Solanum pseudogracile
| Notice: | This page is derived from the original publication listed below, whose author(s) should always be credited. Further contributors may edit and improve the content of this page and, consequently, need to be credited as well (see page history). Any assessment of factual correctness requires a careful review of the original article as well as of subsequent contributions.
If you are uncertain whether your planned contribution is correct or not, we suggest that you use the associated discussion page instead of editing the page directly. This page should be cited as follows (rationale):
Citation formats to copy and paste
BibTeX: @article{Knapp2019PhytoKeys123, RIS/ Endnote: TY - JOUR Wikipedia/ Citizendium: <ref name="Knapp2019PhytoKeys123">{{Citation See also the citation download page at the journal. |
Ordo: Solanales
Familia: Solanaceae
Genus: Solanum
Name
Solanum pseudogracile Heiser, Bot. J. Linn. Soc. 76: 294. 1978 – Wikispecies link – Pensoft Profile
Type
United States of America. North Carolina: Onslow County, N of Surf City, North Carolina Hwy. 210, 16 Jul 1960, C.R. Bell 17061 (holotype: IND [IND-0136007, acc. # 145606]; isotype: IND [IND-0136008, acc. # 145605], NCU [NCU00062742]).
Description
Subwoody annual herb to perennial shrub up to 1.0 m tall, branching at base. Stems terete or with minute spinescent processes, green-grey to straw colour, sparsely to moderately pubescent with simple, appressed, uniseriate eglandular 4–9-celled trichomes, these ca. 0.8 mm long; new growth more densely pubescent. Sympodial units difoliate, not geminate. Leaves simple, (1.3)1.8–8.3(–10.5) cm long, (0.6–)1.1–3.7 cm wide, ovate-lanceolate to narrowly ovate, slightly discolorous, green above and pale grey underneath; adaxial surface sparsely pubescent with appressed translucent, simple, uniseriate trichomes like those on stem, these denser along the veins; abaxial surface more densely pubescent like those of the upper surface evenly across lamina and veins; primary veins 3–5(6) pairs; base attenuate to acute, slightly unequal; margins entire to occasionally shallowly sinuate dentate; apex acuminate to acute; petiole (0.7–)1.0–2.4 cm long, pubescent with simple uniseriate trichomes like those of the stems and leaves. Inflorescences 1.2–2.0 cm long, lateral, internodal, unbranched or rarely forked, then with rhachis 0.4–0.5 mm long, with 3–8 flowers spaced along the rhachis, sparsely pubescent with appressed simple uniseriate trichomes like those on stem; peduncle 1.2–1.8 cm long, straight; pedicels 5–8 mm long, 0.2–0.3 mm in diameter at the base and 0.5–0.6 mm in diameter at the apex, straight and spreading, articulated at the base; pedicel scars spaced ca. 0–1 mm apart. Buds ellipsoid, corolla exserted from the calyx to 2/3 of its length. Flowers 5-merous, all perfect. Calyx tube 1.0–1.5 mm long, the lobes 0.5–1.0 mm long, ca. 1 mm wide, broadly ovate to obovate with obtuse to shortly acute apices, sparsely pubescent with appressed hairs like those on stem but shorter. Corolla 10–12 mm in diameter, deeply stellate, white with a yellow-green central portion near the base, some with darker blackish-purple colouration around the central star, lobed 2/3 to 4/5 to the base, the lobes 4.0–5.0 mm long, 1.6–3.0 mm wide, strongly reflexed at anthesis, later spreading, densely pubescent abaxially with simple uniseriate trichomes like those on stem and leaves but shorter. Stamens equal; filament tube minute; free portion of the filaments 0.6–1.0 mm long, adaxially pubescent with tangled uniseriate 4–6-celled simple trichomes; anthers 2.2–2.6 mm long, 0.5–0.7 mm wide, ellipsoid, yellow, poricidal at the tips, the pores lengthening to slits with age. Ovary globose, glabrous; style 3.5–4.0 mm long, exserted up to (1.0-)2.5 mm beyond the anther cone, densely pubescent with 2–3-celled simple uniseriate trichomes at the base; stigma capitate, minutely papillate, green in live plants. Fruit a globose berry, (4-)8–14 mm in diameter, dull purplish-black at maturity, opaque, the surface of the pericarp matte and somewhat glaucous; fruiting pedicels 7–10 mm long, 0.3–0.4 mm in diameter at the base, (0.6-)0.9–1.0 mm in diameter at the apex, deflexed, becoming woody, pedicels spaced (0)0.5–3.0 mm apart, dropping with mature fruits; fruiting calyx not accrescent, the tube 1.0–1.5 mm long, the lobes 2.5–3.0 mm long, lobes reflexed in fruit. Seeds 20–50(-60) per berry, 1.1–1.3 mm long, 0.8–0.9 mm wide, flattened and tear-drop shaped with a subapical hilum, pale yellow, the surfaces minutely pitted, the testal cells pentagonal in outline. Stone cells absent (very rarely 2). Chromosome number: 2n=2×=24 (Heiser et al. 1965[1]; Heiser et al. 1979[2]).
