Sapindus saponaria Linnaeus (1753: 367)

Franck, Alan R., 2024, Revision of Sapindus sect. Sapindus (Sapindeae, Sapindoideae, Sapindaceae), including the description of three new species, Phytotaxa 648 (1), pp. 1-71 : 34-36

8. Sapindus saponaria Linnaeus (1753: 367) . ≡ Sapindus alatus Salisbury (1796: 280) , nom. illeg. Lectotype (designated by Pennington in Jarvis et al. 1993):—Plukenet, Phytographia t. 217, fig. 7. 1692. Epitype (designated here):—

JAMAICA. St. Thomas : near Rocky Point Village, 3 January 1973, G. R. Proctor 33094 (epitype, IJ000004756 !; isoepitypes,

NY 01308056!, U 1598763!).

= Sapindus rigidus Miller (1768) .

≡ Sapindus saponaria L. forma inaequalis (DC.) Radlk. subforma rigidus (Mill.) Radlkofer (1900: 517) .

Lectotype (designated here, or perhaps holotype):— MEXICO. Veracruz: Vera Cruz, W. Houston s.n. (lectotype, BM000838022 !).

= Cupania saponarioides Swartz (1788: 62) .

Lectotype (designated here, or perhaps holotype):— JAMAICA. O. Swartz s.n. (S-R-1326).

= Sapindus forsythii de Candolle (1824: 607) .

Lectotype (designated by Leenhouts 1994, or perhaps holotype):— GRENADA. A. Alexander ex W. Forsyth s.n. (lectotype, G00211893 ).

= Sapindus stenopterus de Candolle (1824: 607) .

Lectotype (designated here, or perhaps holotype):— Santo Domingo, [1819-1820], C. L. G. Bertero s.n. (lectotype, G00211892 ).

= Sapindus inaequalis de Candolle (1824: 608) .

≡ Sapindus saponaria forma inaequalis (DC.) Radlkofer (1898: 402) .

Lectotype (designated here):— GUADELOUPE. [1816-1818], C. L. G. Bertero s.n. (lectotype, G00211955 ).

= Sapindus divaricatus de Saint-Hilaire (1828: 390) .

Type: BRAZIL. Minas Gerais: prope Sabará , January 1804, F. B . Sieber ex J. C. G . Hoffmansegg s.n. (probable holotype [2 sheets], B - W 07742 -01 0, B - W 07742 -02 0) .

= Sapindus peruvianus Walpers (1843: 312) .

Type: not indicated.

= Sapindus peruvianus Walpers var. dombeyanus Walpers (1843: 312) .

Type: PERU. Dombey 637 (not located).

= Sapindus peruvianus Walpers var. meyenianus Walpers (1843: 312) .

Type: PERU. Meyen s.n. (not located).

= Sapindus saponaria L. forma genuinus Radlkofer (1900: 517) .

Type: not indicated.

= Sapindus grandifolius Lippold (1974: 628 , f. 13), nom. illeg. (non S. grandifolius Engelh. ).

≡ Sapindus lippoldii Turner (2014: 308) .

Type: CUBA: Guantánamo: Montes Cagüines, Imías , September 1938, Matos LS18561 (holotype, HAC [ex SV]) .

Etymology:—From the Latin sapo for soap.

Description: —Tree, to 13 m tall. Petiole 1–8(9) cm long, glabrous to sparsely pubescent, pale yellow to green, unwinged or wing to 5 mm wide on one side; rachis glabrous to sparsely pubescent, unwinged or wing to 6 mm wide on one side; leaflets 4–12(14); petiolule 0–5(9) mm long, glabrous to moderately pubescent; leaflet blade lanceolate, ovate, elliptic, to obovate, strongly asymmetric to more or less symmetric, straight to falcate, the apex obtuse to acuminate, 3–19 cm long, 1.5–7.6 cm wide, 1.6–3.5(5) times longer than wide, adaxially drying pale green, green, pale brownish green, glabrous or sparsely pubescent along the midrib, the midrib pale green to pale yellow, glabrous to densely pubescent, at mid-blade the ridge 0.1–0.3 mm wide, 0.1–0.3 mm high to occasionally nearly flat or sunken, the blade not sunken or scarcely sunken along the midrib, secondary veins pale green to pale yellow, discolorous to nearly concolorous with the blade surface, tertiary venation prominulous, nearly concolorous with the blade surface, quaternary venation prominulous to obscure, nearly concolorous with the blade surface, abaxially drying pale green, glabrous to densely pubescent or short-pilose, midrib pale yellow, glabrous to densely pubescent, secondary veins pale yellow, secondary veins pale green to pale yellow, discolorous to nearly concolorous with the blade surface, tertiary venation prominulous, nearly concolorous with the blade surface, quaternary venation prominulous to obscure, nearly concolorous with the blade surface; exudates clear, inconspicuous to conspicuous abaxially on the blade surface. Petal blade ovate, without appendages, the base sometimes truncate to subsagittate with inrolled corners. Mature mericarp subglobose, 14–23 mm wide, pericarp 0.2–2 mm wide, seed 11–15 mm wide.

