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Viola calcicola
(Limestone violet)

[taxon report][distribution map][all photos][line drawing]

Family: Violaceae

Scientific Name: Viola calcicola R.A. McCauley & H.E. Ballard

Synonyms: None

Vernacular Name: Limestone violet

R-E-D Code: 2-1-2

Description: Acaulescent perennial herb from a short (ca 2.5 cm) vertical rhizome bearing stout fibrous roots; leaves all unlobed or rarely shallowly trilobate; petioles of longest leaves 3-7 cm; leaf blades cordate, triangular-cordate to deltoid with rounded-serrate margins, glabrous; chasmogamous flowers solitary on peduncles generally borne at or slightly above the leaf blades; sepals variable, ovate to lanceolate, the lowest 3-5 mm long and 1-2 mm wide; corolla 0.8-1.5 cm long; petals on different plants varying from nearly white (faintly flushed with violet) to medium purple, lateral petals having few inconspicuous purple veins, spurred petal with prominent and extensive nectar guides, lateral and upper petals narrowly obovate, spurred petal obovate with long-tapering base, 10-13(-15) mm long including spur, 3-5 mm wide, broadly obtuse to rounded at apex; spurred and upper petals glabrous within, lower lateral petal sparsely bearded with few to several clavate or knob-shaped hairs; cleistogamous flower buds to 3 mm long on peduncles shorter than the leaves; fruit a glabrous capsule. Flowering April to May.

Similar Species: Viola guadalupensis has flowers with yellow petals and there are no other Viola species with purple flowers in the Guadalupe Mountains. The adjacent Sacramento Mountains have Viola nephrophylla, which has purple petals, but is quickly distinguished by some pubescence on its petal spur.

Distribution: New Mexico: Eddy and Otero counties. Texas, Culberson County; escarpment and deep canyons on the eastern slope of the Guadalupe Mountains.

Habitat: Cracks in Permian age limestone in riparian woodland and montane scrub up to pinyon-juniper woodland, usually on north-facing cliff faces or near spring seeps. 1,525 m (5,000 ft) to 2,135 m (7,000 ft).

Remarks: Viola calcicola is one of a suite of chasmophilous plants endemic to the limestone cliffs of the Guadalupe Mountains and adjacent sky-island ranges. In New Mexico it is sympatric with the rare Aquilegia chaplinei, Hedeoma apiculata, Perityle quinqueflora, Polyglala rimulicola, Salvia summa, Nama xylopodum, Chaetopappa hersheyi and Valeriana texana.

Conservation Considerations: The rugged, inaccessible nature of this plant's habitat protects it from any impacts of land use.

Important Literature (*Illustration):

*McCauley, R.A. and H.E. Ballard, Jr. 2013. Viola calcicola (Violaceae), a new endemic violet from the Guadalupe Mountains of New Mexico and Texas. Journal of the Botanical Research Institute of Texas 7(1):9-20.

Information Compiled By: Robert Sivinski, 2016

Agency Status:
Taxon USFWS State of NM USFS BLM Navajo Nation Natural Heritage NM Global Rank
Viola calcicola Viola calcicola...S3

Photo credits in header Peniocereus greggii var. greggii © T. Todsen,
Lepidospartum burgessii © M. Howard, Argemone pleiacantha ssp. pinnatisecta © R. Sivinski
©2005 New Mexico Rare Plant Technical Council