A revision of infrageneric classification in Astelia Banks & Sol. ex R. Br. (Asteliaceae)
Author
Birch, Joanne L.
Department of Botany, University of Hawaii at Manoa, Honolulu, HI, 96822, USA & Present address: Royal Botanic Gardens Victoria, Birdwood Avenue, Melbourne, Victoria 3004, Australia
joanne.birch@rbg.vic.gov.au
text
PhytoKeys
2015
2015-07-13
52
105
132
http://dx.doi.org/10.3897/phytokeys.52.4768
journal article
http://dx.doi.org/10.3897/phytokeys.52.4768
1314-2003-52-105
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Astelia sect. Micrastelia Skottsb.
Astelia sect. Micrastelia
Skottsb., Kongl. Svenska Vetenskapsakad. Handl. ser. 3, 14(2): 56. 1934.
Note.
Low, compact, turf forming growth form; leaves caniculate; inflorescence bearing few flowers; staminate flowers with short filaments (0.6-1.9 mm); pistillate flowers with short outer tepals (2.6-3.8
x
0.8-1.3 mm); ovary trilocular, intermediate length (2.6-3.8 mm); fruit ellipsoid, many seeds per fruit (17-24); seeds short and narrow (1.1-1.7
x
0.5-0.8 mm). Type:
Astelia pumila
(Forst.) Gaudich.
Remarks.
The relationships of
Astelia sect. Micrastelia
are poorly resolved, with alternate relationships with
Astelia subg. Asteliopsis
and the clade containing
Astelia subg. Tricella
and
Collospermum
(Birch unpublished PhD thesis 2011,
Birch et al. 2012
).
Astelia sect. Microastelia
contains a single species,
Astelia pumila
, which is a compact, turf-forming plant and dominant component of
Astelia
moorland in Chile, the Falkland Islands, and Tierra del Fuego. As a cushion-forming species, it differs morphologically from
Astelia subg. Asteliopsis
, which contains species with open, spreading growth form that are epiphytic or terrestrial and primarily found of the understory in lowland to montane forests.
Astelia pumila
does share morphological features with
Astelia subg. Asteliopsis
(e.g. short pistillode or pistil) and, alternatively, with
Astelia subg. Collospermum
and
Astelia subg. Tricella
(e.g. seeds with a short, truncate funicle). The subgeneric placement of
Astelia sect. Micrastelia
remains equivocal and the section is unplaced (
incertae sedis
).
Included species and distribution.
Chile, Falkland Islands, Tierra del Fuego:
Astelia pumila
(Forst.) Gaudich.
Habitat.
Lowland (low latitudes) to sub-alpine (mid and higher latitudes) herbfields particularly on wet substrates (seeps, swamps etc.).