, , China c School of Natural Resources and Environment, University of

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1 This article was downloaded by: [Portland State University] On: 24 October 2013, At: 18:40 Publisher: Taylor & Francis Informa Ltd Registered in England and Wales Registered Number: Registered office: Mortimer House, Mortimer Street, London W1T 3JH, UK Diatom Research Publication details, including instructions for authors and subscription information: TWO NEW SPECIES OF PINNULARIA FROM GREAT XING'AN MOUNTAINS, CHINA Yan Liu a b, Chengxin Fu a, Quanxi Wang b & Eugene F. Stoermer c a College of Life science, Zhejiang University, Hangzhou, , China b College of Life and Environment Science, Shanghai Normal University, Shanghai, , China c School of Natural Resources and Environment, University of Michigan, Ann Arbor, MI, 48109, USA Published online: 01 Nov To cite this article: Yan Liu, Chengxin Fu, Quanxi Wang & Eugene F. Stoermer (2010) TWO NEW SPECIES OF PINNULARIA FROM GREAT XING'AN MOUNTAINS, CHINA, Diatom Research, 25:1, , DOI: / X To link to this article: PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the Content ) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at

2 Diatom Research (2010), Volume 25 (l), TWO NEW SPECIES OF PINNULARIA FROM GREAT XING'AN MOUNTAINS, CHINA Yan Lid'*, Chengxin Ful* 'College of Life science, Zhejiang Universiw, Hangzhou , China Quanxi Wang2* 2College of Life and Environment Science, Shanghai Normal University, Shanghai , China Eugene F. Stoermer School of Natural Resources and Environment, University of Michigan, Ann Arbor, MI USA During an extensive survey of diatoms from the Great Xing'an Mountains, China, two unusual species of the genus Pinnularia Ehrenb. were discovered. Based on both light and scanning electron microscopic observations, both species are described as new: Pinnularia subaldenii sp. nov. and Pinnularia paludosa sp. nov. The morphology of both species is compared to other similar species of the genus. Both have no fascia in the central area. Pinnularia subaldenii is distinguished by the clearly different central area and continuous raphe on the valve interior. Pinnulariapaludosa is distinguished by its large dimensions and distinct crescent-shaped markings in the central area. Environmental conditions in the habitats containing the two new species are presented and discussed. INTRODUCTION The Great Xing'an Mountains are located in the northeast of China, at m elevation. This area is characterized by high humidity and low temperatures, and has the highest latitude wetlands and the widest distribution of bogs in China (Niu & Ma 1985). The climate of the Great Xing'an Mountains is typically temperate continental monsoon, with average yearly temperature about -2.8"C, average yearly precipitation greater than 500 mm. It is an important climatic zone, the summer marine monsoon is blocked by the east- slope of the mountains, which have more precipitation than the west slope. The entire mountain region is relatively humid. The east slope of the mountains is also the coldest place of northeast China, evidenced by a large area of permafrost that is found in this region (Lang et al. 1983). The diatom flora of the wetlands in Great Xing'an Mountains is currently under investigation. Starting in August 2004, more than 500 samples from several lakes, ponds, streams, rivers, swamps and peat bogs in different areas in this mountainous area were collected for a diatom distribution study. The most species-rich genus was Pinnularia, with more than 60 taxa observed in these samples. The rich Pinnularia communities offer a unique opportunity to clarify taxonomic identities of many taxa. In this paper, two new Pinnularia species are described, based on detailed morphological investigations using both LM and SEM. When compared with other species with which they share features, it is clear that these two unusual forms should be described as new species. Herein we present descriptions of two new Pinnularia species from the Great Xing'an Mountains of China. *Corresponding authors 'cxfu@zju.edu.cn, 2wangqx@shnu.edu.cn

