O. chalkae was first described by Hirth and Spaeth from the Aegean island of Chalki in 2010 and is a member of the large O. oestrifera group which has been the recipient of much study and attention over the last two decades but none of which has satisfactorily clarified significant taxonomic questions, particularly as they relate to the group in the eastern Mediterranean. The distribution, status and very existence of some of the groups representatives is still subject to the differing opinions of contributors to the debate. It is further complicated by the recognition of several new species, of which O. chalkae is one.
O. chalkae is thought to be closely related to the smaller flowered Rhodian endemic, O. cornutula but which can be easily distinguished from it by the formers distinctive lip shape. O. cornutula exhibits a typically scolopaxoid form whereas O. chalkae is comparatively shorter in lip length and far more orbicular, sometimes rectangular with protuberances that are short, stocky and densely covered in white hair. The plant is short and stout with up to nine tightly packed flowers, whereas O. cornutula is a taller, more slender orchid with a loose inflorescence.
O. chalkae is an uncommon Ophrys that may be found sparingly throughout the Aegean islands, though its full range is not fully understood due to its recent discovery and confusion with other O. oestrifera group members, It flowers from early April on calcareous soils in phrygana and abandoned agriculture, particularly where there has been some cover formed by bushes and scrub.
The photographs are from Rhodes, dating from the beginning of April.
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