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Cephalozia pachycaulis Schust. sp. nov. is described. It occupies an anomalous position in that genus because: a) capsule walls are often largely 3-layered; b) the thickenings oftheir epidermal cells fail to show a clear two-phase development; c) the seta has up to 12 + 7-8 cell rows; d) the stem is soft, without formation of a hyalodermis. In stem anatomy it falls near Schofieldia, with which is also shared the capacity to form Frullania-type terminal lateral branches. Such branches also occur in C. bicuspidata et al. and in C. pleniceps. The wide leaves and soft texture and the free formation of unicellular gemmae at apices of short stiffbranches, invested by mutually involute, malformed, concave leaves, are further suggestive of C. pleniceps. In spite of these seeming multiple affinities, C. pachycaulis has no obvious immediate relatives. Branching patterns and the obliquely oriented concave leaves with erect lobes and an open sinus suggest that affinities are perhaps closest to C. bicuspidata. Cephalozia is usually regarded as a sharply de- fined genus, with rather precise limits. Four sub- genera (Eocephalozia Schust., Cephalozia (Du- mort.) Dumort., Haplocephalozia Schust., and Macrocephalozia Schust.) are recognized in Schus- ter (1974), of which the first, limited to cool and cold portions of the Antipodes, shows perceptible similarities to the Gondwanalandic Metahygrobiel- la Schust. Macrocephalozia is sometimes recog- nized as an autonomous genus (Fuscocephaloziopsis Fulf., 1968). Haplocephalozia, based on C. uniloba Kitagawa (1962), a plant unique in its unlobed leaves, appears to be best suppressed; the sole species seems very close to C. leucantha. The genus is regarded as apomorphic vis a vis related genera such as Cladopodiella in: a) lacking oil bodies; b) having a seta with a "fixed" anatomy, with 8 epidermal + 4 inner cell rows (Schuster 1974, p. 696, figs. 446:10, 463:6, 456:7); c) consistently |