3 100 Y.LIU, C.FU, Q.WANG &. E.F.STOERMER MATERIAL AND METHODS More than 500 samples were collected and examined from Great Xing an Mountains in July 2004, August 2005, October 2005 and May Habitats collected included lakes, ponds, rivers, streams, swamps and peat bogs. Formalin (4%) was added immediately upon making the collections to fix the samples in the field. Diatom valves were treated with 30% HzOZ and heated to 90 C for about 2 hours. After cleaning, samples were centrifuged and rinsed with water 5 times, each time for 5 minutes at 4000rpm. For light microscope observations, cleaned material was mounted in Canada balsam on coverslips and examined with a Nikon E800 microscope and were photographed using a Nikon DXM1200 digital camera. For scanning electron microscopy (SEM), part of the cleaned suspension was airdried onto copper stubs, the stubs were then sputter-coated with goldpalladium, and observed with a JEOL JSM-6380LV scanning electron microscope. Diatom images were compiled with Photoshop 7.0. Identifications and comparative information on similar species are based on publications by Krammer (2000), Krammer & Lange-Bertalot (1 997), Moser et al. (1995) and Pillsbury & Slavic (2006). RESULTS AND DISCUSSION Pinnularia subaldenii Q. X. Wang 8z Y. Liu, sp. nov. (Figs 1-24) Descriptio: Valvae fere lmeares, margine vix convexa, apicibus late rotundatis, pn longae, pn latae. Raphe lateralis, pork centralibus parvis, ad altus deflexis, fissuris terminalibus formatis similibus signo interrogationis. Area axialis 1/41/3 latitudinis valvae extendens, area centralis rotundata vel rhombiformis, prope symmetrica. Fascia abest. Striae tansapicales radiatae in media parte valvae, convergentes ad apices, 8-10 in 10 pm, lineae speciosae longitudinales nullae. Holotype: Light microscope slides preparation (Shanghai Normal University, Shanghai, China). Figure 6 is of the holotype. Type locality: Crane Lake, Aer Mountain in Great Xing an Mountains, China, altitude m above sea level. From lakeside, attached on aquatic plants. Collection date 14 August 2005: Quanxi Wang & Yan Liu. Etymology: The species name based on the outline that is similar to P. aldenii Pillsbury & Slavik. LM observations (Figs 1-14) Outline linear, sides parallel or slightly convex, slightly tapered to the broadly rounded, not capitate, ends nearly as wide across as the center of the valve, length pm, breadth pm, length-to-breadth ratio : 1. Raphe lateral, the outer fissure weakly curved and proximally bent to the ventral size, central pores small close standing, terminal fissures large,?-shaped. Axial area 1/4-1/3 the valve breadth, linear, narrowing at the apices, central area rhombic-circular, large and from the axial area clearly different without a fascia, sometimes one submarginal stria on one or two sides is absent. Striae 8-10/10 pm, parallel or weakly radiate in the middle, weakly convergent towards the ends. Longitudinal lines absent. SEM observations (Figs 15-24) Striae are multiseriate, consisting of 4-5 rows of small, rounded areolae (Fig. 21). Raphe branches filiform, not swollen in the central area, external proximal raphe ends small, slitshaped, close together and bent in the same direction (Fig. 19). External distal raphe ends question-mark-shaped, often conspicuous in LM. Internally, the raphe is continuous without an intermissio (Fig. 24), and the central nodule is well developed. At each distal end, a small helictoglossa is present (Fig. 22). One row of short slit-like alveoli is observed on the girdle band (Fig. 20).

4 NEW SPECIES OF PINNULARIA FROM CHINA 101 Figs Pinnularia subaldenii sp. nov. Light micrographs of valve views showing the range of variability. Scale bar = 10 pm. Ecology and associated floras The holotype sample was collected in Crane Lake, situated on Aer Mountain. At the time the collection was made, this lake had a ph range of It is situated at altitude of m above sea level. There are large swamps in its surrounding area. This taxon was only found in lakeside habitats, associated with aquatic plants, in a sample with ph 5.5. It is relatively common in this sample. The dominant species in the sample is Tabellariaflocculosa (Roth) Kiitzing, followed by Gomphonema pawulum (Kiitzing) Kiitzing and Nitzschia sp. The species diversity of Pinnularia in this sample is high containing, additionally, P. borealis Ehrenberg, P. borealis var. islandica Krammer, P. gentilis (Donkin) Cleve, P. lata (Brebisson) Rabenhorst, P. obscura Krasske and P. sinistra Krammer were also observed. Remarks The parallel to slightly convex margins, broadly rounded but not capitate ends, and rhombiccircular central area without a fascia, help to distinguish P. subaldenii. The outline, broad axial area, small central pores and question mark shaped terminal fissures connect this species closely with the P. gibba Ehrenb. group, but the distinct feature of the this group - large markings in the proximal part of the central area are absent. There are no markings in the both sides of the valves in this species. The large central area without fascia separates it fiom P. gibba.

