Journ. Hat/ori Bot. Lab. No. 64,' 37-46 (June 1988)

THE PHYLOGENY AND CLASSIFICATION OF MNIACEAE AND RHIZOGONIACEAE (MUSCI)

TIMO KOPONEN1

ABSTRACT: A cladistic analysis of the genus Mnium Hedw. and related taxa suggests that Mnium s. str. is more closely related to the genera of the Rhizogoniaceae than to most of the other genera of the traditional Mniaceae. In the new classification the Mniaceae contains the genera Mnium, Leucolepis Lindb., Trachycystis Lindb., Pyrrhobryum Mitt., Cryptopodium Brid., Hymenodontopsis Hertz. and Leptotheca Schwaegr. and the Rhizogoniaceae contains the genera Rhizogonium Brid., Hymenodon Hook. f. & Wits., Mesochaete Lindb. and Goniobryum Lindb. The new family, Plagiomniaceae, com­ prizing the earlier Mniaceous genera Plagiomnium T. Kop., Orthomnion Wils. and Pseudobryum (Kind b.) T. Kop. is described. The placement of the earlier Mniaceous genera Cinc/idium Sw., Cyrto­ mnium Holmen and Rhizomnium T. Kop. remains uncertain, and they are tentatively placed in the family Cinclidiaceae Kindb. Most of the genera of the Mniaceae in its new limitation occur in South America- Australasia and possibly are Gondwanalandic. Mnium s. str. is Laurasian and Leucolepis is a Pacific Coast endemic to North America. Only one pantropical autoicous species of Pyrrhobryum is present in tropical Africa. Rhizogoniaceae S.str. is Gondwanalandic, and the Cinclidiaceae and Plagiomniaceae are Laurasian.

I NTRODUCTION In the course of studies on the Mniaceae (e.g. Koponen 1981, and the references there) special attention has been paid to the generic classification of the family (Ko­ ponen 1968, 1980, 1982a). A problem discussed several times is the relationship of the genera Mnium Hedw., Leucolepis Lindb. and Trachycysits Lindb. with the genus Rhizogonium Brid. (s. lat.) of the family Rhizogoniaceae. Kabiersch (1936) already pointed out that Rhizogonium shares so many characters with Mnium s. str. and with Trachycystis that these genera probably constitute a monophyletic group. A cladistic analysis of the traditional Mniaceae (Koponen 1968) suggested that the tribe Plagiomnieae (the genera Plagiomnium T. Kop. and Pseudobryum (Kind b.) T. Kop.) are separated by many apomorphous character states from the tribes Mnieae (Mnium s. str., Leucolepis and Trachycystis) and Cinclidieae (Cinclidium Sw., Cyrto­ mnium Holmen and Rhizomnium T. Kop.) and the latter two are also well separated. The tribe Orthomnieae was found very different from the other tribes, and its status was restudied (Koponen 1980). Orthomnieae were found more closely related to P1agiomnieae than to Mnieae or Cinclidieae. The family classification was discussed again (Koponen 1982a), and the separation of Mnieae from Plagiomnieae was pro­ posed at the family level. However, the necessary nomenclatural procedures were not made. The taxonomy and classification of the Rhizogoniaceae have rather recently been

1 Department of Botany, University of Helsinki, Unionink. 44. SF-00170 Helsinki, Finland. 38 Journ. Hattori Bot. Lab. No. 64 198 8 discussed and treated by many authors. Brotherus' (1924) treatment of the Rhizogoni­ aceae contained 7 genera: Bryobrothera Ther., Cryptopodium Brid., Goniobryum Lindb., Hymenodon Hook. f. & Wils., Hymenodontopsis Herz., Mesochaete Lindb. and Rhi­ zogonium Bird. Herzog (1926) described the genus Acantholoma (horn. illeg.; = Bryo­ acantholoma Schultze-Motel) and placed it in the Rhizogoniaceae. Churchill and Buck (1982) reduced it as a synonym of Spiridens Nees (Spiridentaceae) and this was con­ firmed by Koponen et al. (1986). Norris and Robinson (1979) transferred Bryobrothera to Hookeriaceae on the basis of the peristome characters. Manuel (1980) proposed the division of Rhizogonium into two genera, Rhizogonium s. str. and Pyrrhobryum Mitt. Churchill and Buck (1982) transferred the genus Leptotheca Schwaegr. from the A ulacomniaceae to the Rhizogoniaceae and presented a generic key. Stone (1983) studied the taxonomy of Mesochaete and Karttunen and Back (1988) the taxonomy of Hymenodon in detail. In connection with the revision of the Rhizogoniaceae in Western Melanesia (Koponen et al. 1986) I had the opportunity to study the morphology of its species in detail. In that connection the old idea cited above of the possible polyphylesis of Mniaceae again came to my mind. Since each taxonomic unit should be monophyletic the status and relationships of the Mniaceae and Rhizogoniaceae deserve a closer study.

