How to Evaluate Taxa with Poorly Known Taxonomy

Portugaliae Acta Biol. 20: 25-36. Lisboa, 2002

HOW TO EVALUATE TAXA WITH POORLY KNOWN TAXONOMY

Jiří Váňa Department of Botany, Charles University, Benátská 2, CZ-128 01 Praha 2, Czech Republic. [email protected]

Váňa, J. (2002). How to evaluate taxa with poorly known taxonomy. Portugaliae Acta Biol. 20: 25-36. Problems with evaluation of the taxa with poorly known taxonomy are discussed. The problems are presented on 13 taxa of liverworts and one of hornworts. As the results, there are three possibilities how the poorly known taxa should be evaluated: not to include in the Red Lists, include as DD (Data Deficient) or formerly as K (Insufficiently Known) or place the taxa in the normal Red List categories (CR, EN, VU). The last option is preferred. Key words: Bryophytes, Red list criteria, taxonomy.

Váňa, J. (2002). Avaliação do estatuto de ameaça de taxa poucos conhecidos. Portugaliae Acta Biol. 20: 25-36. Neste trabalho são discutidos os problemas que surgem com a avaliação das ameaças de taxa pouco conhecidos sob o ponto de vista taxonómico. São referidas as dificuldades existentes com 13 taxa de hepáticas e de uma anthocerota. Como resultado são apresentadas três possibilidades de avaliação deste tipo de espécies para serem incluídas nas Listas Vermelhas: DD (Data Deficiente) para as anteriores K (Insuficientemente Conhecidas) ou integração nas novas categorias das Listas Vermelhas (CR, EN, VU). A integração nestas últimas categorias é sempre preferível. Palavras chave: Briófitos, Listas Vermelhas, taxonomia, estatuto de ameaça.

INTRODUCTION There are many taxa in all taxonomic groups, which are poorly understood and need clarification. Naturally the same is true for bryophytes. Some taxa with poorly known taxonomy may be classified as threatened, along with well- understood taxa that are threatened. Based on this fact, they can be and sometimes are included in Red Lists or Red Data Books. As an example, in the 26 JIŘÍ VÁŇA

Red Data Book of European Bryophytes (ECCB 1995) 50 bryophyte taxa (11 liverworts and 39 mosses) presenting taxonomic problems are mentioned. This number is naturally only approximate; the number of critical taxa changes and may increase or decrease with increasing knowledge and critical study of some groups. The question – how these taxa can be evaluated – is not easy. Many authors of Red Lists or Red Data Books (including also our committee) simply left these taxa out of consideration. Let me analyse the mentioned problem on some examples from the field of hepaticology, which is more familiar to me than muscology. Naturally many of the critical taxa are not threatened and should not be considered in our sense. But some of them are; I selected 13 species (or species pairs) that demonstrate the problems with those taxa where the taxonomic position is unclear. I give some suggestions, which can be discussed.

Frullania cesatiana De Not. Included in the Red Lists of Bulgaria (R), Italy (R), Spain (K) and Switzerland (R), reported also from Austria, France and Slovenia. MÜLLER (1951-1958) treated F. cesatiana (type from Italy) as a synonym of F. riparia (type from North America). BISANG et al. (1989) reinstated F. cesatiana for the European populations named as F. riparia and united this species with the closely related east Asiatic, very polymorphic species F. muscicola, reported four years ago also for Macaronesia by SÉRGIO (1985). F. muscicola was maintained at the variety rank (as F. cesatiana var. muscicola). SCHUSTER (1992a) treated F. cesatiana as a taxonomic synonym of F. riparia like as MÜLLER. He kept F. muscicola as a separate species and gave the differences separating both taxa. SIM-SIM et al. (1999) presented some small differences between European populations (F. cesatiana) and North American populations (F. riparia) of this species. They suggested using modern biochemical techniques for solving the problem of whether one or two species are exist. SIM-SIM et al. (1995) described Macaronesian populations as the new species F. azorica. Grolle (GROLLE & LONG 2000) studied abundant material including the types of F. riparia and F. cesatiana. He is convinced that F. riparia and F. cesatiana are conspecific as treated by Müller and Schuster. F. muscicola he treated as a separate species. Suggestion: F. riparia is a complex of related taxa variously treated as species, varieties or synonyms. The taxonomic status of European populations of F. riparia (reported also under F. cesatiana or F. muscicola) and maybe also the relation to Asiatic F. muscicola should be tested by biosystematic (molecular) methods. However, and not dependent on the results of taxonomic studies, F. riparia should be included in the Red Lists or left in the present Red Lists because of its threatened status in Europe. This species is probably very rare in HOW TO EVALUATE TAXA WITH POORLY KNOWN TAXONOMY 27 all countries (incl. also Austria, France and Slovenia). It is known only from relatively small areas in the Pyrenees, Alps and Bulgarian mountains.

