Calliscirpus brachythrix C.N.Gilmour, J.R.Starr & Naczi

Gilmour, C.N., Starr, J.R. & Naczi, R.F.C. 2013. Calliscirpus, a new genus for two narrow endemics of the California Floristic Province, C. criniger and C. brachythrix sp. nov. (Cyperaceae). Kew Bulletin 68: 85. DOI https://doi.org/10.1007/s12225-012-9420

Type

Type: USA, California, Alpine County, Winnemucca Lake Trail, Starr 07-039 & Thibeault (holotype CAN!; isotypes K!, NY!).

Morphology General Habit

Herb cespitose, short-rhizomatous, perennial-Culms 19 – 85 cm × 1.1 – 1.9 mm, prominently striate, occasionally scabridulous near the apex. Leaves 3 – 6, basal and cauline, striate, 10 – 85 cm × 1 – 5 mm, distal leaf longer than sheath; leaf sheaths green or light brown at base, filamentose, dry and persistent

Morphology Leaves Ligules

Ligule fimbriate with hairs 0.05 – 0.2 mm

Morphology Reproductive morphology Inflorescences

Inflorescences capitate; bracts 2 – 5, sheathless, scale-like, 0.35 – 2 cm, rarely green and large, sometimes mucronate; spikelets 5 – 30 or more, oblong-lanceoloid, 5 – 14 mm in flower and fruit, in a dense ovoid to hemispheric head of 1 or more inconspicuous branches; floral scales brown, with pale green or brown markings, sometimes red-spotted, 1 – 3-ribbed centre, ovate-oblong, 1.2 – 5.7 × 0.6 – 1.3 mm, apex acute; perianth bristles 6 (– 12), 4 – 10 mm long, antrorsely barbed, elongate, straight; barbs thin, short, sparse; anthers 1.2 – 2 mm long; style deciduous, linear, 3-fid

Morphology Reproductive morphology Fruits

Achenes 1.3 – 3 × 0.6 – 1.1 mm, dark brown, usually dull, smooth, beak short, trigonous, oblong; embryo Carex-type (Fig. 7).

Distribution

USA: California. Alpine, El Dorado, Fresno, Inyo, Madera, Mariposa, Mono, Nevada, Placer, Plumas, Sierra, Tulare and Tuolumne counties. Sierra Nevada mountain range.

Ecology

Alpine and montane meadows and seepage slopes surrounded by conifers. Often near streams, creeks or with underground seeps; alt. 1250 to 3600 m. Common associates of Calliscirpus brachythrix include Abies magnifica A. Murray, Arnica L. spp., Carex scopulorum Holm, Carex spectabilis Dewey, Darlingtonia californica Torr., Dodecatheon L. spp., Eleocharis acicularis (L.) Roem. & Schult., Gentiana newberryi A. Gray, Juncus mertensianus Bong., Kalmia L. spp., Lilium parvum Kellogg, Parnassia palustris L., Platanthera dilatata var. leucostachys (Lindl.) Luer, Pinus contorta Douglas ex Loudon, P. monticola Douglas ex. D. Don, Rhododendron L. spp., Spiranthes Rich. spp., Sisyrinchium L. spp., Tsuga Carrière spp., Vaccinium L. spp.

Conservation

Least Concern (LC) category of IUCN (2001). The number of known populations is relatively large. Extent of Occurrence is c. 24,000 km2, above the threshold (20,000 km2) for Vulnerable. In addition, most of the known occurrences are in protected areas (several national forests). Thus, despite being endemic to the Sierra Nevada mountain range in California, the future appears secure for Calliscirpus brachythrix.

Note

Distinguished by its short ligule hairs, narrow floral scales, and less densely scabridulous bristles. Localities for this species are all found within the Sierra Nevada mountain range. Although the habitat for Eriophorum crinigerum (A. Gray) Beetle s.l. has often been cited as being commonly associated with serpentine substrates (Ball & Wujek 2002; Baldwin et al. 2012), no labels for Calliscirpus brachythrix make any mention of serpentine or related rock formations despite their presence in the Sierra Nevadas.

The specific epithet brachythrix combines the Greek prefix brachy- meaning ‘short’ with the Greek root -thrix meaning ‘hair’ to highlight the defining character of short ligule hairs that clearly separates Calliscirpus brachythrix from its sister species, C. criniger.

This species differs from Calliscirpus criniger (A. Gray) C. N. Gilmour, J. R. Starr & Naczi by its shorter ligule hairs, narrower floral scales, and less dense bristle barbs.