Coleus caudatus (S.Moore) E.Downes & I.Darbysh., 2017

Downes, E. & Darbyshire, I., 2017, Coleus namuliensis and Coleus caudatus (Lamiaceae): a new species and a new combination in the Afromontane flora of Mozambique and Zimbabwe, Blumea 62 (3), pp. 168-173 : 172

Coleus caudatus (S.Moore) E.Downes & I.Darbysh. , comb. nov.

Plectranthus caudatus S.Moore in Rendle et al., J. Linn. Soc., Bot.40 (1911) 176; Paton et al. (2013) 284, f. 8.8.47. — Type: Swynnerton 2010 (holo BM00564028 *; iso K000432000 ), Zimbabwe, Chimanimani Mts, fl., 26 Sept. 1906.

Distribution & Ecology — Coleus caudatus is known only from the Chimanimani Mountains, which span the border between Manica Province of Mozambique and Manicaland Province of Zimbabwe. This aromatic perennial herb occurs in rocky areas in upland grassland over quartzite, most often growing on rock outcrops and faces; it occurs at 915–1680 m elevation.

Additional specimens. MOZAMBIQUE, Chimanimani Mts , on edge of Goye, fl., 2 Sept. 1944, Finlay F17 ( SRGH *) ; Chimanimani Mts , fl. fr., 1973, Dutton 83 ( LMA (not seen)); Chimanimani Mts, northern slopes below Mt Dombe, S19°44'39" E33°00'57", st., 17 Apr. 2014, Ballings & Wursten PB 2227 ( K, LMA (not seen), SRGH (not seen)) . – ZIMBABWE, Chimanimani Mts ,fl. 15 May 1947, Munch 1 ( SRGH *) ; Chimanimani Mts , fl., 4 June 1948, Munch 102 ( SRGH) ; Chimanimani Mts , fl. fr., 6 June 1949, Wild 2874 ( K, SRGH *) ; Chimanimani Mts ,fl., 8 July 1950, Thompson 20 ( SRGH *) ; Musapa Gap ,fl., 6 Oct. 1950, Munch 348 ( SRGH *) ; Chimanimani Mts , ‘ The Corner’, fl., 8 Oct.1950, Chase 2990 ( SRGH *) ; Chimanimani / Bundi, fl., 16 Mar. 1957, Phipps 690 ( SRGH *) ; Chimanimani Mts , Stonehenge,fl., 1 Feb. 1958, Hall 281 ( SRGH *) ; Chimanimani Mts , summit of pass, fl., 18 May 1958, West 3637 ( SRGH *) ; Chimanimani Plateau , fl., 26 May 1959, Leach 9040 ( SRGH *) ; Chimanimani Mts , fl., 29 Sept. 1966, Plowes 2806 ( K, SRGH *) ; Chimanimani Mts , Higher Valley, fl. fr., 8 Apr. 1967, Grosvenor 364 ( K, SRGH *) ; Chimanimani Mts , fl., July 1972, Goldsmith 27/ 72 ( K, SRGH *) ; Chimanimani Mts , Bailey’s Folly, fl., 11 Sept. 1981, Burrows 2391 ( SRGH *) .

Conservation — Coleus caudatus is known only from a very small range, with an Extent of Occurrence of 39.5 km 2 based on occurrence data and with the maximum range not exceeding 270 km 2 which is the maximum extent of craggy quartzite and associated grassland on Chimanimani. However, it is considered to be secure there as there are no known threats to its favoured rocky habitats and the entirety of this population falls within protected areas. Whilst the protection is less effective on the Mozambique side of the border than in Zimbabwe, the human impacts within the Chimanimani National Reserve are diminishing and do not impact upon the favoured habitats of this species ( Timberlake et al. 2016). It is therefore assessed as of Least Concern (LC) at present, but any increased pres- sure on the montane habitats of the Chimanimani massif may quickly result in this species becoming globally threatened. In the longer term, climate change may pose a threat to this species, hence regular surveys are desirable to monitor any indications of population decline or range shift. In the National Plant Red List of Zimbabwe, Mapaura & Timberlake (2002) recorded this species as Near Threatened, but in the absence of any threats the assessment is downgraded to LC here.