Blechnum acanthopodum
Content
Distribution
Asia-Tropical, D’Entrecasteaux Islands off the north-east coast of Papua present, Goodenough Island present
Malesia: Blechnum acanthopodum is known at present from a single collection from Goodenough Island (a high island) in the D’Entrecasteaux Islands off the north-east coast of Papua.
Notes
1. The specific epithet refers to the spine-like structures on the stipe and the base of the rhachis.
2. The general morphology suggests that this taxon is related to B. whelanii where the presence of minute woody outgrowths along the adaxial ridges may be evidence of structures related to the conspicuous spine-like ‘aerophores’ of B. acanthopodum.
3. Blechnum acanthopodum resembles B. whelanii in lacking auricles down the base of the rhachis, but is significantly larger and has numerous pinnae (c. 42 pairs) and prominent woody ‘aerophores’ at 2-3 cm intervals along the stipe, on either side of the groove on the adaxial or upper surface. The fertile pinnae are 25 by 0.8-0.9 cm, widening slightly near the rhachis and becoming somewhat cordate and shortly petiolate.
2. The general morphology suggests that this taxon is related to B. whelanii where the presence of minute woody outgrowths along the adaxial ridges may be evidence of structures related to the conspicuous spine-like ‘aerophores’ of B. acanthopodum.
3. Blechnum acanthopodum resembles B. whelanii in lacking auricles down the base of the rhachis, but is significantly larger and has numerous pinnae (c. 42 pairs) and prominent woody ‘aerophores’ at 2-3 cm intervals along the stipe, on either side of the groove on the adaxial or upper surface. The fertile pinnae are 25 by 0.8-0.9 cm, widening slightly near the rhachis and becoming somewhat cordate and shortly petiolate.