S. sennii was first described from the Greek island of Kythera by Renz in 1928 and is named in honour of the Swiss botanist G.A.Senn. It is a member of the S. orientalis group of Serapias.
It has a somewhat disjunct distribution in the Aegean region, comprising the southern Peleponnese including Kythera, the island of Kea in the Cyclades archipelago and then the Dodecanese islands of Kos and Samos, It is suspected the species has a wider range but this has yet to be confirmed. S. sennii is a rare species which grows in small numbers in only a few widely scattered locations. It is a plant of dry grassy meadows, wasteland, phrygana and abandoned terraces on predominately alkaline soils. It seems to appreciate a degree of cover and will frequently grow within the shade and partial protection of bushes and shrubs.
This is one of the easier members of the Serapias group as it exhibits two key features that help considerably with identification. The first of these is the epichile colouration which is invariably tinted dark orange rather than standard Serapias brick red. Secondly the lateral lobes of the hypochile are separated and do not form a complete arch within the hood (picture 5 illustrates this point very well). S. sennii is few flowered, the inflorescence is short and the bracts rarely exceed the length of the hood. The plant is small in stature (up to 20cms) and usually rather weedy with a small number of clasping, often broad, longish lanceolate leaves. The stem is usually tinged red, particularly at the leaf axils.
The photographs come from Kos, Samos and the Peloponnese dating from the second week of April at which time the flowers were just appearing.
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