Griffiths, Annual Report of the Missouri Botanical Garden 21: 166, 1910
Holotype; Herbarium; Herbarium; Painting (Mary Emily Eaton); Painting (Mary Emily Eaton)
Original Description
What is Opuntia xanthoglochia?
Opuntia xanthoglochia is a pricklypear cactus found in central Texas east of Austin, although it may range into other areas.
Details
O. xanthoglochia resembles O. macrorhiza. The plant is prostrate to 20-30 cm tall. Large plants may be 1.0 m across. The cladodes are oval or obovate and may be more or less pointed at both ends or round, or they may even be subcircular. Cladodes may be 10 cm across and up to 12(15) cm long. Areoles are raised. O. xanthoglochia typically has yellowish glochids, sometimes numerous and prominent, up to 1 cm long.
The flowers are lemon yellow with red or brownish-red centers, about 7 cm in diameter. However, flowers are occasionally variable, sometimes with no red, other times with excess red or even brownish tints. Other times, the red is confined to the mid-rib of the tepals. Filaments are greenish, and the style and stigma are white or pale yellowish. The ovary is long and slim.
O. xanthoglochia is diploid, whereas O. macrorhiza is tetraploid.
Other Notes
Perhaps O. xanthoglochia is a diploid form of O. macrorhiza s.l.
Read more about the ploidy of O. xanthoglochia.
For more information, see:
Majure L.C., Judd W.S., Soltis, P.S., and Soltis, D.E. (2012a) Cytogeography of the Humifusa clade of Opuntia s.s. Mill. 1754 (Cactaceae, Opuntioideae, Opuntieae): correlations with Pleistocene refugia and morphological traits in a polyploid complex, Comparative Cytogenetics, 6:53.
Opuntia xanthoglochia, Bastrop Co, TX, Jerry McNulty
Opuntia xanthoglochia, Bastrop Co, TX, Jerry McNulty
Opuntia xanthoglochia, ca. 1910
Opuntia xanthoglochia, garden plant, Ben Udall
Opuntia xanthoglochia, Guadalupe Co, TX, Jerry McNulty
Opuntia xanthoglochia, Guadalupe Co, TX, Jerry McNulty
Opuntia xanthoglochia, Guadalupe Co, TX, Jerry McNulty
Opuntia xanthoglochia, Jerry McNulty
Opuntia xanthoglochia, LaGrange, Texas
Opuntia xanthoglochia, LaGrange, Texas
Opuntia xanthoglochia, yellow glochids, garden plant, Jacen A Myers
Opuntia xanthoglochia, yellow glochids, new pad with leaves, Jacen A Myers
I’ve seen O. xanthoglochia in Texas, just west of Austin.
Tom,
How was it growing. I mean was it in brush or grassland, or maybe with junipers?