An illustrated and annotated key to the Tasmanian species of Senecio (Asteraceae)

Mark Wapstra, Ian Thompson and Alex Buchanan

Wapstra M., Thompson I.R., Buchanan A.M. 2008. An illustrated and annotated key to the Tasmanian species of Senecio (Asteraceae). Kanunnah 3: 49–93. ISSN 1832-536X. A key to the Tasmanian species of Senecio (Asteraceae) is presented, including all native and naturalised species, subspecies and varieties (41 taxa in total). Two species formerly placed in Senecio, Delairea odorata Lem. and Brachyglottis brunonis (Hook.f.) B.Nord., are also included. An illustrated glossary of terms is provided, together with comments on the identification and discrimination of taxa and distribution maps.

Mark Wapstra, Environmental Consulting Options Tasmania 28 Suncrest Avenue, Lenah Valley, Tasmania, 7008, Australia. Email: [email protected] Ian Thompson, School of Botany, The University of Melbourne Parkville, Victoria, 3010, Australia. Email: [email protected] Alex Buchanan, Tasmanian Herbarium GPO Box 252-04, Hobart, Tasmania, 7001, Australia. Email: [email protected]

Key Words: Senecio, groundsel, fireweed, Asteraceae, key, Tasmania.

Senecio is a large cosmopolitan genus com­ centropappus F.Muell. for which the name prising about 1250 species (Bremer 1994). Brachyglottis brunonis (Hook.f.) B.Nord. is Australia has 87 native species (Thompson current. Curtis (1963) did not recognise any 2006) and ten naturalised species, the varieties or subspecies in Senecio. latter mostly from South Africa and some Buchanan (2005) in the Census of Vas­ from Europe. Curtis (1963) in Part 2 of the cular Plants to Tasmania updated the list Student’s Flora of Tasmania recognised 22 of species of Senecio present in Tasmania, species in Senecio, four being naturalised mainly from the recent taxonomic work and eighteen native. Two have since been of Thompson (2004a–d, 2005). Excluding transferred to other genera, these being the hybrid taxa (only S. Xorarius J.M.Black introduced S. mikanioides Otto ex Harv., is currently recognised in Buchanan now known as Delairea odorata Lem., and S. (2005) but is herein not considered

49 KANUNNAH Mark Wapstra, Ian Thompson and Alex Buchanan

worthy of taxonomic recognition) and S. or varieties often requires microscopic pectinatus var. major F.Muell. ex Belcher examination of capitula, stems or leaves. (now recognised by Thompson (2006) However, an annotated and illustrated as a mainland endemic), S. linearifolius glossary is provided following the key var. latifolius (that is herein recognised as to explain technical terms. Each species present) and S. georgianus (hitherto not has some accompanying notes on its recognised by Buchanan (2005)), 41 taxa recognition (in particular, confusing of Senecio are now recognised in Tasmania species or characters), distribution and (Buchanan 2005). Of the 29 native species, habitat (also following the key). one is represented by two subspecies, one Fresh or dried material may be used by one subspecies, two by one variety, one in the key below. Working with fresh by four varieties and one by five varieties. material, especially flowering material, Seven taxa are endemic to Tasmania. The is often much easier. Decisions at each four naturalised species are S. angulatus, couplet should be made after considering S. elegans, S. jacobaea and S. vulgaris. All as many of the characters mentioned as Tasmanian species, except Senecio angulatus possible. As with most complex keys, which is a climber, are herbaceous and familiarity breeds confidence. It is recom­ may be woody basally. mended that users of the key try to The almost doubling of the number identify taxa familiar to them to get used of Tasmanian Senecio taxa since Curtis to the terminology. (1963) has prompted the construction of the following key. It is mainly intended What material needs to assist field workers to identify this to be collected complex suite of species without needing Some taxa of Senecio require very little to delve into more complex taxonomic material to identify them with confidence papers. However, for recent descriptions of (e.g. some subalpine radiate species Tasmanian species, the reader is referred can be identified from basal rosettes to Thompson (2004a–d, 2005, 2006). With of leaves with no flowering material), three species listed as threatened on the although many require carefully collected Tasmanian Threatened Species Protection Act specimens that include the root system, 1995, and several others known from very representative parts of the stem, leaves few records (including several that qualify from different parts of the stem and a as ‘presumed extinct’ because they have range of flower ages (e.g. most of the non- not been recorded for more than 50 years), radiate species, i.e. the disciform species). it is important that field workers can Several specimens collected from a site can correctly identify species of Senecio. make identification easier as the presence of characteristics such as coarse hairs on Some notes on using the key stems and leaves, cobwebby hairs on As with most keys, it is difficult to avoid flowerheads and hairs on achenes can the use of technical terms, especially in vary depending on the age of plants so it the case of a genus like Senecio, in which is often desirable to develop a ‘population the identification of species, subspecies picture’, rather than rely on identification

50 An Illustrated and Annotated Key to the Tasmanian Species of Senecio KANUNNAH from a single specimen. With the disciform Hybrids between disciform and radiate species, it is particularly important to species are usually identifiable by the collect mature achenes because young presence of ligules that are shorter (mostly achenes will be considerably shorter and 0.5–4 mm long), and narrower than those less hairy than their mature counterparts. seen in radiate species, and, in the field, by Collected material should be pressed the identification of populations of parent promptly, especially for taxa with larger species in the vicinity. leaves prone to curling, and for those Several hybrids between radiate and with large radiate flowerheads that wither disciform species have been recognised quickly. If prompt curation is not possible, as occurring in Tasmania. One is a hybrid notes should be made on the length and between S. pinnatifolius and S. biserratus. number of ray florets in radiate species This entity was described as S. Xorarius as this is easier to do with fresh material. (Black 1928). It occurs infrequently on the Specimens will stay fresh if carefully Victorian and South Australian coasts, wrapped in moist (but not wet) paper towel and only one Tasmanian specimen at (or moss) and kept cool for transport. Some the Tasmanian Herbarium has been fleshy leaved species will require careful determined as this entity. It does not curation to avoid development of mould. appear to form stable populations and Light pressing is recommended for all taxa plants are sterile (Lawrence 1980); thus to avoid overly deforming flowerheads (or is not considered worthy of taxonomic measuring the diameter of the flowerheads recognition. The other recognised hybrid upon collection is advised). If far enough is between S. linearifolius var. linearifolius advanced at the time of collection, achenes and S. minimus. There are a few collections may develop to maturity during pressing. of this hybrid from both Tasmania and Victoria. Hybrids between S. linearifolius Species nomenclature (unknown variety but probably var. Botanical nomenclature follows Buchanan linearifolius) and S. hispidulus have also been (2005), except where indicated in the observed recently (M. Wapstra, pers. obs.) species’ notes, and vernacular nomen­ in the north-east (Elephant Pass) and the clature follows Wapstra et al. (2005). An south-east (Surges Bay). asterisk (*) next to the botanical name in Hybrids between disciform species may the key and notes indicates that the species key with difficulty to a recognised taxon is naturalised in Tasmania. and users of the key should be cautious if a hybrid is suspected – collection of A note on hybrids additional possible parent material from Species of Senecio readily hybridise, both the vicinity may be necessary to help within and between the two morph­ confirm identification of such entities. ologically distinct groups (i.e. the radiate Hybridisation between non-radiate parents and disciform species). Hybrids are not has been recorded from mainland Aust­ralia inc­luded in the present key but are discussed and is a possibility in Tasmania wherever in the notes below each species in the species co-occur (up to five species of key that may be possible parent species. Senecio can co-occur together).

51 KANUNNAH Mark Wapstra, Ian Thompson and Alex Buchanan

(generally difficult to access), many parts of the central, eastern and northern Midlands (mainly private property), parts of the north-east and several areas in the north- west (notably much of the private property areas and two offshore islands). This map also shows that many areas of the state are represented by numerous collections. Of note are the coastal areas, many of the Bass Strait islands, parts of the Central Highlands and around the major population centres in the Tamar (Launceston) and Derwent (Hobart) river systems. Macquarie Island, a sub-antarctic island administered by Tasmania, is not included on the distrib­ ution maps because no species of Senecio Fig. 1. Distribution records for all Tasmanian are known from there (Buchanan 2005). species of Senecio. Conservation status Distribution maps Three species are presently listed as Maps are based on specimens held by threatened on the Tasmanian Threatened the Tasmanian Herbarium (excluding Species Protection Act 1995 (S. macrocarpus as unidentified specimens), specimens from extinct, and S. squarrosus and S. velleioides Mark Wapstra’s personal herbarium, and as rare). Several other species, most notably records of threatened taxa held by the S. campylocarpus, S. extensus, S. georgianus, Threatened Species Section of the Depart­ S. hispidissimus, S. longipilus, S. microbasis, S. ment of Primary Industries and Water. It phelleus, S. psilocarpus, S. tasmanicus and S. should be noted that not all the records vagus) are represented by limited and/or early from the latter source are supported by collections. It may be premature, however, confirmed herbarium specimens. Distrib­ to consider these species as either extinct (in ution maps and notes are provided as a the case of species not recorded for many guide only and should not be used as a decades) or threatened (in the case of species reliable method of identification. Several represented by only a few collections). The species, for example, are currently known recent rediscovery of S. campylocarpus from only from the Bass Strait islands or from the heart of Campbell Town and recent scant records from one part of the state, but collections of S. phelleus from a popular such species may be more widespread. walking track just south of Hobart attest All records for Tasmanian Senecio are to the need for more collecting. Through shown in Fig. 1. This map clearly demon­ increased familiarity with Tasmanian strates that several parts of the state are species of Senecio, it is likely that further represented by very few or no collections: collections will be made of species that are in particular, several parts of the south-west currently poorly represented in herbaria.

