Rhynchospora shepherdii K. Alves, W. Thomas

Rhynchospora shepherdii K. Alves, W. Thomas & A. Gil, sp. nov. ( Figs. 1 View FIGURE 1 , 2 View FIGURE 2 , 3 View FIGURE 3 , 4 View FIGURE 4 )

Type:— BRAZIL. Minas Gerais: Frutal, 20°01’28.9”S, 48°56’26.2”W, 600 m elev., 18 April 1978, G. J. Shepherd, J.B. Andrade, J.Y. Tamashiro, P.R. Salgado 7383 (holotype MG060788, isotype UEC 043852).

Herbs, cespitose, perennial, 13–50 cm tall; base rhizomatous, not bulb-like, rigid, not fibrous, not covered by old sheaths, greenish to ochraceous; rhizomes not creeping, not squamous, inconspicuous, 1–1.4 mm wide, roots 0.3–0.8 mm wide. Leaves mostly basal, the lowest not burned off, 1–2 cauline per scape, sheaths 1.5–4 cm long, papyraceous to membranaceous, glabrous, the inner band membranous, greenish to ochraceous; blades 3.5–22 × 0.07–0.3 cm, linear, 1/2 to 2/3 the height of the stems at maturity, flattened, papyraceous, soft, greenish to ochraceous; margins antrorsely scabrous, glabrous to ciliate, the midvein unarmed, and glabrous adaxially, scabridulous to smooth, and ciliate abaxially, the surfaces glabrous, apex narrowly acute. Stems 8–46 × 0.06–0.8 cm, subtriangular in cross-section, glabrous, unarmed, greenish to ochraceous. Spikelets dimorphic. Culmless spikelets clustered at the culm tillering zone, 5.3–6.5 × 0.7–1.1 mm, narrowly lanceoloid; 2 flowers per spikelet, 1 bisexual and 1 staminate; glumes 4–5, 2–5.5 × 0.8–1 mm, yellowish brown to hyaline; lower glumes 1–2, 1.8–2.3 × 0.6–0.8 mm, sterile, apex aristate; upper glumes 2–3, 3.2–6.1 × 0.6–0.8, fertile, apex narrowly acute; spikelet bracts 1.6–4.2 × 0.8–1 mm, margins densely ciliate apically. Involucral bracts 6–9, 0.5–2 × 0.1–0.2 cm, exceeding the inflorescences, spirally imbricated, linear-lanceoloid, ochraceous, papyraceous to membranaceous, foliaceous, the midvein glabrous, unarmed, the margins densely ciliate, the marginal trichomes 0.4–1.6 mm long., the margins unarmed to scabrous, the apex narrowly acuminate to narrowly acute. Inflorescences capituliform, hemispherical, 0.6–1.4 × 1.3–1.6 cm, comprising by numerous spikelets, each spikelet subtended by a spikelet bract and a prophyll; spikelet bracts 4–4.5 × 0.6–0.9 mm, glumaceous, ochraceous, the margins ciliate medially to apically, apex narrowly acuminate; spikelet prophylls 0.9 × 0.4–0.7 mm, glumaceous, with 2-keels, ciliolate, apex short acuminate; upper spikelets (spikelets of the inflorescence) 5.4–5.8 × 0.9–1.4 mm, hermaphrodite, narrowly lanceoloid, glumes 5 per spikelet, ovoid to narrowly lanceoloid, ochraceous to vinaceous, margins hyaline, semiglossy, glabrous, apex narrowly acute, membranaceous, the inner upper one hyaline to ochraceous, basal sterile glumes 2, 1.2–2.8 × 1.2–1.6 mm, fertile glumes 3, 3.3–5.2 × 1.4–1.9 mm. Bisexual flower 1, styles undivided, stamens 3, anthers 1.3–2.2 mm long, apex narrowly acute; male flower 1. Nutlets 1.7–2 × 0.6–0.8 mm (without the style base), long-obovoid, brownish, margins yellowish, concave surface papillose distally, microreticulate and puncticulate, convex surface papillose on the central axis, microreticulate and puncticulate, hexagonal epidermal cells with central conical silica bodies, margins apterous, entire. Style base 0.7–1 × 0.3–0.6 mm, lanceoloid, yellowish, midvein inconspicuous, base 2–lobed, apex narrowly acuminate, margins antrorsely scabridulous, serrulate, apterous, with a basal constriction, not decurrent. Perianth bristles 5, 3.9–4.3 mm long, plumose up to 0.7–0.8 mm of the bristle’s length, antrorsely scabridulous medially to distally, exceeding the nutlet and the style base.

Distribution and Habitat: — Rhynchospora shepherdii occurs in the Cerrado vegetation of Central Brazil ( Eiten 1972), where according to Goodland (1971), the predominantly herbaceous vegetation is called ‘sedge meadow’, which occurs on the margins of palm marshes.

The type specimen was collected in the Frutal municipality, Minas Gerais State, Brazil ( Fig. 5 View FIGURE 5 ). Frutal is influenced by the Cerrado and Atlantic Forest phytogeographic domains and is in the “Triângulo Mineiro/Alto Paranaíba” region, west of the state of Minas Gerais, Southeast Brazil ( Goodland 1971).