5 102 Y. LIU, C. FU, Q. WANG & E.F. STOERMER Figs Pinnularia subaldenii sp. nov. Scanning electron micrographs outlining the principal morphological features. Figs 15, 18. External view of an entire valve. Figs 16, 17. Internal view of an entire valve. Fig. 19. Detail of the central area and central pores. Figs 20, 23. Detail of one of the apices with?-shaped terminal fissure. Fig. 21. Detail of the alveoli structure. Fig. 22. Internal view of the valve apex with the typical helictoglossa. Fig. 24. Internal view of the central area. Scale bars = 10 pm (Figs 15-18), 5 pm (Fig. 24), 2 pm (Figs 19-23). Our new species is similar to P. aldenii Pillsbury et Slavik (Pillsbury & Slavik 2006). In LM both taxa have linear outlines, broadly rounded apices, linear axial areas and rhombiccircular central areas. Although they seem to have a relatively similar morphology, P. subaldenii has sufficient morphological differences (larger dimension and wider axial area) to differentiate it from P. aldenii. The main differences between these two taxa were observed under the SEM. Both of them have multiseriate striae, there are 2-3 rows of areolae in P. aldenii (Pillsbury & Slavik 2006, fig l(d)), while 4-5 rows in P. subaldenii (Fig. 21). In external view, P. aldenii has slightly enlarged and rounded central pores (Pillsbury & Slavik 2006, fig l(a)) and internally its raphe recurved on a central nodule (Pillsbury & Slavik 2006, fig. 1(B, C)). All these features distinguished it well from P. subaldenii.

6 NEW SPECIES OF PIMVULARIA FROM CHINA 103 Pinnularia maculata Krammer & Metzeltin and P. meridiana Metzeltin & Krammer also share some morphological features with P. subaldenii. Pinnularia maculata is larger (Metzeltin & Lange-Bertalot 1998, length pm, breadth pm) than P. subaldenii with capitate, rounded ends, narrower axial area and rhombic-elliptic central area. Pinnularia meridinana is smaller (Metzeltin & Lange-Bertalot 1998, length m, breadth pm) than P. subaldenii, with distinct narrower valves towards the rounded ends and finer striae in 10 pm. These features are sufficient to separate P. subaldenii from the latter two species. Krammer (2000) described P. erratica nov. nom., which has an outline and central area similar to P. subaldenii. The differences between these two taxa are the shape of valve ends and external distal raphe ends; P. erratica has broadly capitate ends and bayonet-shaped distal raphe ends. Compared with P, subaldenii, the striae in P. erratica are more radiate in the middle and more convergent towards the ends. Moser et al. (1995) also reported a similar taxon to this species, P. spec. 3, but no description was given. According to the Moser et al. s figure, P. spec. 3 has a large central area, broadly rounded apices and small, proximal raphe ends that are situated close to one another. But the irregular markings in the central area and the bayonet-shaped terminal fissure refer it to the gibba group. Comparison of this new species with other Pinnularia species is presented in Table 1. Pinnulariapaludosa Y. Liu & Q. X. Wang, sp. nov. (Figs 2546) Descriptio: Valvae lineares, margine recta vel vix convexa, apicibus late rotundatis. Longitudo pm, latitudo pm. Area axialis lata, linearis, circiter 1/3-213 partem latitudinis valvae, area centralis rotundata vel rhombiformis. Raphe lateralis, pork centralibus parvis, fissuris terminalibus formatis similibus P. stornatophora. Fascia abest. Striae transapicales leviter radiantes in media parte, parallelae ad modice convergentes ad apices, in 10 pm. Holotype: Light microscope slides preparation (Shanghai Normal University, Shanghai, China). Figure 25 is of the holotype. Type locality: Wusulangzi Lake, Aer Mountain in Great Xing an Mountains, China. Altitude m, from peat bogs. Collection date 7 October 2005: Quanxi Wang & Yan Liu. Etymology: The species is named paludosa, based on the peat bogs where it was found. LM observation (Figs 25-30) Valve large, linear, sides parallel or slightly convex, ends rounded or slightly cuneately rounded. Length pm, breadth pm, length to breadth ratio :l. Outer fissures a little curved, lateral in the middle of the raphe branches, filiform distally and proximally, weakly reverse-lateral. External proximal raphe ends small, distal ends deflected in the same direction, terminal fissures long, bayonet-shaped, lying in a large elongate-elliptic terminal area. Axial area moderately broad, 1/3-213 the breadth of the valve, linear to linearlanceolate, with only slight reduction in width towards the apices. Central area large, rhombic to round, slightly asymmetrical. No fascia present. There are distinct crescent-shaped markings with a various structures on either side of the central nodule in the central area. Scattered irregular structures continuing along the striae in the axial area. Striae 1&11/10 pm, parallel or slightly radiate in the middle, parallel or weakly convergent at the ends. A longitudinal line is visible in LM.

