A new species in the tree genus Polyceratocarpus (Annonaceae) from the Udzungwa Mountains of Tanzania.

Andrew R Marshall,Nicolas J Deere,W.R Quentin Luke,Henry J Ndangalasi,Abigail L Summers,Sue Sparrow,David M Johnson,Thomas L.P Couvreur

doi:10.3897/phytokeys.63.6262

Andrew R Marshall, Nicolas J Deere + Show 6 more

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https://doi.org/10.3897/phytokeys.63.6262

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Abstract

Polyceratocarpus askhambryan-iringae, an endemic tree species of Annonaceae from the Udzungwa Mountains of Tanzania, is described and illustrated. The new species is identified as a member of the genus Polyceratocarpus by the combination of staminate and bisexual flowers, axillary inflorescences, subequal outer and inner petals, and multi-seeded monocarps with pitted seeds. From Polyceratocarpus scheffleri, with which it has previously been confused, it differs in the longer pedicels, smaller and thinner petals, shorter bracts, and by generally smaller, less curved monocarps that have a clear stipe and usually have fewer seeds. Because Polyceratocarpus askhambryan-iringae has a restricted extent of occurrence, area of occupancy, and ongoing degradation of its forest habitat, we recommend classification of it as Endangered (EN) on the IUCN Red List.

Highlights

The Eastern Arc Mountains of Kenya and Tanzania are well known for their high levels of biodiversity and endemism across many plant and animal groups (Lovett and Wasser 1993, Myers et al 2000, Newmark 2002, Burgess et al 2007, Dawson and Gereau 2010)
The only other species with such a high number of carpels (18 to 20) is Polyceratocarpus laurifolius Paiva from northern Angola, but that species differs from P. askhambryan-iringae in having densely pubescent twigs, a distinctly cuneate base to the leaf, a larger bract on the pedicel, and larger sepals
Polyceratocarpus laurifolius differs from P. askhambryan-iringae in having larger petals of the staminate flowers than of the bisexual ones (Paiva 1966); in P. askhambryan-iringae no petal dimorphism between staminate and bisexual flowers was seen

Summary

Introduction

The Eastern Arc Mountains of Kenya and Tanzania are well known for their high levels of biodiversity and endemism across many plant and animal groups (Lovett and Wasser 1993, Myers et al 2000, Newmark 2002, Burgess et al 2007, Dawson and Gereau 2010). Marshall 2117 (holotype K; isotypes DSM, MO, NHT), Tanzania, Iringa Region: Ndundulu Forest, Kilombero Nature Reserve, Udzungwa Mountains, 07°48'S, 36°31'E (WGS84), 1490 m, 30 May 2011.

Results

Conclusion