96 DROSERACEAE ¹

Dennis I Morris,^† Miguel F de Salas ²

Small annual or perennial, carnivorous herbs; roots fibrous, the primary root often reduced; tubers or small rhizomes produced in some species. Leaves spiral, sometimes whorled, often in a basal rosette; stipules present or absent; lamina either modified as active traps (not in Tas.) or with mucilage-tipped often irritable insect trapping hairs. Inflorescence terminal or axillary. Flowers bisexual, actinomorphic, hypogynous. Sepals (4)5(–8), shortly connate at the base. Petals as many as the sepals, free or basally connate. Stamens (4)5(10–20), free or basally connate, alternating with petals, anthers bilocular. Carpels 3–5; ovary superior, unilocular, placentation parietal; ovules many; styles as many as the carpels, free or united at the base, often deeply divided. Fruit a loculicidal capsule enclosed in the persistent calyx. Seeds many, small, endospermic.

A family of 3 genera with about 160 species in temperate and tropical regions of both hemispheres with Australia being a major centre of diversity. 2 genera are represented by single species: Aldrovanda vesiculosa L. (NE Australia, Eurasia) and Dionaea muscipula Ellis (Venus’ Fly-trap; SE USA). Droseraceae are placed in the Caryophyllales near the other carnivorous plant families Nepenthaceae (NE Australia, New Caledonia to S Asia, Madagascar) and Drosophyllaceae (Portugal, Spain, Morocco).

Synonymy: Aldrovandaceae, Dionaeaceae.

Key reference: Marchant et al. (1982).

External resources: accepted names with synonymy & distribution in Australia (APC); author & publication abbreviations (IPNI); mapping (AVH, NVA); nomenclature (APNI, IPNI).

1 DROSERA

Drosera L., Sp. Pl. 1: 218 (1753).

Synonymy: Dismophyla Raf., Fl. Tellur. 3: 36 (1837). Sondera Lehm., Flora 27: 82 (1844).

Carnivorous terrestrial herbs, mostly perennial; stems often reduced. Leaves spiral, often in a basal rosette, bearing glandular hairs that are sometimes irritable; stipules often lobed or absent. Inflorescence a terminal raceme or cyme, flowers sometimes solitary. Flowers 4–5-merous. Calyx and corolla often forming a persistent hood over the mature ovary and capsule. Styles free. Seeds minute, black, elliptical, fusiform or cylindrical.

A genus of about 160 species with a discontinuous distribution in both hemispheres. Australia, with about 120 species, is a major centre of diversity.

1.	Leaves in a basal rosette only; tubers absent	2
1:	Leaves cauline, basal rosette present or absent at flowering time; plant with a vertical rhizome arising from a globose tuber	7
2.	Leaf lamina deeply divided into two or occasionally more linear lobes	1 D. binata
2:	Leaf lamina entire	3
3.	Stipules present, conspicuous, scarious	4
3:	Stipules absent or small and fused to the petiole	5
4.	Flowers solitary, minute, on slender scapes; leaf lamina orbicular	2 D. pygmaea
4:	Flowers few to many on a narrow secund raceme; leaf lamina spathulate	3 D. spatulata
5.	Leaves orbicular, peduncle glandular-pubescent	6 D. glanduligera
5:	Leaves linear-oblong, peduncle glabrous	6
6.	Number of glandular leaves (3–)4–6, 40–70 mm long; non-glandular leaves reduced or absent	4 D. arcturi
6:	Number of glandular leaves 1–2, 60–100(–200) mm long; outer, non-glandular leaves present, spreading	5 D. murfetii
7.	Stem leaves orbicular, peltate, lacking angular lobes; stems trailing, scrambling or climbing	7 D. macrantha
7:	Stem leaves lunar-crescentic, the margins extended as 2 angular lobes; stems erect	8
8.	Sepals glabrous	8 D. auriculata
8:	Sepals hirsute	9
9.	Stems very slender, unbranched, frequently leafless in the upper half; seeds narrow-turbinate, slightly arcuate	9 D. peltata
9:	Stems branched or unbranched, leafy to the inflorescences; basal rosette leaves yellow to green; seeds ovoid to ampulliform or cylindrical	10
10.	Plant up to 10 cm tall with a distinctive yellow-green colour; tubers white; stems often several or if solitary branched from near the base; inflorescences from lower and upper nodes; sepal indumentum sparse, < 0.6 long; petals white, drying white, 4.0–4.5 mm long	10 D. hookeri
10:	Plant (5–)8–22(–30+) cm tall with a pale olive-green to dark red colour; tubers pink or red; stems usually solitary or branched in the upper half; inflorescence from upper nodes only; sepal indumentum dense, > 0.8 mm long, often > 1 mm long; petals white or pink, drying pink, 5–8 mm long	11 D. gunniana

