Dyschoriste oblongifolia (Michx.) Kuntze

Daniel, Thomas F., 2015, Additional Notes on North American Acanthaceae: Biogeography, Distributions, Taxonomy, Lectotypifications, and Catalog of Species, Proceedings of the California Academy of Sciences 62 (17), pp. 417-432 : 421-422

Dyschoriste oblongifolia (Michx.) Kuntze

UNITED STATES. Louisiana. Natchitoches Parish: Briarwood , near LA 9 and Readhimer [ca. 32°6.92ʹN, 92°59.195ʹW], 6 VI 1969 , R. Thomas et al. 13851 ( NLU).

Of the three species of Dyschoriste Nees that occur in the southeastern United States, D. oblongifolia has the most extensive distribution and bears the largest flowers. Wasshausen (1998) noted the occurrence of this species in Alabama, Florida, Georgia, South Carolina, and Louisiana. Numerous collections from the former four states that conform to D. oblongifolia confirm its presence in each. Occurrence of the species in Louisiana has remained undocumented. Reports or collections from Virginia, Tennessee, and Texas also have been attributed to this species.

Various authors (e.g., Riddell 1852; Long 1970; MacRoberts 1989; Wasshausen 1998) noted the occurrence of this species in Louisiana; however, no documented occurrences were cited or seen. Featherman (1871) noted an occurrence of the species (as Dipteracanthus oblongifolius (Michx.) Chapm. ) from “Farmersville” [= Farmerville] in Union Parish; this was undoubtedly the basis for MacRoberts’ (1989) map, which attributed the species to that parish. The species was not listed for the state by Thomas and Allen (1982), and was subsequently specifically excluded by them ( Thomas and Allen 1996). Irrespective of whether the nineteenth century report of the species from Louisiana is based on an extant collection that has yet to be located or studied, the relatively recent collection noted above conforms to D. oblongifolia and confirms its presence in that state.

Dyschoriste oblongifolia has been noted to occur in Virginia on numerous occasions. Small (1903; as Calophanes oblongifolia (Michx.) D. Don ) indicated that the species occurred from Virginia to Florida. In a monograph of the genus, Kobuski (1928:56) cited Thurber s.n. (GH) as “probably from [the] southeastern portion of the state.” Original data on this collection indicates “Southern States” and “ Virginia,” but lacks both locality and date of collection. Fernald wrote on the specimen that its provenance was doubtful (cf. Fernald 1937: 477, 1945: 63). Fernald (1945) corrected his identification of a collection (Hunnewell 17361) from Frederick County, Virginia from D. oblongifolia to Ruellia humilis Nutt. Gleason (1952) indicated that the species occurred in southeastern Virginia, but that it had not been observed there for many years. A specimen collect- ed in 1841 (Bailey s.n.) at NY, at which herbarium both Small and Gleason worked, is attributed to Virginia. Because the specimen also lacks locality information, its provenance remains doubtful. Uttal (1983) noted that the species was long thought to occur in southeastern Virginia, but that no specimens from the state had come forth. The species was not treated in the recent Flora of Virginia ( Weakley et al. 2012), and its occurrence (even historical) in that state remains both undocumented and doubtful.

A sterile collection from Tennessee (arid hills about Chattanooga, G. Engelmann s.n., 25 Aug 1876, MO) was annotated by R. Hilsenbeck and A. Boyd as D. oblongifolia . Owing primarily to the lack of flowers and fruit , I was unable to associate this specimen with the species or the genus. While it is near the northern limit of the range of the species, it doubtfully pertains to D. oblongifolia .

Durand 18 at PH from an undisclosed locale in Texas appears to represent D. oblongifolia , but because it lacks a specific locale and is out of the known range of the species, its occurrence in that state is treated as suspect and not recognized here. Numerous plants of D. linearis (Torr. & A. Gray) Kuntze from Texas have been erroneously identified as D. oblongifolia . Dyschoriste linearis , a species occurring from south-central Oklahoma to Mexico and common in central Texas ( Daniel 2013), can appear superficially similar to D. oblongifolia . Both species have similarly shaped leaves (commonly oblanceolate to obovate) and relatively long corollas (18–31 mm). They can be distinguished on the basis of the ratio of the calyx lobes to the calyx tube, 2–3 in D. linearis and 3.1–5. 8 in D. oblongifolia .

Thus, occurrences of D. oblongifolia have been documented from Alabama, Florida, Georgia, South Carolina, and Louisiana. The species likely also occurs in Mississippi; however, no collections of it from that state have been located.

AN UNUSUAL FORM OF JUSTICIA AMERICANA FROM LOUISIANA AND TEXAS