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| Mitrephora sirindhorniae Chalermglin, Leerat. & R.M.K.Saunders, in Leeratiwong, Chalermglin & Saunders, 2023. |
Abstract
Three new Mitrephora species (Annonaceae), M. langsuanensis sp. nov., M. sirindhorniae sp. nov. and M. sukhothaiensis sp. nov., are described from Thailand. Mitrephora langsuanensis resembles M. macclurei, but its leaves have more secondary veins, and its flowers have more carpels, with yellow-and-pink striped outer petals with a margin that becomes undulate with age. Mitrephora sirindhorniae resembles M. tomentosa, but has larger sepals and petals, longer flowering pedicels, and shorter monocarp stipes, with monocarps that have a longitudinal ridge. Mitrephora sukhothaiensis is distinct from its Thai congeners in having outer petals that reflex at maturity and inner petals with a pair of appendages on the margin adaxially. The addition of these three new taxa raises the total number of Mitrephora species in Thailand to 14. An identification key for Thai species is provided.
Keywords: Annonaceae, Mitrephora langsuanensis, Mitrephora sirindhorniae, Mitrephora sukhothaiensis, new species, Thailand
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| Mitrephora langsuanensis sp. nov. A flower buds B flower C flowering branch D, E fruits (slightly immature). Photos by P. Chalermglin. |
Mitrephora langsuanensis Leerat., Chalermglin & R.M.K.Saunders, sp. nov.
Diagnosis: Mitrephora langsuanensis is similar to M. macclurei Weerasooriya & R.M.K.Saunders, but differs in having: leaves with more secondary veins (7–14 pairs), sometimes with domatia abaxially; yellow outer petals with pink stripes, densely hairy abaxially, and with a margin that becomes undulate with age; more carpels per flower (10–12); and longer fruiting pedicels (20–25 mm).
Etymology: From the name Lang Suan district, Chumphon Province.
Local name: Phrom lang suan (พรหมหลังสวน) (Chumphon).
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| Mitrephora sirindhorniae sp. nov. A vegetative branch B, C flowers D, E sepals (ab- and adaxial) F, G outer petals (ab- and adaxial) H, I inner petals (ab- and adaxial) J, K stamens (ab- and adaxial) L carpel M fruit, composed of separate monocarp N seeds. Drawn by A. Somphrom, A–L from P. Chalermglin 640430 (PSU), M–N from P. Chalermglin 630723 (PSU). |
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| Mitrephora sirindhorniae sp. nov. A flowering branch B, C flowers D flower, showing calyx E flower, showing indument on adaxial surface of inner petals F fruit (slightly immature) G fruit (mature). Photos by P. Chalermglin. |
Mitrephora sirindhorniae Chalermglin, Leerat. & R.M.K.Saunders, sp. nov.
Diagnosis: Mitrephora sirindhorniae resembles M. tomentosa Hook.f. & Thomson, but is distinguished by its leaves that are sparsely hairy abaxially, larger sepals (8–10 by 10–12 mm), larger outer petals (40–60 by 22–35 mm), larger inner petals (14–16 by 14.5–15 mm), longer flowering pedicels (25–27 mm), shorter monocarp stipes (2.5–8 mm) and monocarps with a longitudinal ridge.
Etymology: Named after HRH Princess Maha Chakri Sirindhorn, in honour of her project on plant germplasm conservation in Thailand.
Local name: Maha phrom sirinthon (มหาพรหมสิรินธร) (general).
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| Mitrephora sukhothaiensis sp. nov. A, B leaves (ad- and abaxial) C flower buds D flower (slightly immature) E–G flowers, F, G showing the outer petals reflexed when mature, with insert in F showing adaxial surface of inner petal with inwardly folded marginal protrusions H fruit (mature). Photos by P. Chalermglin. |
Mitrephora sukhothaiensis Leerat., Chalermglin & R.M.K.Saunders, sp. nov.
Diagnosis: Mitrephora sukhothaiensis is distinct from all other species in having a combination of outer petals that reflex at maturity as well as inner petals that have inwardly folded marginal protrusions at the midpoint adaxially.
Etymology: From the name Sukhothai province.
Local name: Phrom sukho (พรหมสุโข) (general).
Charan Leeratiwong, Piya Chalermglin and Richard M. K. Saunders. 2023. Three New Species of Mitrephora (Annonaceae) from Thailand. PhytoKeys. 218: 93-107. DOI: 10.3897/phytokeys.218.91582