7 104 Y. LIU, C. FU, Q. WANG & E.F. STOERMER Figs Pinnularia paludosa sp. nov. Light micrographs of valve views showing the range of variability. Scale bar = 10 pm. SEM observations (Figs 3 146) Striae are multiseriate consisting of 4-5 rows of small, rounded areolae (Fig. 31). Raphe branches filiform, weakly swollen in the central area, central pores small, rounded, bent in the same direction (Figs 35; 38), terminal fissures bayonet-shaped, often conspicuous in as in LM. The terminal fissures'extend onto the valve mantle (Figs 36, 37). In the central area a large, irregularly shaped groove appears (Figs 31,32, 35, 38) which is crescent-shaped in the LM; a long groove can be observed next to the striae (Fig. 32). Internally, the central nodule is present but only weakly developed and not covering the proximal raphe ends. The internal raphe fissures run next to the central nodule and are interrupted by the intermissio (Fig. 34). The internal proximal raphe ends are hooked backwards in the same direction. A fairly large helictoglossa is present at each valve pole, situated somewhat eccentrically (Figs 39,40). One row of short, slit-like areolae is observed on the girdle band (Figs 32,36). Ecology and associated floras This large new species is rare in the Aer Mountain. It was found epiphytic with mosses in peat bogs. The sampling station of the holotype collection is located on the margin of the lake that has ph 7.1. The species was also found in puddles at the side of the river, that has ph 7.8. Species diversity is relatively high in both of the habitats but there are no particularly dominant species present. Other species and genera that appeared in the collections include Meridion circulare (Greville) Agardh, Navicula clyptocephala Kutzing, Navicula radiosa Kutzing, Pinnularia acrosphaeria (Brebisson) W. Smith, Gomphonema pawulum (Kutzing)

8 NEW SPECIES OF PINNULARIA FROM CHINA 105 Kiitzing, Rhopalodia gibba (Ehrenberg) 0. Miiller and Hantzschia amphioxys (Ehrenberg) Gmnow. Although Van de Vijver & Gremmen (2006) stated that larger-celled diatoms such as big Pinnularia, Surirella or Cymbella taxa rarely form large populations, we also trust that this taxon is more common in Great Xing an Mountains than we have documented here. Figs 31,32. Pinnulariapaludosa sp. nov. SEM. External view of an entire valve. Scale bars = 10 pm. Remarks Pinnularia paludosa shares some morphological features with two other Pinnularia species, P. stomatophora (Gmnow) Cleve and P. spitsbergensis Cleve. All of these have a lateral raphe, large bayonet-shaped terminal fissures, crescent-shaped markings in central area and scattered irregular structures continuing along the striae in the axial area.

9 106 Y. LIU, C. FU, Q. WANG & E.F. STOERMER Figs Pinnularia paludosa sp. nov. SEM. Fig. 33. Detail of one of the apices with bayonet-shaped terminal fissure. Fig. 34. Internal view of the central area. Figs 35,38. Detail of the central area and central pores. Figs 36,37. The terminal fissures are running with their major part in the valve mantle. Figs 39,40. Internal view of the valve apex with the typical helictoglossa. Scale bars = 5 pm (Figs 33-38), 2 pm (Figs 39,40).

10 NEW SPECIES OF PINNULARIA FROM CHINA 107 Figs Figs 41, 42. Pinnularia paludosa sp. nov. SEM. Fig. 41. External view of an entire valve. Fig. 42. Internal view of an entire valve. Figs 43,44. Pinnularia spitsbergensis. SEM. Fig. 43. Detail of the central area and central pores. Fig. 44. Detail of one of the apices with bayonet-shaped terminal fissure. Figs 45, 46. Pinnularia stomatophora. Fig. 45. Detail of one of the apices with bayonet-shaped terminal fissure. Fig. 46. Detail of half of the valve with central pores and one of the apices. Scale bars = 10 pm (Figs 41,42,46), 5 pm (Figs 4345).