52 An Illustrated and Annotated Key to the Tasmanian Species of Senecio KANUNNAH

Key to the Tasmanian species of Senecio (and some allied taxa)

1a Plants glabrous, scrambling, twining 6b Involucre 4–15 mm long, > 2 mm dia­ or climbing; leaves distinctly petiolate meter; disc florets > 30; ray florets c. and with a lobate lamina 1–2 times as 13, or more; leaves sometimes lobate long as broad — 2 or pinnatisect — 10 1b Plants glabrous or hairy, not growing 7a All leaves appearing entire — as above; leaves various, not entirely S. linearifolius var. linearifolius as above — 3 7b At least the stem leaves callus-dent­ 2a Capitula radiate; leaves dark green, iculate, denticulate or dentate — 8 with lamina generally longer than 8a New axillary growth densely cob­ broad and with base truncate to webby to woolly; involucre mostly > cuneate; petiole 1–4 cm long; stipules 4.0 mm long — S. linearifolius var. absent — S. angulatus* arachnoideus 2b Capitula discoid; leaves pale green, 8b New axillary growth glabrous or lamina about as broad as long and only sparsely cobwebby; involucre with base strongly cordate (heart- 2.5–4.0 mm long — 9 shaped); petiole 4–7 cm long; 9a Mid- to upper-stem leaves less than kidney-shaped stipules present — 25 mm wide and with length:width Delairea odorata* ratio > 4; leaf-base attenuate to cuneate 3a Capitula radiate — 4 — S. linearifolius var. denticulatus 3b Capitula not radiate — 23 9b Mid- to upper-stem leaves more than 4a Woody shrubs or trees, 2–4 m high; 25 mm wide, or if narrower then leaves linear, with margins entire, viscid length:width ratio < 4 and/or with leaf- (Mts Wellington and Dromedary) — base broad-cuneate, truncate or cordate Brachyglottis brunonis (heart-shaped) — S. linearifolius var. 4b Herbaceous plants (sometimes woody latifolius basally), to 2 m high; leaves various, 10a Leaves bi- or tri-pinnatisect, with not viscid (distribution various) — 5 ultimate segments variable in width; 5a Ligules of ray florets crimson to calycular bracteoles narrow-lance­ purple, or rarely white (and if white, olate, to c. 0.5 mm wide; achenes of then inflorescences of several capitula) ray florets glabrous but those of disc — S. elegans* florets hairy — S. jacobaea* 5b Ligules of ray florets yellow, or if ever 10b Leaves not bi- or tri-pinnatisect, cream or whitish then inflorescences or if so with all ultimate segments of a single capitulum — 6 of leaves similarly narrow and 6a Involucre < 5.5 mm long, < 2 mm with calycular bracteoles ovate to diameter; disc florets < 30; ray florets lanceolate, 0.7–1.6 mm wide; achenes 4–8; leaves never lobate or pinnatisect either all hairy or all glabrous — 11 — 7 (S. linearifolius)

53 KANUNNAH Mark Wapstra, Ian Thompson and Alex Buchanan

11a Plants rosette-forming; leaves/bracts mostly of 3 or more capitula; ligules above mid-stem much smaller than yellow — S. leptocarpus basal leaves; calycular bracteoles 15b Leaves 1–4 mm wide, with teeth 1 or narrow-oblong, > 4 mm long (mostly 2 per side; inflorescences of a single montane to alpine) — 12 capitulum; ligules white or cream — 11b Plants not rosette-forming, or if so S. albogilvus then calycular bracteoles ovate, <_ 3 16a Leaves entire or denticulate to mm long; largest leaves occurring dentate, strongly amplexicaul; caly­ along stems (mostly lowland) — 16 cular bracteoles up to 4; plants often 12a Leaves distinctly hairy; stem leaves/ glaucous — S. velleioides bracts up to 5 (excluding distal-most 16b Leaves variously dissected, not 1 cm of stem) — 13 or hardly amplexicaul; calycular 12b Leaves glabrous or nearly so; stem bracteoles 6 or more; plants not leaves/bracts 5–15 (excluding distal- glaucous — 17 most 1 cm of stem) — 14 17a Calycular bracteoles 5–10 mm long; 13a Basal leaves not spathulate (demar­ phyllaries with conspicuous dark hairs; cation between petiole and blade more ligules 7- or 8-veined — S. vagus or less abr upt), usual ly at least some > 15 subsp. vagus mm wide; upper surface lacking broad- 17b Calycular bracteoles 1–3 mm long; based coarse hairs; inflorescences of phyllaries glabrous; ligules mostly 1–4 capitula — S. primulifolius 4-veined — 18 13b Basal leaves spathulate, < 15 mm 18a Leaves bi- or tri-pinnatisect; stems wide; upper surface with broad-based succulent; capitula and leaves rather coarse septate hairs to c. 1.5 mm crowded (Bass Strait islands) — long (or their stout residual bases); S. pinnatifolius var. capillifolius inflorescences of a single capitulum 18b Leaves not bi-pinnatisect, or if so — S. papillosus then stems not or hardly succulent; 14a Leaves deeply lobate to pinnatisect, capitula and leaves crowded or lax with 3–6 more or less oblong segments (widespread) — 19 per side, concolorous or nearly so; 19a Stereome of inner phyllaries more inflorescences of 1 capitulum (rarely than twice as broad as stereome of 2); ligules yellow — S. pectinatus var. outer phyllaries measured c. 1 mm pectinatus below apex, and usually bordered by 14b Leaves less dissected than above, with a purple chevron; margins of outer 1–several serrations or somewhat phyllaries c. as broad as the stereome triangular lobes per side, markedly 1 mm below apex — S. pinnatifolius discolorous; inflorescences of 1 or var. lanceolatus more capitula; ligules yellow, white, 19b Stereome of inner phyllaries less than or cream — 15 twice as broad as that of outer phyllaries 15a Leaves 4–10 mm wide, with teeth or measured c. 1 mm below apex, usually lobes 3 or more per side; inflorescences not bordered by a purple chevron but

54 An Illustrated and Annotated Key to the Tasmanian Species of Senecio KANUNNAH

sometimes weakly so; margin of outer 24a Capitula discoid, with florets 10–16; phyllaries narrower than stereome corolla of all florets 5-lobed and 1 mm below apex — 20 markedly dilated distally; plant 20a Leaves halfway to 2/3 along stems/ aromatic, usually quite glaucous — major branches broadest beyond mid­ S. odoratus leaf and/or with marginal points or 24b Capitula disciform with florets mostly segments clearly more numerous in more than 16; corolla of outer florets distal half of leaf; peduncles commonly hardly dilated distally and less than hairy at flowering (montane to alpine) 5-lobed; plants not usually aromatic, — S. pinnatifolius var. alpinus not glaucous — 25 20b Leaves halfway to 2/3 along stems/ 25a Plants greyish in appearance with a major branches not broadest beyond cottony to woolly indumentum of midleaf and with marginal points or fine hairs at least on stems and lower segments not more numerous in distal surface of leaves; coarse hairs absent half; peduncles commonly glabrous — S. quadridentatus at flowering (generally lower than 25b Plants not greyish in appearance montane) — 21 with fine hairs rather sparse except 21a Leaves generally only slightly fleshy on newest growth; if ever somewhat (although succulent on coast); base of greyish overall then the indumentum upper-branch leaves (excluding any of coarse hairs — 26 lobes or segments) generally not broader 26a Achenes lageniform, > 2.8 mm long, than the branch (east coast and inland) with hairs rather sparse in lines; — S. pinnatifolius var. pinnatifolius secondary roots slightly tuberiform; 21b Leaves fleshy; base of upper-branch — S. prenanthoides leaves commonly broader than branch 26b Achenes not lageniform and/or (west coast) — 22 < 2.8 mm long, with hairs variously 22a Achenes 3.0–5.5 mm long; pappus dense; secondary roots not tuberiform persistent; broadest stereomes of — 27 phyllaries well over 1 mm wide 27a At least lower- to mid-stem leaves (sandy sites only) — S. spathulatus lobed; marginal teeth scattered (< 3 var. spathulatus per cm) — 28 22b Achenes < 3.0 mm long; pappus not 27b Stem leaves not lobed; margins often persistent; broadest stereomes of crowded-toothed (c. 5 per cm) — 29 phyllaries to c. 1 mm wide (rocky sites 28a Lobation of leaves markedly angled as well as on sand) — S. pinnatifolius forwards, with acute teeth on the var. maritimus lobes also angled forwards; upper 23a Involucres all or mostly of 7–10 surface of upper-stem leaves nearly phyllaries — 24 glabrous; achenes (2.0–)2.5–3.2 mm 23b Involucres all or mostly of more long — S. biserratus than 11 phyllaries (mostly c. 13, but sometimes more) — 30

55 KANUNNAH Mark Wapstra, Ian Thompson and Alex Buchanan

28b Lobation of leaves nearly at right- iform (neck c. 0.2 mm long); achene angles to midrib, with subacute hairs forming bands c. as wide as ribs teeth on the lobes hardly angled — 36 forwards; upper surface of all leaves 33a Involucre 6.0–9.0 mm long; achenes with scattered coarse hairs; achenes lageniform, 2.8–4.5 mm long; sec­ 1.5–2.2 mm long; achenes red-brown . ond­ary roots slightly tuberiform — — S. hispidulus S. prenanthoides 29a Leaf margins smooth or with scattered 33b Involucre 3.0–6.0 mm long; achenes points; inflorescences of few to c. 30 obloid, 1.0–2.2 mm long; secondary capitula — S. microbasis roots not tuberiform — 34 29b Leaf margins with numerous crowded 34a Peduncle and capitulum glabrous at denticulations; inflor­es­cences of 100s flowering; calycular bracteoles 4–8 — of capitula — S. minimus S. hispidulus 30a Capitula discoid; calycular bracteoles 34b Peduncle and capitulum (in region of conspicuously jet black in distal 0.5–1 bracteoles) cobwebby to woolly at mm; near glabrous annuals to 0.5 m flowering; calycular bracteoles 6–12 high — S. vulgaris* — 35 S. glomeratus 30b Capitula disciform, or if discoid 35a Achenes < 1/3 of phyllary length then plants densely hairy; calycular (phyllaries 4.0–6.0 mm long; achenes bracteoles with black pigmentation 1.0–1.7 mm long); ped­uncles and absent or inconspicuous and confined lower parts of capitulum moderately to very tip; short-lived perennials of cobwebby to woolly; pappus usually various height, hairy or not — 31 > 5 mm long — S. glomeratus subsp. 31a At least lower-stem region developing glomeratus coarse hairs (these sometimes 35b Achenes > 1/3 of phyllary length partly obscured by overlying wispy (phyllaries 3.0–5.0 mm long; achenes extensions), these hairs sometimes 1.3–2.2 mm long); peduncles and becoming lost with age — 32 lower parts of capitulum sparsely 31b Stems glabrous or with all hairs to moderately cobwebby; pappus very fine (appressed-cottony or usually < 5 mm long — S. glomeratus woolly), nowhere developing any subsp. longifructus coarse hairs — 38 36a Upper-stem leaves not or hardly 32a Involucre < 2.0 mm diameter (see auriculate; apex of phyllaries black- glossary), 3.0–6.0 mm long or to 9 tipped but without a zone of purple mm long but then achenes markedly below this; achenes commonly lageniform (neck 0.3–1.0 mm long); slightly lageniform — S. longipilus achene hairs forming lines or bands 36b Upper-stem leaves usually auriculate; narrower than ribs — 33 apex of phyllaries black-tipped or 32b Involucre mostly > 2.0 mm in not, commonly with a zone of purple diameter, (5.0–)6.0–12.0 mm long; immediately below; achenes narrow- achenes not or only slightly lagen­ obloid — 37

