Griseliniaceae Families & Genera of Vascular Plants
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Griseliniaceae Griseliniaceae Takh., Sist. Magnol. 209 (1987). M.O. DILLON Evergreen, dioecious trees, erect shrubs or trail- with copious endosperm; embryo minute, ing or vining, New Zealand species are epiphytes straight; n ¼ 18. or hemi-epiphytes, aerial roots enlarging upon One genus with seven spp., trans-Pacific dis- contact with the ground; stems erect to scandent junct (Argentina, Brazil, Chile, New Zealand). or climbing, glabrous to hispidulose, rarely winged. Leaves simple, evergreen, entire to den- VEGETATIVE MORPHOLOGY AND ANATOMY. All mem- tate or dentate-spinose, alternate and distichous bers of the family are woody, ranging from small or subopposite; subsessile or petiolate; petioles trees or large shrubs reaching a maximum height rugulose, glabrous or hispidulose, exstipulate, of 10–20 m to shrubs seldom over 2 m. The the bases dilated and subsheathing; blades coria- growth habit is typically erect and self-support- ceous, basally oblique to equal, apically rounded ing, but epiphytic, hemi-epiphytic, and climbing to acuminate, abaxial surface penninerved or habits have been recorded (Dawson 1966). Leaves prominently 3–5-nerved from near the base, are evergreen, leathery and often shining. Sto- reticulate, minutely pellucid-punctate, adaxial mata are generally confined to the abaxial surface surface smooth, drying rugulose, nitid, margins of the leaves and encyclocytic. Mucilage is gener- revolute or plane, strictly entire to dentate or ated as epistomatal plugs in New Zealand species, spinose, occasionally subentire with only the but are absent in the one South American species apex minutely 2–3-fid. Inflorescences racemose investigated (Westhoff et al. 2009). An adaxial to paniculate, terminal or axillary, subglabrous hypodermis is present, the mesophyll contains to hispidulose or glandular, drying nigrescent; sclerenchymatous idioblasts, and minor leaf bracts and bracteoles caducous. Flowers unisex- veins are without phloem transfer cells. Secretory ual, actinomorphic, 5-merous; sepals free, val- cavities are absent, a cork cambium is present, vate, squamellate, margins ciliolate to glabrous, nodes are tri-lacunar or multi-lacunar. Secondary occasionally caducous; petals 5, free, occasionally thickening develops from a conventional cambial absent, subimbricate, oblong to ovate, reflexed to ring, the xylem contains vessels with horizontal, patent at anthesis, caducous, margins ciliolate to scalariform end-walls, fibers with bordered pits, glabrous; stamens 5, antisepalous, filaments erect, and the wood parenchyma is apotracheal (Li and attached outside of lobulate epigynous disc, ovary Chao 1954; Noshiro and Baas 1998). The effect of remnants obscure; anthers dithecate, tetraspor- vesicular-arbuscular mycorrhizas on the growth angiate, dorsifixed, dehiscence longitudinal; sta- of Griselinia littoralis has been investigated and minodia sometimes present in female flowers; shown to increase branching in the root system gynoecium 3-carpellate, syncarpous, ovary infe- (Baylis 1958). rior, trilocular in upper part, unilocular in lower part; styles 2 to 3 or rarely 4, simple, terminal, free INFLORESCENCES. The flowers are arranged in to connate basally, persistent, subulate, divergent open, racemose to paniculate inflorescences or recurved, placentation apical, one pendulous which are borne either terminally or axillary on ovule, anatropous. Fruit 1-locular, fleshy, baccate branchlets. The peduncles are typically subglab- or coriaceous, drupaceous, oval to oblong, gla- rous to hispidulose or glandular, nigrescent; brous to hispidulose-puberulent; 1-seeded. Seeds bracts and bracteoles are caducous. # Springer International Publishing AG, part of Springer Nature 2018 505 J.W. Kadereit, V. Bittrich (eds.), Flowering Plants. Eudicots, The Families and Genera of Vascular Plants 15, https://doi.org/10.1007/978-3-319-93605-5_7 506 M.O. Dillon FLORAL MORPHOLOGY AND ANATOMY. Flowers are PHYTOCHEMISTRY. Jensen and Nielsen (1980) dimorphic, minute, rarely more than 5 mm in investigated five Griselinia species and isolated diameter. The staminate flowers have a campan- the iridoid glucoside, griselinoside, from G. littor- ulate hypanthium and are always petaliferous; alis, G. lucida, G. ruscifolia, and confirmed that ovary remnants obscure; epigynous disc nitid iridoids are elaborated in both New Zealand and and producing nectar. The petals are yellow to South American species. The occurrence of grise- greenish-yellow, reflexed at anthesis, and quickly linoside in Aralidium, Torricellia and Griselinia caducous. Anthers are opposite the sepals and suggests affinities; however, the same compound alternating with the petals. The pistillate flowers was also isolated from Verbena (Damtoft et al. also have a hypanthium and in a few species do 1983). Reports indicate that the family is not not have petals (G. lucida). Rudiments of a single cyanogenic and lacks proanthocyanidins and whorl of stamens (staminodia) are found in the ellagic acid (Watson and Dallwitz 1992). Petrose- female flowers of New Zealand species (G. littor- linic acid has been isolated and is present as a alis and G. lucida). The epigynous disc is not major component in many species of Apiaceae unlike that found in Araliaceae and trans-sepal and Araliaceae (Breuer et al. 1987). bundles are present in the ovary (Eyde 1964). Nectar production has not been recorded. Ovary SYSTEMATICS AND AFFINITIES. The family is mono- of three carpels (Kubitzki 1963), trilocular in generic with the seven species of Griselinia. The upper part, unilocular in lower part, with 1 pen- history of familial placement has been complex. dulous, anatropous ovule. Early accounts suggested placement in families such as Euphorbiaceae and Juglandaceae (see EMBRYOLOGY. Ovule morphology has only been Taubert 1892). Endlicher (1850) placed Griselinia investigated in one species and the ovules were in the Araliaceae and Hooker (1867) was the first found to be unitegmic and crassinucellate (Phi- to position it as a member of the Cornaceae. lipson 1977). Taubert (1892) accepted the placement in the Cornaceae and established two sections, Decostea POLLEN MORPHOLOGY. Pollen shed as single grains. Taub. and Griselinia (“Eugriselinia” Taub.). Pollen grains are 3-aperturate; colporate, ellipsoi- Wangerin (1910) in his treatment of the Corna- dal, and with a complete tectum with striate sur- ceae placed Griselinia in tribe Griselinieae Wan- face (Ferguson and Hideux 1978; Tseng 1980). gerin where it was grouped with Melanophylla. Images of Griselinia pollen are available at Austra- Philipson (1967) was the first worker to question lian Pollen and Spore Atlas (APSA 2007). the placement of Griselinia in the Cornaceae, contending that it shared many features with the KARYOLOGY. Only one reported chromosome Araliaceae and Escalloniaceae, and differed from count of n ¼ 18 exists for the family (Federov the Cornaceae by the alternate arrangement of the 1969). leaves, nodal anatomy, the presence of a hypoder- mis below the upper epidermis of leaves, ency- REPRODUCTIVE SYSTEMS AND POLLINATION. All mem- clocytic stomata, the presence of spiral bers of the family are dioecious. The gynoecium thickenings in both vessels and fibers, imbricate of staminate flowers is obscure, but rarely rudi- petals, free or only shortly connate stylodia, a mentary stamens are found in the pistillate usually 1-locular ovary, and baccate fruits. Takh- flowers. Griselinia littoralis is reported to be tajan (1980) treated Griselinia as a monogeneric wind-pollinated; however, insect pollination family and allied it with Garrya (Garryaceae). probably is the most common mode of pollina- Takhtajan (1987) proposed the valid familial tion when nectar is present (Percival 1961). name, since Cunningham’s (1791–1839) pub- lished name for the father and son team of Johann FRUIT,SEED,DISPERSAL. The presence of small Reinhold Forster (1729–1798) and Johann Georg (<10 mm long, 5 mm in diameter), fleshy, red Adam Forster (1754–1794) in the Annuals of Nat- to purple fruits may suggest some type of animal ural History was a typographic error (Earp 2013). mediated dispersal (Takhtajan 2000). Testa prob- Earp (2014) has submitted a proposal to conserve ably many-layered, outer two (and esp. third) the generic name. Takhtajan (1997) established layers with thickened walls. the order Griseliniales for the family, while Griseliniaceae 507 Thorne (1968), Dahlgren (1980), and Cronquist greatly, from mesic, evergreen rain forest environ- (1981) considered it an anomalous member of the ments of austral Chile (sea level–1300 m) to dry Cornaceae. Thorne (1992, 2001) placed it as a coastal quebradas of the Atacama Desert in north- monogeneric family with relationships outside ern Chile (400 m). Southern Brazilian populations of the Cornales. Eyde (1987) also recognized are found in Araucaria forests and range north to that Griselinia was misplaced in the Cornaceae remnants of the Atlantic coastal forest (400–2700 and suggested familial rank. m). The New Zealand species are distributed from Xiang et al. (1993) and Xiang and Soltis near-ocean sites to montane forests of North and (1998) examined rbcL sequence data and sug- South Islands. One species, G. littoralis,isintro- gested Griselinia be removed from the Cornaceae duced in Australia as an ornamental and natura- and grouped it with Aralidium and Torricellia lized in Tasmania (Baker 2009). (both Torricelliaceae) and more distantly with Aralia (Araliaceae), Pittosporum (Pittospora- ceae), and Sanicula (Apiaceae). Plunkett et al. Only one