A MONOGRAPHIC REVISION OF RETROPHYLLUM (PODOCARPACEAE)

R R Mill

doi:10.1017/s0960428616000081

Abstract

The living species of the genus Retrophyllum C.N. Page (Podocarpaceae) are revised. A key to the six species recognised is given. Retrophyllum filicifolium (N.E.Gray) R.R.Mill comb. nov. from New Guinea and the Moluccas is recognised as a species distinct from R. vitiense (Seemann) C.N. Page, which is restricted to material from Fiji and the Solomon Islands. Additional characters are given by which to separate Retrophyllum piresii (Silba) C.N. Page (Brazil) from R. rospigliosii (Pilg.) C.N. Page (Andes). The six species fall into three species-pairs that differ in reproductive characters: one pair in Papuasia and Melanesia, a second on New Caledonia and a third in South America. In the New Caledonian species-pair, the adult leaves are flattened in four ranks with only minimal heterofacial twisting, whereas in the species-pair inhabiting Fiji, New Guinea and neighbouring areas, as well as the pair inhabiting South America, the adult leaves are arranged in two ranks with significant heterofacial twisting. The names Podocarpus filicifolius N.E.Gray and Nageia minor Carrière, respectively the basionyms of Retrophyllum filicifolium and R. minus, are lectotypified, and the typification of Nageia minor comprehensively discussed in an appendix. Adult female epitypes are additionally designated for Podocarpus filicifolius, which was originally based on juvenile foliage of Retrophyllum mixed with a detached seed of Nageia wallichiana, and for Nageia minor, which Carrière described on the basis of sterile material. Two other appendices provide a list of accepted names and synonyms, and a list of exsiccatae. Illustrations and distribution maps are provided for each species.

Highlights

Sheet P00188111 comprises material collected at three different localities by two different collectors, and the earliest-mounted appears to have been the Deplanche specimen, whereas Carrière only cited Vieillard as collector and lac Arnaud as locality
Polypodiopsis C.E.Bertr. for two species that were known as Podocarpus vitiensis Seem. and P. minor (Carrière) Parl
De Laubenfels (1972) cites a female specimen of Retrophyllum minus at P collected by Pancher in 1864 at Prony, which is on Baie du Sud

Summary

Introduction

Sheet P00188111 comprises material collected at three different localities by two different collectors, and the earliest-mounted appears to have been the Deplanche specimen, whereas Carrière only cited Vieillard as collector and lac Arnaud as locality. They, and similar sterile specimens (109-F, 110-D, 111-A, 111-C, 111-F, 111-G and 111-H), are all considered unsafe for lectotypification purposes, partly because Vieillard may not have collected them and partly because Carrière could not have seen either gathering numbered Deplanche 170, as discussed later.

Results

Conclusion