B.1.2 Distribution of Asplenium listeriB.1.2 Distribution of Asplenium listeri

B.1.2 Distribution of Asplenium listeri

Asplenium listeri is endemic to Christmas Island (DuPuy 1993b).

Historical

The species is named for naturalist Joseph Jackson Lister, who visited in H M Survey Vessel Egeria in September-October 1887. Lister collected a specimen of the fern, probably near Flying Fish Cove towards the north-eastern corner of the island. A single specimen was reported by H N Ridley in 1906 from this same vicinity at Toms Ladder (DuPuy 1993b). There is no longer evidence for the species in this area, despite attempts to locate the type locality (Green pers. comm.).

Known

The species is now known from five localities.

Population 1 was the first locality recorded (and the only one known at the time the species was nominated for listing) at Gannet Hill, above the limestone terraces on the eastern side of the island. Because the original collections by Lister and Ridley no longer exist, the species was newly described from a single specimen collected at this locality in April 1987 (DuPuy 1993b).

Three additional localities were located during a survey of flora in March-April 2002
(Holmes & Holmes 2002):

• Population 2 - on the eastern terrace of the island on the Greta Beach Road a few kilometres south-west of the Gannet Hill locality.
• Population 3 - on the southern side of the island at Aldrich Hill approximately 9 kilometres to the west of the Greta Beach Road locality.
• Population 4 - near Sydney’s Dale (Dale No.6) on the western side of the island; about 4 kilometres west of Aldrich Hill and 13 kilometres west of Greta Beach Road/Gannet Hill.
  Note: this population was not relocated despite two attempts (Claussen pers. comm.).

These populations when combined total less than 300 individuals.

Population 5 was located in March 2003 by plant ecologists carrying out environment impact assessment for an expansion of phosphate mining. This was north of the Resort on the eastern terrace. The precise location will be provided when the draft environmental impact statement has been released, but will be kept confidential (Zimmermann; Reddell pers. comm.).

Figure 1 Localities for Asplenium listeri

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