Ecogeography and taxonomy of Rogeria J. Gay ex Delile (Pedaliaceae)

Abstract

Presented here are an extensive revision of Rogeria J. Gay ex Delile, a key to its three accepted species, a description of a new species, Rogeria armeniaca Bedigian from the Kunene region of Namibia and Angola, and a description of a new subspecies, Rogeria adenophylla subsp. rosea Bedigian, in Namibia and Angola. Specimens of the new species and subspecies were until now included in the polymorphic Rogeria adenophylla J. Gay ex Delile. Morphology and preliminary molecular study of the genus Rogeria supports the recognition of the new taxa. Rogeria armeniaca is identifed by its distinctive apricot-coloured flowers, and glossy, elongate, deeply lobed leaves with sharply pointed, acute apices. Subsp. rosea is distinguished by its bright rose-pink corolla with a golden yellow interior, and broadly deltoid or lobed, pubescent leaves with truncate apices. Morphological traits allowing Rogeria to survive in hot, arid environments include mucilage-bearing glandular trichomes and persistent woody capsules that decompose slowly.

Keywords:

• Angola
• arid
• disjunction
• indumenta
• Kaokoland
• Namibia
• Pedaliaceae
• Rogeria
• serotiny
• Sudan

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Corrigendum

Acknowledgements

I am indebted to many for their encouragement of this review. Permission to do research in Namibia was granted by the Ministry of Environment and Tourism, and in Sudan by Sudan’s Agricultural Research Corporation headquarters at Wad Medani and area offices at El Fasher, El Obeid and Nyala; additional authorization was offered by the Ministry of Agriculture, Khartoum and Gedaref. A.R.M. Tahir, director of Sudan’s Nyala agricultural research station, offered immeasurable logistical support under complicated conditions. Individuals at numerous institutions in both countries offered superb encouragement and hospitality, their actions serving as valuable examples in similar instances.

I am grateful to Missouri Botanical Garden herbarium curator J.C. Solomon, who obtained specimen loans C. Solomon, who obtained specimen loans and offered suggestions for this study, part of ongoing research about biogeography and systematics in Pedaliaceae, and to each herbarium curator, thanked wholeheartedly for access to their specimens. K. Neubig (FLAS) contributed the molecular analysis; B. Bassüner (MO) produced a series of distribution maps; D. Austin (ASDM), P. Goldblatt (MO), G. McPherson (MO), C. Mannheimer (WIND), and S. Smithies (PRE), provided valuable critiques of the manuscript; M. Duncan, Wright State University, Dayton OH prepared seed photographs; S. Smithies (PRE) offered a handwritten note by J. Abels (HBG), stored in a cupboard with Rogeria specimens at PRE; floral images by N. Jürgens (HBG), C. Mannheimer (WIND), J.C. Manning (NBG), T. Musch (University Bayreuth/Germany).

Fieldwork and herbarium study received partial support from the Crop Evolution Laboratory, University of Illinois Urbana-Champaign (1979–1980), and from National Geographic Society Research and Exploration grants #6218-98 and #7732-04. Publication no. 128 of the Centro Studi Erbario Tropicale of the University of Florence (FT herbarium).