56 An Illustrated and Annotated Key to the Tasmanian Species of Senecio KANUNNAH

37a Coarse hairs on stems persisting flowering lower-stem region glabrous throughout; achenes light to mid or sparsely cottony and capitula and brown; phyllaries c. 13 — S. peduncles cobwebby; outer achenes hispidissimus dark brown — S. campylocarpus 37b Coarse hairs on stems giving way 43a Calycular bracteoles 1.0–2.0 mm to cottony hairs above mid-stem; long, 3–5 per capitulum; capitulum achenes sometimes dark-brown to glabrous at flowering — 44 blackish; phyllaries c. 13, or often 43b Calycular bracteoles 2.0–5.0 mm long, 16–20 — S. squarrosus more than 5 per capitulum or if 3–5 38a Capitula discoid — S. georgianus then capitula (in region of bracteoles) 38b Capitula disciform — 39 cobwebby at flowering — 45 39a Achenes lageniform, 2.0–7.0 mm 44a Involucre 1.0–1.5 mm diameter; florets long — 40 up to 25; mature receptacle 1.0–2.0 39b Achenes obloid to ellipsoid, 1.5–3.0 mm diameter — S. microbasis mm long — 43 44b Involucre 1.5–2.0 mm diameter; florets 40a Involucre > 3.0 mm diameter; caly­ more than 25; mature receptacle cular bracteoles > 3.0 mm long; 2.5–3.0 mm diameter — S. phelleus achenes with hairs in bands c. as 45a Peduncles and capitula glabrous broad as ribs — S. macrocarpus at flowering (swamp plants) — 40b Involucre < 3.0 mm diameter; S. psilocarpus calycular bracteoles < 3.0 mm long, 45b Peduncles and capitula (in region of appressed; achenes with hairs in lines bracteoles) cobwebby at flowering or bands much narrower than ribs 41 (not swamp plants) — 46 41a Leaves in lower third of stems with 46a Achenes with dense hair-bands c. as scattered coarse hairs; achenes 5–7 broad as ribs, mid-brown or blackish mm long, markedly lageniform with between bands; involucre 2.0–4.0 mm a very long slender neck (> 1 mm diameter (lowland) — S. squarrosus long) — S. tasmanicus 46b Achenes glabrous or hairs in lines 41b Leaves in lower third of stems much narrower than ribs, olive- lacking coarse hairs; achenes 2.0–4.5 brown or red-brown; involucre mm long, with neck shorter (< 1 mm 1.7–2.0 mm diameter (montane or long) — 42 higher altitudes) — 47 42a Plants with a grey appearance; taproot 47a Achenes 2.5–4.0 mm long, olive- stout; at start of flowering lower-stem brown; calycular bracteoles extending region densely cottony to woolly and up to c. one-quarter of way along capitula and peduncles either glabrous involucre; upper-stem leaves entire or or cobwebby; outer achenes usually denticulate — S. gunnii red — S. quadridentatus 47b Achenes 2.0–2.2 mm long, red-brown; 42b Plants with a greenish appearance; calycular bracteoles extending c. one taproot inconspicuous; at start of third to halfway along involucre; upper- stem leaves lobate — S. extensus

57 KANUNNAH Mark Wapstra, Ian Thompson and Alex Buchanan

Notes on Tasmanian distinctive feature and makes confusion species of Senecio with other species unlikely. Belcher (1996) notes that the recognition of this species Senecio albogilvus I.Thomps., in dried material is easy because of the Muelleria 20: 130 (2004) distinctive leaves and bracts, even though ‘white alpine groundsel’ the rays usually undergo discoloration (Fig. 2) during drying and are not then reliably This is one of the subalpine species en­ different in colour from dried material of demic to Tasmania. It was formerly S. pectinatus. known as S. pectinatus var. ochroleucus but An old specimen collected by a Dr Thompson (2004c) raised it to specific Mil­ligan from Tasmania (MEL667723) rank. It is widespread in central-western has leaves similar to S. albogilvus but an and southern Tasmania (including Mt inflorescence of six capitula. It is unclear Wellington) at higher altitudes, where what the original colour of the ligules was it grows in rocky sites in herbfields, in this specimen. This may be an aberrant heathlands and shrublands. plant or possibly a hybrid between S. This species is distinct from S. pectinatus albogilvus and S. leptocarpus. on the basis of leaf morphology, and is perhaps more similar to S. leptocarpus *Senecio angulatus L.f., Suppl. 369 (both have similarly toothed or lobed, (1782) ‘scrambling groundsel’ discolorous leaves but those of S. albogilvus (Fig. 3) are considerable smaller). The white-cream This is a vigorous, fleshy leaved climber colour of the ligules is perhaps the most that is becoming very common in parts of

Fig. 2. Distribution of Senecio albogilvus. Fig. 3. Distribution of Senecio angulatus.

58 An Illustrated and Annotated Key to the Tasmanian Species of Senecio KANUNNAH the state’s south-east and east (e.g. Tasman The species is widespread and common Highway north of Swansea, township of in Tasmania, especially along coasts (inc­ Swansea, a few sites around Hobart) and luding islands) and major coastal river scattered localities elsewhere (e.g. Strahan, systems; there are, however, also several upper Derwent Valley, Eddystone Point). It inland records. Senecio pinnatifolius var. is a native of South Africa. lanceolatus and S. biserratus occasionally hybridise. This hybrid entity was described Senecio biserratus Belcher, Ann. as S. Xorarius but is not considered worthy Miss. Bot. Gard. 43: 43 (1956) of taxonomic recognition. See notes ‘jagged fireweed’ under S. pinnatifolius var. lanceolatus for (Fig. 4) further discussion. This is a distinctive species that grows to 1 m. It resembles S. minimus but differs Senecio campylocarpus I.Thomps., most obviously by the degree of dis­section Muelleria 20: 139 (2004) and shape of the leaf segments. In Tas­ ‘bulging fireweed’ mania, prior to the major revision of Senecio, (Fig. 5) many jagged-leaved specimens (including In Tasmania, the species is known from many ‘inland’ records) of Senecio are likely three collections: one from ‘near Laun­ to have been attributed to this species. It was ceston’ in 1888, another from a ‘swamp possibly previously confused with other near Cressy’ in 1943, and most recently jagged-leaved taxa such as S. glomeratus, from the banks of the Elizabeth River, S. hispidulus and the more recently des­ Campbell Town, in 2006. This species cribed S. hispidissimus. usually occurs in lowland forest and

Fig. 4. Distribution of Senecio biserratus. Fig. 5. Distribution of Senecio campylocarpus.

59 KANUNNAH Mark Wapstra, Ian Thompson and Alex Buchanan

woodland subject to seasonal inun­dation. The recent collection from Camp­bell Town is from the grassy banks of the river and from seasonal rocky rapids at the water’s edge. The species is likely to be more widespread than currently indicated by the paucity of records. It is common in Victoria, and also occurs in disturbed sites. It is similar to S. quadridentatus but differs from this species by its sparsely haired to glabrous leaves and stems, broader leaves tapering distinctly to each end, broader phyllaries reflexed rather than spreading at maturity, shorter florets with more corolla- lobes, curved achenes and the smaller taproot and fleshier secondary roots. The receptacle undergoes relatively little Fig. 6. Distribution of Senecio elegans. expansion as the achenes develop and, because of this, the capitula often develop tipped bracts combined with the thick a more urn-shaped appearance than those and more or less hollow branches and the of other species. fleshy deeply divided leaves make it easily This species was previously known recognised. It is a native of South Africa. as S. glandulosus (DC.) Sch.Bip. but this Walsh (1999) reports apparent hybrids name has recently been shown to be between S. elegans and S. pinnatifolius from illegitimate. The new epithet alludes to near Portland and Wilsons Promontory the characteristic curved outer achenes in Victoria, which have more narrowly that appear more pronounced than in any lobed or subentire leaves and pale mauve other disciform species. to whitish ligules (rather than the usual rich purple). Such hybrids have not been *Senecio elegans L., Sp. Pl. 2: 869 reported from Tasmania. (1753) ‘purple groundsel’ (Fig. 6) Senecio extensus I.Thomps., In Tasmania the species is most widespread Muelleria 19: 150 (2004) on the east and north coasts (including ‘subalpine fireweed’ Bass Strait islands) but is apparently absent (Fig. 7) from the west and south coasts. This is an Senecio extensus grows to 0.5 m. It is almost wholly coastal species (usually on readily distinguished by its long calycular dune sand) and has distinctive crimson to bracteoles. Its glabrous, lustrous achenes purple (or occasionally white) ligules. Even also usually help to distinguish this when not in flower, the broad cup-shaped species; however, a few collections from involucral buds with prominently black- Victoria with hairy achenes have recently

60 An Illustrated and Annotated Key to the Tasmanian Species of Senecio KANUNNAH

georgianus. As such, it is possible that S. georgianus is not present in Tasmania, but has been included in the key because of the Gunn collection. Although discoid, in other aspects of its morphology it conforms to the disciform group of Australian Senecio. It resembles S. gunnii vegetatively. Herbarium labels (from mainland specimens) suggest that it occurs at moderate altitudes and may be an autumn flowering species.

Senecio glomeratus Desf. ex Poir., Encycl. Suppl. 5: 130 (1817) ‘purple fireweed’ (Fig. 8) This species grows to 2 m and is wide­ Fig. 7. Distribution of Senecio extensus. spread in Tasmania in a range of habitats, at various elevations, and it often occurs been found. In Tasmania this species in disturbed sites. It is sometimes is only known from a single record confused with S. hispidulus because collected in 1984 (from Mackenzies Tier, both species have similar-sized capitula; on the Central Plateau). It is widespread however, the latter are more slender, in grasslands, herbfields and open shrub­ always green and never cobwebby, con­ lands in subalpine areas in New South tain fewer florets on longer peduncles Wales and Victoria, so it is likely to be and fewer and generally shorter calycular more common in Tasmania than currently bracteoles; and the upper-stem leaves recognised. have only coarse hairs. Two subspecies of this species are Senecio georgianus DC., Prodr. 6: 371 recog­nised, largely separated on the (1838) ‘grey fireweed’ dimen­­sions and characters of the This species has been recorded only achenes. Hybridisation between either once for Tasmania and, like all mainland S. hispidulus and S. minimus and either records of this species, this was in the of the two sub­species of S. glomeratus 1800s. The single Tasmanian collection is likely and it may be difficult to is apparently that of Gunn, held at Kew, distinguish such hybrids from S. and is simply labelled ‘Van Diemen’s glomeratus subsp. longifructus. However, as L a nd’. L ater i n h is c areer Gun n for warded S. hispidulus and S. minimus have narrower mainland col­lections of other collectors capitula than S. glomeratus, one would to Hooker. J.D. Hooker described Erechtites expect hybrids to have capitula that are candicans from this Gunn material, noticeably narrower than those of subsp. later recognised as synonymous with S. longifructus.

61 KANUNNAH Mark Wapstra, Ian Thompson and Alex Buchanan

S. glomeratus subsp. glomeratus subsp. longifructus unidentified subspecies

Fig. 8. Distribution of Senecio glomeratus.

