O. cornutula was first described by Paulus from Rhodes in 2001 and its name refers to its diminutive size and this is indeed a very small flower. It's a member of the large O. oestrifera group and is synonymous with O. crassicornis and also O. cornuta which now refers only to a species endemic to the Caucasus.
Its tiny stature is a significant identification feature but by no means diagnostic as it's a characteristic shared with O. nestoris, O. stavri and O. miniscula amongst others. O. cornutula is a relatively spindly, lax-flowered plant but may nonetheless carry an inflorescence of up to 15 flowers and this can be regarded as a further key distinguishing feature. O. cerastes is much fewer flowered and a decidedly more robust looking plant with marginally larger flowers. One of this species more consistent features is the speculum which is complex, gaudy and can often cover a large area of the median lobe. It is also quite commonly marbled with candicoid lining and this somewhat unhelpfully gives it a close resemblance to O. stavri, a species with which it shares a range overlap on mainland Greece and Cephalonia. O. stavri is however a much more pot bellied, amphoroid flower with a smaller basal field. Nevertheless it has to be conceded that natural variation and hybridization can sometimes make differentiating the two species very difficult.
O. cornutula is a localized species but with a practically pan-Hellenic range and can often occur in huge numbers, particularly in the Aegean. The photographs are from Rhodes, Attica, the Peloponnese and Cephalonia.
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