|(A) Cyrtochilum superbiens; (B) C. pastasae; (C) C. pastasae; |
(D) C. maranthum; (E) C. maranthum; (F) C. orgyale;
(G) C. divaricatum; (H) C. ioplocon.
in Szlachetko & Kolanowska,. 2020.
(photos: Luis Carlos Piña, Maria Luisa Hincapié & Marta Kolanowska)
This article is a presentation of taxonomic diversity of the orchid genus Cyrtochilum in Northwestern South America. The morphological characteristics of over 90 species occurring in northern Peru, Ecuador, Colombia and Venezuela are presented together with illustrations of their floral segments. Information about the distribution of each taxon is provided. Ten morphologically consistent groups have been delineated to facilitate identification of Cyrtochilum representatives in the studied area. Keys for determination of species within each group are provided. Seven new species of Cyrtochilum are described and one new combination is proposed.
In our opinion, the broad concept of Cyrtochilum proposed by Neubig et al. (2012) should be rejected and only pseudobulbous, 1-4-leaved plants characterised by the right angle between the lip and gynostemium, the sessile lip which is hastate, pandurate to oblong-ovate or ligulate and much smaller than tepals should be included in this genus.
The diversity of Cyrtochilum s.str. in Northwestern South America was so far poorly recognised. Noteworthy, the vegetative organs are often absent in the type material of numerous species described in the past. We believe that our work is the first in depth step to reveal the actual variation of the genus representatives in the studied area and to conduct more detailed biogeographical and molecular analyses in the future. The deficiency of comprehensive research on morphology of Cyrtochilum; and lack of identification key have resulted in common mistakes in the identification of representatives of this genus. The incorrect determination of specimens was noted in numerous herbaria (notes on herbarium labels) as well as in the previously published local floras (photos not corresponding to the species name). These errors in identification of analysed material can led to an incorrect reconstruction of the phylogeny and infrageneric relationships within Cyrtochilum and its relatives.
The taxonomic separateness of three species pairs (Cyrtochilum hastatum–C. ionodon, C. diceratum–C. englerianum and C. tetracopis–C. monachicum) requires further studies.
Dariusz L. Szlachetko and Marta Kolanowska. 2020. Towards A Taxonomic Revision of the Genus Cyrtochilum (Orchidaceae) in Northwestern South America (Northern Peru, Ecuador, Colombia, Venezuela). PeerJ. 8:e8566. DOI: 10.7717/peerj.8566