Disperis villosa

Kurzweil, Hubert & Manning, John C., 2005, A synopsis of the genus Disperis Sw. (Orchidaceae), Adansonia (3) 27 (2), pp. 155-207 : 197-198

64. Disperis villosa (L.f.) Sw.

Kongl. Vetensk. Acad. Nya Handl. 21: 220 (1800);

Schlechter, Bull. Herb. Boissier, ser. 1, 6: 942 (1898); Rolfe, Fl. Cap. 5, 3: 304 (1913); J . C . Manning in H . P . Linder F Kurzweil, Orch. S . Afr.: 308 (1999). — Arethusa villosa L . f., Suppl. Pl.: 405 (1781). — Dipera villosa ( L.f.) Spreng., Syst. Veg. 3: 696 (1826), nom. superfl. — Type: South Africa, Cape of Good Hope , Thunberg s.n. (holo-, S) .

Plants pubescent, to 180 mm. Leaves 2, alternate, subrotund, 6-40 × 3-23 mm. Flowers 1-4, greenish-yellow; median sepal deeply saccate, 5-7 × 3-5 mm, lateral sepals horizontally spreading, oblanceolate, 6-7 × 3-4 mm; petals falcate, clawed, basally fused with gynostemium, 3 × 1.5 mm; lip free from gynostemium, blade minute, appendage naviculate ( Figs 1E ; 12E ).

The species is known to hybridise with Disperis cucullata (see under that species).

DISTRIBUTION AND PHENOLOGY. — South Africa (Western Cape, a single record from the Eastern Cape); in sandy or clay soil in low fynbos or Restio -veld, also recorded from road verges, from near sea level to 210 m. Flowering mainly in August and September .

GROUP 10: “WEALEI GROUP” (SPECIES 65-74); FIGURE 13

Glabrous or rarely weakly hairy ( Disperis cooperi ) plants. Leaves 2-5, alternate. Median sepal mostly ovate to lanceolate and hooded, hood shallowly or deeply saccate, lateral sepals free; lip blade elongate and somewhat boatshaped, at base marginally fused to the entire lip appendage to form a concave structure, rarely ( D. oxyglossa , D. tysonii ) fusion absent or weak, blade always with verrucose elaiophores. Rostellum arms usually twisted outwards at tips.

DIAGNOSIS AND RELATIONSHIPS. — Within this group the lip shape has been used to define groups of closely related species (MANNING F LINDER 1992). Disperis circumflexa , D. concinna , D. cooperi , D. fanniniae , D. stenoplectron , D. tysonii and D. wealei all have a lip blade with an erect tip that is adherent to the petals and the median sepal. Disperis concinna , D. fanniniae and D. wealei are linked by their deflexed lip appendage, while D. cooperi and D. tysonii share a lip that is erect from the base. Preliminary molecular data are not entirely congruent with these hypotheses, and suggest that four species in this group, D. oxyglossa , D. stenoplectron , D. tysonii and D. wealei form a well supported clade that excludes D. circumflexa , D. fanniniae and D. paludosa (STEINER pers. comm.).

DISTRIBUTION. — South Africa and Zimbabwe, ranging into Madagascar.

Figures

FIG. 1. — Plants, inflorescences and flowers of Disperis species: A, D. dicerochila Summerh.; B, D. anthoceros Rchb.f.; C, D. cardiophora Harv.; D, D. capensis (L.f.) Sw.; E, D. villosa (L.f.) Sw.; F, D. circumflexa (L.) T.Durand & Schinz subsp. circumflexa; G, D. stenoplectron Rchb.f.; H, D. paludosa Harv. ex Lindl. Photos: A, C, H. Kurzweil; B, D-G, J.C. Manning; H, H. Boernitz.

FIG. 12. — Flower and floral details in the “Bolusiana group”: A, B, Disperis cucullata Sw.: A, flower; B, lip and gynostemium; C, D. bolusiana Schltr. ex Bolus, lip; D, D. macowanii Bolus, lip; E, D. villosa (L.f.) Sw., lip. Drawn from alcohol material (sources unknown).

FIG. 13. — Flowers and floral details in the “Wealei group”: A, B, Disperis paludosa Harv. ex Lindl.: A, flower; B, lip; C, D. circumflexa (L.) T.Durand & Schinz subsp. circumflexa, flower; D, D. stenoplectron Rchb.f., lip and gynostemium; E, F, D. concinna Schltr.: E, flower; F, lip; G, D. fanniniae Harv., lip; H, D. wealei Rchb.f., gynostemium. Drawn from alcohol material (sources unknown).