Frullania illyrica Grolle Described by Grolle (MEYER & GROLLE 1963) from Albania; reported also from Slovenia. Reduced to subspecific level under F. inflata by Schuster (SCHUSTER 1983), later to varietal rank (SCHUSTER 1992a). This species was described on the basis of its few, large oil-bodies in the leaf cells. Recently the Austrian bryologist H. Köckinger (in litt.) studied oil-bodies in Austrian plants of F. inflata. He found they usually have 4-8 small oil-bodies per leaf cell (as usual), but sometimes only 2-3 large ones. The same situation is known from Japan; in some populations only a few, large oil-bodies were found (F. inflata var. magnicorpa Yamada). Therefore, F. illyrica can hardly be maintained and is treated now as a synonym of F. inflata (GROLLE & LONG 2000). Suggestion: This species was, fortunately, not included in national Red Lists (there are no Red Lists in Albania and only one of liverworts in Slovenia). Treated as rare in the European Red List (ECCB 1985), it should be deleted (and the data included in F. inflata).

Marsupella spiniloba R. M. Schust. et Damsh. Only in the Red List of Norway (DD); reported also from Iceland and Sweden. Described recently by SCHUSTER & DAMSHOLT (1987), as a species closely related to M. sprucei, from Greenland and discussed in detail by SCHUSTER (1988). Because of the high polymorphism of M. sprucei (incl. also M. neglecta, which is probably an intermediate form transitional to this species, although the Scandinavian reports belong mostly to M. spiniloba; the central European and also northern North American has not yet been checked) it seems to be not completely clear if a good species or only an Arctic modification is at hand. Also SCHUSTER (l.c.) concluded in his discussion “I have no final opinion as to whether or not the last (= M. spiniloba) is a species distinct from M. sprucei.” This problem should be solved soon in connection with my prepared monograph of the genus Marsupella. Suggestion: At this time we do not have exact data about the taxonomic value of this very rare species. Also the reports are very scattered, so perhaps the distribution is incompletely or imperfectly known (to date known in Europe only from Scandinavia, although it may be present in the central European mountains). For the moment there is no exact data about either the species or it’s the threatened status– thus DD.

Marsupella stableri Spruce Known only from Britain (not from Ireland), where it is more common than the closely related M. boeckii, and outside Europe only from British Colombia. 28 JIŘÍ VÁŇA

Kept as a separate species f.e. by MÜLLER (1951-1958). SCHUSTER (1974) at first treated this taxon only as a variety of M. boeckii. His statement is based on the occurrence of transitional forms between M. boeckii and M. stableri in Greenland (cf. SCHUSTER & DAMSHOLT 1974, SCHUSTER 1988). SMITH (1990) accepted the opinion of SCHUSTER (l.c.). Recently PATON (1999) and GROLLE & LONG (2000) again kept both taxa as separate species. This taxonomic problem should be also solved soon in connection with my prepared monograph of the genus Marsupella. Suggestion: This taxon is not included in the Red List of Britain; its taxonomic status should be clarified. The suggestion for the present time is not to include it in Red Lists (not threatened, and taxonomically not a fully clarified species).