1 Drosera binata Labill. Nov. Holl. Pl. 1: 78, t.105 (1805)

Forked Sundew

Dismophyla binata (Labill.) Raf., Fl. Tellur. 3: 36 (1837).

Illustrations: Harden, Fl. New South Wales 1: 495 (1990); Conn, Fl. Victoria 3: 360, fig. 73g (1996); Cameron, A Guide to Flowers and Plants of Tasmania, 3rd edn, 75, pls 170 & 171 (2000); Corrick & Fuhrer, Wildflowers of Victoria 69, fig. 246 (2000); Woolmore et al., King Island Flora 42 (2002); Whiting et al., Tasmania’s Natural Flora 107 (2004); Simmons et al., A Guide to Flowers and Plants of Tasmania, 4th edn, 99 (2008).

Perennial herb with long spreading fibrous roots; tuber absent; stems reduced. Leaves in a basal rosette, erect; stipules 3–5 mm long, fimbriate, ferrugineous; petioles slender, 2–20 cm long, glabrous; lamina usually once but occasionally up to 3 times divided; lobes linear, usually 4–10 cm long but in depauperate specimens less than 1 cm long. Inflorescences 1–3-branched; branches 10–40 cm long, glabrous; each branch a 15–30-flowered raceme to 50 cm long; bracts linear 1.0–1.5 cm long; pedicels 5–15 mm long. Sepals 5, blackish, 4.0–7.5 mm long, obovate to elliptic, apex acute or laciniate. Petals 5, white, obovate, (1.5–)9–11 mm long. Styles 3, the branches dichotomously divided. Flowering & fruiting Dec.–Mar.

Tas. (all regions except MIS); also WA?, SA, Qld, NSW, Vic., New Zealand. Widespread and found in boggy situations, heath and scrubland, herbfields, from near sea level to over 1000 m alt.

2 Drosera pygmaea DC., Prodr. (DC.) 1: 317 (1824)

Tiny Sundew, Dwarf Sundew

Illustrations: Harden, Fl. New South Wales 1: 495 (1990); Conn, Fl. Victoria 3: 360, fig. 73e (1996); Kirkpatrick, Alpine Tasmania 82, fig. 36e (1997); Woolmore et al., King Island Flora 43 (2002); Gilfedder et al., The Nature of the Midlands 109 (2003); Whiting et al., Tasmania’s Natural Flora 109 (2004).

Herb with fibrous roots; tubers absent; stems absent. Leaves many, in a soil-appressed rosette; stipules 2–3(–5) mm long, scarious, trifid, apices laciniate; petiole flattened, 2.5–6.0 mm long, glabrous; lamina entire, peltate, suborbicular, 1–2.5 mm in diameter. Flowers solitary, axillary; bracts absent; peduncles 1–4, 1–2 cm long. Sepals 4, 1–3 mm long, oblong to elliptic, glabrous, margins entire, apex obtuse. Petals 4, white, 1.5–2.5 mm long, obovate-spathulate, faintly nerved. styles 4, filiform. Seeds black, oblong, c. 0.4 mm long, shining. Flowering & fruiting Sep.–Apr.

Tas. (all regions except MIS); also WA, SA, Qld, NSW, Vic., New Zealand. Widespread and found in sedge and grassland, heathy herbfield, shrubby heath from near sea level to c. 1200 m alt.

3 Drosera spatulata Labill., Nov. Holl. Pl. 1: 79, t.106 (1805)

Rosy Sundew

Drosera spathulata Labill. sensu G.Bentham, Fl Austral. 2: 459 (1864), orth. var.

