From Plant Press, Vol. 7, No. 4 from October 2004.
By John Boggan
A new gem—or rather, an old gem that went unrecognized for half a century—has been discovered in the U.S. National Herbarium: a type specimen of the famous “living fossil”
Metasequoia glyptostroboides. This species, described by Chinese botanists H.H. Hu and W.C. Cheng in 1948, caused an international sensation in the 1940s when it was identified as a living representative of a genus previously known only from fossils (Science 107: 140. 1948; Arnoldia 8: 1‑8. 1948).
In October 2004 the Department’s Type Specimen Register received a specimen of Metasequoia glyptostroboides that had recently been annotated as a syntype by visiting Brooklyn Botanic Garden botanist Jinshuang Ma. The specimen, C.T. Hwa 2, collected in China on 12 September 1947, was sent to the National Herbarium from the Arnold Arboretum sometime in the 1940s. According to a note on the label by E.D. Merrill it was “doubtless collected from the original type tree,” but there was otherwise no indication on the specimen that it was a type specimen. It was filed in the general herbarium, where it languished for over 50 years until discovered by Ma in 2003.
“New” types of old species regularly turn up in the general herbarium, but it seemed odd that a type specimen of such a famous species could go for so long without being recognized. Even more confusing, according to the Missouri Botanical Garden’s Tropicos Web site, the type collection is C.Y. Hsueh 5, collected 20 February 1946, with the holotype deposited in the herbarium of the Arnold Arboretum. According to the Harvard University Herbaria Web site, all specimens at the Arnold Arboretum are syntypes.
Because of the discrepancy between Ma’s annotation and Tropicos, it seemed worth checking the original description of the species to confirm it one way or the other. Sure enough, among several collections cited in Hu and Cheng’s original description (Bulletin of the Fan Memorial Institute of Biology 1: 153‑163. 1948), two were explicitly indicated as types: “C.J. Hsueh no. 5, type in flowers and cones without foliage shoots, Feb. 20, 1946” and “...same locality, same tree, C.T. Hwa no. 2, type in cones with foliage shoots, Sept. 12, 1947.” The US collection clearly matches the second specimen cited as “type.” Since two collections made by different collectors on different dates (albeit from the same tree) are indicated as “type” both have equal status as syntypes. The specimens at the Arnold Arboretum are thus isosyntypes, one of them perhaps being a lectotype at best (although it is unclear whether a lectotype has ever been designated, either explicitly or effectively).
An interesting footnote is that the original tree from which the type specimens were collected is still living and a recent photograph of the tree accompanied an article about this species in Taxon (52: 585‑588. 2003). More information on the botanical history of this species, including an extensive bibliography, is available at Jinshuang Ma’s Web site at <http://metasequoia.org>.
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