Pauridia minuta (L.f.) Durand & Schinz (1895: 142)

Snijman, Deirdre A., 2014, A taxonomic revision of the genus Pauridia (Hypoxidaceae) in southern Africa, Phytotaxa 182 (1), pp. 1-114 : 40-42

8. Pauridia minuta (L.f.) Durand & Schinz (1895: 142) . Fig. 16

Bas.:— Ixia minuta Linnaeus (1782: 92) ≡ Pauridia hypoxidioides Harvey (1838: 342) , nom. illeg., superfl. Type (lectotype designated by Thompson 1979: 621):— SOUTH AFRICA. [Cape] Cap. b. Spei, Thunberg s.n. (UPS-THUNB! No. 974 [microfiche])

= Pauridia minuta var. muirii Brown (1933: 24) . Type (lectotype designated by Thompson 1979: 621):— SOUTH AFRICA. Riversdale Division, J. Muir (K, isolectotype BOL!)

Plants 1.5–8 cm tall. Corm more or less globose, 5–8 mm diam., covered with reticulate, brown fibrous tunics, sometimes producing runners terminating in cormlets; fibres attached to basal disc, ending in a sharp point distally; roots slender, arising close to corm base. Cataphylls membranous, up to ca. 7 mm long. Leaves 3–7, sheathing at base up to 3.5 cm, somewhat erect to spreading, narrowly to broadly linear, 10–100 × 0.5–5.0 mm, attenuate proximally, terete to canaliculate, margin entire or rarely minutely papillate. Inflorescences 1–3(–5) in flower at a time, 1(2)-flowered, shorter or longer than leaves; scape up to 50 × 0.5 mm, often hidden amongst leaves, greenish white; bracts 2, clasping pedicel at base, filamentous, 1–10 × 0.5 mm, membranous. Flowers pedicellate, campanulate to shortly funnelform, white, usually greyish in throat, backed with pale pink in both whorls, sometimes striped or tipped with green or reddish green in outer whorl, sometimes faintly sweet-scented; pedicels spreading, recurved during fruit development, becoming horizontal when ripe, 2–33 × 0.5 mm, pale green to pale pink; perigone tube 1–4 × 2 mm, tepals 6, outspread, oblong-elliptic, as long as to slightly more than twice as long as tube, 3–5 mm long, outer 1.5–2.5 mm wide, minutely mucronate, inner 1.2–2.0 mm wide. Stamens 3, more or less erect; filaments inserted on tube below inner tepals, 0.4–1.0 mm long, shorter than anthers; anthers oblong, latrorse, 1.0– 3.5 mm long, basal lobes up to 0.5 mm long, apex sometimes deeply notched, pale yellow or white. Ovary obconical, ca. 2.0 × 1.5 mm, 3-locular, rarely 2- or 1-locular; style 0.2–1.5 mm long; stigma branches 3, erect, linear, up to 4 mm long, shorter than or exceeding stamens, white, margin minutely papillose in distal ⅔ or rarely throughout, occasionally some lobes absent, with a short downturned hook developed at or shortly below each branch cleft. Capsules ovoid-obconic, ca. 2.0 × 1.5 mm, walls moulded over seeds, disintegrating irregularly. Seeds globose, ca. 0.44 × 0.40 mm; testa shiny black, covered with rounded elevations in close-set, longitudinal rows, outer periclinal cell walls somewhat hemispherical, with a flat rim. Flowering period: April–mid-June.

Distribution and habitat:— Pauridia minuta is found predominantly on the coastal forelands extending from near Vredenburg in the northwest, southwards to the Cape Peninsula, Western Cape and eastwards to near Humansdorp and Port Elizabeth, Eastern Cape ( Fig. 17A ). The species also extends inland, reaching the mountains of the Ceres District and a number of major gorges through the Cape Fold Mountains of the Little Karoo. Isolated populations of scattered or densely aggregated plants occupy shallow pockets of soil on sandstone, limestone and granite outcrops, as well as gravelly clay and loamy flats. Flowering usually starts in April, approximately two days after the first autumn showers, and lasts for brief intervals of five or six days until rain falls again. Flowering finally ends when regular winter rains set in, usually in June ( Markötter 1936). Individual flowers are open from morning until shortly after sunset, several hours longer than most other species in the genus.

