Euryops subcarnosus subsp. fallax J. H. J. Vlok 2020, subsp. nov.
Creators: name: Vlok, J. H. J.
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Asterales
Asteraceae
Euryops
Euryops subcarnosus
Euryops subcarnosus dc. subsp. fallax j.h.j.vlok

description: 3.4. Euryops subcarnosus DC. subsp. fallax J.H.J.Vlok, subsp. nov.
Type: South Africa, Western Cape Province, Ladimsith (3320): about 30 km along road to Laingsburg, just west of entrance to farm Van Zylsdamme, (-BD), 430 m, 4 May 2004, J. Vlok 2839 (NBG, holo.).
Virgate, sparsely branched shrub, up to 1.2 m tall; young branches tinged reddish, leafy, older branches (>2 years old) leafless. Leaves erect with tips spreading, 3—5 x ca. 1 mm, terete, obtuse, subcarnose, glabrous, with small woolly tuft in axil, glaucus-green. Peduncles lateral in upper leaf axils, 25—40 mm long, terete, ca. 1 mm thick. Involucre widely cup-shaped, 6—8 mm diam. Involucral bracts uniseriate, 6 or 7, glabrous, connate for ca. quarter of their length, triangular, 5—6 X 3 mm, 5- to 7-veined, purplish in upper half, acute-penicillate. Ray fl orets 6 or 7; corolla yellow, tube cylindrical, 2 mm long, lamina oblong, 6 X 3 mm, 4-veined; style branches erect, spreading, ca. 1 mm long. Disc fl orets 30—35; corolla yellow, 4—5 mm long; tube cylindrical, 2 mm long; limb campanulate, 2—3 mm long, lobes triangular-acute with tip somewhat gibbous. Anthers 2 mm long with ovate appendage. Style terete, branches erect, ca. 0.5 mm long, truncate, with densely papillate tip. Pappus bristles white, numerous, 2 mm long. Cypselas 5—6 X 3—4 mm, densely lanate with white hairs that are not mucilaginous when wet. (Plate 4).
Flowering period: May to July. Populations flower prolifically, but seemingly only for a period of two weeks.
Distribution and ecology: Euryops subcarnosus subsp. fallax is known only from the Ladismith district where it occurs in Succulent Karoo vegetation, more specifically in the Western Little Karoo unit sensu Mucina and Rutherford (2006). At a finer scale Vlok and Schutte-Vlok (2015) described this vegetation as Apronveld.
Diagnosis: Euryops subcarnosus subsp. fallax differs from the current four subspecies in having a unique combination of characters. It differs from the two subspecies with entire leaves in having shorter leaves (5 mm long vs 10—50 mm long in subsp. subcarnosus and 15—40 mm long in subsp. foetidus) and in lacking an apiculus (small white apiculus in subsp. subcarnosus and pungent leaves with mucronate apiculus in subsp. foetidus). It also differs from these two subspecies in the hairs of the achenes that do not become mucilaginous when moistened (vs. mucilaginous when wet in subsp. subcarnosus and subsp. foetidus). It differs from the two other subspecies (subsp. minor and subsp. vulgaris) in having entire and not lobed leaves. It may be unique in this species complex in having functionally male disc florets, but fruiting material from more populations needs to be investigated to confirm this observation.
Euryops subcarnosus is the most widespread and variable of the South African Euryops species (Nordenstam, 1968), with E. subcarnosus subsp. subcarnosus the only subspecies previously known to occur in the Klein Karoo. No specimens intermediate between E. subcarnosus subsp. subcarnosus and E. subcarnosus subsp. fallax are known and the latter may warrant specific recognition, but with the current wide concept of the species, I regard it more prudent to treat this taxon as a subspecies.
Conservation notes: Plants are locally abundant, but currently known from only three localities (Fig. 3). At the type locality plants occur only along the fenced road reserve, with no plants within the adjacent grazed camp. From the other two localities it is also clear that the plants are highly palatable to domestic stock and game. These observations suggest that the known populations have been severely reduced due to grazing. Following Raimondo et al. (2009) I propose a conservation status of Endangered (B2 (a) & (b)) for this subspecies.
Etymology: The subspecies name (fallax) alludes to the fact that this taxon has been overlooked until now.
3.4.1. Additional material examined
South Africa. WESTERN CAPE. 3320 (Ladismith): Anysberg Nature Reserve, about 1.2 km west of Goedehoop house, (- BC), 9 July 2006, Vlok & Schutte 555 (NBG); Anysberg Nature Reserve, about 2 km west of Goedehoop house, 14 July 2007, Vlok & Schutte 606 (NBG, S).
3.4.2. Changes to species key
This subspecies can be accommodated in the existing key to the subspecies of Euryops subcarnosus (Nordenstam, 1968: 196) by changing couplet 2 to the following:
(i) Leaves 3—5 mm long, lacking an apiculus.. ... ... ... ... ... ... ... ...... subsp. fallax
(ii) Leaves> 10 mm long, with small white or pungent mucronate apiculus.. ... ... ... ..... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... continue with existing key.
description: Published as part of Vlok, J. H. J., 2020, Three new species and one new subspecies of Euryops (Asteraceae: Senecioneae) from the Klein Karoo in the Western Cape Province, South Africa., pp. 167-173 in South African Journal of Botany 133 on pages 170-172, DOI: 10.1016/j.sajb.2020.07.025, http://zenodo.org/record/10496796