J Hallori BOI. Lab. No. 97: 249-261 (Jan. 2(05) STUDIES ON THE GENUS ASTERELLA (AYTONIACEAE) VI: INFRAGENERIC CLASSIFICATION IN ASTERELLA I DAVID G. LONG ABSTRACT. A review and assessment are presented of the three existing classifications of species within the genus Asterella. Based on recent morphological and molecular studies additional charac­ ters such as spore colour and ornamentation are considered important in classification. A new sub­ generic classification is presentee!, which groups the 48 provisionally accepted species into five sub­ genera, Asterella, Saccatae, Wallichianae, Phragmoblepharis and Craciles. Subgenus Asterella is di­ vided into two sections, Asterella and Brachyblepharis, subg. Wallichianae into two sections, Wal­ Uchianae and Cal!fornicae, the latter described as a new section containing only A. eaU/arnica. Subg. Phragmoblepharis cannot be satisfactorily divided into sections at present. A key is provided to the subgenera and sections along with descriptions and a list of accepted species in each. INTRODUCTION The genus Asterella P.Beauv. is the second largest genus of Marchantiales (after Ric­ cia) with approximately 80 species according to Bischler (1998) and is almost world-wide in distribution, but it remains inadequately known in many parts of the world. Recent as yet unpublished revisionary work on Asterella in Eurasia and South and Central America (Long, 2000; Long, in press; Long, in prep.), as well as molecular phylogenetic work on a range of species (Long, Moeller & Preston, 2000) has increased knowledge and under­ standing of the genus sufficiently to attempt a new classification of the species. The genus is now considered to contain about 48 species, but this will be further reduced when Aus­ tralasian species are revised. The recent studies have demonstrated that the existing classifi­ cations are both incomplete and inadequate particularly in the characters they incorporate, and that there are additional characters which can be utilised and which may more accu­ rately reflect affinities and phylogeny of species. It is therefore intended that the new classi­ fication will be both of practical value in grouping species and at least in part reflect phy­ logeny although the phylogenetic studies only included a selection of species. PAST CLASSIFICATIONS Three classifications of species of Asterella have been published, the first two under the synonymous genus Fimbriaria Nees, by Gottsche, Lindenberg & Nees (1844- 1847) and Stephani (1898- 1900) and the most recent by Grolle (1976, 1989). Other recent treat­ ments such as that by Schuster (1992) are based on Grolle's system. The three classifica­ tions are shown in Tables I, 2 and 3, and are considered in turn. 1. Gottsche et al. (1844- 1847) The first classification of the genus (Table I) was published by the three leading Euro- I Royal Botanic Garden, Edinburgh EH3 5LR, u.K. 250 1. Hattori Bot. Lab. No. 97 2 0 0 5 Table 1. Classification of species of Fimbriaria Nees by Gottsche, Lindenberg & Nees (1844- 1847). I. Species genuinae, perianthio involucram §2. Perianthia radiata, i.e. horizontaliter evidenter superante. ( = Fimbriaria subgenus divergentia. [pseudoperianth radiating, i. e. Fimbriaria) diverging horizontally ] fpseudoperianth clearlv exceeding involucre] 14. F raddii Corda § I. Perianthia dependentia. 15. F wallichiana Lehm. & Lindenb [pseudoperianth hanging down] 16. F sanguinea Lehm. & Lindenb. 17. F viridis Lehm. & Lindenb. I. F boryana Mont. 18. F abyssinica Gottsche. 2. F pi/osa Taylor 3. Ffragrans Nees 11. Subgenus Brachyblepharis Gottsche et al. 4. F umbonata Wallr. Perianthii 6- 8-fidi laciniae involucro paulo 5. F saccata Nees longiores. fpseudoperianth 6- 8:fid, lobes scarcely 6. F marginata Nees exceeding involucre] 7. F nepalensis Nees 8. F australis Taylor 19. F chilensis Nees & Mont. 9. F nana Lindenb. 20. F venosa Lehm. & Lindenb. 10. F lindenbergiana Corda 21. F leptophylla Mont. I I. F tenella Nees 22. F af'ricana Mont. 12. F blumeana Nees 13. F elegans Spreng. pean hepaticologists of the day, Gottsche, Lindenberg and Nees von Esenbeck (1844- 1847) in their monumental Synopsis Hepaticarum. A total of 22 species of Fimbriaria were treat­ ed (as well as Rhacotheca azorica Bisch. which was kept as a separate genus, but is now synonymized under Asterella africana) from all continents of the world. Seven of their Fimbriaria species are now considered to be synonyms of other Asterella species. Al­ though they used only two characters (pseudoperianth exsertion and orientation), these proved to be very informative characters and their classification is a good foundation for later work. Subgenus Brachyblepharis was described in that work and is still recognised (as a section) and still contains the species they allocated to it. 2. Stephani (1898- /900) Stephani was a prolific author who had access to many new collections in the late 19th and early 20th centuries, such as the herbarium of E. Levier. His major work was the 6-vol­ ume Species Hepaticarum in the first part of which (Stephani, 1898- 1900) he treated 69 species of Fimbriaria (Table 2). Nineteen of these were described as new species, though no key was provided, and with modern taxonomic revision 33 of these are now considered to be synonyms of others. In the final sixth volume (Stephani, 1917- 1925) he added a fur­ ther 22 species of Fimbriaria. His "Obersicht der Arten" (conspectus of the species) arranged the species into four main groups based on carpocephalum shape and then into IS smaller groups based on the shape of the ventral scale appendages, but did not in any way D. G. LONG: Studies on the genus Asterella (Aytoniaceae) VI 251 Table 2: Classification of species of Fimbriaria Nees by Stephani (1898- 1900). A. Capitula disciformia. 