Pseudopanax ferox ( Kirk, 1889 )

Pole, Mike, 2022, A vanished ecosystem: Sophora microphylla (Kōwhai) dominated forest recorded in mid-late Holocene rock shelters in Central Otago, New Zealand, Palaeontologia Electronica (a 1) 25 (1), pp. 1-41 : 22

Pseudopanax ferox ( Kirk, 1889)

Figure 22

Material. Present in 4% of the shelters with dry vegetation. Shelter-001: LX2711, LX2712; Shelter-037: LX3111; Shelter-066: SL 6467; Shelter-094: LX2884.

Remarks. An intact Pseudopanax ferox leaf was found at Gibraltar Rock and Sbag 0870 (LX3111, ConcJar 2204). This, and cuticle fragments from other shelters, show the ring of subsidiary cells, and prominent outer stomatal ledges which are surrounded by a ring of thin, finely ridged cuticle, which is typical of Pseudopanax . This specimen also shows the normal epidermal cells which are much smaller than the stomatal complexes, and tangentially oriented subsidiary cells, which distinguish P. ferox from Pseudopanax crassifolious Koch (1859) . The later has much larger normal epidermal cells, and larger, more irregularly shaped subsidiary cells. P. ferox is considered to have existed in mid-late Holocene Central Otago ( Walker et al., 2004b; Rogers et al., 2005), but to date, not P. crassifolious . However, a single relict specimen of P. crassifolious is living in the Waikerikeri Valley (pers. obs.), indicating both species were likely in the region, and recognising the difference is important.

Figures

FIGURE 22. Pseudopanax leaf (reflected light) and cuticle morphology (transmitted light microscopy). A. Intact Pseudopanax ferox leaf (LX3111, Shelter-37, scale bar equals 10 mm). B. Pseudopanax ferox stomatal complexes on abaxial surface (LX2711, Shelter-1, scale bar equals 100 μm). C. Pseudopanax ferox (LX5490, Coprolite-15, scale bar equals 100 μm). D. Pseudopanax crassifolious, abaxial surface showing much larger and more irregular epidermal cells (modern reference material, OPH5338, scale bar equals 100 μm). E. Pseudopanax crassifolious, abaxial surface also showing much larger and more irregular epidermal cells (modern reference material, OPH9835, scale bar equals 100 μm).