In the recent Red List of South African plants ( Raimondo et al. 2009), based on IUCN Categories and Criteria, P. minuta is regarded as Near Threatened due to urban development and the invasion by alien plants on the coastal forelands in Western Cape.

Diagnostic features:—Despite the considerable variation in leaf width and flower size within the species, Pauridia minuta is easily recognized by the presence of only three stamens, an attribute shared with its sister species P. longituba . P. minuta is separated from P. longituba primarily by its smaller, pedicellate flower in which the perigone tube is shorter than or at most equal to the tepals. In contrast, the flower of P. longituba has an elongated perigone tube, ranging from two to three times longer than the tepals, it lacks a distinct pedicel and the ovary is usually subterranean.

Variation:—Plant habit varies from extreme dwarfism, often in populations occupying hard clays or shallow loams on stone pavement, to small sized individuals of about 8 cm tall. Throughout most of its range, plants remain narrow-leaved (less than 1 mm wide) except around Stellenbosch and in the Overberg where some populations have broad, carinate leaves up to 5 mm wide.

Although the flowers remain constant in form, they differ in size and rarely lack a stigma, thus are functionally male. The short stigma lobes, which develop from the clefts between the three long stigma branches, have a vascular supply similar to that of the outer filament whorl in species with six stamens and infrequently these give rise to an anther ( Thompson 1978). Whereas Rudall et al. (1998) interpreted these lobes as staminodes that are fused to the style, Burtt (2000) suggested that their development as stamens has been ontogenetically delayed, resulting in their formation as pseudostigmatic hooks. The presence at anthesis of minute amounts of exudate on these hooked lobes (Snijman pers. obs.) and a report that pollen deposited in the small adaxial groove on each lobe germinates there ( Thompson 1972b) suggests that the tissue is fully stigmatic. The anthers of P. minuta also vary in colour, despite being constant in all other taxa of the genus. On the Altantic Coast forelands plants often have yellow anthers, whereas they have white anthers elsewhere.

Additional variation is expressed in the mode of seed dispersal which is still insufficiently known for P. minuta . In open ground on the Stellenbosch Flats, the fruiting pedicels of plants bend down vertically towards the ground from an almost erect scape and later assume a horizontal position once the fruits begin to disintegrate ( Markötter 1936). In contrast, some plants growing in the crevices of granite outcrops on the Atlantic Coast, near Vredenburg, are almost geocarpous. After flowering, the pedicels abruptly bend downwards from the articulation with the scape until almost level with the soil and then they curve upwards just below the fruiting head, thus becoming sigmoid. During this period the scape also curves downwards and in doing so helps to deposit the fruit on or slightly below the ground.

Brown (1933), who described P. minuta var. muirii from the Riversdale District, stated that it “seems to differ from the type only in its smaller size and more eastern locality”. Thompson (1979), however, clearly understood the variable nature of the species and chose not to uphold this variety.

History:—Plants in undisturbed situations often form dense carpets, providing massed displays which were considered remarkable enough to evoke comment by early botanists. Markötter (1936), for example, counted 450 open flowers within an area of only 643 square cm on the flats near Stellenbosch between 1928 and 1930. A century earlier, when describing Pauridia for the first time, Harvey (1838), the Colonial Treasurer at the Cape between 1936 and 1938, wrote: “the flowers snow-white and covering the ground like a shower of brilliant little stars”—an apt description which reveals his obvious delight in possibly the tiniest geophyte in South Africa’s flora.

