Festuca exaristata E.B. Alexeev, Bot. Zhurn. (Moscow & Leningrad) 71(8): 1116. 1986.

Sylvester, Steven P., Soreng, Robert J., Sylvester, Mitsy D. P. V. & Clark, Vincent Ralph, 2020, Festuca drakensbergensis (Poaceae): A common new species in the F. caprina complex from the Drakensberg Mountain Centre of Floristic Endemism, southern Africa, with key and notes on taxa in the complex including the overlooked F. exaristata, PhytoKeys 162, pp. 45-69 : 45

Festuca exaristata E.B. Alexeev, Bot. Zhurn. (Moscow & Leningrad) 71(8): 1116. 1986. Fig. 6 , Table 1

Type.

[Lesotho] Basutoland. Above the Sani Pass, among stones, 9800 ft [2987 m alt.], 3 Feb 1959, M. McCallum Webster 483b (holotype: K (K000345250 [image!])).

Notes.

This species was not included in the treatments to southern African grasses ( Gibbs Russell et al. 1990; Fish and Moeaha 2015), nor in the checklist to Lesotho grasses ( Kobisi and Kose 2003), but is accepted in Plants of the World Online (2020), Plantlist (2020), the World Checklist of Selected Plant Families (2020), GrassBase ( Clayton et al. 2006 onwards) and Tropicos (2020). It is known from just two collections; the type from Sani Pass, bordering Lesotho and the KwaZulu-Natal Province of South Africa, and a paratype from Letsing La Letsie of the Matatiele Province of Lesotho. Exploration by the authors in the Sani Pass area failed to discover further specimens although, at the time of visiting, the authors were not searching in particular for F. exaristata and did not cover all the habitats present. The holotype label states 'Above the Sani Pass’ probably referring to the mountain slopes and ridge immediately above the Sani Pass, which were not explored by us. Our exploration largely focused on the valley bottom, which experienced very heavy grazing, with it being possible that the species may have been grazed out in these areas. As the species exhibits certain characters of both F. caprina s.l. and F. drakensbergensis , as well as other characters not found on any of these (e.g. glabrous ovaries, shorter unawned lemmas), there is also the possibility that the species is a hybrid which failed to survive into subsequent generations. However, the paratype, which was not seen by us, but was collected in 1977, 18 years after and ca. 130 km southwest of the type collection, raises doubt over this.

Alexeev (1986) distinguished this species from F. macra (= F. caprina var. macra ) and F. caprina in part by: a) leaf blade mid-vein blunt and rounded; b) panicle branches smooth; c) lemmas 4-4.2 mm long; d) lemmas unawned; e) ovary apex glabrous; f) anthers 1.5-1.8 mm long. It can be further differentiated from F. caprina var. irrasa by the basal sheaths being entire, and from F. caprina var. macra by the leaf blade abaxial surfaces being smooth. Furthermore, although not mentioned by Alexeev (1986), the type material appears to have extravaginal branching, with cataphyllous laterally-tending shoots present, differentiating this from the intravaginally branched F. caprina s.l. The species does bear some resemblance to F. drakensbergensis (see notes under F. drakensbergensis ).

Figures

Figure 6. Festuca exaristata. A Whole plant B basal part of plant showing lustrous basal sheaths and extravaginally-branched tillers with cataphylls (ca) C close-up of inflorescence. Digitised images of holotype M. McCallum Webster 483 b (K 000345250), courtesy of JSTOR Global Plants (https: // plants. jstor. org).