34. F khasiana. a. appendicula squamarum brevia, subovata 35. F bachmannii. I. F. leptophylla . 36. F violacea. 2. F. incrassata. 37. F pilosa. 3. F. venosa. 38. F. vesicu/osa. 4. F. raddii. k. appendicula setacea. b. appendicula lanceo/ata. 39. F californica. 5. F. blumeana. 40. F echinella. 6. F. zollingeri. 41. F abyssinica. 7. F. viridis. 42. F sanguinea. c. appendicula dentata vellaciniata. 43 . F multiflora. 8. F. angusta. 44. F. elegans. 9. F. maculata. 45. F. cubensis. 10. F. wallichiana. 46. F bo/anderi. d. appendicula sefacea. 47 . F. stahlii. 11. F atrispora. 48. F lateralis. e. capitula maxima, squamae ignotae. 49. F linearis. 12. F gigantea. 50. F commutata B. Capituli centrum hemisphaericum. 51. F austinii. f. appendicula dentata vellacerata. C. Capitula distincte conica (haud alle umbonata) 13 . F lindmannii. 1. appendicula magna, ovata, obtusa. 14. F. volkensii. 52. F miilleri. IS. F nepalensis. 53. F australis. 16. F africana. 54. F conocephala. 17. F pringlei. 55. F whiteleggeana. 18 . F. muscicola. m. appendicula lanceolata. 19. F wrightii. 56. F caucasica. 20. F persica. 57. F tasmanica. g. appendicula maxima, late ligulata, acuta 58. F subplana. 21. F drummondii. 59. F tenella. 22. F longebarbata. 60 . F mandonii. h. appendicula brevia, oblonga velovata. 61. F macropoda. 23. F. macounii. n. appendicu/a setacea. 24. F canelensis. 62. F. lindenbergii. 25. F. angolensis. 63. F setisquama. 26. F innovans. 64. F. preussii. 27. F vulcanica. o. appendicu/a dentata i. appendicula lan ceo/ata. 65. F. chilensis. 28. F tenera. D. Capitula alte umbonata. 29. F dissoluta. 66. F a/pina. 30. F parvipora. 67. Ffragrans. 31. F wilmsii. 68. F nudata. 32. F marginata. 69. F palmeri. 33. F boryana. 252 1. Hattori Bot. Lab. No. 97 2 0 0 5 Table 3. Classification of species of ASferella P.Beauv. by Grolle (1976, 1989). Subgenus Asterella Subgenus Phragmoblepharis Grolle TYPE: A. lenella (L.) P.Beauv. Section Phragmoblepharis Other species: A. gracilis (EWeber) Underw. TYPE: A. elegans (Spreng.) Trevis. Other species: A. lateralis M.Howe Subgenus Brachyblepharis (Gottsche et al.) Grolle TYPE: A. lepfophylla (Mont.) Grolle Section Pappiae Grolle Other species: A. abyssinica (Gattsche) Grolle TYPE: A. pappii (Gala) Grolle A. a{ricana (Mont.) A.Evans Other species: A. persica (Steph.) M.Howe A. chi/em'is (Nees & Mont.) A.Evans A. dissoluta (Steph.) Grolle Section Lindenbergianae Grolle A. dominicensis S.W.Arnell TYPE: A. lindenbergiana (Nees) Arnell A. khasyana (Griff.) Pande et al. Other species: none . A. fen era (Mitt.) R.M.Schust. A. venosa (Lehm. & Lindenb.) A.Evans Section Saccatae Grolle TYPE: A. saccafa (Wahlenb.) A.Evans Other species: none. build on the earlier classification of Gottsche et al. (1844- 1847). Unfortunately, carpocephalum shape is dependent on maturity and many of Stephani's specimens were inadequate or immature and his observations were often of poor quality. As a result many related species and synonyms (e.g. taxa belonging to subg. Brachyble­ pharis) ended up in several different groups. This classification, far from being an advance on the earlier one, is therefore of little value in arranging the species. 3. Grolle (1976, /989) The third system is that published quite recently by Grolle (1976, 1989), in which he recognised three subgenera: Asterella, Brachyblepharis and Phragmoblepharis, the last subdivided into four sections (Table 3). Grolle used a much wider array of characters, in­ cluding thallus anatomy, ventral scales, carpocephalum shape, involucre, pseudoperianth structure, spore colour and primary spore ornamentation. His treatment is limited by the narrow range of taxa covered, and some characters were not fully utilised e.g. pseudoperi­ anth structure, capsule dehiscence, elater spiralling and spore ornamentation and in addi­ tion no molecular data were available to him. However, it provides an excellent basis for the new classification presented below. EVIDENCE FOR A REVISED iNFRAGENERIC CLASSIFICATION During course of revising Eurasian and Neotropical species of Asterella (Long, 2000; Long, in prep.; Long, in press) a wide range of morphological characters have been studied in detail for 26 species (more than half the total number now accepted). A large number of these are discontinuous characters which are particularly useful for grouping species to­ gether.
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