Distribution, habitat, and phenology:—Caribbean Islands, French Polynesia, Mexico, Central America, South America, and USA (Florida) ( Fig. 3 ); 0–2130 m. Flowering year round.

Notes:— Sapindus saponaria is a wide-ranging species characterized by its leaflet blades usually drying green with pale yellow midribs and secondary veins, the reticulate veins often prominulous to obscure and lightly discolorous to nearly concolorous with the blade surface, the rachis winged to unwinged, petals lacking appendages, mature mericarps 14–23 mm wide, seed 11–15 mm wide, hypogeal and cryptocotylar germination ( Fermond 1860a, 1860b, Duke 1965, das Neves et al. 2018, Wilder 2022), and its primarily fall-winter flowering season. This species frequently has conspicuous microscopic glandular foveolae on the leaflet undersides, and the exudate is mostly clear or colorless. The distribution of S. saponaria indicates an intolerance to freezing temperatures.

The circumscription and distribution of S. saponaria here is much narrower than earlier treatments. In some historical concepts (e.g. Standley 1923, Leenhouts 1994, Wagner et al. 1999, Xia & Gadek 2007, Acevedo-Rodríguez 2014), S. saponaria was effectively the sole representative of sect. Sapindus . All other species of sect. Sapindus recognized here have, at one time or another, been treated as synonyms or infraspecific taxa of S. saponaria ( S. balicus , S. drummondii , S. marginatus , S. mukorossi , S. oocarpus , S. thurstonii , S. tricarpa , and S. vitiensis ) or were hidden, undescribed species ( S. motu-koita , S. marikuru , or S. standleyi ). As far as is known, S. saponaria is allopatric from all of the aforementioned species, except the ranges of S. drummondii and S. standleyi may overlap with S. saponaria . Radlkofer (1932a, 1932b) recognized that S. balicus , S. drummondii , S. marginatus , S. mukorossi , S. oocarpus , and S. vitiensis were distinct from S. saponaria .

Radlkofer (1932b) distinguished three forms of S. saponaria , two ( f. genuinus and f. inaequalis ) which are here referred to S. saponaria subsp. saponaria . The third form ( f. microcarpus ) was applied by Radlkofer to plants of French Polynesia, Hawaii (specifically Remy 566), Papua New Guinea, Philippines, Pitcairn Islands, and Rapa Nui. Here the plants of French Polynesia, the Cook Islands, and Hawaii (specifically Remy 566) are referred to S. saponaria subsp. jardinianus , the plants of Papua New Guinea are described as S. motu-koita , the plants of the Philippines are recognized as S. tricarpus , those of the Pitcairn Islands are referred to S. saponaria subsp. saponaria , and the plants of Rapa Nui are described as S. marikuru .

The Plukenet (1692) illustration is the lectotype of S. saponaria , but it is bereft of much morphological detail or information concerning its provenance. In the Sloane herbarium, there are specimens of Sapindus in the Plukenet folios 97: 127 and 101: 122 which may have been used for the illustration. Yet, there is no strong resemblance between the Plukenet illustration and the specimens in the folios, although the leaflet number, leaflet arrangement, and narrowly winged rachis are similar. Fruits and a stem are depicted in the illustration, but these are not present in the folio specimens. No provenance is given but other materials in the folios are putatively from Barbados and Jamaica ( Dandy 1958). The lectotype illustration cannot be properly identified using the diagnostic characters set forth here, and it lacks clear provenance. The lectotype is thus demonstrably ambiguous. Therefore, an epitype is here designated ( Sennikov 2022) from Jamaica which is consistent with the protologue and related texts ( Plukenet 1696, Linnaeus 1738, 1762, Aiton 1811). In the protologue of S. saponaria, Linnaeus also cited Commelin (1697: 183, fig. 94) which is evidently Melicoccus bijugatus Jacquin (1760: 19) .

The specimens at LINN were considered types by Croat (1977: 504), but they are not original material ( Radlkofer 1878: 364, Wijnands 1983: 185). Howard (1989) apparently considered material from Hort. Cliffortianus to be the type, based on Wijnands (1983: 185). However, it is not an effective typification because it cannot be assumed that one gathering was selected as type by Howard as there are two sheets in Hortus Cliffortianus (Jarvis, pers. comm.). Notably, one is in a decorative vase and the other is not. The source of Clifford’s material can doubtfully be ascertained ( Wijnands & Heniger 1991).

A sterile, cultivated specimen from Indonesia (Chase 2136, K) identified as S. saponaria was sequenced using the angiosperms353 universal probe set ( Buerki et al. 2021, Joyce et al. 2023) but probably it does not belong to S. saponaria s.str. and should be re-evaluated.

Figures

FIGURE 3. Native distribution of cited specimens of Sapindus in the Americas and eastern Oceania (cultivated or naturalized occurrences are not mapped). Longer names of some taxa are abbreviated, i.e. S. drummondii var. drummondii (abbreviated as drum. var. drum.), S. drummondii var. glabratus (drum. var. glabratus), S. saponaria subsp. jardinianus (sap. subsp. jard.), and S. saponaria subsp. saponaria (sap. subsp. sap.), The symbol for the occurrence of S. saponaria subsp. jardinianus in Hawaii is placed beside Hawaii on the map.