Metzgeria simplex Lorb. ex Müll. Frib. Species included in the Red Lists of Bulgaria (R), Czech Republic (Ex), Germany (DD) and Hungary (R). Reported also from France, Italy and Poland. This poorly known taxon closely related to M. conjugata was probably firstly described as M. conjugata var. minor (SCHIFFNER 1893). Independently, KAVINA (1915) described it as M. furcata subsp. hamatiformis; this author also treated M. conjugata as a subspecies of M. furcata. It was newly described as a species by MÜLLER (1941) on the basis of Lorbeer’s studies. Lorbeer separated this species, as he did some other species (of different value), on the basis of different (in this case haploid) chromosome number (n = 9) from the diploid M. conjugata (n = 18); additional differences were found mainly in the cell size. HATTORI (1955), on the basis of the fact that Japanese populations of M. conjugata are haploid (n = 9) in contrast to European ones, named the Japanese populations as M. conjugata var. japonica. The mentioned variety was elevated later to subspecific rank (KUWAHARA 1958) and finally to specific rank (KUWAHARA 1978). On the basis of the above-mentioned facts GROLLE (1983) concluded that M. japonica and M. simplex might be conspecific (this conclusion was not checked). The earliest name of this taxon (if Grolle’s conclusion is correct) should be, however, M. lindbergii (described by SCHIFFNER 1898), as shown by PIIPPO (1991). SCHUSTER (1992a) reduced again M. simplex and M. japonica to subspecific level (no mention of M. furcata subsp. hamatiformis, which epithet has priority in the subspecific rank) under M. conjugata and presented differences between the subspecies. He did not accept the identity of the European and Japanese populations suggested by Grolle. Finally Grolle (GROLLE & LONG 2000), without referring to Schuster’s opinion, repeated his proposal that M. simplex (= M. conjugata subsp. simplex) might be conspecific with M. lindbergii, M. japonica and M. minor. Suggestion: Whether M. simplex is a good species or only a chromosomal race of M. conjugata should be proved by the use of modern biosystematic and chromosome studies. If not conspecific with M. conjugata, it is probably rare and HOW TO EVALUATE TAXA WITH POORLY KNOWN TAXONOMY 29 threatened in Europe. The main problem is that this taxon may be not correctly recognised and confused with M. conjugata by many authors. The present information about its distribution is therefore somewhat subjective. For the time being, probably include it in Red Lists.

Porella baueri (Schiffn.) C. E. O. Jensen Taxon included in many Red Lists: Belgium (DD), Bulgaria (K), Czech Republic (K), Germany (DD), Poland (E) and Spain (R). Moreover, it is reported from many other countries. MÜLLER (1951-1958) treated it, as a separate species close to P. platyphylla, but some authors does not accept this opinion. DODDEMA et al. (1971) made the biometrical comparison of vegetative characters of both taxa on European material and found no reliable differences. However, characters of the perianth mouth and elaters, which are regarded as important by several authors (incl. MÜLLER), were not taken into account. Based on this fact GROLLE (1983) did not accept the uniting of both taxa. This problem was recently solved by biosystematic study (BOISSELIER- DUBAYLE et al. 1998, BISCHLER & BOISSELIER-DUBAYLE 1998). They have shown that this taxon is an allopolyploid hybrid of P. cordaeana × P. platyphylla. Suggestion: The distribution, threatened status etc. is surely imperfectly known because of poor knowledge of this species (which has mostly not been separated from P. platyphylla). It probably represents a rare, perhaps threatened, taxon. There have been no hybrid bryophytes in the Red Lists until now (except this one, which was not known as hybrid before), as far as I know. This topic (inclusion of hybrids) needs further discussion.

