Wrong flowers? The evolutionary puzzle of Jongkindia (Passifloraceae s.l.), a new monotypic genus and tribe from Liberia, West Africa

Abstract

Jongkindia, a small tree species endemic to a local area in southeast Liberia, is described as a new monotypic genus of Passifloraceae sens. lat. Its only species Jongkindia mulbahii combines floral characteristics of the Turneraceae and fruit characteristics of the Passifloraceae s.s. (or subfamily Passifloroideae in APG) and can therefore be regarded to occupy an isolated morphological position. This is confirmed here by DNA sequence-based phylogenetic analyses including most Passifloracean genera, which places it as sister to Passifloroideae. We delineate 16 morphological characters and their states and optimise them on our reconstructed phylogenetic tree. Based on these results we consider the Passifloraceae fruit characteristics (berries with arilled seeds) as synapomorphic for Passifloroideae. The monotypic Pibiria and Jongkindia are predominantly characterised by autapomorphies. On the other hand, the Adenia/Passiflora clade is characterised by polymorphisms. We place Jongkindia in a new tribe Jongkindieae Breteler & F.T.Bakker. A draft plastome sequence for Jongkindia mulbahii is presented and evidence for two mitome to plastome (mtpt) fragment transfers is discussed. Structurally the Jongkindia plastome appears similar to that of Populus, Adenia, Mitostemma, Dilkea, and Passiflora pittieri, but not to contain the previously-described major inversions within other, more derived, Passiflora plastomes.

Seed morphology of the paleotropical tribe Paropsieae (Passifloraceae, Malpighiales), and paleobotanical implications

“…The genus Passifloroidesperma contains fossil seeds that can only be confidently identified at the subfamily level (Martínez 2017). There are three extant tribes: Jongkindieae is at the base of the sub-family and is a sister group of both Passifloreae + Paropsieae (Breteler et al 2022). The tribe Jongkindieae has seeds very distinct from those of Passifloroidesperma.…”

“…The tribe Jongkindieae has seeds very distinct from those of Passifloroidesperma. The seed surface of Jongkindieae is tuberculate and the seed wall has a corrugated testa (Breteler et al 2022). Passifloroidesperma is characterized by a seed surface foveolate, coarsely foveolate, reticulate-foveolate or transversally grooved, and the seed coat made of prismatic palisade cells (Martínez 2017;Hermsen 2021).…”