Schlumbergera kautskyi (Horobin & MeMillan) N.P. Taylor in Bradleya 9: 90 (1991).
Flowering period in Northern Hemisphere Oct to Nov
DISTRIBUTION. Brazil (S Espirito Santo): epilithic at 900-1300 m altitude.Municipio Domingos Martins, Pico da Pedra Azul, also in the Municipios of Alfredo Chaves, and Sao Bento de Urania
See Taylor, in Bradleya 9 for discussion on the rationale behind the recognition of this taxon as a species.
In its sharply toothed stem-segments, angular pericarpel, small, weakly zygomorphic flowers and elongate yellowish fruits this taxon shows affinities with all three species referable to the flat-segmented 'S. truncata group' (S. truncata, S. russelliana, S. orssichiana). Nevertheless, the combination of characters shown by S. kautskyi is unique, and its inclusion in S. truncata at infraspecific rank, as favoured by Horobin & McMillan, tends to weaken the justification for recognition of more than a single species in the complex as a whole. To be consistent, it seems preferable to recognize S. kautskyi as a separate species. According to Horobin & McMillan (l.c. 1990) it is self-fertile but cannot be crossed with either S. truncata or S. orssichiana. It is known from three localities in Espirito Santo and is considerably disjunct from the nearest populations of S. truncata and S. russelliana in the state of Rio de Janeiro.