Additional specimens examined:— SOUTH AFRICA. Western Cape: Jacobsbaai (QDS: 3217 DD), May 2008, Koopman s.n. ( NBG 212044 !) ; top of granite dome at Witteklip (QDS: 3217 DD), 26 June 2002, Manning s.n. ( NBG!) ; Vredenburg, Witteklip (QDS: 3217 DD), 5 June 2004, Rowe & Manning 4 ( NBG!) ; Witklip Farm , 5 km Sof Vredenburg (QDS: 3217 DD), 16 June 1964, Thompson 21B ( NBG!) ; Witklip , 3 km Sof Vredenburg (QDS: 3217 DD), 7 June 1965, Thompson 93 ( NBG!) ; 5.8 km from Vredenburg on road to Saldanha on Farm Witklip (QDS: 3217 DD), 13 June 1967, Thompson 278 ( NBG!) ; Langebaan, Basson’s Farm (QDS: 3318 AA) , Axelson 413 ( NBG!) ; Langebaan (QDS: 3318 AA), 5 June 2004, Rowe & Manning 2 ( NBG!) ; Muishondklip (QDS: 3318 AA), 31 May 1978 , Thompson 3816 ( NBG!); Langebaan , Meeuklip (QDS: 3318 AA), 31 May 1978 , Thompson 3818 ( NBG!); Septembersklip , NE of Langebaan (QDS: 3318 AA), 31 May 1978 , Thompson 3819 ( NBG!); between Mamre and Darling (QDS: 3318 AD), Salter 2404 ( BOL!); Farm Rondeberg , SW of Darling (QDS: 3318 AD), 23 May 2001 , Snijman 1812 ( NBG!, PRE!); 1.6 km from Malmesbury on road to Klipheuwel (QDS: 3318 BC), L. Bolus s.n. ( BOL!); Klipberg, Darling (QDS: 3318 BC), 22 June 2002 , Bruyns 9068 ( NBG!); Malmesbury, Constable Hill (QDS: 3318 BC), Macnae s.n. ( BOL!); Kenilworth , near Cape Town (QDS: 3318 CD), April 1894 , H. Bolus 2815 ( BOL!, PRE!); Green Point (QDS: 3318 CD), Ecklon 4130 ( BOL!); Kenilworth Race Course (QDS: 3318 CD), Esterhuysen 31957 ( BOL!); Rondebosch Common (QDS: 3318 CD), 18 June 1949 , Heginbotham 5 ( NBG!); Cape Observatory near Rondebosch (QDS: 3318 CD), June 1883 , MacOwan 2615, Herb. Norm. 291 ( SAM!); Rondebosch Common (QDS: 3318 CD), 5 June 2004 , Rowe & Manning 3 ( NBG!); Green Point (QDS: 3318 CD), May 1887 , Thode s.n. Herb. University Stellenbosch 8376 ( NBG!); Camp Ground (QDS: 3318 CD), Wolley-Dod 2558 ( BOL!); Kalabaskraal (QDS: 3318 DA), 4 June 1971 , Strauss 102 ( NBG!); Kalabaskraal (QDS: 3318 DA), 8 June 1965 , Thompson 103 ( NBG!); between Malmesbury and Kalabaskraal (QDS: 3318 DA), 24 May 1970 , Thompson 999 ( NBG!); Cape Town / Malmesbury divisional boundary on main road Eof Kalabaskraal (QDS: 3318 DA), 31 May 1978 , Thompson 3814 ( NBG!); Paarl Mountain (QDS: 3318 DB), 3 May 1962 , Jordaan 1261 ( NBG!); Malmesbury, Paardekop (QDS: 3318 DB), Pillans s.n. ( BOL!); ibidem, 6 May 1955 , Van Niekerk 370 ( PRE!); Langverwacht, Kuils River (QDS: 3318 DC), 23 May 1974 , Oliver 4846 ( NBG!, PRE!); Bellville, Brackenfell, Bracken Koppie , Protea Heights (QDS: 3318 DC), 16 June 2005 , Von Witt CR667 ( NBG!); Stellenbosch Flats (QDS: 3318 DD), 14 June 1963 , Bos 50 ( NBG!); Blouklippen River Bank (QDS: 3318 DD), 17 May 1997 , Boucher 6132 ( NBG!); Stellenbosch (QDS: 3318 DD), Duthie 464 ( BOL!); Stellenbosch Flats (QDS: 3318 DD), Garside 4937 ( BOL!); Jan Marais Park , Stellenbosch (QDS: 3318 DD), 11 June 1981 , Hugo 2606 ( NBG!); Elsenberg (QDS: 3318 DD), 1902, Marloth 2639 ( PRE!); Paarl Mountain Nature Reserve (QDS: 3318 DD), 13 May 2002 , Milton 1176 ( NBG!); Stellenbosch Flats (QDS: 3318 DD), 24 April 1969 , Thompson 726 ( NBG!); Jan Marais Park , Stellenbosch (QDS: 3318 DD), 12 April 1978 , Thompson 3810 ( NBG!); Gydow Pass, Ceres (QDS: 3319 AB), May-June 1931, Leipoldt s.n. ( BOL!); Eof Tulbagh, along road to Wolseley (QDS: 3319 AC), 27 May 2011 , Snijman 2365 ( NBG!); near Chavonnes Station (QDS: 3319 CB), 2 June 1977 , Perry 209 ( NBG!), 28 May 1977 , Walters 1683 ( NBG!); Villiersdorp (QDS: 3319 CD), Salter 610 ( BOL!); Gamka Reserve , Tierkloof, (QDS: 3321 DB), 24 May 1975 , Esterhuysen 33856 ( BOL!, NBG!); Grootkop, Simonstown (QDS: 3418 AB), 26 May 1946 , Compton 18000 ( NBG!); Diep River (QDS: 3418 AB), May 1916 , Marloth 7442 ( PRE!); Farm Bergvliet, Constantia (QDS: 3418 AB), Purcell s.n. ( SAM 90862!); Purcell s.n. ( SAM 90863!); Red Hill (QDS: 3418 AB), 25 May 2006 , Snijman 2040 ( NBG!); Faure , Farm Vergenoegd (QDS: 3418 BA), 2 June 2008 , Boucher 7532 ( NBG!); ibidem, 4 May 2006 , Helme 3882 ( NBG!); Strand (QDS: 3418 BB), 27 April 1946 , Gerstner 6160 ( PRE!); Somerset West (QDS: 3418 BB), 25 May 1940 , Parker 3505 ( BOL!, NBG!); Somerset West (QDS: 3418 BB), 20 April 2000 , Runnalls 483 ( NBG!); Harmony Flats , Strand (QDS: 3418 BB), 19 June 2000 , Runnalls 1001 ( NBG!), 31 April 1965 , Thompson 86 ( NBG!); Kogelberg State Forest (QDS: 3418 BD), 6 May 1992 , Kruger 549 ( NBG!); Middle Plateau overlooking Fairy Glen on Eside of Palmiet River (QDS: 3418 BD), 16 May 2004 , Snijman 1916 ( NBG!); Houw Hoek (QDS: 3419 AA), L. Bolus s.n. ( BOL!), 14 April 1896 , Schlechter 7587 ( PRE!); Farm Twaalfontein , near Vyeboom, SE of Theewaterskloof Dam (QDS: 3419 AA), 21 May 1999 , Snijman 1693 ( NBG!); Caledon Baths (QDS: 3419 AB), H. Bolus s.n. ( BOL!), 4 May 1931 , Marloth 14189 ( PRE!), 4 July 1918 , Purcell s.n. ( SAM 46271!); Caledon, hill between village and baths (QDS: 3419 AB), Guthrie s.n. ( BOL!); near Caledon (QDS: 3419 AB), 30 April 1938 , Compton 7207 ( NBG!); Caledon, Happy Valley near Greyton (QDS: 3419 AB), 12 April 1941 , Compton 10677 ( NBG!), Esterhuysen 5077 ( BOL!); NE shores of Botrivier Vlei , 1.5 km Nof Fisherhaven (QDS: 