62 An Illustrated and Annotated Key to the Tasmanian Species of Senecio KANUNNAH

Senecio glomeratus subsp. glomeratus ‘shortfruit purple fireweed’ This subspecies has numerous, crowded, small and often purple capitula sur­ rounded basally by many cobwebby caly­cular bracteoles. Often a rather tall plant in forest environments, it some­ times grows near water and then is sometimes sympatric with subsp. longi­ fructus. It is likely that hybridisation takes place between subspecies in these environments, and this is a probable reason for difficulties in assigning some specimens to either subspecies (inter­ mediate specimens have been col­lected on the Bass Strait islands). Fig. 9. Distribution of Senecio gunnii. Senecio glomeratus subsp. longifructus I.Thomps., Muelleria Senecio gunnii (Hook.f.) Belcher, 19: 148 (2004) Ann. Miss. Bot. Gard. 43: 60 (1956) ‘longfruit purple fireweed’ ‘mountain fireweed’ This subspecies grows adjacent to streams (Fig. 9) and swamps (sometimes in coastal areas This species grows to 1 m and it is such as river mouths and estuaries). Apart generally a species of higher elevations, from the characters in the key, subsp. widespread in north-eastern, central longifructus tends to be a shorter plant and southern Tasmania, most often in than subsp. glomeratus and appears to be Eucalyptus delegatensis and E. coccifera more consistently associated with water. forest/woodland. It resembles S. quadri­ Inflorescences generally have fewer and dentatus in the type and density of the less congested capitula with over­topping indumentum, but it differs in having more pronounced. The capit­ulum involucre broader, narrow-elliptic leaves, phyllaries is less commonly all purple although this with more convex stereomes, bisexual may be simply because it is more often in florets with 5-lobed corollas rather than shaded environments. Outer achenes of 4-lobed, female florets with larger corolla subsp. longifructus are often greenish, olive lobes and more sparsely haired and non- or brown, whereas others are medium lageniform achenes. brown. In contrast, achenes of subsp. glomeratus are commonly all medium to dark red-brown.

63 KANUNNAH Mark Wapstra, Ian Thompson and Alex Buchanan

Senecio hispidissimus I.Thomps., Muelleria 19: 138 (2004) ‘coarse fireweed’ (Fig. 10) This species is similar to S. squarrosus but is more densely coarse-hairy, and has smaller capitula with usually fewer phyllaries. It is also similar to S. hispidulus but is more densely coarse-hairy and with usually broader capitula and longer phyllaries that are purple or that have an apical zone that is purple. A few collections from the north-west coast of Tasmania have unusually short capitula and achenes. It is generally a lowland species, rep­ resented by only a few collections from Fig. 11. Distribution of Senecio hispidulus. scrub, dune and heath vegetation, close to the north and east coast. The widespread Senecio hispidulus A.Rich., Voy. distribution of these records indicates that Astrolabe 2: 94 t.34 (1834) this species is likely to be more common ‘rough fireweed’ than currently indicated. (Fig. 11) Senecio hispidulus is an erect herb that grows to 1.5 m. It is widespread in Tas­ mania, mainly in eastern, southern and north-eastern parts at lower elevations. It has been possibly previously confused with other jagged-leaved taxa such as S. glomeratus, S. biserratus and S. hispidissimus. Involucres of this species mostly com­ prise 11–14 phyllaries, but occasional plants have involucres of predominantly 9 or 10. Achenes of this species are usually hairy but occasional populations have plants with glabrous achenes.

*Senecio jacobaea L., Sp. Pl. 2: 870 (1753) ‘ragwort’ (Fig. 12) Ragwort is one of the state’s worst agri­ cultural weeds and is known to cause Fig. 10. Distribution of Senecio hispidissimus. death by liver damage in stock. It is subject

64 An Illustrated and Annotated Key to the Tasmanian Species of Senecio KANUNNAH

Fig. 12. Distribution of Senecio jacobaea. Fig. 13. Distribution of Senecio leptocarpus. to a Statutory Weed Management Plan Senecio leptocarpus DC., Prodr. under the Tasmanian Weed Management 6: 372 (1838) ‘western groundsel’ Act 1999. (Fig. 13) Plants are biennial and only form This subalpine species is easily recognised rosettes in the first year. These rosettes by its distinctive leaf morphology. It is a r e d i s t i n c t i v e a n d u n l i k e l y t o b e c o n f u s e d widespread on western, southern and with any other species. The irregularly some central northern mountains. A divided second-year stem leaves are dis­ record from Mt Rumney near Hobart tinctive. It is a native of Europe but is now (collected in 1929 by F.H. Long) is well established in most parts of the world. outside the expected range of the species. The species is widespread in Tasmania The record is questionable as the species occur r i ng mai n ly at lower elevat ions, and has not been subsequently recorded from is often associated with major centres of this part of the state and Mt Rumney is cultivation. It can also be found at higher a low altitude hill supporting grassy dry elevations in relatively undisturbed sclerophyll forest. sites. The paucity of herbarium records is typical of common and widespread Senecio linearifolius A.Rich., Voy. weeds, so the distribution map is not a Astrolabe 2: 129 (1834) true indication of its current widespread ‘fireweed groundsel’ distribution. (Fig. 14) The species is an aromatic perennial, often weakly shrubby, which grows to 2 m. The taxonomic revision of Thompson

65 KANUNNAH Mark Wapstra, Ian Thompson and Alex Buchanan

S. linearifolius var. linearifolius var. arachnoideus var. denticulatus var. latifolius unidentified subspecies

Fig. 14. Distribution of Senecio linearifolius.

66 An Illustrated and Annotated Key to the Tasmanian Species of Senecio KANUNNAH

(2004b) recognised nine varieties of S. although capitula may be longer and ray linearifolius, of which four are known florets more numerous than the couplet from Tasmania. These varieties can be requires. It is likely to occur only on the coast. distinguished mainly by leaf characters. Only the common and wide­spread var. Senecio linearifolius var. linearifolius has been adequately collected. arachnoideus I.Thomps. Muelleria Further collecting of material of the 20: 98 (2004) other varieties is necessary to gain a ‘cobweb fireweed groundsel’ better understanding of their features, This taxon is only known in Tasmania any intergrading between varieties, from three sites: Mayfield Beach on the and a clearer under­standing of their state’s east coast where it occurs in relative distribution. abundance, Tessellated Pavement on the Tasman Peninsula, and Montagu Swamp Senecio linearifolius var. in the north-west. It is likely to also occur linearifolius along rocky coastlines along eastern Tas­ ‘fireweed groundsel’ mania. On the mainland the variety grows This taxon commonly colonises disturbed in forest and coastal scrub. ground, e.g. clearfelled forestry coupes and Although there is a little overlap in margins of recently constructed roads and dimensions and numbers, capitula in var. tracks. It often forms dense thickets up to arachnoideus are generally larger (3.5–4.5 mm 1.5 m. It is widespread throughout Tas­ long, 1.5–2.5 mm diameter) than in var. mania, although most commonly in higher denti­culatus, var. linearifolius and var. latifolius; rainfall areas. The lack of records for some and number of ray florets is also generally parts of the state probably reflects the greater (more often 6–8). Immature leaves usual problem of common species not and stems are commonly clothed with a being adequately collected. It is readily more or less dense white wool early dis­tinguished by the dark green, very narrow in development; upper-stem leaves and long leaves with smooth margins and mostly narrow to very narrow-elliptic relatively inconspicuous venation. The (occasionally wider), to 12 cm long, with secondary venation on the lower surface is length:width ratio 4.5(–6–12); margin of not raised or only slightly raised and tert­iary stem leaves mostly denticulate to dentate venation is not usually discernible. (but sometimes entire to callus-denticulate), This variety hybridises with S. minimus not revolute, frequency of teeth 2–5 per in Victoria and Tasmania. A study of this cm; upper surface of leaves with venation hybrid on Mt Macedon in Victoria is docu­ sometimes strongly impressed, the surface mented by Thomas (2004). Such hybrids at first usually appressed-cobwebby, glab­ will key to Senecio linearifolius if ray florets rescent; lower sur­face of leaves with are present. Ligules of these florets would be scattered, weak, coarse spreading hairs or smaller and narrower than the range of sizes moderately cobwebby (hairs variably fine occurring in S. linearifolius (mostly 0.5–4 mm or coarse-based), glabrescent, secondary long). Another hybrid, S. pinnatifolius var. venation sharply raised and tertiary lanceolatus X S. biserratus, may also key here venation distinct.

67 KANUNNAH Mark Wapstra, Ian Thompson and Alex Buchanan

There is a gradation in var. arachnoideus Marys Pass area. On the mainland it occurs from northern New South Wales to at moderate to high altitudes and the Tas­ south-east Tasmania in the degree of manian collections are from steep slopes cob­webbiness of the leaf undersurface, in eucalypt forest at lower elevations. dentition of the leaf margins, and achene Senecio linearifolius var. latifolius has indumentum (grading to papillose-hairy upper-stem leaves that are commonly achenes further south). lanceolate and with a low length:width ratio, broad-cuneate to cordate at the base Senecio linearifolius var. with auricles continuous with the lamina, denticulatus I.Thomps. Muelleria the lower surface usually glabrous (rarely 20: 93 (2004) cobwebby) and with distinct (sharply ‘toothed fireweed groundsel’ raised) reticulate venation. Capitula are at This taxon is similar in habit to var. the smaller end of the range for the species linearifolius but appears to be much less (2.5–4.0 mm long, 1.0–1.6 mm diameter). wide­spread. The variety is most prevalent Some specimens are intermediate between in the north-east in dry to wet sclerophyll this variety and var. denticulatus. forest, with herbarium records from the eastern Bass Strait islands, the St Marys Senecio longipilus I.Thomps., area and the northern tip of Maria Island. Muelleria 19: 193 (2004) More recently the variety has been ‘longhair fireweed’ collected from the East Risdon Nature (Fig. 15) Reserve near Hobart, where it is sympatric This species grows to 0.5 m and occurs in with var. linearifolius. Although similar in far south-eastern New South Wales and in habit to var. linearifolius, the leaf margins northern Tasmania. There are three spec­ of stem leaves are always denticulate, imens in the Melbourne Herbarium (with secondary venation of the lower surface none held at the Tasmanian Herbarium). is more prominent and tertiary venation One was collected from near Perth, South is more distinct. There is a possibility Esk River, whereas the locality for the of intergrading with var. linearifolius (as other two is unclear. On the mainland recorded east of Melbourne) and var. the species occurs in sand or loam soils arachnoideus (as recorded near Eden, in grassland, herbfield, shrubland and New South Wales). Note that leaves woodland, mostly at elevations above of secondary inflorescence branches 1000 m but also in lowland areas. If may be sufficiently reduced such that the locality given was accurate, the denticulations do not show. Tasmanian record indicates a lowland distribution in this state. Senecio linearifolius var. latifolius It is distinguished from other species I.Thomps., Muelleria 20: 96 (2004) with broad capitula by the relatively long ‘broadleaf fireweed groundsel’ (1–2 mm) coarse hairs on stems, leaves and This taxon is localised in north-eastern bracts, and the relatively long bracts and Tasmania based on three collections from calycular bracteoles. Phyllaries are fewer the Lower Marsh Creek-Elephant Pass-St than in S. macrocarpus and are usually