CHARACTERS USED IN THE CLASSIFlCA nON The characters used to separate Mniaceae from the Rhizogoniaceae are the posi­ tion of the archegonia and the growth habit. The species of Mniaceae are all clearly acrocarpic, but the species of Rhizogoniaceae were considered pleurocarpous by Buck and Vitt (1986). Buck and Vitt (1986) proposed a new familial classification of pleurocarpous mosses. They included the Rhizogoniaceae in the Bryales, as have most of the authors since Fleischer (1920) and Brotherus (J 924). However, since Rhizogoniaceae according to them are pleurocarpous, they proposed a superfamily Rhizogoniacanae comprized of Rhizogoniaceae and Spiridentaceae. The second superfamily of their suborder Rhizogoniineae is Racopilacanae corn prized of the Racopilaceae, Hypopterygiaceae and Helicophyllaceae. The three latter families are truly pleurocarpous having a mono­ podial growth habit, but the pleurocarpy of at least some of the species of Rhizogoni­ aceae can be questioned. To my mind both Mniaceae and Rhizogoniaceae are acrocarpous and the ap­ parent position of the archegonia has been misinterpreted. I repeat my earlier opinion (Koponen 1968) that the difference in the position of the archegonium between e.g. Mnium s. str. and some species of e.g. Pyrrhobryum is only illusory. In Mnium the stems bearing terminal perichaetia are actually branches of either a sterile shoot or of another fertile shoot. In Pyrrhobryum sect. Pyrrhobryum the branches bearing pericheatia similarly are branches of sterile shoots, but these fertile branches are short. The basic difference from the true pleurocarpous mosses is that the sterile stems producing T. KOPONEN : Phylogeny and classification of Mniaceae and Phizogoniaceae 39 fertile stems (or branches) do not grow continuously but vegetative reproduction takes place by branching at the bases of the shoots. In Pyrrhobryum sect. Bifariella the perich­ aetia are born laterally at the leafaxils of shoots whose apex does not grow continu­ ously. Cryptopodium finally is an example of a taxon in which both the acrocarpic and pleurocarpic conditions may occur simultaneously. According to e.g. Sainsbury (1955) Cryptopodium has either acrocarpic or lateral archegonia, and these conditions may be present on the same stem. Churchill and Buck (1982) explained this by stating that the sporophytes are terminal and then shortly subtended by a single (or rarely a second) branch. Mnium, Cryptopodium, Pyrrhobryum sect. Bifariella and sect. Pyrrhobryum form an evolutionary series schematically presented in the Fig. 1 on which also the alternative possibilities are given. Fig. I also demonstrates that if the position of the archegonium is emphasized when Mnieae and Rhizogoniaceae are classified we get a

A 90 if'" Go~n,obry um ~ V-1 -7 \)V --7 ~ ~1!iJ .-/'! \ Pyrrhobryum · Sect Pyrrhobryum M\1mum M n,um Cr yptopo d,um Pyrrhobryum Pyrrhobr yum Leptotheeo Sect. Biforiella Sect. Pyrrhobryum "';J Leueolepis Troehyeystis

B

Rhizogon iu m Hymenodon r~r~J Hymenodontopsis Leueolepis Pyrrhobryum c V~ ~~ ~~ ( Mnium Pyrrhobryum Pyrrhobr yum Cryptopodium Sect. Pyrrhobryum Sect. 8iforiollo

