logo
The Cycad Pages
Cycas aenigma

Cycas aenigma K.D.Hill & A.Lindstr., Telopea 12(1):130–132. fig. 3 (2008). H—LBC
"TYPE: Philippines, Palawan, cult. Puerto Princessa city, Fernando 1617, 26 Jun 2001 (holo LBC)."


Etymology: From the Latin aenigma, to speak darkly, the root of the Engish word enigma, a thing which cannot be satisfactorily explained; a puzzle; a reference to our knowledge of this particularly distinctive species only as a cultivated plant.

Historical notes: This singular and distinctive species was not recognised as new until 2001, in cultivation in Puerto Princessa City, and remained undescribed until 2008.

Distinguishing features: It is distinguished from all other species in the region by the robust pollen cones with stout, spreading apical spines on microsporophylls and the open seed cones with long megasporophylls and very long attenuate megasporophyll apices with long slender lateral spines. The stout, spreading spines resemble those seen in C. circinalis and allies from peninsular India and C. pranburiensis from Thailand, but none of these species show the green colour in the male cone or the long-attenuate megasporophyll. It is however, grouped with these species in subsection Cycas on the basis of the shared microsporophyll character.

Distribution and habitat: Not known. This species is known only in cultivation in Puerto Princessa City on Palawan Island. It is not known if the plants originated on that island, but this seems probable.

Conservation status: Unknown. IUCN (2001) Red List status DD.

Description:

Stems arborescent, to 0.5–4 m tall.

Leaves bright green, highly glossy, 200–290 cm long, flat (not keeled) in section (opposing leaflets inserted at 180° on rachis), with 300–380 leaflets, tomentum shedding as leaf expands; rachis consistently terminated by paired leaflets; petiole 40–60 cm long (15–20% of total leaf), glabrous, spinescent for 90–100% of length; basal leaflets not gradually reducing to spines, 220–230 mm long.

Median leaflets simple, strongly discolorous, 300–340 mm long, 10–13 mm wide, inserted at 60–75#176; to rachis, decurrent for 3–5 mm, narrowed to 2.5–3 mm at base (to 20–30% of maximum width), 10–12 mm apart on rachis; section flat; margins flat or slightly recurved, not undulate; apex acute, not spinescent; midrib raised above, raised below, narrow.

Cataphylls narrowly triangular, soft, pilose, 70–100 mm long.

Pollen cones ovoid, green or cream, c. 34 cm long, c. 16 cm diam.; microsporophyll lamina firm, not dorsiventrally thickened, c. 80 mm long, c. 25 mm wide; fertile zone c. 29 mm long, level; apical spine prominent, gradually raised (spreading), c. 47 mm long.

Megasporophylls 36–40 cm long, brown-tomentose, tomentum shedding; ovules 4–6, glabrous; lamina lanceolate, 220–240 mm long, 35–40 mm wide, deeply pectinate or shallowly pectinate, with 24–34 pungent lateral spines 16–25 mm long, 3–4 mm wide; apical spine distinct from lateral spines,110–140 mm long, 6–7 mm wide at base. Seeds not observed.


The Cycad Pages

© 1998-2012 Royal Botanic Gardens Sydney
Written and maintained by Ken Hill 1998-2010
Maintained by Leonie Stanberg and Dennis Stevenson 2010-2012
This site is currently not being maintained