Mature perianths of Caudalejeunea yangambiensis (Vanden Berghen) E.W.Jones (Lejeuneaceae) are described for the first time, and the species reported new to Ghana

Wigginton, Martin J.

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41TROPICAL BRYOLOGY 19 (2000)Caudalejeunea yangambiensis from Ghana Tropical Bryology 19: 41-43, 2000Caudalejeunea yangambiensis (Vanden Berghen) E.W.Jones(Lejeuneaceae) with mature perianths from GhanaM.J. Wigginton36 Big Green, Warmington, Peterborough, PE8 6TU, United Kingdom.Abstract   Mature perianths of Caudalejeunea yangambiensis (Vanden Berghen) E.W.Jones(Lejeuneaceae) are described for the first time, and the species reported new to Ghana.Whilst examining a Ghanaian collection ofHenicodium geniculatum from P.W.Richards’West African collections (NMW), a smallaccompanying tuft of Caudalejeuneayangambiensis in one of the packets attractedattention. This species has not previously beenreported from Ghana, and this collection extendsits known distribution westwards by about 1500km. Of particular interest is that the collectionincludes mature perianths. Fertile plants of C.yangambiensis are apparently rare and, so far asI am aware, mature perianths have not beenpreviously reported. The original description ofthe species (Vanden Berghen, 1951) was basedonly on sterile plants, and in a later description(Vanden Berghen, 1978), no mention is made ofgametoecia. The only account of gametoecia areof plants from Budongo Forest, Uganda,published in Jones (1957), who described femaleinflorescences with very immature perianths,considering the species to be “probably dioicous”.Caudalejeunea yangambiensis (VandenBerghen) E.W.Jones   Lacri, Tafo: 6°13’N0°20’W, on cocoa tree in plantation, withCaudalejeunea hanningtonii, Frullaniaspongiosa and Henicodium geniculatum, 29 May1967, P.W.Richards 6317 p.p. (NMW). New toGhana.Details of latitude and longitude do not appearon the packet, and I have been unable to findcoordinates for Lacri. There are two populatedplaces named Tafo in Ghana, about 160 km apart.However, Richards published records ofbryophytes from Kibi (6°10’N 0°33’W) whichhe collected on the following day (30 May 1967),and it seems most likely that the Tafo in questionis the one near Kibi - at the coordinates givenabove.In addition to Ghana, C. yangambiensis is knownfrom a few collections from Cameroon (Jones,1990), the Republic of Congo (Pócs, 1980), D.R.42TROPICAL BRYOLOGY 19 (2000)WiggintonFig. 1. Caudalejeunea yangambiensis (Vanden Berghen) E.W.Jones  A, B: bracteoles, flattenedunder coverslip.  C: bracteole in situ.  D, E: female bracts.  F, G: perianths.  H, J, K: transversesections of a single perianth with 4 ventral keels.  Figs A-K: Richards 6317 p.p.  Scale: Figs A-K, 1.0mm.43TROPICAL BRYOLOGY 19 (2000)Caudalejeunea yangambiensis from GhanaCongo (Vanden Berghen, 1951), Rwanda(Vanden Berghen, 1978) and Uganda (Jones,1957; Pócs & Lye, 1999).The present collection is small, and consists ofparts of only four shoots, all of which lack thelower parts of the stems. However, all are fertile,with fine examples of typical gemmiferous shootswith their characteristic conduplicate leaves.Since the gametophyte has been previouslydescribed (and well illustrated in VandenBerghen, 1951), a description is given here ofonly the female structures. Only four matureperianths were available for study, one of whichwas destroyed to obtain transverse sections, andfour other perianths in various stages ofimmaturity. No male structures were present onany of the shoots.Presumed dioicous, but possibly autoicous withmale inflorescences on branches remote fromfemale structures, and not yet observed in thisspecies. Gynoecium terminal on a leading shootor lateral