68 An Illustrated and Annotated Key to the Tasmanian Species of Senecio KANUNNAH

Fig. 15. Distribution of Senecio longipilus. Fig. 16. Distribution of Senecio macrocarpus. fewer than in S. squarrosus. The pappus old record from northern Tasmania (South is usually relatively densely bristly and Esk River area close to Launceston/Perth). relatively long, and it commonly exceeds On the mainland it typically grows in the florets by c. 1 mm, obscuring them low-lying areas, and has been recorded at anthesis. Pappus bristles are more from basalt-derived clay or clay-loam soils scabrid-barbellate (i.e. with small pro­ in grassland, sedgeland and woodland. jections as seen under x 20 or greater This species is readily recognisable by its magnification) than in other related narrow-linear branch-leaves, small number species. Compared to S. squarrosus the of very large capitula, and long, densely stereomes of the phyllaries are broader, papillose-hairy, lageniform achenes. and this distinction is most evident in the distal 1.5 mm of the phyllary. Senecio microbasis I.Thomps., Muelleria 19: 175 (2004) Senecio macrocarpus Belcher, ‘narrow fireweed’ Muelleria 5: 119 (1983) (Fig. 17) ‘largefruit fireweed’ This species grows to 0.6 m. It is similar (Fig. 16) to S. phelleus but differs in narrower leaves Senecio macrocarpus grows to 0.6 m. It near the base of the plant, leaf-bases never is listed as extinct on the Tasmanian sagittately auriculate, capitula narrower Threatened Species Protection Act 1995 and and with fewer florets, phyllaries thinner as vulnerable on the Commonwealth and finally reflexed, corolla lobes fewer and Environment Protection and Biodiversity Conser­ less thickened apically, and the achenes vation Act 1999. It is represented by a single with a more slender neck. It could also be

69 KANUNNAH Mark Wapstra, Ian Thompson and Alex Buchanan

Fig. 17. Distribution of Senecio microbasis. Fig. 18. Distribution of Senecio minimus.

confused with S. prenanthoides but differs in throughout Tasmania at most elevations. that the lower-stem lacks coarse hairs and In Tasmania, prior to the major review the achenes are shorter and not distinctly of Senecio, many specimens (of several lageniform. It is currently known from species) are likely to have been erroneously a few scattered localities in the south attributed to this species. This species around Hobart, and in the southern and often forms dense shrubby stands on northern Midlands. The quite widespread disturbed sites such as roadsides and clear- distribution of these records indicates that felled coupes. this species is likely to be more common than the few records suggest. Senecio odoratus Hornem., Hort. Bot. Hafn. 2: 809 (1815) Senecio minimus Poir., Encycl. Suppl. ‘scented groundsel’ 5: 130 (1817) (Fig. 19) ‘shrubby fireweed’ This species is a shrubby plant that grows (Fig. 18) to 1.7 m, and is unlikely to be confused with Senecio minimus grows to 2 m. It is readily any other species due to its distribution, identified by inflorescence with numerous, which is almost wholly coastal, its glaucous small, slender capitula, and large leaves and aromatic character, large entire leaves, with more or less regular, crowded discoid capitula, small number of involucral denticulations and distinct reticulate bracts, and the prominently bell-shaped venation. It is most common on fertile corollas. It occurs mainly in the north of sites, e.g. rich soils in moister sites such as the state, including the Bass Strait islands, beside swamps and streams, and occurs and also on the north-west and west coast,

70 An Illustrated and Annotated Key to the Tasmanian Species of Senecio KANUNNAH

Fig. 19. Distribution of Senecio odoratus. Fig. 20. Distribution of Senecio papillosus. with a single record from the south at Senecio pectinatus DC., Prodr. 6: 372 Actaeon Island near Southport (although (1838) var. pectinatus the identification of this collection has not ‘yellow alpine groundsel’ been confirmed). Senecio odoratus grows on (Fig. 21) rocky slopes, clifftops, or sand dunes in This variety is endemic to Tasmania, occur­ shrubland, woodland and forest. ring on southern, central and north-eastern Senecio papillosus F.Muell., Trans. mountains, including Mt Wellington. Philos. Inst. Vict. 2: 69 (1857) Some specimens from Ben Lomond (e.g. M.G.Noble 28274 ‘warty groundsel’ ; Tas­manian Herbarium) were recently included by Thompson (Fig. 20) (2004c), and con­sequently Buchanan This is one of the subalpine species (2005), in var. major based on their capitular endemic to Tasmania. However, this dimensions that exceeded those presented species appears to be one the most res­ by Belcher (1996) and later Thompson tricted of the highland species, so far (2004c) for var. pectinatus. In a later paper known only from Adamsons Peak, Mt La Thompson (2006) referred these specimens Perouse, Mt Bobs and Pindars Peak. The to var. pectinatus because of their foliar species is distinctive because the upper morphology. In the absence of a clear-cut leaf surface is densely studded with clear discriminating character, however, the short straight or curved multicellular Ben Lomond form remains taxonomically hairs with tuberculate bases. problematic. On the basis of Thompson’s reassessment, var. major is considered endemic to the Australian mainland.

71 KANUNNAH Mark Wapstra, Ian Thompson and Alex Buchanan

Fig. 21. Distribution of Senecio pectinatus. Fig. 22. Distribution of Senecio phelleus.

Senecio phelleus I.Thomps., Muelleria small taproot, often sagittate leaf-bases, 19: 171 (2004) ‘rock fireweed’ shorter capitula, always glabrous peduncles (Fig. 22) and capitula, corollas of bisexual florets This species grows to 1.5 m. It is represented 5-lobed, with lobes more thickened, and by two herbarium collections in Tasmania: achenes not lageniform. It is also similar to S. one from near Hobart and the other from prenanthoides in habit, indumentum of leaves Betsey Island. Recent collections from and bracteole number, but differs in having Tinderbox Hills, south of Hobart, and the lower-stem region with an appressed- Knocklofty, west of Hobart, indicate that cobwebby indumentum, more florets per it is probably more widespread in the capitulum, secondary roots not tuberiform, state than currently recognised. It occurs leaf-bases commonly sagittate, and achenes in south-eastern Australia, from Bathurst shorter and not lageniform. It could also in central-eastern New South Wales south be confused with S. microbasis but its lower to eastern Victoria and westwards to leaves are broader, its capitula are larger and Adelaide in south-eastern South Australia, with more florets, the leaf-bases are sagittate, and disjunctly further west on the Eyre and the neck of achenes is less slender. Peninsula. It grows in sandy or heavy soils, Senecio pinnatifolius A.Rich., Voy. often in rocky sites in heathland and in, Astrolabe 2: 117 (1834) usually, drier forest and woodland. (Fig. 23) It may previously have been identified as S. quadridentatus and more recently as either Five varieties of S. pinnatifolius are recognised S. prenanthoides or S. microbasis. It is similar in Tasmania, and together with S. spath­ulatus, to S. quadridentatus but differs in having a the infra-specific limits within the complex

72 An Illustrated and Annotated Key to the Tasmanian Species of Senecio KANUNNAH have been difficult to resolve. Most Tas­ branch leaves. Ligules are relatively short, manian specimens of Senecio previously not or hardly longer than the involucre labelled as S. lautus are S. pinnatifolius. in pressed specimens, and achenes are relatively short compared to those of var. Senecio pinnatifolius var. alpinus pinnatifolius and var. alpinus. Although (Ali) I.Thomps., Muelleria 21: 52 (2005) always finely dissected, there is variation ‘highland groundsel’ from long filiform primary and secondary This variety grows to 1 m, and is com­ segments to those with smaller intricately monly erect or suberect, or ascending divided often tri-pinnatisect leaves with from a horizontal rhizome and then the segments rather crowded. Forms of var. aerial branches are few or absent. It occurs lanceolatus with bi-pinnatisect leaves, in moderate to high altitudes in forest, some of which occur on the Bass Strait woodland and alpine meadows. The islands, resemble var. capillifolius but these distribution map shows only a limited forms have different phyllary morphology, number of specimens held at the Tasmanian their upper-stem region and inflorescences Herbarium that have been identified as are less congested, and the ligules are this variety, although it is expected to be longer than the involucre. more widespread. This variety is largely separated geographically and altitudinally Senecio pinnatifolius var. from other varieties. It has oblanceolate lanceolatus (Benth.) I.Thomps., leaves with relatively distally positioned Muelleria 21: 49 (2005) marginal points or segments; however, ‘lanceleaf coast groundsel’ smaller-leaved forms are sometimes difficult This variety grows to 2 m, and is com­ to distinguish from var. pinnatifolius. Senecio monly erect, sometimes sprawling. It is pinnatifolius var. alpinus is also characterised widespread, mainly in coastal areas but by short curled hairs on both the peduncle occasionally inland in the south, east and and margin of calycular bracteoles. north. Only specimens from the eastern Bass Strait islands have been positively Senecio pinnatifolius var. identified as this variety in the collection capillifolius (Hook.f.) I.Thomps., at the Tasmanian Herbarium. Muelleria 21: 51 (2005) This variety differs from the other ‘fineleaf coast groundsel’ varieties most significantly in phyllary This variety grows to 0.8 m, and is erect or morphology; in particular the relatively sprawling. It is currently only known from large disparity in width between the the Bass Strait islands including some small stereomes of the inner and outer phyl­ and close to shore islands off the north-east laries (measured c. 1 mm below the apex); coast. This variety is distinctive because and the relatively broad hyaline margin of of its much-dissected leaves, succulent the outer phyllary in the distal third (Fig. branches (generally quite flattened after 45). A bold purple chevron (upside-down pressing), and congested corymbiform V), visible with the naked eye or with low inflorescences that are held only a short power magnification, usually delineates distance above the often congested upper- the stereome of inner phyllaries. Also

73 KANUNNAH Mark Wapstra, Ian Thompson and Alex Buchanan

S. pinnatifolius var. pinnatifolius var. alpinus var. capillifolius var. lanceolatus var. maritimus unidentified subspecies

Fig. 23. Distribution of Senecio pinnatifolius.

