The Malesian species of Gastonia (Araliaceae)

Only two species of Gastonia occur in Malesia, but each has a complex taxonomie history. The species which became known first, G. papuana Miq., is evidently an uncommon plant of coastal and lowland forest, but with a very wide range. It has been collected only once, or at most a few times, from each of many islands of the Malayan Archipelago and once from the mainland of the Peninsula. Most of these collections were made in the nineteenth or early twentieth centuries. Only in western New Guinea has this species been collected in more recent times within our area. The distribution of this species shows several disjunctions, the most striking being that between West Irian and its only known locality in the extreme east of the Solomon Islands. It is interesting that this gap corresponds with the distributional range of the second species, G. spectabilis (Harms) Philipson, which overlaps that of G. papuana only in the west of New Guinea (fig. 1). The widely dispersed range of G. papuana has resulted in its being described as several distinct species from different parts of its range. It was first named in 1863, when three names appeared in two genera. Miquel (1863) applied the names Tetraplasandra paucidens and Gastonia papuana to this species, and Teysmann and Binnendijk (1863) described it as Tetraplasandra eupteronoides. I am grateful to Professor van Steenis for information on the sequence of publication of these names. Miquel’s publication was issued on 2 July 1863 (Stafleu, 1967). A report in volume 27 of the ‘Natuurkundig Tijdschrift voor Nederlandsch Indië’ states that volume 25 was issued in six instalments, the first of which appeared in 1862. The five remaining parts appeared in 1863. Professor van Steenis has examined the publication and concludes that page 416, on which the name T. eupteronoides appeared, belongs to the final instalment, and must therefore have been issued late in 1863, and in any event later than July. For this reason, Miquel’s names take precedence over that of Teysmann & Binnendijk. Of Miquel’s two names, I have chosen to use that which he placed in Gastonia. In this way the need for a new combination is avoided. As can be seen from its synonymy this species was described from other islands by subsequent authors.