Perrierophytum malvocoeruleum (Hochr.) M.M. Hanes & Callm.

Hanes, Margaret M., Mashburn, Brock & Callmander, Martin W., 2022, Transfer of the endemic Malagasy species of Kosteletzkya to Hibiscus and Perrierophytum (Malvaceae), Candollea 77 (2), pp. 161-171 : 166-168

Perrierophytum malvocoeruleum (Hochr.) M.M. Hanes & Callm. , comb. nov. (F ig. 4B).

Kosteletzkya malvocoerulea Hochr. in Annuaire Conserv. Jard. Bot. Genève 20: 100. 1917.

Holotypus: MADAGASCAR. Aeg. Haute Matsiatra [Prov. Fianarantsoa]: W du massif d’Andringitra , [22°13'S 46°55'E], 1000 m, IX.1911, fl., Perrier de la Bâthie 5467 [as “ 69 ” at G] ( G [ G00014375 ]!; iso-: P [ P00037094 , P00037095 ]!) .

Vernacular names. – “Tsietilahy” (Rakotovao 801); “Hafotra” (Réserves Naturelles 2266).

Distribution and ecology. – Known from rocky summits in montane ericoid thicket from 1000–2650 m; Andringitra , valleys of Riambava and Antsifotra (F ig. 3).

Conservation status. – Perrierophytum malvocoeruleum has been collected from six subpopulations in south-central Madagascar, three of which are within Andringitra National Park. No collections are known to have been made outside of the park in the past 54 years, and the most recent of these is Haine 200 from SW of Ambalavao. With all collections included, the EOO of P. malvocoeruleum is estimated to be 739 km ², and the AOO is estimated to be 32 km ². However, given recent habitat loss in this region outside of the park, and the lack of recent collections, we infer a decline in the number of subpopulations. Thus, if we do not include these subpopulations in our assessment, P. malvocoeruleum has an AOO of, at most, 8 km ². In addition, collection details for specimens thought to occur within the national park are vague, and so we infer a single location within the park. Even though this one location is within a protected area, loss due to fire or illegal incursions of forest clearing and/or grazing animals is still possible. Given these measures and the inferred recent decline in number of subpopulations from three to one, P. malvocoeruleum can be assessed as “Critically Endangered” [CR B2ab(i, ii, iii, iv, v)].

Notes – Perrierophytum malvocoeruleum has solitary, axillary flowers on long, delicate peduncles that are clustered at branch tips. F lowers of this species have a unique combination of a cupuliform calyx and filiform epicalyx with an open, flat floral architecture with gently notched petals. Perrierophytum malvocoeruleum is noted as a medicinal plant. The leaves and branches are used to treat maladies of the skin (“la gale”) (Rakotovao 801).

We consider the specimen deposited at G to be the holotype.

Additional specimens examined. – MADAGASCAR. Aeg. Haute Matsiatra [Prov. Fianarantsoa]: rocailles SO de l’Ivangomena (Pic Humbert), massif d’Andringitra , 16.X.1934, fl., Heim s.n. ( P [ P 00569770 , P 00569771 ]) ; massif d’Andringitra , vallée de la Riambava , 1924, fl., Humbert 3802 ( G, P [ P00569768 ]) ; massif d’Andringitra , IV.1911, fl., Perrier de la Bâthie 13750 ( P [ P 00569766 , P 00569767 ]) ; ibid. loco, 22°10'S 46°56'E, 1650 m, 8.IV.1997, fl., Rakotovao 801 (MO-5340237, P [ P 00569764 ]) ; ibid. loco, 22. VI.1948, fl., Réserves Naturelles 1409 ( G, P [ P 00569764 ]) ; ibid. loco, 18.VII.1952, fl., Réserves Naturelles 4781 ( P [ P 00569761 , P 00569762 ]) . Aeg. Ihorombe [Prov. Fianarantsoa]: 12 km SO Ambalavao, 67 km S of F ianarantsoa, 29.XII.1968, Haine 200 ( K) ; Distr. Ambalavao, Vohitsaoka , 23.II.1960, fl., Rabevazaha 189RN ( P) ; Antaranomby , 26.VIII.1950, fl., Réserves Naturelles 2266 ( G, P [ P 00569763 , P 00553056 ]) ; Distr. Ivohibe, Antambohobe , 22.X.1953, fl., Réserves Naturelles 5865 ( P [ P00569760 ]) ; Distr. Ambalavao, Vohitsaoka , 8.II.1961, fl., Réserves Naturelles 11673 ( P [ P00574879 ]) .