Porella canariensis (F. Weber) Underw. Species included in the Red Lists of Portugal (R) and Spain (R), known from Macaronesia only. MÜLLER (1951-1958), just after the study of rich material from Teneriffe (the type contains only two fragments of stems), separated this taxon from P. laevigata var. thuja at the specific level. GROLLE (1983) accepted this view, but noted that this species may be merely a luxuriant local race of P. laevigata. No additional study of this taxon has been made until now. GROLLE & LONG (2000) also accepted this taxon as a separate species, but without additional comments. Suggestion: Taxonomic problem not yet solved, but this taxon is probably correctly recognised in all areas of its occurrence. For the time being perhaps keep in local Red Lists (if threatened in the areas); should be left or deleted from the lists when the taxonomic problem has been solved. 30 JIŘÍ VÁŇA

Porella platyphylloidea (Schwein.) Lindb. Reported from many countries, included in some Red Lists: Czech Republic (Ex), Germany (G = presumably threatened), Hungary (V), Poland (E) and Slovakia (V). The species was kept separate from P. platyphylla for a long time (f.e. MÜLLER 1951-1958), at least because of the sharp difference of the North American populations (see f.e. Schuster 1980, which present evidence that both taxa are genetically different). European authors mentioned many times the often-difficult distinction between P. platyphylla and P. platyphylloidea, at least in sterile condition (fertile plants are very rare), cf. f.e. DUDA & VÁŇA (1980) or GROLLE (1983). The biosystematic study made by THERRIEN et al. (1998) has shown that P. platyphylloidea is conspecific with P. platyphylla; this problem is now solved. Suggestion: Because P. platyphylla is until now relatively common species, P. platyphylloidea should be deleted from all local Red Lists.

Riccia duplex Lorb. ex Müll. Frib. Included in the Red Lists of Germany (G = presumably threatened), Hungary (E), Italy (R), Portugal (R) and Spain (R); reported also from Poland and Sweden. On the basis of Lorbeer’s studies on chromosome counts, this taxon was described by MÜLLER (1941) as a diploid species (n = 16) similar and surely related to haploid (n = 8) R. canaliculata. This treatment was also followed in MÜLLER (1951-1958). BERRIE (1964), on the basis of colchicine-treated plants of R. canaliculata, claimed that the monoecious R. duplex “is probably diploid R. canaliculata”. Because Australian populations of R. canaliculata are dioicous, this is questionable. PATON (1973) remains unsure how R. canaliculata and R. duplex are to be separated. This uncertainty is supported by the fact that NEWTON (1971, 1973) reported both n = 8 and n = 16 phenotypes of R. canaliculata. Hence the chromosome number (used by Lorbeer) seems to be inadequate for separation of the two species. NA-THALANG (1980) and also GROLLE (1983) kept R. duplex as separate species. SCHUSTER (1992b) summarises the distinctions of both taxa, but he hesitates: “It remains questionable whether the distinctions noted above adequately separate two species; both appear to be monoecious and R. duplex and R. canaliculata may both be gametophytically diploid.” JOVET-AST (1986) separated both taxa at the species level. However, PEROLD (1990) wrote about R. duplex “? a diploid form of R. canaliculata (BERRIE 1964) (see also STOTLER & CRANDALL-STOTLER 1977)“; she probably only repeated the opinion of other authors. HOW TO EVALUATE TAXA WITH POORLY KNOWN TAXONOMY 31

GROLLE & LONG (2000) kept both taxa as separate species. Suggestion: Probably very rare, separate species; the taxonomic status should be checked using molecular studies. It is difficult to separate R. duplex from R. canaliculata and this fact can influence information on distribution, threat status etc. Should be included in local Red Lists, at least according to the present state of knowledge.

Riccia teneriffae S. W. Arnell Described by ARNELL (1962) from the Canary Islands (Tenerife); already in protologue mentioned as close to R. canaliculata. GROLLE (1983) included this species in the appendix to his list (“The hepatics of areas neighbouring Europe, but lacking in Europe as defined by TUTIN et al. 1964”). Missing in GROLLE & LONG (2000), probably for the above-mentioned reason. Known until now probably only on the basis of the type specimen, it was not examined (at least nothing has been published). It should be checked to determine whether this species is different from R. canaliculata. Suggestion: Check the type; if a good species should be included in the Red List (one locality known).

