Schoenoplectiella patentiglumis (Hayasaka) Hayasaka, J. Jap. Bot.

Verloove, Filip, Mesterházy, Attila & Browning, Jane, 2016, Studies in Schoenoplectiella (Cyperaceae) in tropical West Africa, Phytotaxa 283 (1), pp. 96-100 : 97-98

Schoenoplectiella patentiglumis (Hayasaka) Hayasaka, J. Jap. Bot. 87(3): 181. 2012. ( Figure 1 )

≡ Schoenoplectus patentiglumis Hayasaka, J. Jap. Bot. 78: 65. 2003.

TYPUS: South Africa: KwaZulu-Natal: Lower Umfolozi District, Umfolozi Game Reserve, ca. 700 ft, 16 Augustus 1957, C.J. Ward 3137 (holotypus: NU).

Annual, 30–60 cm tall. Culm terete, septate, 1–4 mm wide. Involucral bract septate, 20–40 cm long. Spikelets 1–12, sessile, 7–15 × 6–8 mm, stramineous. Glumes broadly ovate, 4–5 × 2–4 mm, spreading, leaving parts of rachilla exposed. Perianth 0. Stamens 3. Styles 2-branched or 3-branched. Nutlet biconvex to plano-convex (from 2-branched styles), 2.1– 1.9 mm; and/or equilaterally trigonous (from 3-branched styles), obovoid, 1.6–1.8 × 1.3–1.5 mm; surface smooth to faintly longitudinally sinuate. Nutlet in basal florets (if present) 3–4 × 3 mm.

Habitat: at the edge of temporary pools.

Distribution: Southern Africa ( Botswana, Mozambique, Namibia, South Africa, Swaziland, Zambia and Zimbabwe), tropical West Africa ( Benin, Burkina Faso, Nigeria). Possibly overlooked elsewhere in (sub-) tropical Africa.

Examined specimens (from West Africa):

BENIN, wet mud at the edge of laterite pool near Férou, 453 m, 10°55’09’’N, 01°48’56’’W, 5 December 2009, A. Mesterházy BEN86 ( BP).

BURKINA FASO, Oudalan-Oursi , nord-ouest de la montagne de Warga, petite mare sur la piste vers « le bois aux éléphants », environ 14°33’ nord, 0°32’ ouest, 320 m, 6 October 1976, P.A. Schäfer 6299 (P 00525147; sub Schoenoplectus cf. articulatus ) .

NIGERIA, Bauchi State, Yankari Game Reserve, Sha’aman Track c. 2.5, temporary waterhole, c. 9°45’ N, 10°30’ E, in tufts, plant dark green, inflorescence green, anthers and stigmata white, 22 October 1970, C. Geerling 3014 ( BR 0000021165405 , dupl. from WAG-L; sub Schoenoplectus spec. ) .

2. Schoenoplectiella raynaliana and S. proxima are conspecific

Schoenoplectiella raynaliana (U. Scholz) Lye (syn.: Schoenoplectus raynalianus U. Scholz ) was described based on a single collection from a rice field in northern Togo ( Scholz 1981). The species was accepted by recent workers (e.g., Lye 2003, Hayasaka 2002, Govaerts & Simpson 2007). It was said to be part of Schoenoplectus sect. Supini , its closest relatives probably being S. lateriflorus (J.F. Gmel.) Lye , S. erectus (Poir.) Palla ex J. Raynal and S. oxyjulos (S.S. Hooper) J. Raynal. However, U. Scholz may not have been aware of S. proxima (Steud.) Lye , an African species with a widespread but scattered occurrence ( Hayasaka 2002), since no mention was made of it. The latter corresponds in every detail with Scholz’ S. raynalianus , except for the number of stamens (respectively 3 vs. 2). In Schoenoplectiella stamen number may serve as additional criterion in distinguishing species although the number is sometimes difficult to assess since stamens easily fall off, especially in small annuals ( Hayasaka 2002). Moreover, the number of stamens may vary within a single species (e.g., in S. roylei (Nees) Lye ; Haines & Lye 1983, Hoenselaar et al. 2010). Thus, stamen number can be indicative but not decisive to separate closely similar species in Schoenoplectiella .

Hayasaka (2002) accepted Schoenoplectus raynalianus in his monographic study of Schoenoplectus but had not seen a voucher specimen. The holotype is stored at B and an image is available online at http://plants.jstor.org/stable/history/10.5555/ al.ap.specimen.b%2010%200166775. A photograph of a nutlet was kindly sent from the Berlin Herbarium. Our contention is that Schoenoplectiella raynaliana should not be recorded as a separate species but that it corresponds in all probability with S. proxima .

For convenience a table of comparison enumerating diagnostic features for both species is presented here under (mostly based on Scholz 1981, Haines & Lye 1983, Hoenselaar et al. 2010).

Figures

FIGURE 1. Comparison between inflorescences and nutlets (apical and adaxial views) of Schoenoplectiella patentiglumis (A) and S. articulata (B). A, A1, A2, Mesterházy BEN 86, Benin (BP); A3, A4, Robinson 2849, Zambia (K); B, Enti & Hall 1310, Ghana (K); B1, B2, Morton 6324, Ghana (K). (Photographs: J. Browning).