Solanaceae Source

A global taxonomic resource for the nightshade family

Solanum morelliforme

Primary tabs

Citation author: 
Bitter & Muench
Citation: 
Repert. Spec. Nov. Regni Veg. 12: 154. 1913.
Type: 
Mexico. Chiapas: Gueytepec, in a knothole, Feb 1912, G. Muench s.n. (lectotype: designated by Spooner et al., 2004: GOET-6863!; isolectotypes: GOET [2]!).
Last edited by: 
Spooner, D.M.
Written by: 
Spooner, D.M.
Habit: 
Herbaceous tuber-bearing perennials 0.1-0.6 m tall, herbaceous, epiphytic, commonly on pine and oak trees, growing in leaf mould and moss or more rarely on ground at base of trees. Stems 2-3 mm in diameter at base of plant.
Sympodial structure: 
Sympodial units typically 3-6-foliate.
Leaves: 
Pseudostipules 5-15 mm long, linear to narrowly ovate. Leaves simple, 3-14 cm long, 1.5-4.9 cm wide, elliptic to narrowly ovate, apex acute to acuminate, base attenuate, finely pubescent adaxially and abaxially; petioles 1-4 cm long.
Inflorescences: 
Inflorescence a dichasially branched, ebracteate, monochasial or dichasial cyme, 2-3 forked, generally in the distal half of the plant, with 7-15 flowers, all flowers perfect, peduncle 0.7-2.2 cm long; pedicels 10-15 mm long, articulate between the proximal ¼ and the distal ¼.
Flowers: 
Flowers with the calyx up to 1.5-2 mm long, lobes acute to mucronate, acumens up to 0.5 mm long. Corollas 1.5-2 cm in diameter, stellate, without acumens, edges of corolla flat, not folded dorsally, white with tones of violet. Anthers 4-5.5 mm long, free; yellow, apically poricidally dehiscent and often maturing to a short introrse apical slit, filaments 1-4 mm long. Ovary with style 6-8 mm long, about equaling stamens, straight, with stigma globose.
Fruits: 
Fruits 0.5-0.8 cm in diameter, globose, yellow-green to 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 =24 voucher missing = (Spooner & Hijmans 2001)

Distribution: 

Widespread throughout central Mexico (southern Jalisco to Querétato and Veracruz), south to southeastern and south-central Guatemala, to southern Honduras; 1870-3050 m; growing almost exclusively as an epiphyte on horizontal branches of mature Arbutus, cyprus, elm, juniper, pine, or oak trees, often in moss and organic litter. Occasionally the species is found on the ground in the woods, in rotting wood of fallen trees, or in moss, like its sister taxon S. clarum. Spooner et al. (1998) were unable to locate S. morelliforme at some previously documented localities that had been logged and reforested, and the range of this species may have been reduced by deforestation. The southernmost record of S. morelliforme, Molina & Molina 26100, was collected in Honduras in 1961, the only record for that country. Antonio Molina (EAP) kindly led Spooner and collaborators back to the exact spots where he originally collected it in small valleys off the main road from Tegucigalpa to Lapaterique. One of these was at a place called Las Tablas at 1600 m, at 14º03.95’N, 87º22.73’W, and the other at Quebrada Honda, at 1610 m, at 14º03’56”N, 87º24’44”W. The species was no longer present in this area and Spooner et al. (2004) could not find it in other nearby sites.

Phenology: 
Flowering and fruiting July through October.
Phylogeny: 

Solanum morelliforme belongs to the potato clade of Solanum (Bohs, in press). Spooner and Sytsma (1992) placed S. morelliforme and all other North and Central American diploids (exclusive of S. bulbocastanum, S. cardiophyllum, and S. verrucosum) in the basal “clade 1” of section Petota based on chloroplast DNA restriction site data. Spooner et al. (2004) placed S. clarum and S. morelliforme in the Morelliforme group based on morphological and AFLP data (Lara-Cabrera and Spooner, in press a,b). Hawkes (1956) erected Solanum ser. Morelliformia to accommodate the species S. morelliforme, and Correll (1962) described Solanum ser. Clara to accommodate the species S. clarum. Correll (1962) and Bukasov (1978) maintained this taxonomy but Hawkes (1963, 1990) placed S. clarum and S. bulbocastanum into ser. Bulbocastanum while maintaining a monotypic ser. Morelliformia (see Plate 1 of Spooner et al., 2004). Solanum clarum and S. morelliforme form a clade according to cpDNA data (Spooner and Sytsma 1992). They occur in similar habitats; S. morelliforme is an epiphyte, and S. clarum rarely grows as an epiphyte but more commonly in the shade of trees in moss in epiphytic-like conditions. The species can be crossed with each other, but with great difficulty, and the hybrids exhibit chromosomal structural differences and sterility in the F2 generation (Marks 1968). Marks (1969) demonstrated by pachytene analysis that the species share characteristic large telochromomeres (although on different chromosomes) unknown in the rest of sect. Petota. Nee (1999) was the first to ally both species to ser. Morelliformia, and Spooner et al. (2004) recognized them under the informal Morelliforme group.