Scapania glaucocephala (Taylor) Austin and S. scapanioides (C. Massal.) Grolle Very rare taxa, reported only from some localities in northern Europe (S. glaucocephala – Norway, Sweden, Russia, and Germany (R)) and from central European mountains (S. scapanioides = S. vexata C. Massal. – Alps in Italy (E) and Switzerland (R), Tatra Mts. and Beskidy Mts. in Poland). Taxonomically critical taxa, studied in detail by BUCH & FAGERSTRÖM (1946), who maintained them as distinct. In contrast, MÜLLER (1951, 1951- 1958) synonymized S. vexata (= S. scapanioides) with S. glaucocephala. SCHUSTER (1974) disagreed with Müller’s conclusions; he discussed in detail the differences between both taxa and came to the following conclusions: “The … detailed comparison shows that the cited differences between S. vexata (= S. scapanioides) and S. glaucocephala are not as sharp as Buch and Fagerström maintained. However, it is equally clear that Müller’s contention that a single species is involved remains to be demonstrated. I conclude that two species occur…”. GROLLE (1976) wrote about S. scapanioides that it might be “a form of S. glaucocephala”. SCHLJAKOV (1981) again synonymized both taxa, but noted they can be treated as separate species (cf. SCHUSTER), although GROLLE (1976) is of a different opinion. Moreover, GROLLE (1983) and GROLLE & LONG (2000) again separated both taxa at the specific level. POTEMKIN (1998), working on this genus, considers S. glaucocephala = ? S. scapanioides, but with no further comment. 32 JIŘÍ VÁŇA

Suggestion: The problem of whether S. scapanioides is a central European vicariant of boreal S. glaucocephala or only a modification or a form (a variety) of it is not yet convincingly solved. However, because of the extreme rarity of this species (or these species), and their occurrence on decaying wood, threatened taxa – at least in central Europe –are at hand. Surely it should be included in Red Lists, as has been done up to now. Remark: Recently POTEMKIN (1999) suggested synonymizing two other threatened taxa, S. carinthiaca J. B. Jack ex Lindb. and S. massalongoi (Müll. Frib.) Müll. Frib. This opinion was accepted by GROLLE & LONG (2000). Both taxa are also extremely rare and threatened, and included in the Red Lists of all countries of their occurrence.

Scapania parvifolia Warnst. Included in many Red Lists – Britain (DD), Czech Republic (E), Finland (H), Hungary (R), Slovakia (I) and Sweden (R), reported also from Iceland, Norway, Germany, Poland, Ukraine and Russia. Described as a species of the section Curtae; treated as separate species in many floras, checklists etc. (incl. MÜLLER 1951-1958, SCHUSTER 1974, GROLLE 1983). SCHLJAKOV (1981) suggested that it should be treated merely as a form of S. scandica. Typical S. scandica represents a form of the submontane and montane-boreal regions, whereas S. parvifolia of the subalpine- subarctic areas. Formerly only Russian bryologists, mostly students of Schljakov, f.e. POTEMKIN (1993, 1999), KONSTANTINOVA & VASILJEV (1994), accepted this opinion. Recently it was accepted also by GROLLE & LONG (2000). It should be necessary to note that SCHUSTER (1974) considered both mentioned species as “two of the critical taxa, obviously interconnected”. Suggestion: Again the problem should be solved by molecular techniques. If surely conspecific with S. scandica, it should be deleted from many Red Lists (S. scandica is included only in the Red Lists of Bulgaria (R), Czech Republic (V), Germany (D) and Italy (R); it is known from almost the whole area of western, central and northern Europe).