74 An Illustrated and Annotated Key to the Tasmanian Species of Senecio KANUNNAH in this variety the leaves tend to have a basally, smaller calycular bracteoles relatively high number of marginal points, and differently coloured achenes (olive- the number of capitula per inflorescence brown and golden rather than reddish is often high (up to 40), and the taproot and brown). The var. maritimus can be is poorly developed. In dried specimens, difficult to distinguish from S. spathulatus the distal portion of the stereome that the var. spathulatus, which occupies similar chevron outlines may be pale beside the coastal habitats (see also comments under chevron rather than green. S. spathulatus, 19a). Senecio pinnatifolius var. The degree of leaf division can vary maritimus differs from coastal forms of var. enormously in some populations; however, pinnatifolius that are widespread along the populations of purely serrate-leaved plants east coast of Australia including Tasmania, or purely pinnatisect-leaved plants also by having fleshier leaves, generally fewer occur. Plants of var. lanceolatus growing on leaf segments (if present) and with a coastal dunes have smaller more succulent lower length:width ratio, shorter achenes leaves with reduced numbers of marginal relative to the length of the phyllaries, points, compared to plants growing and of upper-branch leaves (excluding any slightly more inland. segments) broader near the base and never Senecio pinnatifolius var. lanceolatus and S. developing strap-like basal segments. biserratus form an occasional hybrid that was Senecio pinnatifolius var. described as S. Xorarius (Black 1928). Only pinnatifolius one Tasmanian specimen at the Tasmanian ‘common coast groundsel’ Herbarium (collected by L. Rodway in 1893 from the mouth of the Little Henty This variety grows to 1.5 m and is erect, River on the west coast) is known. Hybrids sprawling or prostrate. It grows in a range between other varieties of S. pinnatifolius of environments including dry hills and and S. biserratus or other disciform species, coastal dunes, in forest, woodland and such as S. minimus, are also likely to occur; scrubland, mainly in the state’s east and however, the hybridisation between S. south but also in scattered locations on the pinnatifolius var. lanceolatus and S. biserratus west and north coasts, including the Bass appears to be by far the most common. Strait islands, and a few inland locations, e.g. the Midlands. Senecio pinnatifolius var. maritimus This variety represents a complex of (Ali) I.Thomps., Muelleria 21: 54 (2005) subtly different forms that currently resist ‘western coast groundsel’ discrimination. A widespread form extends This variety grows to 0.4 m and is along the coasts of Queensland, New sprawling to prostrate. It is restricted to South Wales and eastern Tasmania. It has the west coast and King Island. Senecio somewhat succulent leaves and the rachis pinnatifolius var. maritimus can be difficult is usually narrowly oblanceolate. Achenes to distinguish from var. lanceolatus and var. are typically relatively long and slender, pinnatifolius. Compared to the mainland extending more than half the length of the form of var. maritimus, the Tasmanian phyllaries. Compared to S. pinnatifolius var. form has uppermost leaves more dilated maritimus its leaves are less fleshy, narrower

75 KANUNNAH Mark Wapstra, Ian Thompson and Alex Buchanan

basally, with generally more marginal this respect, as well as in the type of leaf points, and often with slender basal indumentum and capitular dimensions, segments, and its achenes are distinctly S. prenanthoides is similar to S. phelleus but longer and relatively slender, with finer, differs from that species by having slightly shorter hairs in narrower grooves. tuberiform roots, basal regions of stems with coarse hairs, auricles when present Senecio prenanthoides A.Rich., Voy. not sagittate or amplexicaul, phyllaries Astrolabe 2: 96 (1834) sometimes fewer and usually finally reflexed, ‘common fireweed’(Fig. 24) and achenes longer and lageniform. The leaf This species grows to 0.6 m. It was first shape in S. prenanthoides is diverse but most described in 1834 but was treated as characters are very consistent. synonymous with S. quadridentatus until recently resurrected by Thompson (2004a). Senecio primulifolius F.Muell., Trans. This is a widespread and common species, Philos. Inst. Vict. 2: 69 (1857) mainly in eastern Tasmania, growing in ‘showy alpine groundsel’ sandy and loamy soils in scrub, woodland (Fig. 25) and forest from sea-level to c. 1500 m. This is a subalpine species endemic to This is one of several species forming a Tasmania and is one the most restricted of rosette of leaves until the phase of rapid the highland species, occurring only on the elongation leading up to flowering. As southernmost mountains of the state. The flowering commences, leaves tend to be species has distinctive Primula-like leaves relatively crowded and are significantly with conspicuous venation. broader in the lower half of the plant. In

Fig. 24. Distribution of Senecio prenanthoides. Fig. 25. Distribution of Senecio primulifolius.

76 An Illustrated and Annotated Key to the Tasmanian Species of Senecio KANUNNAH

with stems arising from these horizontal structures to emerge above the surface of the water. This extensive growth habit has not been observed in S. squarrosus (Belcher and Albrecht 1994). Belcher and Albrecht (1994) also suggested that the smell emanating from bruised leaves (carrot- like in S. psilocarpus; tomato-like in S. squarrosus) may distinguish the species, but this has not been assessed by the authors.

Senecio quadridentatus Labill., Nov. Holl. Pl. 2: 48 t.194 (1806) ‘cotton fireweed’(Fig. 27) This is the distinctive grey-white, softly hairy, usually quite tall and erect plant of var­ ious habitats including disturbed sites such Fig. 26. Distribution of Senecio psilocarpus. as roadside batters, gardens and suburban streets. It is a widespread species in Tasmania Senecio psilocarpus Belcher & Albr., occurring from sea-level to higher altitudes. Muelleria 8: 113 (1994) The paucity of herbarium records is typical ‘swamp fireweed’(Fig. 26) of common and widespread species and the This species grows to 0.8 m. It is currently distribution map is not a true indication of represented by very few Tasmanian collections. It is historically known from Flinders Island and Cressy (as shown on map) and more recently (and not shown on map) from King Island (Nook Swamps), Dukes Marsh (central east) and Mt William National Park (far north-east), indicating a possibly much wider distribution than previously thought. Senecio psilocarpus most closely resembles S. squarrosus but has a sparser indumentum, shorter capitula and glabrous achenes. The two species have a similar distribution but S. psilocarpus has a stronger preference for aquatic habitats. It has been recorded from herb-rich wetlands. Associated with its aquatic nature, S. psilocarpus can develop long underground ‘rhizomes’ or decumbent stems that root at the nodes Fig. 27. Distribution of Senecio quadridentatus.

77 KANUNNAH Mark Wapstra, Ian Thompson and Alex Buchanan

how widespread it is. The usually narrow- but appears restricted to frontal dunes and linear, revolute leaves are typically numerous shifting sands, unlike the latter. along stems and are relatively crowded, and the precocious leafy axillary growth is Senecio squarrosus A.Rich., Voy. usually evident in axils above mid-stem as Astrolabe 2: 107 t.35 (1834) the initial flowering period commences. The ‘leafy fireweed’(Fig. 29) capitula are relatively slender. This species Senecio squarrosus grows to 0.8 m. It is is unlikely to be confused with any other widespread in south-eastern South Aust­ currently recognised taxa in Tasmania. ralia, southern Victoria and in north­ern and southern Tasmania. This species is listed as Senecio spathulatus A.Rich., rare (Schedule 5 of the Tasmanian Threatened Voy. Astrolabe 2: 125 (1834) var. Species Protection Act 1995), although the spathulatus widespread distribution combined with ‘dune groundsel’ (Fig. 28) its occurrence in several reserves and in Of the three varieties of S. spathulatus, only disturbed areas suggest a re-assessment of var. spathulatus is present in Tasmania where its conservation status is warranted. Around it is endem ic. At present it is k now n on ly f rom Hobart a form occurs with relatively narrow the southern and western coasts and from capitula and phyllaries predominantly King Island. This species is characterised 13. The more typical form from northern by short fleshy leaves, large fleshy capitula, Tasmania and the mainland has 16–20 and large achenes with a persistent pappus. phyllaries. Otherwise the Hobart form is S. spathulatus is sympatric and possibly typical of the species. Not uncommonly, hybridises with S. pinnatifolius var. maritimus, the corolla-lobes of S. squarrosus are purple

Fig. 28. Distribution of Senecio spathulatus. Fig. 29. Distribution of Senecio squarrosus.

78 An Illustrated and Annotated Key to the Tasmanian Species of Senecio KANUNNAH rather than yellow or yellowish-green. This The very long slender capitula and very coloration has not been recorded for other long lageniform achenes are distinctive. disciform species. Based on the few specimens collected, mid- stem leaves are oblanceolate to very narrow- Senecio tasmanicus I.Thomps., elliptic, 3–8 cm long, with length:width Muelleria 19: 158 (2004) ratio c. 6–15, entire or denticulate to coarse- ‘tasmanian fireweed’(Fig. 30) dentate, with phyllaries 8–12 mm long; and This species grows to 0.4 m. It is a Tas­ with up to 20 capitula per stem. m a n i a n en d em ic but h a s not b een r ec ord ed Although the species has been listed as since the mid-1800s and is possibly ‘extinct’ in Buchanan (2005), it is consid­ extinct. There are only two records for ered premature, on the basis of only two the species, the type collection by Archer collections, to list this species as threatened labelled Tasmania (date unknown) and under the Tasmanian Threat­ened Species another by R.C. Gunn from the property Protection Act 1995. The recent ‘rediscovery’ of ‘Formosa’ in the northern Midlands. The S. campylocarpus from the heart of Campbell most likely habitat is lowland plains Town lends weight to this argument. near swamps. The species may have been overlooked, but it is also likely that Senecio vagus F.Muell., Trans. Philos. its habitat has been severely modified Soc. Vict. 1: 46 (1855) subsp. vagus by land clearing since the 1800s. More ‘sawleaf groundsel’ (Fig. 31) focused attention in the field on entire- This species is represented by a single leaved, relatively short (less than 0.5 m) specimen at the Tasmanian Herbarium, specimens is recommended. collected in 1965 from Walkers Hill on

Fig. 30. Distribution of Senecio tasmanicus. Fig. 31. Distribution of Senecio vagus.

79 KANUNNAH Mark Wapstra, Ian Thompson and Alex Buchanan

Flinders Island by John Whinray. The subsp. eglandulosus, which occurs only on the Australian mainland, has glabrous phyllaries and achenes with hairs in lines along ribs.

Senecio velleioides A.Cunn. ex DC., Prodr. 6: 374 (1838) ‘forest groundsel’ (Fig. 32) Although widespread and often very common, this species is listed as rare (Schedule 5) on the Tasmanian Threat­ ened Species Protection Act 1995. It is a distinctive, robust species often more than 1 m tall, often glaucous and fleshy with distinctive amplexicaul leaves. Leaves are frequently light-green on upper surface and glaucous beneath. It often grows with other Senecio species on Fig. 33. Distribution of Senecio vulgaris. disturbed sites (often in the thousands) especially after fire, but populations are *Senecio vulgaris L., Sp. Pl. 2: 867 usually short-lived, disappearing with (1753) ‘common groundsel’ canopy closure. (Fig. 33) This distinctive species has lobed to pinnatisect somewhat fleshy leaves and strongly black-pigmented calycular bracteoles, and is unlikely to be confused with any other. Also distinctive is the abrupt transition in the corollas of florets from tube to limb, which occurs 1–1.5 mm below the apex. In disciform species this transition is extremely gradual. A native of Europe, it is now established virtually globally. The paucity of herbarium records is typical of common and widespread species, especially exotic species, and the distribution map is not a true indication of its distribution. It is mainly a weed of cultivation and suburbia.

