1/01/2000

Eriospermum armianum

77. Eriospermum armianum P.L. Perry sp. nov., E.bowieani lamina simile sed pedunculo longiore et flore majore distinguendum est. Type: South Africa, Cape Province, Springbok, Hermanusvlei, Mitchell1179 (NBG, holotypus; K, MO).

Plants with hysteranthous leaves, inflorescence up to 100 mm high.

Tuber simple or multiple, irregularly-shaped, up to 28 mm long and 22 mm wide: skin rough, greyish-brown, interior pink; growing point lateral.

Old leaf sheaths 20 mm long, 1.5 mm diameter.

Leaf solitary, erect; contemporary leaf sheath exserted up to 28 mm, 1.5-2.0 mm diameter, green; lamina ovate-cordate, up to 18 mm long and 12 mm wide; adaxial surface with enations arising in a bunch from near the sheath insertion, about 20, terete, up to 38 mm long and 1.0-1.5 mm diameter, unbranched or with one branch near the apex; lamina and enations glabrous, glaucous green.

Peduncular bract barely visible above ground.

Peduncle 75 mm long, 1 mm diameter, dark purplish-red at the base, green above.

Raceme sub-corymbose, lax, 30 mm long and up to 30 mm wide, with up to 8 flowers.

Bracts triangular, attenuate, sometimes slightly winged, 2 mm long, folded around the base of the pedicel, membranous, colourless with a pale greenish-brown midnerve.

Pedicels erecto-patent, arcuate, up to 10 mm long, greenish.

Flowers triangular, spreading, 12-13 mm diameter.

Tepals dimorphic, connate for 0.5 mm at the base, white with a green midnerve overlaid with fine red streaking; outer spreading to recurved, narrowly oblanceolate, attenuate, 7 mm long and up to 2 mm wide; inner erecto-patent to spreading, obovate, apex rounded, 5.5-6.0 mm long and 2.8-3.0 mm wide, margin irregularly denticulate along the rounded apex.

Filaments erect forming a ring round the ovary, dimorphic, white, outer adnate to the base of the tepals for 1.3 mm, lanceolate to narrowly ovate, apiculate, arched, 2.5 mm long and lmm at the widest part near the base, gradually tapering to the anther, inner adnate nearly 2 mm up the tepals, narrowly triangular, apiculate, 1.5 mm long and 1 mm wide.

Ovary ovoid, 2 mm long and 1.8 mm wide, pale green with very fine red stippling, especially forming lines at the side of the locule divisions.

Style cylindrical, 1.5 mm long, white.

Flowering time: March.

Leafing period: April to October.

Distribution and habitat: E.armianum is so far known only from one collection from the vicinity of Springbok, where an extensive population was found on talus on a cliff edge, partially shaded by shrubs (Figure 138).














Distinguishing features: In leaf this species is difficult to separate from E.bowieanum but the distributions of the two species are quite distinct. They are clearly separated in the flowering stage as E.bowieanum has a very small inflorescence with tiny almost globose flowers whereas those of E.armianum are larger (12-13 mm diameter) with spreading tepals (Figure 139).




















E.armianum is named after the collector, A.R. Mitchell, whose thorough field work in Namaqualand and Bushmanland has brought to light a number of previously unknown species.

Reference: Pauline L. Perry, A REVISION OF THE GENUS ERIOSPERMUM (Eriospermaceae)

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