Synsepal

{{Short description|Floral structure formed by the partial or complete fusion of two or more sepals}}

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{{Wiktionary|synsepalous|gamosepalous}}

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A synsepal is a floral structure formed by the partial or complete fusion of two or more sepals.{{cite book |editor-last1=Wu |editor-first1=Zheng-yi |editor-last2=Raven |editor-first2=Peter H. |year=2009 |title=Flora of China: Orchidaceae |series=Flora of China |publisher=Science Press and Missouri Botanical Garden Press |volume=25 |page=3 |isbn=978-1-930723-90-0 |oclc=223628675}} Such sepals are said to be synsepalous or gamosepalous.{{cite web |last1=Eckel |first1=P. M. |title=A Grammatical Dictionary of Botanical Latin |url=https://www.mobot.org/mobot/latindict/keyDetail.aspx?keyWord=gamosepalus |publisher=Missouri Botanical Garden |access-date=9 October 2024 |archive-date=1 May 2021 |archive-url=https://web.archive.org/web/20210501164250/http://www.mobot.org/mobot/latindict/keyDetail.aspx?keyWord=gamosepalus |url-status=live }}

It is common among lady's slipper orchids (Cypripedioideae) that the two lateral sepals are connate to form a synsepal in the outer whorl. This is located directly behind the pouch, opposite the upward-pointing dorsal sepal.

Synsepals may be bifid, i.e. divided into two equal lobes, or forked and divided in two by a deep cleft.