branch, without innovations(gemmiferous shoots, lateral). Female bracts 1.4-1.6 ´ 0.85-1.0 mm, broadly lanceolate-ovate,spreading, with entire or weakly sinuose margins,apex bluntly acute, the ventral margin sometimesinfolded; lobule small, the free margin inrolledand not visible in situ. Bracteoles 0-9-1.2 ´ 0.85-1.0 mm, very broadly obovate (as seen flattenedunder a cover-slip), but in situ the lateral marginsstrongly reflexed ventrally, and thus appearingmore oblong; apex often clearly bifid; margins ±strongly irregularly dentate to half way, sinuosebelow. Mature perianth 0.9-1.1 ´ 0.75-0.9 mm,very broadly oval, obovate or pyriform, or nearlyround, about the same length as the bracteole, orslightly immersed or exserted; weakly inflatedventrally, with usually 3-4 sharp keels, some ofwhich are at least 0.75 the length of the perianthand sometimes extending over its whole length,an additional very short ventral keel sometimespresent in the upper part of the perianth; dorsalkeel represented by a single broad, low ridge;ventral and lateral keels more or less entire, butwith an occasional prominent cell, a short andblunt tooth, or a notch, making the outline slightlyirregular; beak short, 30 µm long. No developingcapsules present.The perianths of only two of the other eightnamed species of African Caudalejeunea havetwo or more ventral keels. C. grolleana, knownonly from Madagascar, has two ventral keels,each with a rudimentary wing, but is a tiny plant,with perianths only 0.6 ´ 0.4 mm (Gradstein,1974). The perianths of C. katangensis are aboutthe same size of those of C. yangambiensis, andhave two long ventral keels with 2-3 short,supplementary ones (Vanden Berghen, 1972).The margins of the bracteoles of C. katangensisare, however, only sinuose-crisped, withoutdentition. C. madagassa (Madagascar only)sometimes has weak ventral keels, but theperianth has a broad, often interrupted, dentate-laciniate wing on the lateral keels.REFERENCESGradstein, S.R. 1974. Studies on Lejeuneaceae subf.Ptychanthoideae (Hepaticae) II.  Acta BotanicaNeerlandica 23: 333-343.Jones E.W. 1957. African Hepatics XII. Some little-known Lejeuneaceae. Transactions of theBritish Bryological Society 3: 191-207.Jones, E.W. 1990. African Hepatics XLI. Somecritical notes and new records. Journal ofBryology 16: 41-44.Pócs, T. 1980. Central African Hepaticae collectedby M. Assel. Folia Historico-Naturalia MuseiMatraensis 6: 73-81.Pócs, T. & Lye, K. 1999. New records and additionsto the hepatic flora of Uganda. 2. TropicalBryology 17: 23-33.Vanden Berghen C. 1951. Note sur trois hépatiquesdu Congo belge. Bulletin de la Société Royalede Botanique de Belgique 84: 61-64.Vanden Berghen, C. 1972. Hépatiques etAnthocérotées, in J.-J. Symoens, (ed.),Résultats scientifiques. Explorationhydrobiologique du bassin du lac Bangweoloet du Luapula. Vol. 8(1). 202pp. Bruxelles:Cercle Hydrobiologique de Bruxelles.Vanden Berghen C. 1978. Notes sur quelquesLejeuneacees holostipées africaines. RevueBryologique et Lichénologique 44: 123-132.44TROPICAL BRYOLOGY 19 (2000)Wigginton

African Hepatics XII. Some littleknown Lejeuneaceae.

African Hepatics XLI. Some critical notes and new records.

Central African Hepaticae collected by M.

Hépatiques et Anthocérotées,

New records and additions to the hepatic flora of Uganda.

Note sur trois hépatiques du Congo belge.

Notes sur quelques Lejeuneacees holostipées africaines.

Studies on Lejeuneaceae subf. Ptychanthoideae (Hepaticae) II.

Caudalejeunea yangambiensis (Vanden Berghen) E.W.Jones (Lejeuneaceae) with mature perianths from Ghana

Caudalejeunea yangambiensis (Vanden Berghen) E.W.Jones (Lejeuneaceae) with mature perianths from Ghana

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