Vol. 45 TORREYA September 1945 



The Taxonomy of the Genus Krukoviella A. G. Smith (Ochnaceae) 



John D. Dwyer 



The history of the genus Krukoviella A. C. Smith, while recent, is rather 

 complex. In 1904 van Tieghem (Ann. Sci. Nat. Paris VIII, 19: 39) published 

 the genus Planchonella with one species P. disticha in his family Luxem- 

 bourgiacees. Obviously lie was unaware that his genus was a homonyn of the 

 earlier Planchonella Pierre of the Sapotaceae (Notes Botaniques Sapotacees 

 1-36. 1890). Ule in 1915 (Notizbl. Bot. Gart. Berlin 6: 340) made a new com- 

 bination of van Tieghem's species Godoya disticha (van Tieghem) Ule. A. C. 

 Smith without reference to any of this earlier work published the genus 

 Krukoviella (Jour. Arnold Arb. 20: 295. 1939) with one species K. scandens. 

 Thus Krukoviella A. C. Smith takes precedence over the invalid homonym 

 Planchonella van Tieghem, the type species of Krukoviella being Planchonella 

 disticha van Tieghem. In this paper I have made the new combination : Kruko- 

 viella disticha (van Tieghem) Dwyer. 1 



While the nomenclatural history of Krukoviella is complex, its phylogenetic 

 position is relatively simple. Its relationship with several tropical American 

 genera of the tribe Luxemburgieae : Godoya R. and P., Cespedesia Goudot, and 

 Rhytidanthera van Tieghem, is evident, being manifest especially in its foliar 

 bracts which bear basal glandular appendages on the inside. In contrast to this 

 complex of genera Krukoviella lack's similar appendages on the inner face of 

 the sepals, a condition furnishing an excellent generic character. Its close 

 relationship with Godoya R. and P. is shown principally in the morphology, 

 venation, and texture of the leaf-blades, in the texture and shape of the sepals, 

 and in the dehiscence of the anthers by a single instead of by two terminal 

 pores. While A. C. Smith gives an excellent discussion of the genus I must 

 disagree with his statement that Krukoviella differs from the remaining genera 

 of the tribe in the character of its stigmas. Although dissections of immature 

 pistils of Cespedesia, Godoya, and Rhytidanthera show them to have little 

 stigmatic differentiation, mature material reveals that these genera possess 

 definite sessile radiating stigmas similar to those of Krukoviella. Likewise I 

 cannot agree with Smith's statement that Krukoviella differs from Godoya in 

 that the stamens are disposed about the pistil in one row rather than two. 

 Observations have revealed that both genera have their stamens arranged in a 



1 This paper was submitted as part of a thesis on the American Genera of the Tribe 

 Luxemburgieae (Ochnaceae), in partial fulfillment of the requirements for the degree of 

 Doctor of Philosophy, Biological Laboratories, Fordham University Graduate School, New 

 York, N. Y. 



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