Distribution
(Figure 41) Solanumpseudogracile is endemic to the southeastern United States of America from the Atlantic coast of the Carolinas to the Gulf Coast in Florida and Alabama. Although we have seen no collections yet, we expect this species to also occur in the Bahamas.
Ecology
Occurring on sand dunes, sandy moist banks and disturbed areas between 0–400 m elevation. Solanumpseudogracile is ecologically distinct from S.americanum in growing mostly on hummocks in salt marches or on sand dunes, as an epiphyte on palm trees, on walls, and among dense hedgerows.
Common names
United States of America. Glowing nightshade (USDA Plants 2017[3]). The common name of Coastal-dune nightshade (NatureServe 2017[4]) attributed to S.gracilius Herter likely refers to S.pseudogracile.
Uses
None recorded.
Preliminary conservation status (IUCN 2017[5])
Least Concern (LC). Solanumpseudogracile is common and weedy in coastal habitats in the southeastern United States. For EOO see Table 6. [NB: the Midwest Plants consortium is not showing locality data in North Carolina because of conservation threat – see http://midwestherbaria.org/portal/collections/individual/index.php?occid=15549149&clid=0]
Discussion
Solanumpseudogracile is a species of the eastern North American coastal plain, and usually occurs in coastal areas not far from the sea. It is very similar to the adventive S.chenopodioides and can be very difficult to distinguish from it. Solanumpseudogracile has longer rectangular to obovate calyx lobes that are rounded to acute at the apex and reflexed in fruit, while S.chenopodioides has short triangular calyx lobes that are acute at the apex and always appressed in fruit. In addition, S.pseudogracile has a longer style that extends (1)2.0–2.5 mm beyond the anther cone, compared to S.chenopodioides where the style is exserted only to 1.5 mm beyond the anther cone. The species differs from S.nigrescens in lacking stone cells or rarely having 2, while S.nigrescens always has 4–13 stone cells per fruit. In the absence of fruit these two species can be very difficult to distinguish; they are widely sympatric along the Gulf Coast of the southern United States of America.
Solanumpseudogracile may be merely a form of S.chenopodioides, with which it shares many characteristics such as appressed white pubescence and absence of stone cells, but further population level work using molecular and other field markers will need to be undertaken. Distinguishing features of these morelloid species often disappear in herbarium specimens (see D’Arcy 1974b[6]), making analysis using herbarium specimens difficult. Nee (pers. comm.) has seen plants he has identified as the two taxa growing together. The Florida plants identified as S.americanumvar.baylisii by D’Arcy (1974b)[6] fit our concept here of S.pseudogracile, while the type of D’Arcy’s variety is a plant of S.chenopodioides collected from New Zealand. Many of the plants identified as S.chenopodioides in the Florida Plant Atlas (http://florida.plantatlas.usf.edu/) are most likely S.pseudogracile.
In describing S.pseudogracileHeiser (1978)[7] cited only IND. There are two sheets of Bell 17061 in IND, one annotated type. We select this sheet (IND-0136007) as the lectotype for S.pseudogracile; the sheets are not numbered sheet 1 and sheet 2 as was done by Heiser for other species in this group (e.g., S.costaricense, S.leonii).
Specimens examined
See Suppl. materials 1 and 3.
Taxon Treatment
- Knapp, S; Barboza, G; Bohs, L; Särkinen, T; 2019: A revision of the Morelloid Clade of Solanum L. (Solanaceae) in North and Central America and the Caribbean PhytoKeys, 123: 1-144. doi
Images
|
Other References
- ↑ Heiser J, Soria J, Burton D (1965) A numerical taxonomic study of Solanum species and hybrids.American Naturalist99(909): 471–488. https://doi.org/10.1086/282392
- ↑ Heiser C, Burton D, Schilling E (1979) Biosystematic and taxometric studies of the Solanumnigrum complex in eastern North America. In: Hawkes J Lester R Skelding A (Eds) The biology and taxonomy of the Solanaceae.Academic Press, London, 513–527.
- ↑ USDA Plants (2017) USDA- NCRS The PLANTS Database National Plant Data Team, Greensboro [http://plants.usda.gov, accessed 26 November 2017].
- ↑ NatureServe (2017) NatureServe Explorer. An online encyclopedia of life [web application] Version 7.1. NatureServe, Arlington [available http://explorer.matureserve.org, accessed 26 Nov 2017]
- ↑ IUCN (2017) Guidelines for Using the IUCN Red List Categories and Criteria. Version 13. Prepared by the Standards and Petitions Subcommittee. http://www.iucnredlist.org/documents/RedListGuidelines.pdf
- ↑ 6.0 6.1 D’Arcy W (1974b) Solanum and its close relatives in Florida.Annals of the Missouri Botanical Garden61(3): 819–867. https://doi.org/10.2307/2395032
- ↑ Heiser C (1978) S.pseudogracile, a new species of Solanum, section Solanum (Maurella). Botanical Journal of the Linnean Society 76: 294. https://doi.org/10.1111/j.1095-8339.1978.tb01497.x