FIG. 1 A-c' Hypothetical series showing three possibilities of evolution from an acrocarpic Mnium type position of archegonia to various types of position in Rhizogoniaceae. - A. Series from Mnium through Cryptopodium (with subperichaetial innovations). Pyr­ rhobryum sect. Bifariella (with lateral archegonia on the middle of the stem) to sect. Pyr­ rhobryum (with basal archegonia), and finally to Rhizogonium (either rhizautoicous or with dwarf males). Synoecity has developed several times in Mnium, Goniobryum and Pyr­ rhobryum. - B. A possible evolutionary line from Leucolepis to Pyrrhobryum by the shorten­ ing of the main stem. - C. A series from Mnium to Cryptopodium by shortening of the fertile branch and its gradual movement to a subapical,position. 40 Journ. Hattori Bot. Lab. No. 64 198 8 rather radically different classification from that in use now. Churchill and Buck (1982) share this view, and they even removed the acrocarpic genus Leptotheca to Rhizogoni­ aceae. Mesochaete and Goniobryum are the two genera which are really different from the other genera discussed above. In them many axial archegonia are either basal or occur in the middle part of the shoot. Two hypothetical cladograms of Mnieae-Rhizogoniaceae are presented in Figs. 2 and 3. Plagiomnieae from one side and Racopilaceae from the other side were used as outgroups. Mnieae-Rhizogoniaceae have possibly only one apomorphic character, the stem epidermis rather heavily thickened (Goniobryum differs in having a thin­ walled epidermis). This mayor may not be in connection with the fact that Mnieae­ Rhizogoniaceae have no micronemata (an apomorphic character of Plagiomnieae) but only macronemata (see Koponen 1968), if the rhizoids develop at all on the upper stem parts. It may be pointed out here that Racopilaceae have a completely different rhizoid topography (Koponen et al. 1986). In them the rhizoids consistently arise from the abaxial line of leaf insertion. This rhizoid topography type is rather constantly present e.g. in many species of the family Hypnaceae (see Hedenas 1987). The ancestor of Mnieae-Rhizogoniaceae is supposed to have had an elongate seta, horizontal to nutant capsule, complete bryaceous peristome, small (up to 10 ,urn) laminal cells, ser­ rate multilayered leaf border and the costa toothed at least dorsally but possibly also ventrally. The characters used in creating the cladograms are discussed below. The clado­ grams are "handmade" and have not been tested by using computerized parsimony tests. The apomorphic character state is mentioned first in each pair of characters.

FIRST CLADOGRAM (Fig. 2) I. Costa smooth - toothed. The smooth costa is an apomorphic character and is the only character separating the two main branches of the cladogram (Fig. 2). A toothed costa is lacking in the rest of the traditional Mniaceae. 2. Leaf border cells short - border cells narrow, elongate. As described and illustrated by Stone (1983) Mesochaete has a very strong polystratose border made of elongate narrow cells. Similar borders occur in the traditional Mniaceae, in Mnieae and Cinclidieae. The unistratose border of elongate cells is common in Plagiomnieae and in many other Bryales. Reduction of the leaf border has taken place many times independently (see e.g. Koponen 1982b). In the present cladogram the reduced border is supposed to be a homoplasy in Rhizogonium, Hymenodon, and Trachycystis - Crypto­ podium. In Pyrrhobryum and Cryptopodium the border is bi- to multistratose (and hence marginal teeth geminate) but the border cells are short. Trachycystis flagellaris (Sull. & Lesq.) Lindb. has elongated border cells and this suggests that the species might be removed to the genus Mnium. Compare with caption 11. 3. Archegonia lateral on stems - archegonia terminal on short branches. This character pair is used to separate Goniobryum and Mesochaete from Rhizogonium and Hymenodon. As discussed above the similar stage occurs in Pyrrhobryum sect. T. KOPONEN: Phylogeny and classification of Mniaceae and Phizogoniaceae 41

.;;;.. Q. E E 0 ;, a> E c E :::> :::> 0 '" C :::> >.. ~ 0 0 >.. -u L- C -u u ->.. . a.. 0 '" '" -0 L- 0 0 a> u Q. ..0 ~ 0 a> 0 ..0 0 u 0> C E ~ >.. c 0 2 a> ~ "0 a> ~ C 0 0 :::> "0 u Q. .. N E u L- 0 a> >.. c a. 0 :::> E L- >.. :E a> L- a> >.. >.. L- 0 ~ 0::: ::c ~ -' ~ -' :r: ~ U 9 8 7 15 4 5 5 6 9 13 6

14 3 6 12 6

10 2

c b a

FIG. 2. An assumed phylogeny of Mnieae-Rhizogoniaceae resulting from an apo­ morphic smooth costa being given the priority. a-< indicate the autapomorphies of the group when compared with outgroups Plagiomnieae and Racopilaceae. Apomorphies are marked by dots and homoplasies by bars. The explanation of the figures in the text. 42 Journ. Hattori Bot. Lab. No. 64 198 8

