Zoopsis argentea (Hook.f. & Taylor) Gottsche, Lindenb. & Nees
Type: New Zealand, North Is., Waipawa Co., Norsewood, 1885, Colenso.
Zoopsis basilaris Colenso, Trans. & Proc. New Zealand Inst. 21: 77. 1889 (1888).
Type: New Zealand, North Is., Waipawa Co., S of Dannevirke, 1888, Colenso 1301.
Zoopsis muscosa Colenso, Trans. & Proc. New Zealand Inst. 21: 78. 1889 (1888).
Type: New Zealand, North Is., Waipawa Co., near Dannevirke, 1888, Colenso.
[Fig. 110: 2, oil-bodies, p. 486]
Plants to 825 µm wide, axis and rudimentary leaves strikingly flattened, forming a band-like thallus; axis proper, at maturity, formed dorsally of 4–5 rows of cells; ventral face of plant of up to 8–10 rows of cells; ventral side of axis with conspicuous rhizoid-initial discs at bases of rudimentary underleaves, and locally at leaf bases.
Distribution and Ecology : Endemic to New Zealand: Stewart Island (sea level), South Island (110–800 m), North Island (sea level). Known from Rakiura (Port Pegasus), Otago (Table Hill), Westland (Fox Glacier), Western Nelson (Moa Park), Southern North Island (Norsewood, Dannevirke) and Gisborne (Urewera Natl. Park) EPs. At Moa Park (N Arthur Ra., 760 m) it occurred under Nothofagus fusca forest on damp humus and was growing with Chiloscyphus echinellus, Kurzia hippuroides, Telaranea gibbsiana and Zoopsis setulosa.
Comments : This taxon exhibits an extreme expression of shoot elaboration within the genus, showing the closest approach to a thallus, with the leaf rudiments poorly set off from the “frond.” The var. flagelliformis typically has a much more elaborate, more frond-like structure than that of the typical variety. One or both of the 2 chlorophyllous leaf cells may be subdivided, so that the leaf is often formed of 3–4 chlorophyllous cells. In addition, the dorsal cortical cells are secondarily divided, so that the axis becomes 4–5 cell rows broad, rather than the 2 rows usually found in var. argentea. In ventral aspect, the ventral merophyte remains 2 cells broad, but the ventral portions of the two lateral merophytes become 3–4 cells broad, resulting in a “frond” that (leaves included) is 11–12 cells across. Such fronds may bear conspicuous, fasciculate rhizoids, forming haustorial discs, produced from the underleaf bases as well as (often) from the bases of the leaves.
