Alophosia

  • Authority

    Smith, Gary L. 1971. Conspectus of the genera of Polytrichaceae. Mem. New York Bot. Gard. 21: 1-83.

  • Family

    Polytrichaceae

  • Scientific Name

    Alophosia

  • Discussion

    Fig. 26, 85, 91-93.

    Holotype: Lyellia azorica Renauld & Cardot, Bull. Soc. Bot. Belg. 38(1): 16. 1899.

    Lyellia subg Alophos Ren. & Card., Bull. Soc. Bot. Belg. 38(1): 17. 1899.

    Alophosia azorica (Ren. & Card.) Card, is known only from Madeira (Luisier, 1939) and the Azores (Fig. 90). The disc surrounding the capsule mouth, the shape and symmetry of the capsule, and the bistratose leaf lamina relate it to Lyellia, although Alophosia lacks lamellae, and has a densely hairy calyptra.

    Allorge (1949) first detected the "propagules" of Alophosia, which are borne in what appear at first glance to be perigonia. These extraordinary sti-uctures, more properly called "Brutkorper" (brood-bodies), after the terminology of Correns (1899), are 350-450 p broad, with slender hyaline stalks (Fig. 91). The internal tissue consists of large, thin-walled cells, filled with oil, surrounded by a distinct epidermal layer of thick-walled cells. The surface of the brood-body is covered with papillae.

    The brood-bodies of Alophosia superficially resemble those of Oedipodium griffi.thianum (Dicks.) Schwaegr. and Tetraphis pellucida Hedw., but are nearly twice as large. The brood-bodies of Alophosia are not intermingled with antheridia as in Oedipodium. Like those of Oedipodium, the brood-bodies of Alophosia have superficial "Vegetationspunkten" (Fig. 92), usually in ]iairs, one above the other, on the margins. Occasionally these occur on the broad faces as well. The broodbodies break off at the junction with the stalk, leaA'ing clusters of stalks which might be mistaken for extremely long-necked archegonia. Germinating broodbodies give rise directly to leafy stems (Fig. 93).

    The brood-bodies of Alophosia seemingly lend sujiport to the view that Tetraphis (Georgia) may be allied to the Polytrichaceae. Still, Alophosia is scarcely i'cpresentative of the Polytrichaceae, and its brood-bodies more closely resemble those of Oedipodium. One can not rule out the possibility that broodbodies originated independently in this isolated insular endemic.

    The present flora of the Macaronesian islands includes several species of higher plants which grew in continental Europe in preglacial times. As with the gymnospermous and angiospermous Pliocene floras, the Pleistocene ice advances must also have caused the disappearance of numerous species of mosses from the European scene. It seems likely, as Herzog (1926) suggested, that Alophosia represents an ancient type which was formerly more widely distributed, now persisting in isolation in the Azores and Madeira. The absence of lamellae in Alophosia is the ultimate expression of a trend already apparent in Lyellia, but Alophosia retains the more primitive calyptra.