Bifariella. 4. Narrow elongate leaf cells - leaf cells quadrate to short elongate or isodiametric. The leaf cells of Goniobryum are more like those in some species of Bryaceae than in Mnieae-Rhizogoniaceae. 5. Complanate and pseudodistichous asymmetrical leaves -leaves symmetrical, not pseudodistichous. Only Mesochaete and Rhizogonium have this apomorphic character state which is thought to be a parallelism in the latter genus. 6. Capsule erect - arcuate to nutant. As discussed by Koponen (1980) the hori­ zontal to nutant position of the capsule is a plesiomorphic character in the Mniaceae and only in Orthomnieae the apomorphic erect capsule occurs. The same holds true in Rhizogoniaceae. The erect capsule is a homoplasy in Hymenodon, Leptotheca, Hymenodontopsis and Cryptopodium. 7. Reduced endostome - endostome complete. The single peristome of Hy­ menodon was traditionally though to be endostome (e.g. Brotherus 1924, Koponen et al. 1986). Shaw and Anderson (1986) showed that it actually is an exostome and this has been confirmed by Karttunen and Back (1988). The exostome of Hymenodon is rather different from that of the other genera in the Rhizogoniaceae and could be added on the cladogram as supporting apomorphic character. 8. Piliferous leaves - leaves acute to obtuse. This character separating Hymenodon from the other genera was discussed in detail by Koponen et al. (1986) and Karttunen and Back (1988). 9. Mammillose leaf cells -leaf cells smooth. The leaf cells of all species of Hy­ menodon are mammillose (see Karttunen & Back 1988). Mammillose leaf cells occur in two species of Trachycystis as well and are considered there as parallelism. 10. Wide hexagonal to isodiametric leaf cells - small quadrate to short-rectangular leaf cells. This is the only apomorphic character possessed by Mnium in which the smallest leaf cells, up to ca. 15,um wide, occur in M. thomsonii Schimp. and in M. laevinerve Card. 11. Unistratose border - bi- to multistratose border. As discussed under the caption 3 the leaf border comprizing of short cells may be bistratose. The border of Hymenodontopsis is bistratose only at base. 12. Subapical branching - stem branches at base. In Trachycystis and Leucolepis there occurs frequent branching on the stem below the perichaetium so that a tree-like habit may occur. In some species of Pyrrhobryum the sterile shoots may branch pro­ fusely but this character needs more study and, in that connection, the growth habit of Rhizogonium s. str. should also be evaluated. 13 . Extreme differentiation of basal leaves - no or a little differentiated basal leaves. The lower stem leaves of Leucolepis have a hyaline apex and are acuminate and characteristically serrate. 14. Reduced exostome - complete exostome. The peristome of Hymenodontopsis is single and only the endostome is present (for the details see Shaw & Anderson 1986). 15. Short seta - elongate seta. Cryptopodium is the only taxon having apomorphic T. KOPONEN: Phylogeny and classification of Mniaceae and Phizogoniaceae 43 short seta within the mosses under discussion.

SECOND CLADOGRAM (Fig. 3) The cladogram in the Fig. 2 is based on the assumption that the smooth costa

~ a..~ 0 .., ~ E E E E :> :> :> c: C :> Qj 0 ~ >- 0 u ~ 0 >- -u 0 'c .., >- '6.. ... 0 ...0 ...c; 0 0 ...c; u .., 0 .D u E Cl "c: >- "c: a.. .., ...c; 0 0 .2 0 :> 0 0 0 .., ...c; c: N u u ... ;;; c: E :> E ... a. 0 ...c; >- a..., 0 .., >- >- >- () :E :E I .= -' I a.. 0 "" -' 9 8 7 14 15 4 5 t 6 9 13 6 6 6 12

11

10

3

c b a

FIG. 3. A cladogram resulting from a smooth costa considered to be a homoplasy in Goniobryum - Mesochaete and in Rhizogonium - Hymenodon. The scattered distribu­ tion of perichaetia along the stem in Goniobryum - Mesochaete is given priority. Other expla­ nations as in Fig. 2. 44 Journ. Hattori Bot. Lab. No. 64 1 9 8 8

developed only once within the group under discussion. This leads to a solution which may not be natural. If the only meaningful character state connected with the position of the archegonia is given the priority, a different cladogram can be drawn (Fig. 3). Both cladograms have several homoplasies. Of them the erect capsule, the distichous asymmetric leaves and the mammillose leaf cells have evolved many times in various groups of mosses. These characters are autapomorphies separating single genera from each others and do not have influence on the general picture. In addition to the char­ acter pair no. 3 the characters of the laef border and especially the reduction of the border are the key characters. The cladogram in Fig. 3 is more parsimonious than the first cladogram when proposing that the reduction only took place once (character 2).

