Jackiella curvata Allison & E.A.Hodgs.
Holotype: New Zealand, North Is., Ngongotaha Mtn., ca. 2000 ft., Rotorua, Allison (MPN, Hodgson hb. no. 6386, non vidi).
Plants closely creeping, but when crowded in moist sites may become erect, light green in shade phases, but in exposed sites often fuscous or chocolate-brown, at times with a somewhat scorched appearance. Leaves often subvertical, dorsally assurgent, often suberect, less often obliquely spreading and then with a Leptoscyphus -like facies in dorsal aspect, with insertion lines not extending to stem midline dorsally, delimiting a leaf-free strip of 1–2 cells wide, the leaves imbricate, broadly ovate-triangular to suboblate, broad-based, rather ampliate at ventral base, 600–900 µm wide × 600–800 µm long, about as wide as long. Cells in median leaf large, 28–36(38) µm wide, subisodiametric, usually hexagonal, with coarse, nodose-triangular trigones, the middle lamella distinct and deep brown. Oil-bodies dull opaque, grey to very pale brown, in median cells normally 2 per cell, sporadically 3 per cell, rarely 1 per cell, at times 2–3(5) per median cell, finely granular, the spherules not protruding beyond membrane, the oil-bodies globose to narrowly to broadly elliptic, less often linear to weakly crescentic, conspicuously large, 7.8–8.8 × 10.7–13.7 µm to 8.8–10.7 × 22.4–23.4 µm.
Underleaves absent or vestigial, at times connate on one side, lamella-like to irregularly short-ciliate. Gemmae frequently present, in masses at the ± attenuate shoot tips, brownish green to reddish brown, ellipsoidal, 2-celled, 13–17 × 20–25 µm.
Sporophyte as in family description.
Distribution and Ecology : New Zealand: South Island (ca. 100–200 m), North Island (365–650 m); Australia: Tasmania, Victoria. Known in New Zealand from Westland, Southern North Island, Volcanic Plateau, Auckland and Northland EPs.
In the South Island known only from scattered sites. It occurs, for example, near Hercules Creek (Mt. Hercules Scenic Reserve, south Westland, ca. 100 m) and on road banks above the Tiropahi River (north Westland, 200 m). It is widespread in the North Island (and often abundant northward), commonly in disturbed sites, such as exposed soil of roadside banks and soil between rocks in road cuts. The species grows on compact mineral soils and occurs in thin, at times rather large, mats or as scattered small patches. Also on vertical clayey banks, at times associated with Blechnum, or over exposed, soil-covered rock walls such as in scrub forests of Leptospermum scoparium, Weinmannia silvicola and Dacrydium cupressinum (ridge between Webb Creek Track and Billy Goat Track, Coromandel Forest Park). These are warm, sunny sites, often without other accompanying hepatics, and in these niches plants are able to tolerate desiccation; in exposed sites plants are typically fuscous or chocolate-brown. The species occasionally grows on well-shaded banks, and in such cases plants are light green. In more mesic sites, sometimes associated with Isotachis, chiefly I. lyallii, but also I. montana, Baeomyces heteromorphus, Campylopodium medium, Ditrichum difficile, Lycopodium scariosum, Polytrichadelphus magellanicus, Riccardia crassa and Stereocaulon ramulosum. One collection was made from the base of a Leptospermum scoparium trunk, where the Jackiella was growing with Cuspidatula monodon, Frullania aterrima, Hypnum cupressiforme, Macromitrium gracile and Thuidium furfurosum.
Comments : See under the genus. Among the few closely creeping hepatics in New Zealand with strongly succubous, unlobed leaves (Fig. 137: 2), Jackiella curvata may be confused only with some Solenostoma species, which are comparable in aspect and size and which may occur on similar (but usually more mesic) roadside habitats and banks. Moreover, the collenchymatous cells each with 2–3 large oil-bodies (Fig. 137: 6) also may occur in Solenostoma. However, the chocolate-brown to deep brown color of the plants, without a trace of reddish pigmentation typical of Solenostoma, will immediately separate J. curvata from any other regional taxon. Jackiella is immediately distinct in rhizoid position: only in fascicles from the bases of vestigial underleaves (Fig. 137: 2) or, if rhizoids are absent, rounded convexities or small cushions that represent rhizoid-initials may be distinguishable. Also, branching in Jackiella is purely intercalary (Fig. 137: 3).
