Thursday, April 29, 2010

Where is the type population of Lewisia congdonii?

Basionym: Oreobroma congdonii Rydb., N. Amer. Fl. 21(4): 322. 1932.

Protologue: "Type collected on the Hennesay [sic] Ranch, Mariposa County, California, May 31, 1883, Congdon (Dudley herb. Stanford Univ. 45334)."

The type and UC/JEPS isotype specimens are labeled "Hennesey Trail", which indicates that the specimen was taken in the ascent from Henness Ranch, located on the floor of the canyon in present day El Portal, up the south rim of the canyon. The Henness Trail appears on the 1897 edition of the Yosemite 30-minute USGS quadrangle, but is not named until the reprinted 1929 edition. The trail ascended the canyon wall and the exact station of the type collection has never been relocated.

The MIN Isotype is labeled "Hite's Cove and Yosemite Trail"

At one time, Hennesey Trail was a major but secondary route for visitors to gain access into Yosemite Valley. The trail is shown on the 30-minute USGS quadrangles: on the 1887 first editon, and on other editions issued between 1903 and 1911, the trail is depicted, but not named. On the 1923 edition, the trail name appears. On the 1956 first edition of the 15-minute quadrangle, the trail is no longer mapped. In that era, visitors using the Yosemite Valley Railroad, which opened in 1907, would come to El Portal and thence would be taken by mule train to Yosemite Valley via the Hennesey Trail, and that fact would be consistent with the trail having been mapped with a placename on the 1923 map.

Congdon, being a lawyer traveling through the region, is well documented by his trail of specimens to have visited much of Mariposa County, and no doubt would have rode horseback up the trail into the Valley via that route. Congdon's labels for that period bear out his route, a few examples:

May 31, 1883
MIN235214 Iris hartwegii
MIN235935 Hosackia crassifolia
MIN236268 Draperia stystyla Hite's Cove and Yosemite Trail
MIN237456 Clarkia heterandra Yosemite Trail
MIN238487 Calyptridium umbellatum Hite's Cove and Yosemite Trail and Yosemite Valley.

June 1, 1883 – pretty clearly, Congdon went into Yosemite Valley, based on these labels
MIN231619, MIN237891, MIN238314, MIN238976 Yosemite Valley
MIN235470 Yosemite Trail
MIN236100 River Trail to Yosemite Valley
MIN237643 Yosemite Valley and Glacier Point
MIN238521 Cascades, Yosemite Valley
MIN238593 Yosemite Trail, Merced River,
MIN238976 Yosemite Valley
MIN239486 Cascades and Yosemite Valley

Propositon: on this basis, the type station for Lewisia congdonii is probably NOT the well know population on the rocks at the base of Pigeon Gulch, along present day Highway 140. It is more probable that the type specimen was collected along the ascent route of the Hennessay Trail, which would suggest that another, presently uncodumented population is located on the steep, north facing wall of the Merced Canyon, perhaps even near Chinquipin Falls, on the present day Yosemite National Park boundary.

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