Fig. 32. Distribution of Senecio velleioides.

80 An Illustrated and Annotated Key to the Tasmanian Species of Senecio KANUNNAH

Definition and illustration of terms All technical terms used in the key are indicated by bold type and are defined below (listed alphabetically) under rele­ vant broader headings, e.g. terms to describe leaf shapes and margins are found under the heading ‘leaf’. Terms defined separately are in italics. Achene: A dry one-seeded fruit not opening by valves or regular lines, often also called a cypsela (e.g. Curtis 1963; Walsh 1999). Achenes in Senecio can be divided into a carpopodium (the foot by which they attach), a longitudinally ribbed body and a pappus (Fig. 34). Papillose Fig. 34. General achene morphology showing (from bottom to top) carpopodium, body with hairs (small hair-like protuberances) are longitudinal ribs, pappus ring and pappus. often present in the grooves between the ribs, arranged lengthwise and forming Bract: A leaf-like structure that is sig­ lines or bands of varying density and nificantly smaller than the true leaves. width (Fig. 35). Immature achenes may There may be a clear distinction between have imperfectly developed hair bands, leaves and bracts or the change from leaf to while in over-mature achenes the hairs bract may be gradual. Although the stems may have been shed. The pappus is a of rosette-forming species in Tasmania ring of very fine bristles or hairs at the are not entirely leafless, full-sized leaves tip of the achene, which can be persistent are only found in the lower-stem region, but more often is caducous (shed as the if at all, and they are replaced by bracts achene matures). above mid-stem. Very small structures Achenes vary in shape (Fig. 35). They can subtending inflorescence branchlets and be cylindrical (parallel sides with flattened peduncles are also termed bracts, and ends), obloid (cylindrical but with rounded other more specialised bracts in Senecio are ends), ellipsoid (elliptic, tapering over the termed calycular bracteoles and phyllaries. whole length to narrow rounded ends) or lageniform (narrowly bottle-shaped, Calycular bracteoles: Small bracts that is, with the distal third more tapered arising from the receptacle of the capitulum, than the proximal third). The distinction and from the distal most part of the between lageniform and non-lageniform is sometimes partially arising from the end important for keying out disciform species. of the peduncle (Fig. 36). Long fine hairs Most achenes are straight, although outer arising from the margin of bracteoles in achenes can be distinctly curved (e.g. as in some species give the lower capitulum a S. campylocarpus). cobwebby or woolly appearance.

81 KANUNNAH Mark Wapstra, Ian Thompson and Alex Buchanan

A B C

D E F

G H I

Fig. 35. Detailed achene morphology (A–H adapted from Thompson 2004a; I from Belcher and Albrecht 1994). A. Narrow oblong-ellipsoid with papillose hairs in dense bands (S. biserratus). B. Narrow-obloid to narrow oblong-ellipsoid, hairs scattered or in dense bands (S. phelleus). C. Narrow-obloid to narrow-ellipsoid with relatively fine papillose hairs in lines or somewhat scattered (S. hispidulus). D. Narrow oblong-ellipsoid, glabrous (S. gunnii). E. Lageniform, the most curved achene of the disciform species, close-up of lines of short papillose hairs (S. campylocarpus). F. Lageniform with papillose hairs in dense bands (S. macrocarpus). G. Lageniform, extremely attenuate apically (S. tasmanicus; note that S. prenanthoides and S. quadridentatus have the same lageniform shape but with a shorter neck). H. Narrow-obloid, glabrous (S. psilocarpus). I. Narrow- obloid with papillose hairs in dense bands (S. squarrosus). No t t o s c a l e

82 An Illustrated and Annotated Key to the Tasmanian Species of Senecio KANUNNAH

5

3 4

2

1 2 1

A B

Fig. 36. A. Capitulum and peduncle: 1. peduncular bract; 2. peduncular bracteole; 3. calycular bracteole; 4. receptacle; 5. involucre. B. Capitulum shape change through time: 1. just prior to anthesis (flowering); 2. bulging basally towards fruit maturity.

A B C

Fig. 37. Tubular florets: corollas of central (left) and outer (right) florets: A. A discoid species (S. odoratus). B–C. Two disciform species, S. hispidulus (B) and S. dolichocephalus (C). Note: corollas of S. quadridentatus are similar but slightly shorter than those of S. dolichocephalus (a non-Tasmanian species).

83 KANUNNAH Mark Wapstra, Ian Thompson and Alex Buchanan

Capitulum (pl. capitula): The com­ Fleshy: Of leaves and roots, indicating pound reproductive structure in the daisy thickness due to tissue rather than fluid family, the flowerhead, in gardeners’ content (cf. succulent). Fleshy parts often language simply the flower (Fig. 36). It have an almost leathery texture and consists of a dense cluster of florets (tiny remain thick on drying. sessile flowers) placed on a common receptacle (the expanded summit of the Glaucous: Of surfaces, blue-green in peduncle) and surrounded by an involucre colour, usually due to a waxy bloom. The of phyllaries around the rim. As achenes fall bloom can usually be rubbed off and may away at maturity, the receptacle becomes be most evident in younger plants or on exposed but it is still possible to determine younger stems and leaves of older plants. how many florets were present by counting Indumentum (Fig. 41): The nature and the minute pits or indentations where the density of hairs on plant surfaces. Organs achenes were attached. without hairs are glabrous. Glabrescent In Senecio the corolla (collective term means becoming glabrous, usually with for petals) is of two basic types and age, through loss of hairs. Hairs may be florets are named on this basis. In tubular coarse or fine and individual plants may florets the corolla consists of a tube with have one type or both. Coarse hairs are 3 to 5 distal lobes (Fig. 37), whereas in thick, c. 0.1 mm diameter, multicellular ray florets it is a long strap-like structure and septate, with the partitions (septa) termed a ligule, which extends from a between the individual cells visible under very short tubular base. Senecio s p e c i e s a r e low microscopic magnification. When fresh categorised by the type of capitulum, of these hairs are transparent, straight and which there are three: radiate, disciform perpendicular to the surface. When dried and discoid. Radiate capitula (Fig. 38) can they become quite distorted but the septa be seen in the typical garden daisy, with often remain discernible. Coarse hairs a heart of tubular florets (disk florets) range in length from 0.2–2.0 mm and taper surrounded by ray florets with their to a short point. They may have a wispy radiating ligules. Non-radiate capitula do extension (resembling a fine hair) that in not have ray florets. They are categorised some cases can partially or totally obscure as disciform if the central florets are the coarser portion. When coarse hairs bisexual and the outer florets are female break off, the tubercle-like bases generally and, in Australian Senecio, the outer persist and the surface is called tuberculate. florets have a more slender and fewer- Fine hairs are white and entirely thread- lobed corolla, or discoid if all florets are like (c. 1/10 the diameter of coarse hairs) bisexual. In Tasmania the three discoid and have no visible internal structure species are Senecio georgianus, S. odoratus when magnified. Along stems, fine hairs and S. vulgaris. Examples of capitula are are commonly arranged longitudinally and presented in Figs 38–40. closely pressed to the stem (appressed). Distal: Remote from the point of origin or When fine hairs are dense and closely attachment; the free end, cf. proximal. appressed (obscuring all or most of the

84 An Illustrated and Annotated Key to the Tasmanian Species of Senecio KANUNNAH

A B

C

D

E F

G

Fig. 38. Capitula of various species of Senecio. Radiate capitula: A. S. elegans. B. S. velleioides. C. S. linearifolius var. linearifolius. D. S. albogilvus. E. S. leptocarpus. F. S. angulatus. G. S. jacobaea. No t t o s c a l e

85 KANUNNAH Mark Wapstra, Ian Thompson and Alex Buchanan

A B

C D

E

F

G H

Fig. 39. Capitula of various species of Senecio. Disciform capitula. A. S. quadridentatus. B. S. gunnii. C. S. glomeratus subsp. glomeratus. D. S. campylocarpus. E. S. biserratus. F. Hybrid between radiate and disciform species (possibly S. biserratus or S. minimus and S. linearifolius var. arachnoideus or S. pinnatifolius var. pinnatifolius). Note the smaller ligules (compare with figure 38C). Discoid capitula. G. S. vulgaris. H. S. odoratus. No t t o s c a l e

86 An Illustrated and Annotated Key to the Tasmanian Species of Senecio KANUNNAH

A B C

Fig. 40. Disciform capitula (examples drawn from pressed material). A. Involucre of c. 8 phyllaries (S. minimus). B. Involucre of c. 13 phyllaries (S. glomeratus subsp. glomeratus: note basal woolliness). C. Involucres of c. 20 phyllaries (S. macrocarpus: note spreading calycular bracteoles in this species. underlying surface) the indumentum is inflorescences commonly develop on leafy called cottony. When fine hairs (or wispy branches that arise immediately below extensions of coarse hairs) are tangled the base of the primary inflorescence. and sparse or moderately dense (partially Overtopping is used to describe inflor­ obscuring the underlying surface), the escences where lateral capitula or clusters indumentum is called cobwebby. If tangled extend above the central capitulum or and dense and more or less completely cluster. This architecture is common obscuring the underlying surface, the among the disciform species and is variable indumentum is called woolly. in extent depending on the species.

Inflorescence: Although technically Involucre (adj. involucral): A ring of a capitulum is an inflorescence (a group specialised bracts (phyllaries) surrounding or clustered arrangement of flowers), in the florets of a capitulum. The diameter the daisy family the term inflorescence of the involucre is defined in this paper usually refers to the arrangement of as the diameter in unpressed specimens groups of capitula. A unit inflorescence is measured a little more than halfway along a cluster of capitula at the end of an axis the involucre. At this point the diameter is where all associated branch structures are more or less constant through the phases leafless (Fig. 42). A primary inflorescence of development (the lower half of the is a unit inflor­escence terminating a stem involucre often expands substantially after (in some rosette-leaved species, a single fertilisation to accommodate developing unbranched stem with one or more capitula fruits and the diameter of the apex can form the unit inflorescence). Secondary be affected by reflexion of the phyllaries).

87 KANUNNAH Mark Wapstra, Ian Thompson and Alex Buchanan

A

B Fig. 42. Inflorescence architecture. The primary unit inflorescence with capitula represented by circles and the initial capitulum shown as a closed circle. A secondary inflorescence, defined by presence of leaves, is also shown (cluster of capitula represented by a square). Moderate overtopping is demonstrated in this example.

leaves or uppermost or lowermost leaves), Fig. 41. Indumentum. A. Fine hair (left) and unless otherwise specified. coarse, septate hair (right). B. Coarse hairs showing variation in length and degree of Leaves of most species of Tasmanian wispy extension (hairs desiccated and variously Senecio are not truly petiolate (petiole is a collapsed and crumpled as seen in herbarium leaf stalk), although often their leaves are specimens). (x 30). attenuate (tapering to a narrow base). If the base of the leaf clasps the stem to some In pressed specimens, the involucre often degree, the leaf is said to be amplexicaul becomes flattened, so allowance needs to (Fig. 43). Leaf-bases can be auriculate (with be made for this. auricles or ear-shaped lobes at their base), sagittate (with acute auricle lobes directed Leaves: Within a single plant of Senecio backwards), cuneate (wedge-shaped, with leaves will tend to vary in size, shape straight sides converging at the base) or and degree of dissection between lower truncate (cut off squarely, with an abrupt and upper regions. Leaves of secondary transverse end). The apex of undivided inflorescences will tend to be smaller leaves is typically acute. Although there is and less dissected than stem leaves. It some variation in the shape of leaf apices is important therefore that leaves from in Australian Senecio, it has not generally the same region of a plant are used when been found to be a useful character for comparing species. In this key, references to discriminating taxa. leaves apply to the leaves that arise from Leaf shapes (Fig. 43) mentioned in the the middle third of stems (i.e. not branch key are defined as follows: elliptic (evenly

88 An Illustrated and Annotated Key to the Tasmanian Species of Senecio KANUNNAH

F B D E

A C

G H

Fig. 43. Leaf outlines (leaves from midstem region x 0.5; basal auricles not included except as indicated (G–H). A. Undivided except for a few proximal lobes, margins entire (S. phelleus). B. Undissected, margin scattered-denticulate (S. prenanthoides). C. Undissected, margin crowded- denticulate (S. minimus). D. Coarse-dentate to deeply lobate, margin denticulate, segments and dentition proximal (S. hispidulus). E. Pinnatisect, once divided (S. pinnatifolius). F. Bipinnatisect, twice divided (S. pinnatifolius). G. Base of leaf showing small, entire auricles, non-amplexicaul (upperstem leaf of S. quadridentatus). H. Base of leaf showing large, dissected auricles, somewhat amplexicaul (S. biserratus). oval like a flattened circle), ovate (egg- used to further qualify leaf shape. The shaped, broadest in the proximal half), term length:width ratio (l:w ratio) refers lanceolate (three or more times as long as to the ratio between the length of the leaf broad, broadest in the proximal half), linear measured from apex to base of petiole and (very narrow in relation to length, with the width measured at right angles to the axis at sides mostly parallel), oblanceolate (reverse the widest points (several leaves should be lanceolate, attached by the narrower end), measured to obtain an average l:w ratio). and spathulate (spoon-shaped, broad at Leaf margins can be entire (smooth, the tip and narrowed towards the base). without teeth or other interruptions) The terms narrow and broad are often or variously lobed, divided or toothed.

89 KANUNNAH Mark Wapstra, Ian Thompson and Alex Buchanan

Fig. 44. Phyllary morphology: five consecutive phyllaries of an involucre demonstrating the three major types of phyllary. From right to left: inner (margin broad, stereome with two resin ducts); outer (margin narrow, stereome with one resin Fig. 45. Distal portion (c. 1 mm) of outer duct); inner (stereome with only one resin (left hand side in each pair) and inner (right duct); outer and intermediate (margin narrow hand side in each pair) phyllaries of on one side, broad on the other). S. pinnatifolius var. lanceolatus (above) and var. pinnatifolius (below).

Margins can be recurved (curved under Leaves with less severe dissection towards the midrib but not sufficiently to (dentition of the margin) are termed den­ hide the lower leaf surface), revolute (rolled tate (with spreading, evenly triangular under towards the midrib so as to hide teeth), denticulate (finely dentate with part of the lower leaf surface) or flat. Major smaller teeth), serrate (unevenly triangular divisions of leaves are termed segments. teeth angled forwards), serrulate (finely A notch or major indentation of the leaf serrate with smaller teeth) or callus- margin is called a sinus. Teeth, lobes and denticulate (with small points protruding segments are collectively referred to as but with little or no sinus formation). marginal points. Venation refers to the arrangement of The leaf blade is called the lamina. The veins in a leaf. The midrib or midvein is following terms are used to describe the termed the primary vein and is usually degree of division (incursion of the sinuses): the most prominent. Veins arising from coarse-dentate (30–50%), lobate (50–75%) the primary vein are termed secondary, and pinnatisect (> 75%). Bipin­natisect and veins arising from these are tertiary. describes pinnatisect leaves where primary Venation can be reticulate (forming an segments themselves are deeply divided. interconnected network of small veins). Tripinnatisect indicates a further order of division. Division can be regular (most Peduncle: The stalk bearing a single species) or irregular (as in S. jacobaea). capitulum (Fig. 36). Peduncles gradually

90 An Illustrated and Annotated Key to the Tasmanian Species of Senecio KANUNNAH

A B C

Fig. 46. Root systems. A. Taproot well-developed, stouter than secondary roots (S. hispidulus). B. Taproot slender, not stouter than fleshy secondary roots (S. phelleus); C. Taproot slender or lost, secondary roots very fleshy and slightly tuberiform (S. prenanthoides). (x 0.5). increase in length prior to and during many involucres; they are half and half flowering. Bases of peduncles and branch­ with the margin on one side overlapping lets are subtended by bracts. Peduncles are and on the other being overlapped. In S. bracteolate with up to 5 bracts scattered pinnatifolius in particular it is important along the peduncle and 3–12 calycular to recognise these distinctions. Notably, bracteoles inserted on or just below the in S. pinnatifolius var. lanceolatus, there receptacle, and typically more or less is an inverted V-shaped pigmentation appressed around the base of the involucre. mark delineating the distal portion of Peduncles, inflorescence branchlets and the stereome of the inner phyllaries. This the margins of bracteoles are often woolly mark is termed a chevron herein (Fig. 45). or cobwebby, or sometimes coarse- hairy, and this indumentum is variably Proximal: Nearer to the point of attach­ persistent. ment, cf. distal.

Phyllaries (Fig. 44): The specialised bracts Rosette (of leaves): Several to many surrounding the florets of a capitulum. leaves radiating from the base of the stem. Collectively they form the involucre. Roots: The root system (Fig. 46) may Phyllaries consist of an herbaceous lamina consist of a single stout taproot (the primary (the stereome) which is tinged green or root descending straight down), which may purple and a hyaline (thin, translucent, branch into a number of slender secondary colourless) margin. One or two roots, or the taproot may be unbranched longitudinal resin ducts are usually evident but may be slender and be accompanied by in stereomes. Phyllaries overlap along secondary roots of equal thickness arising these margins and so can be categorised separately from the base of the stem. Root as inner phyllaries or outer phyllaries. systems can also comprise secondary As well, intermediate phyllaries occur in

91 KANUNNAH Mark Wapstra, Ian Thompson and Alex Buchanan

roots only, without a taproot being Stems: Stems of most species are erect, present. The relative size (fleshiness) of occasionally somewhat sprawling, and the primary roots compared to secondary in species mainly at higher altitudes or roots is variable, and is an important along the coast, sometimes creeping distinguishing character for many disc­ and/or ascending before becoming iform species. For example, in species such erect (e.g. S. pinnatifolius var. alpinus). as S. quadridentatus and S. hispidulus the Some species are rhizomatous (having a taproot is considerably stouter than the rhizome, an underground stem, usually secondary roots, which are rather fine growing horizontally). Two species in and hardly fleshy. Conversely, in species the key have scrambling, twining or such as S. phelleus and S. hispidissimus, climbing stems, often forming extensive the taproot is slender and no stouter than tangled infestations (Delairea odorata and the secondary roots, which are distinctly S. angulatus). fleshy and generally unbranched except for occasional fine rootlets. Secondary roots Succulent: Thickened due to a high fluid of S. prenanthoides become particularly content. Plants may be both fleshy and fleshy and are characteristically slightly succulent or may be succulent only. In tuberiform (resembling a tuber, i.e. fleshy the latter case, leaves or stems will press and tapering at each end). quite thin.

Acknowledgments

Hans and Annie Wapstra made useful com­ and have appeared in his previous manuscripts ments on earlier versions of the manuscript, as cited in the references. Kim Hill extracted collected fresh specimens to test the key, and data records from the Tasmanian Herbarium. kindly allowed use of their excellent colour The anonymous referees commented on an photographs. All line drawings, except as earlier version of the manuscript. indicated in captions, are by Ian Thompson

References

Belcher RO (1996) Australian alpine scapose radiate Buchanan AM (2005) ‘A Census of the Vascular Plants taxa of Senecio (Asteraceae). Muelleria 9, 115–131. of Tasmania & Index to the Student’s Flora of Belcher RO, Albrecht DE (1994) Senecio psilocarpus Tasmania.’ Fourth Edition. (Tasmanian Herbarium, (Asteraceae), a new species of erechthitoid Senecio Tasmanian Museum and Art Gallery, Occasional from western Victoria and south-eastern South Publication No. 7: Hobart) Australia. Muelleria 8, 113–117. Curtis WM (1963) ‘The Student’s Flora of Tasmania Black JM (1928) Additions to the flora of South Part 2 Angiospermae: Lythraceae to Epacridaceae.’ Australia, No. 26. Transactions of the Royal Society of (Government Printer: Hobart) South Australia 52, 230. Lawrence ME (1980) Senecio L. (Asteraceae) in Bremer K (1994) ‘Asteraceae: Cladistics and Clas­ Australia: Chromosome numbers and the occur­ sification.’ (Timber Press: Portland: Oregon) rence of polyploidy. Australian Systematic Botany 13, 409–423.

92 An Illustrated and Annotated Key to the Tasmanian Species of Senecio KANUNNAH

Thomas DC (2004) Hybridisation between radiate and Thompson IR (2005) Taxonomic studies of Australian erechthitoid species of Senecio L. on Mount Macedon, Senecio (Asteraceae): 5. the S. pinnatifolius/S. lautus Victoria. The Victorian Naturalist 121(1), 23–31. complex. Muelleria 21, 23–76. Thompson IR (2004a) Taxonomic studies of Australian Thompson IR (2006) A taxonomic treatment of tribe Senecio (Asteraceae): 1. the disciform species. Senecioneae (Asteraceae) in Australia. Muelleria 24, Muelleria 19, 101–214. 51–110. Thompson IR (2004b) Taxonomic studies of Australian Walsh NG (1999) Senecio. In ‘Flora of Victoria Vol 4’. Senecio (Asteraceae): 2. the shrubby, discoid species (Eds NG Walsh, TJ Entwisle) pp. 941–965. (Inkata and the allied radiate species Senecio linearifolius. Press: Melbourne) Muelleria 20, 67–110. Wapstra H, Wapstra A, Wapstra M, Gilfedder L (2005) Thompson IR (2004c) Taxonomic studies of Australian ‘The Little Book of Common Names for Tasmanian Senecio (Asteraceae): 3. radiate, arid region species Plants.’ (Department of Primary Industries, Water allied to S. magnificus and the radiate, alpine species and Environment: Hobart) S. pectinatus. Muelleria 20, 111–138. Thompson I (2004d) A new name for Senecio glandulosus (Asteraceae). Muelleria 20, 139–140.

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