Metzgeria
Epiphytic, epiphyllous, on logs, occasionally lithophytic or rarely terrestrial, monoicous or dioicous. Asexual reproduction by discoid to elliptic or oblong gemmae produced on thallus margins or adaxial thallus surface. Plant comprising a repetitively dichotomous or irregularly bipinnate (not in Victoria) thallus, sometimes also branching from abaxial midrib, with distinct midrib and wings; branches linear or narrowly lingulate; wings pale green, yellowish green or olive green, often abaxially and rarely adaxially with hairs; wing margins entire, rarely with inrolled and inflated sac-like lobes, often with solitary or paired hairs; wings cells unistratose, polygonal, smooth or rarely papillose (not in Victoria), thin- to thick-walled, uniform throughout. Antheridia concealed in sac-like, reduced, circinate, hairy or glabrous abaxial branch with incurved lateral margins. Sporophyte produced on adaxial surface, near base of short, flattened obcordate to obovate abaxial branch; coelocaule hairy or with dentate scales. Capsule ovoid to obloid or globose, bistratose, dehiscing by 4 valves; elaters present, unispiral. Spores smooth or finely granulate, yellow, brown or reddish-brown.
103 species throughout the world except Antarctica, with highest diversity in tropical South America (Söderström et al. 2016); five species in Victoria.
Söderström, L., Hagborg, A., von Konrat, M., Bartholomew-Began, S., Bell, D., Briscoe, L., Brown, E., Cargill, D.C., Costa, D.P., Crandall-Stotler, B.J., Cooper, E.D., Dauphin, G., Engel, J.J., Feldberg, K., Glenny, D., Gradstein, S.R., He, X., Heinrichs, J., Hentschel, J., Ilkiu-Borges, A.L., Katagiri, T., Konstantinova, N.A., Larraín, J., Long, D.G., Nebel, M., Pócs, T., Puche, F., Reiner-Drehwald, E., Renner, M.A.M., Sass-Gyarmati, A., Schäfer-Verwimp, A., Moragues, J.S., Stotler, R.E., Sukkharak, P., Thiers, B.M., Uribe, J., Váňa, J., Villarreal, J.C., Wigginton, M., Zhang, L. & Zhu, R. (2016). World checklist of hornworts and liverworts. Phytokeys 59: 1–828.
Spinning