Commentary: 

Solanum morelliforme is very distinctive with its simple leaves and relatively small stature (stems 2-3 mm wide at base, 0.1-0.5 m tall); see discussion under S. clarum for its distinction from the other simple-leaved species S. bulbocastanum and S. morelliforme. It usually grows as an epiphyte, in contrast to its sister taxon S. clarum that grows on the ground in epiphytic-like conditions in moss, or rarely as an epiphyte.

Bitter (1913) cited Muench s.n. as the type collection but not the herbarium of deposition. His indicated that type material had fruits but no flowers, and that he was cultivating the species from seeds taken from these specimens. GOET has four sheets with type locality data. Three of these are in fruit, and we chose one as the lectotype. The forth specimen has flowers and clearly was cultivated later; thus it is not considered type material.

References: 

Lara-Cabrera, S. & D.M. Spooner Taxonomy of Mexican diploid wild potato (Solanum sect. Petota) species: AFLP data.
Plant Syst. Evol.

Lara-Cabrera, S. & D.M. Spooner Taxonomy of Mexican diploid wild potato (Solanum sect. Petota) species: morphological and microsatellite data.
Monogr. Syst. Bot., Missouri Bot. Gard.

Bitter, G. 1912. Solana nova vel minus cognita, V, VI, IX, X, XI.
Repert. Spec. Nov. Regni Veg. 11: 349-394, 431-473, 12: 1-10, 49-90, 136-162.

Hawkes, J.G. 1956. A revision of the tuber-bearing Solanums.
Rep. Scott. Pl. Breed. Stn. 1956: 37-109.

Correll, D.S. 1962. The potato and its wild relatives.
Contr. Texas Res. Found., Bot. Stud. 4: 1-606.

Hawkes, J.G. 1963. A revision of the tuber-bearing Solanums. II.
Scott. Pl. Breed. Sta. Rec. 1963: 76-181.

Marks, G.E. 1968. Structural hybridity in a tuberous Solanum hybrid.
Canad. J. Genet. Cytol. 10: 18-23.

Marks, G.E. 1969. The pachytene chromosomes of S. clarum.
Caryologia 22: 161-167.

Hawkes, J.G. 1990. The potato: evolution, biodiversity and genetic resources.
Oxford: Belhaven Press.

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.

Spooner, D.M., R.G. van den Berg, & J.B. Bamberg 1995. Examination of species boundaries of Solanum series Demissa and potentially related species in series Acaulia and series Tuberosa (sect. Petota).
Syst. Bot. 20: 295-314.

Spooner, D.M., R. Hoekstra, R.G. van den Berg, & V. Martínez 1998. Solanum sect. Petota in Guatemala: taxonomy and genetic resources.
Amer. J. Potato Res. 75:3-17.

Nee, M. 1999. Synopsis of Solanum in the New World.
Pp. 285–333 in M. Nee, D. E. Symon, R. N. Lester & J. P. Jessop (eds.), Solanaceae IV: Advances in Biology and Utilization. Royal Botanic Gardens, Kew.

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

Lara-Cabrera, S.I. 2001. Taxonomy of Mexican diploid wild potato (Solanum sect. Petota) species: a morphological and molecular study.
Ph.D. Thesis, Plant Breeding and Plant Genetics Program, University of Wisconsin-Madison.

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). AFLP, morphological, and microsatellite data listed in: Lara-Cabrera (2001).

Taxonomic name: 
Solanum morelliforme (Solanaceae)
Wed, 2013-11-20 11:01 -- 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