Illustrations: Harden, Fl. New South Wales 1: 495 (1990); Conn, Fl. Victoria 3: 360, fig. 73d; 628, pl. 9a (1996).

Perennial herb with fibrous roots, a short rootstock; tubers absent; stem reduced. Leaves in a soil-appressed, basal rosette, red, 8–20 mm long; stipules 5–7 mm long, deeply laciniate; lamina ovate-spathulate, narrowing to a broad flat petiole. Inflorescence 1–2(–5?)-branched; branches to 20 cm long; each branch a secund raceme, 5–12-flowered, glandular; bracts short, linear; pedicels 0.3–5.0 mm long. Sepals 5, red, 2–4 mm long, narrow-ovate, minutely glandular. Petals 5, white, c. 1 mm longer than the sepals, obovate to spathulate. Styles 3, each divided to the base into 2 linear lobes, stigmatic at the tip. Capsule c. 1.5 mm long, enveloped in an operculum formed by the withered remains of the corolla. Seeds black, elliptical, c. 0.3 mm long, minutely rugose. Flowering & fruiting mainly Dec.–Mar.

Tas. (BEL, FUR, KIN, TCH, TNS, TSE, TSR, TWE); also Qld, NSW, Vic., Papua New Guinea, New Zealand. Widespread though occasional in boggy peaty soils, wet heath and sedgelands, margins of streams from near sea level to c. 250 m alt.

4 Drosera arcturi Hook., J. Bot. (Hooker) 1: 247 (1834)

Alpine Sundew

Illustrations: Harden, Fl. New South Wales 1: 495 (1990); Conn, Fl. Victoria 3: 360, fig. 73b (1996); Kirkpatrick, Alpine Tasmania 82, fig. 36d (1997); Cameron, A Guide to Flowers and Plants of Tasmania, 3rd edn, 29, pl. 26 (2000); Whiting et al., Tasmania’s Natural Flora 107 (2004); Simmons et al., A Guide to Flowers and Plants of Tasmania, 4th edn, 35 (2008).

Perennial herb with an extensive fibrous root system; tuber absent; stems usually short and mostly underground, shortly clothed in the persistent bases of old leaves. Glabrous lower leaves 1–5, short-lived, absent by anthesis, glandular leaves (3–)4–6(–12), in a basal open irregular rosette; stipules absent; lamina (2–)4–7(–12) cm long, linear to narrow-spathulate, narrowing to a sheathing base. Inflorescence 1–9 cm long, usually longer than the leaves, 1(–2) flowered; bracts small, linear. Sepals black, 3.5–9.0 mm long, elliptic, entire, apex obtuse, shortly connate at the base. Petals 5, white, 3–10 mm long, obovate. Styles 3–4, stout, stigmas pale greenish-white, reniform. Capsule 10–15 mm long, black. Seeds black, lachrimiform, 0.5–1.0 mm long. Flowering & fruiting Dec.– Mar.

Tas. (BEL, TCH, TSE, TSR, TWE); also NSW, Vic., New Zealand. Found mainly at higher elevations in wet heaths and sedgelands, streambanks, in cushion plants, soaks and wet places from near sea level to c. 1200 m alt. Very similar morphologically to D. murfetii, the main differences are the smaller size and higher proportion of glandular to non-glandular leaves of D. arcturi.

5 Drosera murfetii Lowrie & Conran, J. Adelaide Bot. Gard. 27: 17 (2014)

Giant Alpine Sundew

Illustrations: loc. cit.

Perennial herb with fibrous root system; tuber absent; stems reduced, mostly underground, clad in fibrous remnants of old leaves. Glabrous leaves 2–5, persistent, glandular leaves 1–2(–4) in a basal, irregular rosette; stipules absent; lamina 6–10(–20) cm long, linear to lanceolate or narrowly oblong, stem-sheathing at the base. Inflorescence 3–20 cm long, longer than the leaves, 1–2(–5)-flowered; bracts small, linear. Sepals 10–16 mm long, narrowly elliptic, entire, apex obtuse. Petals white, 5–14 mm long, obovate. Styles 4–5, stigmas greenish-white, sometimes slightly to strongly suffused cherry-red, reniform-peltate. Capsule 7–11 mm long. Seeds dark brown, lachrymiform, (0.8–)1–2 mm long. Flowering & fruiting Dec.– Mar.

Tas. (TCH, TSR, TWE), endemic. Found from sea-level to high elevations in wet, peaty soils in heathland, sedgeland and similar habitats to D. arcturi to 1000 m elevation, often forming mixed populations with this species. More common and widespread than D. arcturi at low elevations in the southwest. Morphologically similar to D. arcturi but larger and with fewer glandular leaves. The species can thrive when all leaves are glabrous and there is no possibility of insect trapping.

6 Drosera glanduligera Lehm., Nov. Stirp. Pug. 8: 37 (1844)

Scarlet Sundew, Pimpernel Sundew

Illustrations: Harden, Fl. New South Wales 1: 495 (1990); Conn, Fl. Victoria 3: 360, fig. 73f; 628, pl. 9f (1996); Corrick & Fuhrer, Wildflowers of Victoria 69, fig. 247 (2000).

Annual herb; tubers absent; stems reduced. Leaves in a ± dense ground-appressed rosette, 8–20 mm long; stipules fused to and scarcely wider than the petiole, laciniate, merging with the red multicellular hairs on the petiole; petiole flattened, 5–12 mm long; lamina yellow-green, orbicular, 2.5–7.0 mm in diameter, the clasping hairs with long red tips. Inflorescence 1-several; branches reddish, glandular-hairy, up to 5(–10?) cm tall, each a 2–20 flowered raceme; pedicels 4–8 mm long, deflexed after flowering. Sepals 5, light brown or reddish, 3.0–4.5 mm long, ovate-lanceolate, pilose, the hairs red, septate, gland-tipped, margins fimbriate. Petals 5, bright red, equalling or slightly longer than the sepals, obovate. Capsule finely reticulate. Seeds black, sperical, c. 0.4 mm in diameter, reticulate. Flowering & fruiting Sep.–Nov.

Tas. (FUR); also WA, SA, Qld, NSW, Vic. A poorly collected species found in the north-east and on Flinders Island in heath and sedgelands, open forest and shrubberies, up to 160 m alt.

7 Drosera macrantha Endl. Enum. Pl. 6 (1837)

Climbing Sundew

Drosera planchonii Hook.f. ex Planch., Ann. Sci. Nat. (Paris) ser. 3, 9: 248 (1848); D. menziesii R.Br. var. albiflora Benth., Fl. Austral. 2: 468 (1864); D. macrantha Endl. subsp. planchonii (Hook.f. ex Planch.) N.G.Marchant, Fl. Australia 8: 383 (1982).

Illustrations: Marchant et al., Fl. Australia 8: 37, fig. 9 (1982); Conn, Fl. Victoria 3: 360, fig. 73a; 628, pl. 9b (1996); Cameron, A Guide to Flowers and Plants of Tasmania, 3rd edn, 63, pl. 142 (2000); Corrick & Fuhrer, Wildflowers of Victoria 69, fig. 248 (2000); Whiting et al., Tasmania’s Natural Flora 108 (2004); Simmons et al., A Guide to Flowers and Plants of Tasmania, 4th edn, 81 (2008).

Perennial herb with an erect rhizome arising from a globular tuber; tuber ± globose; stems 30–60 cm long, simple, slender, leafy, trailing, scrambling or climbing. Leaves: stipules absent; lower leaves few, reduced and scale-like, alternate; upper leaves paired or in false whorls of 3 or 4; petioles (5–)10–50 mm long; lamina orbicular-peltate, 3–7 mm in diameter, deeply concave, inverted. Inflorescence a terminal raceme or panicle 2-several-flowered; pedicels 3–15 mm long. Sepals 5, blackish, 3–8 mm long, broad-elliptical or ovate, pilose, the hairs appressed, septate, glandular, margins ciliate below, laciniate at the apex. Petals 5, white or pale pink, 6–10 mm long, obovate. Styles 3, divided from the base into numerous filiform dichotomous segments. Flowering & fruiting Aug.–Dec.

Tas. (FUR, KIN, TNM, TSE); also WA, SA, Vic. Widespread, though occasional, and found in coastal and estuarine situations, up to 90 m alt., in open heathy woodland and sedgelands. For discussion on the variation found in the species see Conn (1984) and Marchant and Lowrie (1992).

8 Drosera auriculata Backh. ex Planch., Ann. Sci. Nat. (Paris) ser. 3, 9: 295 (1848)

Tall Sundew

Drosera peltata subsp. auriculata (Backh. ex Planch.) B.J.Conn, J. Adelaide Bot. Gard. 3: 98 (1981).

Illustration (often as D. peltata subsp. auriculata): Curtis & Morris, The Student’s Flora of Tasmania 1, rev. edn: 188, fig. 46 (1975); Harden, Fl. New South Wales 1: 494 (1990); Conn, Fl. Victoria 3: 628, pl. 9a (1996); Cameron, A Guide to Flowers and Plants of Tasmania, 3rd edn, 61, pls 135 & 136 (2000); Corrick & Fuhrer, Wildflowers of Victoria 69, fig. 249 (2000); Harris et al., One Hundred Islands: the Flora of the Outer Furneaux 118 (2001); Woolmore et al., King Island Flora 43 (2002); Gilfedder et al., The Nature of the Midlands 109 (2003); Simmons et al., A Guide to Flowers and Plants of Tasmania, 4th edn, 81 (2008).

Perennial herb with an erect rhizome arising from a globose tuber, roots produced in the axils of scales on the rhizome. Rosette leaves (often absent by flowering time) appressed to the soil, petiole 3–15 mm long, lamina flattened semi-orbicular, lunate, not peltate, 2–6 mm in diameter; lower stem leaves solitary, often reduced to a petiole with a minute unexpanded lamina; upper stem leaves solitary or in groups of 2–6, lamina crescentic, auriculate, peltate, 2–4 mm in diameter. Inflorescence erect, solitary, branching above, or rarely with a single branch from the base, 6–65 cm tall, each branch a terminal raceme, 2–8-flowered; bracts narrow-lanceolate to narrow-ovate, c. 1 mm long; pedicels 4–14 mm long. Sepals blackish, 3–5 mm long, broad-lanceolate to ovate, glabrous, apex laciniate. Petals usually pink, 5–8 mm long, obovate. Styles 3, digitately divided above. Seeds black, 0.5–0.6 mm long, narrowly cylindric to oblong-cylindric, with a persistent funicle and the testa prolonged into a flat apical extension, reticulate. Flowering & fruiting Aug.–Mar.

Tas. (all regions except MIS); also SA, Qld, NSW, Vic., New Zealand. Widespread in a variety of habitats from near sea level to 850 m alt. Found in light forest, coastal shrubberies, heath and sedgelands, coastal dunes, margins of streams in rain forest.

9 Drosera peltata Thunb., Dissertatio Botanica de Drosera 7 (1797)

Red Sundew

Drosera gracilis Planch., Ann. Sci. Nat. (Paris) ser. 3, 9: 297 (1848); Drosera peltata var. gracilis (Planch.) Benth., Fl. Austral. 2: 465 (1864).

Erect perennial herb, rhizome erect, arising from a globose tuber. Leaves, stems and tubers red. Rosette leaves normally red, soil-appressed, petiole 4.5–8.0 mm long, flattened, lamina 3–5 mm in diameter, semi-orbicular-lunate, not peltate; cauline leaves solitary or in groups of 3 or 4, crescentic, auriculate, peltate, petiole 7–8 mm long, lamina 3–6 mm in diameter. Inflorescence slender, solitary, unbranched, frequently leafless in the upper half, scape ending in a terminal raceme, 2–5-flowered; bracts c. 1.5 mm long, fimbriate. Sepals dark olive green, turning black, 2.5–3.5 mm long, narrow elliptical, hirsute. Petals white, 3.5–4.5 mm long, obovate. Seeds 0.4–0.5 mm long, narrow-turbinate, slightly arcuate, apex with a short flattened extension. Flowering & fruiting Nov.–Feb.

Tas. (BEL, FUR, KIN?, TCH, TSE, TSR, TWE), VIC, NSW. Found in marshes, peaty heath, margins of rivers and streams from near sea level to 1050 m altitude. This taxon has a confusing nomenclature history and has been considered by many authors to be synonymous with D. hookeri and D. gunniana. For a full discussion of the nomenclature, refer to de Salas (2018). The application of the name D. peltata has changed after the Gibson et al. revision of 2012, who determined that the holotype of D. peltata was conspecific with that of D. gracilis.