Anthoceros neesii Prosk. This species known to date only from Poland, Czech Republic (Ex), Germany (CR = Critically Endangered) and recently (unpublished) from Austria. On these facts it is regarded as a central European endemic. This taxon was firstly recognised by NEES VON ESENBECK (1838), who named it as Anthoceros punctatus f. cavernosus sf. monocarpus Nees (= A. punctatus var. macrocarpus Nees in Rabenh.). The type was collected in the Karkonosze Mts. in Poland. PROSKAUER (1958) elevated this subforma to specific level and named it A. neesii in honour of the collector. He mentioned two additional localities in the Karkonosze Mts. and one in the Zachodnie HOW TO EVALUATE TAXA WITH POORLY KNOWN TAXONOMY 33

Pomorze area (all in Poland). From the time of the decription this species was reported only from the Czech Republic (DUDA & VÁŇA 1972) and Hessen in Germany (KELLNER 1987). PROSKAUER (1958) separated this species from A. punctatus (= ? A. agrestis) on the basis of the different ornamentation of spores. An interesting character, mostly overlooked, is the length of the sporophyte (only 3 – 7 mm); also the thallus is relatively small. The species was – as described – mostly accompanied at its localities by Notothylas orbicularis and Anthoceros agrestis. Some years ago I checked two specimens (old collections) from the Czech Republic; one was determined by R. Grolle, the other by J. Duda. The characters given by PROSKAUER (l.c.) in the original description could be – unfortunately – only partly confirmed. The distal surface of spores was not covered by bifurcate spines (character of A. neesii), but the spines on the inner faces were very small and sparse (in A. neesii they should be larger and more numerous). Sporophytes were longer than 1 cm (also not in full accordance with the original description). I asked the specialist on Anthocerotaceae J. Hasegawa for his opinion; he confirmed my findings and doubts and he also hesitated about the identity of the specimens. Just recently I again had the opportunity to study material of this species, esp. the recent material collected by my student J. Kučera with H. Köckinger (who found this species in Austria, his determination confirmed by Grolle) on the fields in Austria. Several specimens collected are clearly dominated by (?) A. agrestis. Some plants (somewhat smaller rosettes, but with sporophytes mostly over1 cm long, the same length as in A. agrestis) have the spores corresponding with the spores known to me from the specimens collected in the Czech Republic. Simply speaking, most plants had the typical spores of A. agrestis and some (rare) plants had spores “transitional to spores reported for A. neesii”. I did not check the material from Germany and from Poland, but I can only assume that they are the same. Moreover, checking the populations of A. agrestis from different localities, some spores can be described as to “10 – 15 % transitional to A. neesii” (the spores of checked material of A. neesii are “40 – 60 % transitional”). Suggestion: Because of the very limited occurrence of the mentioned species, there are no other observation and additional data to the description of this species in the literature. I have recently had some doubts as to whether A. neesii should be a good species; but this is a very preliminary idea. Naturally it will now be necessary to study the remaining material available (including the type), check the material in the field, and make cultivation experiments and other studies, including cytological, biochemical, molecular etc. studies. For the time being, the species must be included in the Red Lists because it is a very threatened, very rare taxon with a very limited area of distribution.

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CONCLUSION Examining suggestions on the discussed 13 species, we can see that 4 species should definitely still be included in Red Lists, 3 species included with hesita- tion, 3 species deleted (synonymized with common taxa), 1 species DD, 1 species not taken into consideration and 1 (a fixed allopolyploid) left for discussion. For me there are three possibilities for how the poorly known taxa should be evaluated: 1. Not to include such taxa in the Red Lists or Red Data Books (because of unclear taxonomy, limited state of knowledge, etc.). This is the simplest option, but results in a relatively high degree of subjectivity in the Red List, as taxa that certainly exist (although poorly known or not taxonomically clear) are excluded. 2. Include the taxa in the Red Lists as Insufficiently Known (K) or - recently - as Data Deficient (DD). However, this practice is not fully correct; both these categories should be used for taxa with inadequate information concerning threat status, rather than taxonomic status 3. To include such taxa in the main Red List categories (CR, EN, VU). This may be the best option; it may not be important that some of these taxa will be deleted from the lists in the future because of clarification of their taxonomy. The main problem is that the evaluation of such taxa can be - in some cases - not fully correct, because of poor knowledge etc. The presented data about their occurrence, decline etc. can be influenced by these facts and thus be rather subjective.

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