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|Vol. 6(9), pp. 4-6||The McAllen International Orchid Society Journal||September 2005|
Two plants of a Spiranthes species were initially sighted and photographed on 05 May, 2005 at Lick Creek Park in Grimes County, Texas. At that time, two flowers were taken and preserved in alcohol-glycerin (Ferry specimens Pl#050505-1A&B). Two days later, your editor returned to the site and took several more digital and film photographs and recorded additional observations of the plants and immediate area, and his remarks and tentative conclusions were published in MIOS Journal 6(6): 6-12 (June, 2005). The result was a plethora of tactful, and critical, comments from individuals who shared a common conclusion: that your editor's identification was in error. However, despite unanimity regarding it not being Spiranthes lacera var. gracilis, there were differences of opinion as to what the plants actually are. One source favored its identification as Spiranthes praecox, while others offered information to the effect that it is S. sylvatica. Accordingly, your editor published mea culpas in the following month's issue [MIOS Journal 6(7): 4-7, July, 2005], and continued to study the specimens and photographs at hand, material from his various critics, and the general body of literature pertaining to the species suggested by critics as well as that pertaining to the genus in general.
Spiranthes praecox was originally described as Limordium praecox by Walter (Fl. Car. 221. 1788), and was transferred to the genus Spiranthes by Watson in Gray's Manual, ed. 6, 503. 1890. In 1860, Chapman (Fl. S. U. S. ed. 1, 462) described a specimen as S. tortilis, but in the third edition of the Southern Flora, changed his S. tortilis to S. praecox with the understanding that his material was conspecific with that of Watson. Ames (1905) provides "Contributions Toward a Monograph of the American Species of Spiranthes," and treats the subject in depth. In the Ames key (pp. 124-125), S. praecox is keyed as follows:
Flowers forming a single rank, often second/
Leaves fugacious or persistent, oblong lanceolate to linear lanceolate, some of them exceeding 4.5 cm. in length.
Leaves mostly persistent
Lip oblong, often broadest at the distal end, as long as the sepals and petals or longer, rarely shorter, smooth beneath..............S. praecox
Ames notes Spiranthes praecox as having "leaves mostly persistent," but the plants observed at the Lick Creek Park location exhibited no leaves at flowering.
DNA corroboration was solicited, but your editor was informed the means by which the flowers had been preserved would lead to questions in the validity of any DNA analyses. However, the worker indicated that her DNA work (as yet unpublished) supports S. praecox and S. sylvatica as two distinct species. Hence, this individual was returned to closely studying the available literature, and the photographic and floral material.
The original species description of S. sylvatica has been studied assiduously. For its part, the Latin description was so brief as to be not all that helpful. However, in fairness, it is noted that a great many modern-day formal Latin descriptions (required by Article 36.1 of the International Code of Botanical Nomenclature) are not accompanied by a convenient English translation, and are also (sadly) all-too-brief. However, the Latin and English descriptions of original papers are benchmarks for both hobbyists and professionals, and as such should clearly delineate the species novum from earlier described congeners. That criticism having been voiced, your editor turned to other aspects of the original paper and was pleased to note references from herbarium specimens from Virginia, North Carolina, South Carolina, Florida, Georgia, Louisiana, and Texas. It was somewhat puzzling no specimens were referenced from the intervening states of Alabama and Mississippi, but this is offered only as a casual note; not a criticism of the paper or the herbarium research involved in the author's ultimate decision.
Fig. 1. DSCN #124a. Individual flower, S. sylvatica Digital photo: 07 May, 2005, R. J. Ferry.
What was of great interest to this worker, was the section in Brown's publication of S. sylvatica as a new species, which provided comparisons of S. praecox with the proposed S. sylvatica. In addition to other character differences, particular note was taken of the lateral sepals (S. praecox: appressed, white; S. sylvatica: slightly spreading and arching, green). While the specimens observed and photographed by your editor did not generally display the green coloration, the fresher flowers on the inflorescence were "slightly spreading and arching." The apices of the petals were clearly "turned up and about equal to the turn-down of the lip." Flowers were held horizontally (not "slightly nodding"); and the interior of the lip clearly displays the green veining attributed by Brown to S. sylvatica (Fig. 1). Although coloration, of itself, is generally not a very good taxonomic benchmark in the orchid family, your editor's interest was piqued by a number of inflorescences of S. lacera and S. gracilis, subsequently examined in the Winnipeg, Canada area. These species exhibited the diffused green coloration to varying degrees as in flowers of S. praecox, but, not the green veining attributed to S. sylvatica by Brown.
On the other side of the coin, Pelchat (2005) displays figures (Figs. 2 & 3, p. 9) of flowers (noted as S. praecox) with two differing labellar forms, but bearing the same green veining ascribed to S. sylvatica by Brown. Both were found in 1995, in the now non-existent "Six Mile Creek Housing Development" in Melbourne, Florida. Your editor does not dispute the possibility that hybridization may well be extensive between species of Spiranthes, and it may well be that the future may disclose that what is now described as S. sylvatica may well prove to be a hybrid. On the other hand, the possibility exists that what Pelchat was observing in 1995 was the as-yet-undescribed S. sylvatica.
Fig. 2. DSCN #1244. Partial inflorescence. Digital photo: 07 May, 2005, Lick Creek Park, Grimes County, Texas.
Ultimately, given differences in species personally observed, the indications (verbal) concerning the DNA work, and the absence of clear evidence to the contrary, this worker finds no valid reason to reject Brown's arguments favoring S. sylvatica as a valid species, nor to argue vehemently against the Lick Creek plants as S. sylvatica (Fig. 2).
It would be interesting to self and sib-cross flowers of S. sylvatica under critical conditions, and culture f1 and even self and sib cross f2 specimens. However, this venture would require specialized laboratory and cultural facilities to ensure the isolation and proliferation of the experimental specimens and offspring, and that project could easily exceed five years duration.
This editor is the naturally suspicious sort and retains some reservations, but the weight of evidence comes down on the side of recognizing these plants as S. sylvatica. Hence, this encounter represents a new range extension, both north and west within Texas, for this species, and its encounter in Grimes County represents, of course, a new county for it in Texas.
Ames, O. 1905. Orchidaceae: Illustrations and Studies of the Family Orchidaceae. Fascicle I. Cambridge: The Riverside Press. 156pp.
Brown, P. M. 2004. Wild Orchids of the Southeastern United States, North of Peninsular Florida. 394pp.
Correll, D. S. 1950, 1978. Native Orchids of North America. Stanford, California: Stanford University Press. 399pp.
Fowler, J. A. 2005. Wild Orchids of South Carolina. Columbia, South Carolina: The University of South Carolina Press. 242pp.
International Code of Botanical Nomenclature. 2000. W. Greuter, ed. (et al). Konigstein, Germany: Koeltz Scientific Books. 474pp.
Liggio, J. and Ann Orto Liggio. 1999. Wild Orchids of Texas. Austin, Texas: The University of Texas Press. 228pp.
Luer, C. A. 1972. The Native Orchids of Florida. New York: The New York Botanical Garden 1972. 293pp.
________. 1975. The Native Orchids Of The United States And Canada excluding Florida. New York: The New York Botanical Garden. 361pp.
Pelchat, C. 2005. A Pictorial Monograph of Three Spiranthes Species and Their Hybrids. MIOS Journal 6(7): 8-11 (June, 2005)