Solanaceae Source

A global taxonomic resource for the nightshade family

Solanum agrimoniifolium

Citation author: 
Rydberg
Citation: 
Bull. Torrey Bot. Club 51: 154. 1924.
Type: 
Mexico. Chiapas: Cerro del Boquerón, Sep 1913, C. A. Purpus 6977 (holotype: US-567248! [photos: K!, PTIS!]; isotypes: BM!, F! [photo: PTIS!] GH! [Correll neg. 434: BM!, F!, K!, NY, PTIS!, US-567248!], MO! [photo: PTIS!], NY[2]! [photos LL!, PTIS!]).
Last edited by: 
Spooner, D.M.
Written by: 
Spooner, D.M.
Habit: 
Herbaceous tuber-bearing perennials 0.5-2 m tall. Stems 2-13 mm in diameter at base of plant.
Sympodial structure: 
Sympodial units typically 3-6-foliate.
Leaves: 
Pseudostipules to 2-10 mm long, lunate. Leaves odd-pinnate, 14-48 cm long, 10-24 cm wide, finely pubescent adaxially and abaxially; petioles 1-5 cm long; lateral leaflet pairs (3-) 6-7 (-8), subequal or the size of the lateral leaflets diminishing gradually towards the base of the leaf; most distal lateral leaflets 4.5-10.1 cm long, 1.8-2.7 cm wide, narrowly ovate to elliptical, apex acuminate, base oblique, rounded to cuneate, sessile to subsessile with petiolules up to 2m long; terminal leaflet 6.2-12.5 cm long, 1.8-3.9 cm wide, ovate to elliptical, apex acute to acuminate, base attenuate; interjected leaflets 4-31.
Inflorescences: 
Inflorescence a dichasially branched, ebracteate, monochasial or dichasial cyme, 2-3 forked, generally in the distal half of the plant, with 8-38 flowers, all flowers perfect, peduncle 2.8-9.5 cm long; pedicels 15-30 mm long, articulate between the proximal ¼ and the distal ¼.
Flowers: 
Flowers with the calyx 4.5-12.5 mm long, lobes acute to long-attenuate, acumens 0-6 mm long. Corollas 2-3 cm in diameter, rotate, acumens 0-6 mm, edges of corolla flat, not folded dorsally, blue to purple adaxially and abaxially. Anthers 4-5.5 mm long, connate, yellow, apically poricidally dehiscent and often maturing to a short introrse apical slit, filaments 1-4 mm long. Ovary with style 5-8 mm long, exceeding stamens by 2-3 mm, straight, with stigma globose.
Fruits: 
Fruits 2-5 cm long, conical, obtuse to acute at tip, medium green to deep green throughout.
Seeds: 
Seeds from living specimens green-white throughout, ovoid, ca. 2 mm long, with a thick covering of “hair-like” lateral walls of the testal cells that make the seeds mucilaginous when wet. Removal of these hair-like lateral walls by enzyme digestion reveals a honeycomb pattern at their base.
Chromosome number: 

2n = ploidy missing =48 voucher missing = (Spooner & Hijmans 2001)

Distribution: 

Southern Mexico (Chiapas), southeast through Guatemala and central Honduras, 1800-3400 (3800) m; in wet habitats, in organic soils, in full sun to partial shade, often in openings of cloud forests. Common habitats include recently logged or otherwise recently disturbed areas in valleys, streamsides, upland marshes, or roadside ditches.

Phenology: 
Flowering and/or fruiting collections have been made in every month but April and May.
Phylogeny: 

Solanum agrimonifolium belongs to the potato clade of Solanum (Bohs, in press). Spooner and Sytsma (1992) placed S. agrimonifolium on the most terminal clade of section Petota based on chloroplast DNA restriction site data. Spooner et al. (2004) erected the Conicibaccata group to contain S. agrimonifolium, S. longiconicum, S. oxycarpum, and S. woodsonii. All four of these species form a “polyploid ser. Conicibaccata clade” distinguished from the diploid species of the series by chloroplast DNA and morphological data (Castillo and Spooner 1997). These four species are morphologically distinguished (sometimes with difficulty) as a group by conical fruits, leaves with a somewhat parallel-sided morphology (mentioned in the descriptions as lateral leaflet pairs subequal or diminishing gradually towards the base) and narrowly ovate to elliptical leaflets (Spooner et al. 2001). The species evaluated in North and Central America are all 4x(2EBN) (S. longiconicum is not yet evaluated for EBN, and S. woodsonii is not yet evaluated for ploidy and EBN). Some related species traditionally placed in ser. Conicibaccata in South America are also 4x(2EBN), and others are 2x(2EBN) and 6x(4EBN). All species in North and Central America, like related species in South America, generally grow in moist organic soils in upland rain forests.

Commentary: 

Solanum agrimonifolium, like all four species in the Conicibaccata group, is distinguished by conical fruits, leaves with a somewhat parallel-sided morphology (mentioned in the descriptions as lateral leaflet pairs subequal or diminishing gradually towards the base) and narrowly ovate to elliptical leaflets. As with most species from North and Central America, however, it is distinguished from its most similar species (S. longiconicum, S. oxycarpum, and S. woodsonii) only by a series of overlapping character states. Solanum agrimonifolium is distinguished from the above by its highly dissected leaves, with generally 6-7 lateral leaflets and 4-31 interjected leaflets), in contrast to the other species with generally 3-6 lateral leaflets and 0-6 interjected leaflets.

The southernmost records of S. agrimonifolium were collected in Honduras, from Montaña La Tigre, all clustered within a few km of each other. Spooner et al. (2004) were not able to find the plants on our searches there in 2000 and the species may no longer grow in Honduras.

References: 

Spooner, D.M. & K.J. Sytsma 1992. Reexamination of series relationships of Mexican and Central American wild potatoes (Solanum sect. Petota): evidence from chloroplast DNA restriction site variation.
Syst. Bot. 17:432-448.

Castillo-T., R. 1995. Phylogenetic relationships of wild potatoes, Solanum series Conicibaccata (sect. Petota).
Ph.D. Thesis, University of Wisconsin-Madison.

Castillo-T., R., & D.M. Spooner 1997. Phylogenetic relationships of wild potatoes, Solanum series Conicibaccata (sect. Petota).
Syst. Bot. 22: 45-83.

Spooner, D.M., R.G. van den Berg, A. Rivera-Peña, P. Velguth, A. del Rio, & A. Salas 2001. Taxonomy of Mexican and Central American members of Solanum series Conicibaccata (sect. Petota).
Syst. Bot. 26: 743-756.

Spooner, D.M. & R.J. Hijmans 2001. Potato systematics and germplasm collecting, 1989-2000.
Amer. J. Potato Res. 78:237-268; 395.

Spooner, D.M., R.G. van den Berg, A. Rodríguez, J. Bamberg, R.J. Hijmans, & S.I. Lara-Cabrera 2004. Wild potatoes (Solanum section Petota; Solanaceae) of North and Central America.
Syst. Bot. Monog. 68: 1-209 + 9 plates.

Bohs, L. 2005. Major clades in Solanum based on ndhF sequences.
Pp. 27-49 in R. C. Keating, V. C. Hollowell, & T. B. Croat (eds.), A festschrift for William G. D’Arcy: the legacy of a taxonomist. Monographs in Systematic Botany from the Missouri Botanical Garden, Vol. 104. Missouri Botanical Garden Press, St. Louis.

Genetics: 

Chloroplast DNA restriction site data available in: Spooner and Sytsma (1992) and Castillo (1995).

Wed, 2013-11-20 10:57 -- sandy
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith