"Isachneae ms." (Cyrtococcum, Isachne, Coelachne) July 2010

ISACHNEAE

B.K.Simon, C.M.Weiller & R.D.Webster

Isachneae, Benth., J. Linn.Soc.Bot.19: 30 (1881)

This tribe was erected to accommodate a number of genera of grasses having an affinity with the panicoids, but traditionally kept separate on the basis of a few morphological features that include a well developed rachilla between the glumes and between the florets, the two florets which are much more similar to each other than in the true panicoids (in most species of Isachneae both are fertile), and the spikelet usually breaking up above the glumes.  Whether these morphogical characters indicate that the tribe is monophyletic has yet to be demonstrated, but definitive evidence will come from molecular data. Recent evidence (Sanchez-Ken 2003) points to a closer relationship with Eriachne  and Micraira, than to the panicoids.

C.E.Hubbard, Hooker's. Icon. Pl. 35: t.3440:3-4 (1943); R.D. Webster, The Australian Paniceae (Poaceae) 102 (1987).

KEY TO GENERA 

1   Spikelets falling with the glumes; upper glume 3 nerved

 CYRTOCOCCUM

1:  Spikelets disarticulating above the glumes; upper glume with 5 or more nerves

2   Upper lemma indurate

ISACHNE

2:  Upper lemma hyaline to membranous

COELACHNE

COELACHNE

Coelachne R. Br., Prodr. 187 (1810); from the Greek koilos (hollow) and achne (chaff, scale), referring to a ventricose lower lemma.

Type: C. pulchella R. Br.

Flowering culms caespitose or decumbent, herbaceous; nodes hairy (pubescent) or glabrous. Leaf blades flat. Plants bisexual, with hermaphrodite florets. Inflorescence a panicle (rarely reduced to a raceme), exserted at maturity. Spikelets with disarticulation above the glumes, terete to dorsally compressed, ovate. Glumes 2, ± equal or very unequal, shorter than the adjacent lemmas, rounded on the back; lower glume ovate, glabrous; upper glume oblong, 5–7 nerved, glabrous, muticous. Lower floret bisexual; lemma membranous to chartaceous, with apex acute to rounded; palea acute. Upper floret female, shorter than the lower floret; lemma white, decidedly firmer than glumes, hyaline to membranous, smooth, oblong; palea hyaline to membranous, smooth (hairy with strigose hairs). Lodicules developed (fleshy). Hilum short.

A genus of about 10 species in tropical Australia, Asia and Africa; 1 endemic to Australia.

C.E. Hubbard, Coelachne pulchella R.Br. Hooker's. Icon. Pl. 35: t.3440:1–3 (1943); R.D. Webster, Coelachne in The Australian Paniceae (Poaceae) 33–34 (1987).

Coelachne pulchella R. Br., Prodr. 187 (1810)

T: Paspalum pulchellum (R.Br.) Raspail, Ann. Sci. Nat. (Paris) 5: 301 (1825). T: Endeavour R, Qld, J. Banks & D. Solander; holo: BM, n.v. (photo BRI); iso BRI.

Illustrations: D.Sharp & B.K.Simon, AusGrass (2002).

Annual, stoloniferous. Flowering culms 7–20 cm tall, 4–8 noded. Internodes longer than the associated leaf sheaths or shorter than the associated leaf sheaths. Ligule a fringe of hairs (hairs sparse, usually only with a few scattered strigose hairs). Leaf blades 1–3 cm long, 2–5 mm wide. Inflorescence 2–13 cm long. Primary branches 0.7–1.5 cm long. Spikelets 3–10 on a typical lowermost primary branch, 1.3–1.8 mm long, 0.7–1 mm wide; lower glume 0.7–1 mm long, 3 nerved (obscure); upper glume 1–1.3 mm long, ovate or elliptic or obovate. Lower floret; lemma 1.2–1.5 mm long, 0.4–0.5 mm wide. Upper floret; lemma 0.7–1 mm long. Anthers 0.3–0.4 mm long. Fig xx (ABRS - Enid Mayfield).

Native; Rare in tropical N.T. and Qld. Tropical and subtropical sub-humid woodlands. Flowering July to Aug. Map 925.

N.T.: Groote Eylandt, C.R.Dunlop 2951 (BRI, NT); nr Alligator Pt, S.T.Blake 16666 (AD, BRI, CANB, NSW, PERTH). Qld: 4–5 ml [6–8 km] N of Mossman, S.T.Blake 15006 (BRI, CANB, DNA, K, MEL, NSW) Brown's Ck, Pascoe R., L.J.Brass 19639 (BRI, CANB); Vyces Crossing on Weipa-Mapoon rd, J.R.Clarkson 4891 (BRI, CANB, DNA, K, L, MO, NSW, PERTH, QRS).

Inflorescence shape and spikelet shape distinguish it from other members of the genus.


ISACHNE

Isachne R. Br., Prodr. 196 (1810); from the Greek isos (equal) and achne (chaff), referring to two equal florets, or equal glumes, or glumes equalling lemmas, or all these in combination (?).

Type: I. australis R. Br. ( = I. globosa (Thunb.) O.Kuntz).

Annual or perennial, rhizomatous (rarely and often aquatic), stoloniferous. Flowering culms decumbent; nodes hairy (pubescent) or glabrous. Internodes longer than the associated leaf sheaths. Ligule a fringe of hairs or absent. Leaf blades flat. Plants bisexual, with hermaphrodite florets (in some species). Inflorescence a panicle, exserted at maturity. Spikelets with disarticulation at the base of the spikelet, 2 flowered, terete or dorsally compressed, ovate to obovate. Glumes 2, ± equal, long relative to the adjacent lemmas, rounded on the back; lower glume ovate to obovate, hairy or glabrous, strigose; upper glume elliptic, hairy or glabrous or scabrous, strigose, muticous. Lower floret male, or bisexual; lemma 3 nerved or 5 nerved, puberulent (to papillate), with apex acute to truncate; palea with a rounded apex. Upper floret bisexual or female, subequal to or shorter than the lower floret; lemma 5–7 nerved, white to yellow, indurate, smooth or muricate, elliptic to obovate; palea indurate, smooth or muricate. Hilum long-linear.

About  95 species native to the tropics with many in Asia;  4 species in Australia, all  native, although  1 is thought to be introduced. Diagnostic features of Isachne included the elongated pedicels, indurate upper lemma and palea  and the similarity of the florets.

R.D. Webster, Isachne in The Australian Paniceae (Poaceae) 101–104 (1987); J.S. Vickery, Isachne in Flora of New South Wales, No. 19 Gramineae 221–223 (1975); E.A.P. Iskandar and J.F. Veldkamp, A revision of Malesian Isachne sect. Isachne (Gramineae, Panicoideae, Isachneae), Reinwardtia 12: 159-179 (2004)


1   Spikelets 1.5-3 mm long

     Glumes glabrous and rounded at apex

3. I. globosa

     2: Glumes covered with bristles and pointed

        at apex

 

4. I. sharpii

1: Spikelets less than 1.5 mm long

     3 Upper glume hairy; upper lemma glabrous; perennial

1. I. confusa

     3: Upper glume glabrous; upper lemma hairy; annual

2. I.  minutula

1. Isachne confusa Ohwi, Bull. Tokyo Sci. Mus. 18: 14 (1947)

T: Sumatra, H.A.B.Bünnemeijer, 18 Oct 1917, 1577; holo: BO, n.v.: iso: L, n.v. photo BRI).

[Isachne rigida auct. non Nees ex Miq.].

Illustrations: E.E.Henty, Man. Grasses New Guinea 119, pl. 45a (1969); K.Domin, Biblioth. Bot. 85: 292 (1915) as Isachne rigida; D.Sharp & B.K.Simon, AusGrass (2002).

Perennial (the base becoming hardened). Flowering culms 10–40 cm tall, 8–15 noded. Ligule absent. Leaf blades 0.7–2.5 cm long, 2–10 mm wide. Inflorescence 1–4 cm long. Primary branches 0.5–1.5 cm long. Spikelets 2–5 on a typical lowermost primary branch, with the upper floret fertile, terete, 1–1.2 mm long, 0.8–0.9 mm wide; lower glume 0.9–1.1 mm long, elliptic, 5 nerved, hairy, strigose; upper glume 0.85–1.1 mm long, elliptic, 5 nerved (-7), hairy, strigose. Lower floret male; lemma 0.9–1.1 mm long, 0.8–0.9 mm wide, indurate, 5 nerved, with apex rounded. Upper floret female subequal to or shorter than the lower floret; lemma 0.7–1 mm long, yellow, muricate; palea muricate. Anthers 0.5–0.7 mm long.

Native; tropical Asia (Burma and Malesia to the Carolines) and Australia, where it occurs in tropical N.T. and Qld. Tropical and subtropical sub-humid woodlands and coastal grasslands. Flowering May to Oct. Map 921.

N.T.: Melville Is., C.R.Dunlop 3447 (BRI, NT); Yirrkala, R.L.Specht 977 (BRI, MEL); 74 miles [119 km] W of Oenpelli Mission, P.K.Latz 3042 (AD, BRI). Qld: 20 km NNW of Ingham and 4 km E of Bruce Hwy, M.Lazarides 8116 (BRI, CANB).

2. Isachne minutula (Gaudich.) Kunth, Rév. Gram.: 2: 407, t.117 (1831)Panicum minutulum Gaudich., Freyc., Voy. Uranie 410 (1829); Isachne miliacea Roth var. minutula (Gaudich.) Fossberg & Sachet, Micronesica 18: 55 (1984). T: Marianas Is., Gaudichaud s.n. holo : P, n.v.


[Isachne pulchella auct. non Roth in Roem. & Schult.]

[Isachne myosotis auct. non Nees]

Illustrations: F.M.Bailey, Compr. Cat. Queensland Pl. 608, fig. 585 (1913), as I. myosotis Nees; D.Sharp & B.K.Simon, AusGrass (2002) as I.pulchella.

Annual. Flowering culms 3–35 cm tall, 2–5 noded. Ligule a fringe of hairs, 0.8–1.2 mm long. Leaf blades 2–5 cm long, 2–8 mm wide. Inflorescence 2–12 cm long. Primary branches 0.6–5 cm long. Spikelets 4–14 on a typical lowermost primary branch, with the upper floret fertile, dorsally compressed, 1–1.6 mm long, 0.7–0.9 mm wide; lower glume elliptic, 1–1.6 mm long, 5–7 nerved, glabrous; upper glume 1.1–1.5 mm long, elliptic to obovate, 5–7 nerved, glabrous or scabrous. Lower floret male; lemma 1–1.5 mm long, 0.7–0.9 mm wide, chartaceous, 3 nerved, with apex acute to rounded. Upper floret bisexual subequal to the lower floret; lemma 1–1.3 mm long, white, smooth; palea smooth. Anthers 0.8–0.9 mm long.

Native, or introduced; from tropical Asia to Australia, where some authorities consider it introduced. Tropical and subtropical rain forests, tropical and subtropical sub-humid woodlands, and coastal grasslands. Flowering Mar. to July. Map 922.

W.A.: Kimbolton Hsd,  A.A.Mitchell 3093 (BRI, PERTH). N.T.: 10.8 km ESE of Nourlangie Ranger Stn. on Pine Creek Rd., M.Lazarides 8815 (BRI, CANB); Elcho Is., P.K.Latz 6277 (BRI, DNA). Qld: Freshwater, near Cairns, S.T.Blake 14977 (BRI, CANB, NSW); S.T.Blake 9692 (BRI, CANB, K, MEL, MO, NSW, PERTH).

Occurs in damp shaded forests and swampy areas.

3. Isachne globosa (Thunb.) O. Kuntz, Révis. Gen. Pl. 2: 778 (1891)

Milium globosum Thunb., Fl. Jap. 49 (1784). T: without specific locality, Japan, Thunberg 2041: holo: UPS, n.v., fide TROPICOS. microfiche IDC 1036

Isachne australis R.Br., Prodr. 196 (1810); Panicum antipodum Spreng., Syst. Veg. 1: 314 (1824); Panicum australe (R.Br.) Raspail, Ann. Sci. Nat. (Paris) 5: 299 (1825), nom. illeg. non Spreng. (1824). T: SE of Sydney [Port Jackson], N.S.W.; R.Brown Iter Australiense 6129; holo: BM (photo BRI), US, fragm.

Panicum antipodum Spreng., Syst. Veg. 1: 314 (1824), nom. illeg. T: Nov. Holl. [Australia], n.v..


Illustrations: T.D.Stanley in T.D.Stanley & E.M.Ross, Fl. SE Queensland 3: 248, fig. 38H (1989); S.W.L.Jacobs & C.A.Wall in G.J.Harden (ed.), Fl. New South Wales 4: 493 (1993); N.G.Walsh in N.G.Walsh & T.J.Entwisle (eds), Fl. Victoria 2: 617, fig. 124h-i (1994).

Annual or perennial. Flowering culms 25–60 cm tall, 4–8 noded. Ligule a fringe of hairs, 1–2 mm long. Leaf blades 4–14 cm long, 3–9 mm wide. Inflorescence 6–12 cm long. Primary branches 2–5 cm long. Spikelets 4–14 on a typical lowermost primary branch, with the upper floret fertile, terete or dorsally compressed, 1.8–2.4 mm long, 1–1.2 mm wide; lower glume obovate or elliptic, 1.5–2.2 mm long, 7 nerved, glabrous; upper glume 1.4–2.1 mm long, elliptic, 9 nerved, glabrous. Lower floret bisexual; lemma 1.5–2.2 mm long, 1–1.2 mm wide, cartilaginous, 5 nerved, with apex rounded. Upper floret female, shorter than the lower floret; lemma 1.4–1.8 mm long, white, muricate (but obscure); palea muricate. Anthers 1.4–1.6 mm long. Swamp Millet.

Native; from tropical Asia to Australia, where it occurs in tropical and temperate areas, except W.A. and Tas.; also in Japan and New Zealand. Tropical and subtropical wet sclerophyll forests, temperate wet sclerophyll forests, dry sclerophyll forests, tropical and subtropical sub-humid woodlands, temperate sub-humid woodlands, and coastal grasslands. Flowering throughout the year. Map 923.

N.T.: Quins Ck, Port Keats, C.S.Robinson (NT). S.A.: Mt. Lofty Ra., A.G.Spooner 1769 (AD). Qld: Innisfail, S.T.Blake 14466 (BRI). N.S.W.: Gara R., E of Armidale, R.Roe A82 (CANB). Vic: Goram Falls, N.G.Walsh 1522 (BRI, CANB, CHR, HO, MEL).

Diagnostic features include leaf length and shape, and the cartilaginous lower floret. Anatomically there appears to be a split between the northerly and southerly specimens. Those from Qld. and NT are broader and abaxially flat in transverse section; prickles are usually only present on the intercostal zones of the abaxial epidermis. Regarded as a good fodder species.

A semi-aquatic rapidly growing and highly palatable  grass.

4. Isachne sharpii B.K. Simon Austrobaileya 9: 207 (2010)

T: Palm Rd, Cape Tribulation, 21 Apr 2001, D.Sharp 293 holo: BRI; iso: CANB, K, L, MO, NSW.

Illustrations: D.Sharp & B.K.Simon, AusGrass (2002) as Isachne sp. A.