11 ~ ~ ~ ~.According to Pillsbury & Slavik (2006); According to Metzeltin & Lange-Bertalot (1998); According to Gammer (2000). Table 1. Comparison table of species similar to P. subaldenii. Length Breadth r Striae I10 urn Outline Axial area Central area Ends P. subaldenii P. aldenii P. meridian pm continuously widened from the ends to the central area rhombic, large broadly rounded, capitate pm pm pm w 6&110 pm pm pm pm 9-12 pm pm 1CL13.5 pm r linear linear linear-elliptic rhombic- linear rhombiclanceolate to lanceolate elliptical, linear, narrowing linear, narrowing linear, linear linear at the apices at the apices continuously widened from the ends to the central area rhombic-circular, rounded to rounded to large large large rhomboid, nearly rhomboid nearly symmetrical symmetric broadly rouned nearly as wide as narrower than the broadly capitate broadly rounded, the center of the center of the valve swollen capitate valve Terminal fissure Large,?-shaped 1 hooked like 1 large,?-shaped large, bayonetshaped Fascia absent absent absent P. erratica3 P. maculata2 P. gibba3 large,?-shaped large,?-shaped absent absent small symmetric or asymmetric fascia

12 NEW SPECIES OF PINNULARIA FROM CHINA 109 Pinnularia stomatophora is much smaller with obtusely to cuneate rounded ends, a small fascia in the central area and more radiate and convergent striae (Krammer 2000). These three features are sufficient to separate P. stomatophora from P. paludosa. Pinnularia spitsbergensis is quite similar in outline to P. paludosa but it is also smaller and has a marginal fascia in the rhomboidal central area, and fewer and more parallel striae. Under the SEM, P. stomatophora has slightly enlarged slit-shaped proximal raphe ends (Fig. 46). Pinnularia spitsbergensis also has slit-shaped proximal raphe ends (Fig. 43), while proximal raphe ends in P. paludosa are small, and enlarged foramen rotundum-shaped. CONCLUSION Due to the limited distribution, it is difficult to clearly discern the preference habitats of these two new Pinnularia species. A number of taxa in Great Xing an Mountains investigated have been put aside for future investigations, either because of their low abundance or sporadic occurrence in the samples. The description of these two new species indicates that there are still many unusual species in these mountains and further investigations are needed. ACKNOWLEDGEMENTS This subject was supported by National science foundation of China (Grant Nos & ), and Leading Academic Discipline Project of Shanghai Municipal Education Commission (J50401). We thank two anonymous reviewers for insightful and comprehensive comments that have substantially improved the manuscript. REFERENCES KRAMMER, K. (2000). The genus Pinnularia. Diatoms ofeurope, 1, KRAMMER, K. & LANGE-BERTALOT, H. (1997). Bacillariophyceae. In: Siisswasserflora von Mitteleuropa (H. Ettl, J. Gerloff, H. Heynig & D. Mollenhauer, eds), Band 2/ pp. Gustav Fischer Verlag, Stuttgart, New York. LANG, H. Q., ZU, W. C. & JIN, S. R. (1983). Swamps in China. 269 pp. Shandong Science & Technology Press, Jinan. METZELTIN, D. & LANGE-BERTALOT, H. (1998). Tropical Diatoms of South America I: About 700 predominantly rarely known or new taxa representative of the neotropical flora. Zconographia Diatomologica, 5, MOSER, G., STEINDORF, A. & LANGE-BERTALOT B. (1995). Neukaledonien. Diatomeenflora einer Tropeninesel. Bibliotheca Diatomologica, 32, NIU, H. G. & MA, X. H. (1985). Swamps in our country. 180 pp. The Commercial Press, Beijing. PILLSBURY, R. W. & SLAVIK, K. A. (2006). Pinnularia aldenii sp. nov., a diatom from acidic habitats in Northern Michigan. Diatom Research, 21, VAN DER VIJVER, B. & GREMMEN, N. (2006). Three new moss-inhabiting diatom species from sub- Antarctic Marion Island. Diatom Research, 21, Manuscript received May 2009; accepted for publication December 2009.