3419 AC), 28 May 1997 , Helme 1267 ( NBG!); Paardeberg Mtns , Kleinmond (QDS: 3419 AC), June 1950 , Stokoe s.n. ( SAM 63797!); Papiesvlei (QDS: 3419 AD), 14 April 1897 , Schlechter 2281 ( PRE!); ibidem, Schlechter 10444 ( PRE!); Greyton Nature Reserve , Platkloof (QDS: 3419 BA), 26 May 1979 , Rycroft 3342 ( NBG!); 5 miles [8 km] NW of Riviersonderend (QDS: 3419 BB), 25 May 1949 , Heginbotham s.n. ( NBG 64954!); foothills of the Riviersonderend Mtns (QDS: 3419 BB), May 1950 , Lewis 3022 ( SAM!); ibidem, Wilman 546 ( BOL!); Gansbaai (QDS: 3419 CB), 5 June 2004 , Rowe & Manning 1 ( NBG!); Baardskeerdersbos , Uilenkraal road at turn-off to Awila (QDS: 3419 CB), 21 May 1971 , Thompson 1194 ( NBG!, PRE!); Soutpan, opposite Springfield , SE of Elim (QDS: 3419 DB), 22 June 1997 , Helme 1282 ( NBG!); Agulhas Plain , 2 km Wof Soetendalsvlei (QDS: 3419 DB), 18 June 2008 , Helme 5511 ( NBG!); Elim , hills NW of Village (QDS: 3419 DB), 24 May 1990 , Oliver 9427 ( NBG!); Bontebok Park , Swellendam (QDS: 3420 AB), 17 May 2000 , Botha s.n. (NBG 194596!); Wydgelee (QDS: 3420 AD) , 30 May 1947, Barker 7953 ( NBG!) ; De Hoop Nature Reserve (QDS: 3420 AD) , 15 June 1979, Burgers 1883 ( NBG!) ; ibidem, 9 April 1957, Lewis 5127 ( NBG!) ; ibidem, 14 May 1998, Snijman 1656 ( NBG!) ; ibidem, s.d., van der Merwe 2066 ( NBG!) ; Suurbraak, Midddelplaas [Middelplaats] (QDS: 3420 BA) , 12 May 1982, Viviers 273 ( NBG!) ; Heidelberg (QDS: 3420 BB) , Esterhuysen 17281 ( BOL!) ; De Hoop-Potberg Nature Reserve , 1 km Wof Potberg Centre (QDS: 3420 BC) , 6 May 1982, Burgers 2880 ( NBG!) ; near Bredasdorp (QDS: 3420 CA) , Taylor 118 ( BOL!) ; Oakdale near Riversdale (QDS: 3421 AA) , April 1909, Muir 187 ( PRE!) ; Riversdale (QDS: 3421 AB) , Muir s.n. ( BOL 18402!) . Eastern Cape: Port Elizabeth , Farm Little Chelsea No. 10 (QDS: 3325 CD) , 26 May 2009, Ebrahim CR3826 ( NBG!) ; ca. 11 miles [17.7 km] Wof Humansdorp (QDS: 3424 BA) , 30 April 1947, Acocks 13731 ( PRE!) ; Nof Mpofu Dam and Wof road from Humansdorp to dam wall (QDS: 3424 BA) , 9 May 2010, Logie FBG526 ( NBG!) ; Osbosch Farm, near Humansdorp, on N side of Kromme River (QDS: 3424 BB) , 6 June 2010, Logie FBG553 ( NBG!) .

Figures

FIGURE 16. Pauridia minuta. A, whole plant; B, stamen in dorsal view; C, style and stigma branches; D, grooved style column in transverse section; E, seed. Scale bar A = 10 mm; B = 4.5 mm; C, D = 3.5 mm. Scale bar E = 0.5 mm. Drawn by Tracey Nowell from Snijman 2365 (NBG!).

FIGURE 17. Distribution maps for A, Pauridia minuta from Western and Eastern Cape; B, P. longituba from Western Cape, South Africa.