Etymology:
Honouring Australian botanist Dr L.A.S. Johnson (192?- 1997), Director of the Royal Botanic Gardens Sydney (1972-1985) and notable student of Macrozamia in the 1950's.
Historical notes: Regarded for many years as merely an interestingly disjunct outlying occurrence of the closely related M. moorei, until recognised as distinct by Australian botanists David Jones and Ken Hill in 1991. Distinguishing features: Closely allied to M. moorei, sharing the broad, spiny petioles, but separated by the flat, glossy leaves and shorter stature. Distribution and habitat: Known only from a small area in the Dalmorton district in northern coastal N.S.W. Locally abundant in wet to dry sclerophyll forest, on shallow, rocky, usually steeply sloping and poor soils. Occasionally cultivated as an ornamental. Conservation status: Not considered to be at risk, although restricted in distribution (IUCN Red List category LR,lc; ROTAP category 2R-). 1997 IUCN Red List of Threatened Plants category R.
Description:
Plants arborescent, stem 0.3-3 m tall, 50-90 cm diam. Leaves 70-120 in crown, bright green, highly glossy, 150-300 cm long, flat (not keeled) in section, with 150-250 leaflets; rachis not spirally twisted, straight, lax and pendulous; petiole 2-8 cm long, straight, spinescent, 25-28 mm wide at lowest leaflets; basal leaflets reducing to spines. Leaflets simple, weakly discolorous; margins flat; apex entire, spinescent; median leaflets 200-400 mm long, 5-11 mm wide. Pollen cones fusiform, 25-40 cm long, 8-10 cm diam.; microsporophyll lamina 18-30 mm long, 12-18 mm wide; apical spine 2-50 mm long. Seed cones ovoid, 35-65 cm long, 13-18 cm diam.; megasporophyll lamina 50-70 mm long, stipe 50-70 mm long, megasporophyll with an expanded peltate apex 40-60 mm wide, 20-30 mm high; apical spine 5-50 mm long. Seeds flattened-ovoid, 40-55 mm long, 25-30 mm wide; sarcotesta red.
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