TAXONOMIC IMPLICATIONS Both of the proposed solutions lead to changes in the family level classification of Rhizogoniaceae and Mniaceae. If the second cladogram (Fig. 3) is accepted the family Rhizogoniaceae disappear altogether and Goniobryum and M esochaete remain orphans. If the first cladogram (Fig. 2) is selected, Rhizogoniaceae remain and contain the genera Goniobryum, Hymenodon, Mesochaete and Rhizogonium. Mniaceae in its new limitation would comprize the genera Cryptopodium, Hymenodontopsis, Leptotheca, Leucoiepis, Mnium, Pyrrhobryum and Trachycystis. I prefer this solution in the present phase of our knowledge. The genera Mesochaete and especially Goniobryum need to be studied more carefully in connection with such other genera as Spiridens and Ca/omnion Hook. f. & Wils. Both solutions leave a number of genera of the traditional Mniaceae without a familial placement. The family Cinclidiaceae Kindb. can be used for the genera of the tribe Cinclidieae. For the genera of the Plagiomnieae a new family needs to be described.

Pfagiomniaceae T. Kop., fa milia nova Tribus Plagiomnieae T. Kop., Ann. Bot. Fennici 5 : 145. 1968. Type : Plagiomnium T. Kop., Ann. Bot. Fennici 5: 148. 1968.

CONSPECTUS The four families and the genera in them are listed below. Plagiomniaceae T. Kop. P/agiomnium T. Kop. Orthomnion Wils. Pseudobryum (Kind b.) T. Kop. Cinclidiaceae Kindb. Cinclidium Sw. Cyrtomnium Holmen Rhizomnium T. Kop. Mniaceae Schwaegr. Mnium Hedw. Leuco/epis Lindb. T. KOPONEN: Phylogeny and classification of Mniaceae and Phizogoniaceae 45

Trachycystis Lindb. Leprotheca Schwaegr. Pyrrhobryum Mitt. Cryptopodium Brid. Hymenodontopsis Herz. Rhizogoniaceae Broth. Rhizogonium Brid. Hymenodon Hook. f. & Wils. Mesochaete Lindb. Goniobryum Lindb.

PHYTOGEOGRAPHY In its earlier limitation the family Mniaceae has been considered as a Laurasian family, although one of the oldest groups of Plagiomnium, Plagiomnium sect. Rostrata has species in South America, Africa and Australasia (Koponen 1981, 1982b). In its new limitation the Mniaceae occur both on the Northern and Southern HemisphereL Leptotheca is totally a Southern Hemisphere genus. The rest of the genera form a com­ plex ranging from Australasia (Cryptopodium) through Melanesia (Hymenodontopsis) to continental Asia (Trachycystis) and Western North America (Leucolepis). Pyrrhobry­ um covers nearly all of that range and has one synoicous pantropical species. Mnium is the only widely spread Northern Hemisphere genus, the southern occurrence of which in New Guinea (Koponen & Norris 1983) must be considered as rather recent. Accordingly, the Mniaceae might well be originally a Gondwanalandic as well as a Laurasian family. If the genus Mnium is considered to be the most advanced of its genera the first possibility seems more probable. All the genera of the new Rhizogoniaceae are mainly Southern Hemisphere taxa, Mesochaete and Goniobryum exclusively so. Rhizogonium occurs in South America and in the Southern Pacific area and Hymenodon has species in South and Central America and Australasia-Melanesia. When limited as in the present paper the family is lacking from Africa. Accordingly, the Rhizogoniaceae in its new limitation is more distinctly Gondwanalandic than the Mniaceae. Of the two other families the Cinclidiaceae is exclusively Laurasian and shares with Mnium only the large leaf cells, multistratose border made of elongate linear cells and the generally similar stem epidermis. The Plagiomniaceae are also mainly Laurasian with the exception of some species of Plagiomnium sect. Rostrata as explained above. The species of Plagiomniaceae have so little in common with either Mniaceae or Cinclidiaceae that they belong to a separate evolutionary line. Early bryologists in­ cluded Plagiomnium and Pseudobryum within Mnium because of the large leaf cells and hence wide leaves. We should remember that the first systems of moss classification were made by bryologists who had field experience only from the European flora. Although many tropical floras are already known we still use old classifications based on limited number of taxa. 46 Journ. Hattori Bot. Lab. No. 64 198 8

