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| Photo Ken Hill
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| The Cycad Pages
| | Cycas scratchleyana
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- Cycas scratchleyana F. Muell., Victorian Naturalist 2(2): 18-19 (1885). H—MEL
- TYPE: New Guinea, Mt. Bedford, Jala River, Dedouri-Country, W. Armit s.n. (holo MEL; iso K).
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| Photo Gary James
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Etymology:
Honouring English military engineer and colonial administrator
Sir Peter Henry Scratchley (135-1885), Special Commissioner for
the Territory of New Guinea from 1884-1885.
Literature:
White 1922 (as circinalis).
Illustrations:
Schuster 1932,
Hill 1994b, fig. 13.
Historical notes:
Described in 1885 by German-born but pre-eminent Australian colonial botanist
Sir Ferdinand Jacob Heinrich von Mueller (1825-1896).
Collection details cited were "On Mount Bedford, Jala-River,
Dedouri-Country; W. Armit." The single specimen known, which
can be accepted as the holotype, is MEL 68059 (photo NSW), collected
by W.E. Armit on the Argus Expedition into the hinterland of Port
Moresby in 1883. The label reads as cited by Mueller, without
the "On" preface, although Mount Bedford and Jala River
were treated as separate localities by Mueller in a listing of
Armit collections appended to the protologue. The label was also
written entirely in Mueller's hand. Schuster cited "Mount
Bedford, Jala-River (Rev. James Chalmers in Herb. Sidney); Dedouri-Country
(W. Armit in Herb. Sidney)." None of these specimens can
be found in NSW. An isotype, sent by Mueller, is held by K.
This species has been poorly understood since it was first described.
Subsequent authors have generally ignored the name C. scratchleyana,
most commonly using the name C. circinalis
(Lauterbach 1901;
White 1922).
The most recent treatment by Schuster (op cit.)
regarded C. scratchleyana as a variety of C. circinalis
within subspecies papuana, effectively combining three
subsections of section Cycas in a single species.
Schuster's treatment has not been generally followed, although
attempts to follow it in the Pacific were made by
Smith (1979)
and Kanehira (1938).
More recently, there has been a tendency
to apply the names C. rumphii, C. circinalis and,
to a lesser extent, C. media somewhat uncritically, including
to specimens of C. scratchleyana
(Paijmans 1976;
specimen determinations in LAE, CANB, L, BO).
Distinguishing features:
Distinguished by the relatively large, ovate megasporophyll lamina
with numerous short to medium-length lateral spines, the long,
narrow, thin leaflets that lack hypodermis and are frequently very
strongly undulate, and the usually wholly spinescent petiole.
Adaxial mesophyll is continuous across the usually narrow and
strongly raised midrib, and abaxial mesophyll also is sometimes
continuous. Some specimens display broader, harder leaflets with
scattered laminar hypodermis, possibly as an environmental response to
higher light conditions.
Some specimens from around Port Moresby also show somewhat narrower,
harder and slightly keeled leaflets with a harder and glossier cuticle,
and are interpreted as the products of hybridism with C. campestris.
Distribution and habitat:
Widespread in eastern New Guinea, extending from near-coastal
sites to foothills, from Milne Bay west to southern and western Irian
Jaya, apparently mainly on the southern catchments.
Also known from Ambon and other Moluccan islands. This species also overlaps the geographic range
of C. rumphii in the west of the range. C. rumphii is, however, a primarily
littoral species, whereas C. scratchleyana is a forest species.
Sporadic and scattered, in more or less closed mesophyll forest
in wet lowland areas, on ridges. Often extending to higher elevations (to over 900
m), usually on slopes or ridges in more or less closed, moist
forests, but also extending to similar forests on stabilised calcareous
coral-sand dune country and nearby headlands, particularly in
the east of the range.
Vernacular:
Enge-Enge (Mekeo language, Maipa village), Notuweh
(Medino village), Kataki (Dsimakani language, Lake Murray district).
Conservation status:
Widespread and not under immediate threat of extinction.
IUCN (1994)
Red List status LR nt.
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| Photo Ken Hill
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Description:
Stems arborescent, to 4(-7) m tall, 12-20 cm diam. at narrowest point.
Leaves bright green or deep green, highly glossy, 170-310 cm long, flat (not keeled) in section (opposing leaflets inserted at 180° on rachis), with 160-300 leaflets, with white tomentum shedding as leaf expands; rachis usually terminated by a spine or paired leaflets. Petiole 25-70 cm long (20-30% of total leaf), petiole glabrous, spinescent for 80-100% of length. Basal leaflets not gradually reducing to spines.
Median leaflets simple, strongly discolorous, 220-310 mm long, 10-16 mm wide, inserted at 60° to rachis, decurrent for 1 mm, narrowed to 2.5 mm at base (to 20% of maximum width), 16 mm apart on rachis; median leaflets section flat; margins slightly recurved and undulate; apex softly acuminate, not spinescent; midrib raised above, raised below.
Cataphylls linear, pungent, pilose, 50-100 mm long, articulated.
Pollen cones narrowly ovoid or fusiform, yellow to brown (pale), 20-25 cm long, 10-13 cm diam.; microsporophyll lamina firm, not dorsiventrally thickened, 35 mm long, 20 mm wide, fertile zone 27 mm long, sterile apex 6 mm long, raised, apical spine prominent or rudimentary, sharply upturned, 2-6 mm long.
Megasporophylls 28 cm long; ovules 2-8, glabrous; lamina ovate to lanceolate, 45-80 mm long, 38-50 mm wide, regularly dentate, with 28-40 soft lateral spines 5-8 mm long, 1 mm wide, apical spine distinct from lateral spines, 25-30 mm long, 3 mm wide at base.
Seeds flattened-ovoid, 43-55 mm long, 32-40 mm wide; sarcotesta orange or orange-brown, not pruinose, 5-7 mm thick; fibrous layer present; sclerotesta smooth. Spongy endocarp absent.