10 Drosera hookeri R.P.Gibson, B.J.Conn & Conran, J. Adelaide Bot. Gard. 24: 41 (2010)

Drosera foliosa Hook.f. ex Planch. Ann. Sci. Nat. (Paris) ser. 3, 9: 298 (1848); Drosera peltata var. foliosa (Planch.) Benth., Fl. Austral. 2: 465 (1864).

Yellowish green leafy perennial often forming ± dense swards; rhizome erect, arising from a white globose tuber. Basal leaves yellow-green, soil-appressed, petiole flattened, 5–14 mm long, lamina 7–11 mm wide, semi-orbicular, lunate, not peltate; cauline leaves yellow-green, with petiole 5–11 mm long, lamina 3–6 mm in diameter, crescentic, auriculate or occasionally the auriculate lobes absent. Inflorescence 1–several branched, 1–10 cm tall, branched from the base and appearing multi-stemmed, each branch terminating in short racemes from lower and upper nodes; bracts linear-lanceolate, fimbriate, c. 2.5 mm long, pedicels 5–8 mm long. Sepals green or blackish, 2.5–3.0 mm long, silky-pubescent, margins fimbriate. Petals white, 4.0–4.5 mm long, obovate, drying cream or white. Seeds black, cylindrical witha short neck, 0.6–0.7 mm long, 0.25 mm wide, surface reticulated. Flowering & fruiting Sep.–Dec.

Tas. (FUR, TNM, TSE); also Vic, SA. Found in the midlands and the north-east of the island of Tasmania in grasslands, herbfields with a grassy understorey, oped woodland and pasture, from sea level to 300 m altitude. There has been considerable confusion regarding the nomenclature and taxonomy of this group of species (see comment under D. peltata).

11 Drosera gunniana (Planch.) de Salas, Muelleria 36, 102 (2018)

Pale Sundew

Drosera peltata var. gunniana Planch., Ann. Sci. Nat. (Paris) ser. 3, 9: 297 (1848).

Illustrations: Marchant et al., Fl. Australia 8: 23, fig. 6 (1982); Harden, Fl. New South Wales 1: 494 (1990); Conn, Fl. Victoria 3: 360, fig. 73c; 628, pl. 9d (1996), as D. peltata var. peltata.

Erect perennial herb with an erect rhizome arising from a pink or red globose tuber. Rosette leaves soil-appressed, olive-green often suffused orange, usually present at flowering time, petiole flattened 3–14 mm long, lamina 5–10 mm in diameter, semi-orbicular-lunate, not peltate; lower cauline leaves sometimes reduced to a petiole with a minute unexpanded lamina; upper leaves yellow-green or reddish, solitary or in groups of 2–4, petiole 7–10 mm long, lamina crescentic, auriculate, peltate, 5–6 mm in diameter. Inflorescence unbranched, subtended by several vegetative internodes, (5–)8–22(–30+) mm tall, yellow-green or reddish, branching from the top-most 1 or 2 vegetative internodes, or unbranched, flowers in axillary and terminal racemes; bracts lanceolate, fimbriate, hairy, margins fimbriate. Sepals olive green, rarely dark red, turning blackish, 3–5 mm long, hirsute, margins fimbriate. Petals pink or white, 5–8 mm long, obovate. Seeds black, cylindrical with a short neck, 0.5 mm long, c. 0.25 mm wide, surfece reticulated. Flowering & fruiting Oct.–Dec.

Tas. (FUR, TCH, TNM, TSE, TSR); also SA, NSW, Vic. Found in heath and sedgeland, open forest, margins of sand dunes, among mosses in skeletal soils, from near sea level to 250 m alt. Most Australian authors have included this taxon in synonymy with D. peltata and D. hookeri, but in Tasmania these taxa exhibit sufficient differences to warrant recognition as separate species. Gibson et al. treated D. hookeri broadly, including the concept of D. gunniana in synonymy. However, in Tasmania these two taxa are easily distinguished, and occupy different environmental niches. Furthermore, both taxa grow sympatrically at many localities and flower simultaneously, remaining distinct and not hybridising.

References