ACKNOWLEDGEMENTS: I wish to express my thanks to Prof. Daniel H. Norris who pro­ posed linguistic corrections on the manuscript.

LITERATURE CITED BRoTHERus, V.F. 1924. Musci (Laubmoose) 11. Spezieller Teil. In: A. ENGLER & K. PRANTL (eds.), D ie natiirlichen Pflanzenfamilien nebst ihren Gattungen und wichtigeren Arten insbesondere Nutzpflanzen, 2 Aufl. 10(1) : 129-131 , 143-378. BUCK, W. R. & D . H. VITT 1986. Suggestions for a new familial classification of pleurocarpous mosses. Taxon 35: 21-60. CHURCHILL, S. P . & W. R. BUCK 1982. A taxonomic investigation of Leptotheca (Rhizogoniaceae). Bri ttonia 34: I-I!. FLEISCHER, M. 1920. Natlirliches System der Laubmoose. Hedwigia 61 : 390-400. HEDENAs, L. 1987. North European mosses with axillary rhizoids, a taxonomic study. J . Bryo\. 14: 429-439. HERZOG, T. 1926. Bryophyten der weiteren Indomalaya. Hedwigia 66: 337-358. KABIERSCH , W. 1936. Studien iiber die ostasiatischen Arten einiger Laubmoosfamilien (Mniaceae­ Bartramiaceae). Hedwigia 76: 1-94. KARTTUNEN, K . & S. BACK 1988. New species, subspecies and combinations in the genus Hymenodon (Musci, Rhizogoniaceae). Ann. Bot. Fennici 25 : 89-95. KOPONEN, T . 1968. Generic revision of Mniaceae Mitt. (Bryophyta). Ann. Bot. Fennici 5 : 117- 151. Reprint in: T. DUNCAN & T. F. STU ESSY (eds.), Cladistic theory and methodology. Pp. 103- 137. Van Nostrand Rein hold Company, New York. KOPONEN, T. 1980. A synopsis of Mniaceae (Bryophyta). 11. Orthomnion. Ann. Bot. Fennici 17 : 35- 55. KOPONEN, T. 1981, A synopsis of Mniaceae (Bryophyta). VI. Southeast Asian taxa. Acta Bot. Fennica 117 : 1- 34. KOPONEN, T. 1982a. Generic and family concepts in Mniaceae. Beih. Nova Hedwigia 71 : 249-259. KOPONEN, T. 1982b. The family Mniaceae in Australasia and the Pacific. J. Hattori Bot. Lab. 52 : 75-86. KOPONEN, T. & D . H. NORRIS 1983. Bryophyte flora of the Huon Peninsula, Papua New Guinea. H. Mniaceae (Musci). Ann. Bot. Fennici 20: 31-40. KOPONEN, T., A. Touw & D. H. NORRIs 1986. Bryophyte flora of the Huon Peninsula, Papua New Guinea. XIV. Rhizogoniaceae (Musci). Acta Bot. Fennica 133: 1- 24. MA NUEL, M. G . 1980. Miscellanea bryologica 11. Classification of Rhizogonium Brid., Penzigiella hookeri Gangulee, and some nomina nuda. Crypt. Bryol. Lichenol. 1: 67-72. NORRIS, D . H . & H. ROBINSON 1979. The systematic position of Bryobrothera crenulata. Bryologist 82 : 305-309. SAINSBURY, G . O. K . 1955. A handbook of the New Zealand mosses. Bull. R. Soc. New Zealand 5 : 1-490. SHAW, J. & L. E. ANDERSON 1986. Morphology and homology of the peristome teeth in Hymenodon and Hymenodontopsis (Rhizogoniaceae: Musci). Syst. Bot. 11: 446-454. STONE, I. G . 1983. A re-evaluation of the species of Mesochaete Lindb. (Rhizogoniaceae). J. Bryo\. 12 : 35\-357.