Rhynchospora shepherdii was also collected by the Swedish botanist Anders Regnell in 1849 and 1857 in what is now the state of São Paulo. Regnell made many botanical collections in the region, which were deposited in his Regnellian herbarium, with duplicates sent to Stockholm, Uppsala, and other herbaria ( Santos 2016). However, there is an inconsistency regarding the location of the collection labeled A. Regnell III 1314, which is duplicated: two sheets refers to R. panicoides Schrad. ex Nees View in CoL ( US 203576, US 819616), collected in Caldas, Minas Gerais, while the other refers to R. shepherdii ( US 209546), collected in São Paulo Province. Due to the unclear location of the collections, it is not possible to be certain about where the sample was collected (São Paulo or Minas Gerais State), but it is likely that it was collected by Regnell during his travels on horseback in the vicinity of the city where he lived ( Santos 2016).

Additionally, in São Paulo, there are disjunct areas of Cerrado ( Eiten 1972), and at the beginning of the twentieth century, 14% of the current São Paulo State was covered by Cerrado vegetation ( Durigan et al. 2003). It is possible, therefore, that the species’ original distribution was between the Cerrados of São Paulo State and the “Triângulo Mineiro” region in Minas Gerais State, Southeast Brazil.

Etymology: —The specific epithet honors George John Shepherd, who collected the type specimen. George Shepherd is a Scottish botanist, now retired, who worked for many years in the Department of Plant Biology at the Campinas State University, Brazil. He made many collections in southeast Brazil, contributed to the Phanerogamic Flora of São Paulo State, Brazil (e.g. Wanderley et al. 2002, 2003, 2005), and was instrumental in training the next generation of botanists in the country, including studies involving Cyperaceae (e.g. Muniz & Shepherd, 1987, Vitta 2005).

Conservation status: —The species habitat is threatened by the increase of agriculture in the region. According to Prado-Júnior et al. (2020), who monitored the “Triângulo Mineiro” Region between 2000 and 2016, there was growth in the number of areas used for agriculture, as well as a reduction in native vegetation areas, accompanied by a higher incidence of fire outbreaks and an increase in temperature. The authors also observed severe droughts in the region between 2014 and 2015, data that corresponds to the IUCN (2022) sub-criterion B2b (iii) about inferred decline in habitat quality. Durigan et al. 2003 indicate that the advance of agriculture has reduced areas of Cerrado in São Paulo State to less than 7% of its original distribution.

Rhynchospora shepherdii might be classified as Data Deficient (DD) according to IUCN Red list ( IUCN 2022). The species is known only from the type specimen and two collections with uncertain locality data, it is not possible to estimate precisely the Extent of occurrence (EOO), the Area of occupancy (AOO), and to be more certain about how many populations of the species are known (criteria B1a, and B2a). More data about its occurrence and distribution is needed to infer the conservation status of the species according to the B2 criterion of the IUCN (2022).

Additional specimens examined (paratypes): — BRAZIL. Prov. São Paulo, 1857, A.F. Regnell III 1314 (US02253815!, P01707993 photo!) ; 1849, A.F. Regnell III 1514 ( US 02253816!) .

Notes: — Rhynchospora shepherdii can be confused with R. hirta (Nees) Boeckeler (1869: 146) due to the hemispherical inflorescences, involucral bracts with narrowly acuminate apices and densely ciliate margins, and concave-convex nutlets with entire margins. However, R. shepherdii differs by the presence of amphi-basicarpic spikelets, 5 glumes per upper spikelet, with 2 basal sterile glumes and one male flower per upper spikelet, nutlet surface trichomes with rounded apex, and style base with serrulate margins (vs. amphi-basicarpic spikelets absent, 6–7 glumes per upper spikelet, 3 basal sterile glumes, and two male flowers per upper spikelet, nutlet surface trichomes with acute apex, and style base with entire margins in R. hirta , Table 1, Fig. 4 View FIGURE 4 ).

In herbarium collections, the specimens of R. shepherdii has also been mistaken for R. armerioides J. Presl & C. Presl (1828: 197) due to the spirally imbricated involucral bracts with ciliate to ciliolate margins, hemispherical inflorescences, perianth formed by 5 bristles and exceeding the nutlet and style base, and nutlets with punctuate and papillose surfaces. However, Rhynchospora shepherdii can be distinguished by presence of amphi-basicarpic spikelets, upper spikelets shorter (5.4–5.8 mm long), 5 glumes per upper spikelet, 1 upper hyaline glume, surrounding 1 male flower, and shorter perianth bristles 3.9–4.3 mm long (vs. amphi-basicarpic spikelets absent, upper spikelets 7–11.5 long, 7 glumes per upper spikelet, 2 upper hyaline glumes, surrounding 2 male flowers, and longer perianth bristles 5–9.1 mm long in R. armerioides , Table 1, Fig. 4 View FIGURE 4 ).

Rhynchospora shepherdii is also similar to R. barbata (Vahl) Kunth (1837: 290) View in CoL due to its foliaceous, spirally imbricate involucral bracts with ciliate margins, and the hemispherical to globose inflorescences. However, R. shepherdii differs by its amphi-basicarpic spikelets and 5 glumes per upper spikelet with the lowermost 2 sterile (vs. amphi-basicarpic spikelets absent and 6–8 glumes per upper spikelet with the lowermost 3 sterile in R. barbata View in CoL , Table 1, Fig. 4 View FIGURE 4 ).