Scleria didina W. Bonet Mayedo & W. W. Thomas, 2016

Mayedo, Waldo Bonet & Thomas, William Wayt, 2016, Two New Species of Scleria section Hypoporum (Cyperaceae) from Espírito Santo, Brazil, Phytotaxa 268 (4), pp. 263-270 : 266-269

Scleria didina W. Bonet Mayedo & W. W. Thomas , sp. nov., Figs. 2 , 3 C–D

The broad leaves and distinctive contraligule of Scleria didina are rare in section Hypoporum , and its small achene suggests a close relationship to S. virgata and S. variegata Steud.

Type:— BRAZIL. Espirito Santo. Mun. Santa Leopoldina: Rio das Farinhas, beira da estrada próximo do mata burro, afloramento rochoso granítico, 478 m, 20º05’.214 S, 40º 36.112W [written as 20º05’214”S, 40º36’112”W], 14 April 2008, A. P. Fontana, L. Kollmann & A. Brahim 4911 (Holotype: MBML-035591 image; Isotype: NY) .

Perennial, 0.50–1 m tall. Rhizomes and roots unknown. Stems erect, 60–80 cm x 3–5 mm, trigonous, hidden by the leaf sheaths, the faces longitudinally lined, smooth, the angles smooth or distally scaberulous. Leaves cauline and probably basal; no basal leaves seen; cauline leaves 8–10, closely spaced, the basal 3–5 with only a rudimentary blade, the rest with well-developed blades; sheaths funnel-shaped, loose, 3–8 cm long, 0.7–1.7 cm wide higher on the stem, completely covering the enclosed stem, the angles scabrous, the faces glabrous, green to pale castaneous; ligule absent; contraligule prominent, rounded, 5–10 x 10–15 mm, glabrous, auriculate with whorled venation, pale castaneous or reddish, the margin irregular; blades linear-lanceolate, 10–25 x 0.7–2 cm, glabrous to pubescent on both sides, the adaxial face with median nerve and secondary nerves scaberulous, the abaxial face with a prominent, scabrous median nerve, the margins scabrous, the apex acute, not pseudopremorphous (not abruptly contracted). Inflorescence a single terminal panicle, comprising only staminate spikelets or only androgynous spikelets; subtended by a single leaf-like bract and a peduncle 5–12 cm long; bract 6–13 x 1–2 cm, glabrous or glabrate on both sides, the median nerve scaberulous above and prominent and scabrous beneath, the margins scabrous, the apex acute; panicle 8–16 cm long, comprising 10–19 synflorescences spirally disposed on the central axis, the synflorescence axes reaching the third order of branching, winged, glabrous or puberulent, the angles scaberulous, the terminal synflorescences sessile or subsessile, contracted; scale-like bracts subtending fascicles of spikelets filiform, 1–1.5 cm long, reddish, the bases dilated, the median nerve and margins scabrous; prophylls tubular, pilose, reddish, 1 mm long. Staminate inflorescences compact, with more than 5 spikelets per branch, sessile or subsessile, the spikelets ovoid, dark red, 3.5–4 x 0.8–1 mm, with scales 3–3.5 x 0.7–1 mm, the two basal scales dark, long-aristate, glabrous and distichous, the remaining scales hyaline, spirally arranged, decreasing in size distally; staminate flowers 8–10 per spikelet, comprising 3 stamens; androgynous inflorescences more open, with up to 3 spikelets per branch, the spikelets ovoid, laterally compressed, 4.5–6 x 0.7–1 mm, sessile, pale castaneous or reddish, the spikelet scales 4.5–5 x 0.6–1 mm, lanceolate, the three basal scales sterile, distichous, glabrous, chartaceous, the median nerve prominent, terminating in a long arista scabrous along its margins, the remaining scales spirally arranged, becoming smaller distally, hyaline, glabrous, apiculate; pistillate flower usually subtended by the fifth spikelet scale, the single style divided halfway into three stigma branches, each of these filiform and flexuous; staminate flowers several, subtended by the sixth and higher scales, with three stamens. Fruit comprising a cupule subtending the achene; cupule flat, trigonous, white, remaining when the achene falls; hypogynium absent; achene subglobose, trigonous, 1.7–2 x 0.8–1 mm, exceeding the scales, glabrous, white, apiculate, the base trigonous, the surface rugose with transversely elongated warts, the base of the style normally not persistent.

Distribution and Ecology:—Known only from the region of Santa Teresa in the state of Espírito Santo, Brazil ( Fig. 4 ). Found in moist areas on rock outcrops usually at elevations of 200– 500 m.

Preliminary Conservation Status:—The habitat of this species is very limited, found only in moist areas on rock outcrops between 200 and 500 m elevation in four municipalities in the state of Espírito Santo. In addition, relative to other Cyperaceae , these plants are conspicuous and less likely to go unnoticed and uncollected. The lack of collections in similar habitats to the north or south suggests that it may really be limited to the area around Santa Teresa. We suggest, therefore, that Scleria didina deserves the status of Vulnerable due to its very limited distribution.

Etymology:—The epithet refers to the two distinctive whorls found on the large contraligule.

Notes:—Although the broad leaves and distinctive contraligule of Scleria didina are rare in section Hypoporum , its small achene with no hypogynium leaves little doubt as to its close relationship with S. virgata ( Table 1).

Additional Specimens Examined (Paratypes):— BRAZIL. Espírito Santo: Mun. Colatina, Alto de Moacir, Pedra de Cruzeiro , propr. Landislau , 150–850 m, 19°18’39”S, 40°31’45”W, 22 Feb 2006, L. F. S. Magnago, V. Demuner, M. Belizário, E. Bausen 718 (MBML-028425 image, NY) ; androgynous specimen. Mun. Marilândia, Pedra de Cruzeiro. Aguilar , 200–830 m, 19°20’54”S, 40°33’04”W, 12 Sep 2007, R. R. Vervloet, V. Demuner, E. Bausen, T. A. Cruz 3460 (MBML-031641 image, NY) ; staminate specimen; Mun. Santa Teresa, Vale do Canãa , 15 Aug 1985, H. Q. Boudet Fernandes 1409 (MBML-001480 image, NY) ; androgynous specimen; Mun. Viana, Pedra na estrada do sítio Cantinho do Cée , próximo à Igreja de São Paulo de Biriricas, 18 Jun 1995, C. N. Fraga 215 (MBML-012805 n.v., NY), Androgynous specimen .

Figures

FIGURE 2. Illustration of Scleria didina.A. Upper portion of plant showing leaves and inflorescence, with detail of summit of leaf sheath. B. Detail of inflorescence. C. Spikelets with exserted styles.D. Spikelet with fruit.. E. Opened spikelet showing scales and pistillate flower. F. Staminate flower and subtending scale. G. Achene. A–G from Fontana et al. 4911 (NY). Illustration by Bobbi Angell.

FIGURE 3. A–B. SEM photos of Scleria chasmema achene. A Whole achene. B Achene surface. (A–B, A.P. Fontana et al. 4911). C–D. SEM photos of Scleria didina achene. C Whole achene. D Achene surface. (C–D, W. Boon [Boone] 237).

FIGURE 4. Distribution of Scleria chasmema (blue dot) and S. didina (red dots) in the state of Espírito Santo, Brazil.