Annual. Flowering culms 26–44 cm tall, 5–10 noded. Ligule a fringe of hairs, 1.5–1.7 mm long. Leaf blades 2.5–5.5 cm long, 7–13 mm wide. Inflorescence 3.5–4 cm long. Primary branches 1–1.4 cm long. Spikelets 3–7 on a typical lowermost primary branch, with both florets fertile (?), dorsally compressed, elliptic, 2.5–2.8 mm long, 1.2–1.5 mm wide; lower glume ovate, 2.5–2.8 mm long, 9 nerved, hairy, setose; upper glume 2.5–2.8 mm long, ovate, 9–10 nerved, hairy. Lower floret bisexual; lemma c.2 mm long, c.1.5 mm wide, cartilaginous to indurate, smooth, 5 nerved, with apex rounded; palea c.1.8 mm long, c.1.3 mm wide, cartilaginous to indurate; anthers 3, pale, to 1.5 mm long; caryopsis to 1.2 x 0.8 mm, finely muricate, reddish. Upper floret bisexual, subequal to the lower floret; lemma c.2 mm long, c.1.5 mm wide, cartilaginous to indurate, smooth, 5 nerved ; palea c.1.8 mm long, c.1.3 mm wide, cartilaginous to indurate ; anthers 3, pale, to 1.5 mm long. . Fig xx.

Endemic; Daintree Forest, Cook District. Tropical and subtropical rain forests. Flowering Dec. and May. Map 924.

Qld: Palm Rd, Cape Trbulation, Licuala palm swamp, R.L.Jago 4560,  R.L.Jago 5978 (BRI); B.Gray & D.L.Jones 08188 (BRI, QRS); B.K.Simon 4330 & R.L.Jago (BRI, K, US)

Differs from I. globosa by the glumes being covered with bristles and pointed at the apex, as opposed to glabrous and rounded at the apex and by both florets being fertile.


CYRTOCOCCUM

Cyrtococcum Stapf, D.Prain, Fl. Trop. Afr. 9: 15 (1917), 9: 745 (1920); from the Greek kurtos (curved, crooked) and kokkos (a fruit), alluding to the gibbous spikelets.

Type: C. setigerum (P.Beauv.) Stapf = C. chaetophoron (Roem. & Schult.) Dandy.

Annual or perennial, sometimes stoloniferous. Flowering culms decumbent; nodes hairy or glabrous. Internodes longer than the associated leaf sheaths. Ligule membranous. Leaf blades flat. Plants bisexual, with hermaphrodite florets. Inflorescence exserted at maturity. Spikelets with disarticulation at the base of the spikelet, laterally compressed, elliptic or obovate or oblong. Glumes 2, unequal or very unequal, shorter than the adjacent lemmas, distinctly keeled or rounded on the back; lower glume lanceolate, 3 nerved, hairy or glabrous; upper glume oblong or obovate, 3 nerved, hairy or glabrous, villous to strigose, mucronate. Lower floret sterile (sometimes); lemma membranous, 5 nerved, indumentum shorter than the spikelet, villous to strigose, with apex acute or rounded. Upper floret, shorter or longer than the lower floret; lemma white, cartilaginous, smooth, oblong to elliptic (planoconvex in lateral view but oblong to elliptic in dorsal view), with an apical crest; palea chartaceous to indurate, smooth to irregularily striate. Hilum short.

A genus of 12 species native to the Old World tropics, including 2 native in the tropics of north Qld. C. deltoideum (Hack.) A.Camus has been introduced into Australia but has not become established. Diagnostic features include the lateral compression of the spikelets, a crested apex on the upper lemma and the gibbose upper glume and upper lemma (Webster, 1987).

O. Stapf, Cyrtococcum trigonum Stapf, Hooker's Icon.Pl. 31: t.3096: 1–3 (1922); B.K.Simon, Studies in Australian grasses 5. New species and new combinations of Queensland panicoid genera, Austrobaileya 3: 585–607 (1992); R.D. Webster, Cyrtococcum in The Australian Paniceae (Poaceae) 34–35 (1987).

Add C. patens  & C. accrescens

Spikelets glabrous

1. C. oxyphyllum

Spikelets with tubercle-based hairs

2. C. capitis-york

=                                                                                                                                                    =C. patens?

1. Cyrtococcum oxyphyllum (Steud.) Stapf, Hooker's Icon. Pl. 31: t. 3096 (1922), in obs.

Panicum oxyphyllum Hochst. ex Steud., Syn. Pl. Glumac. 1: 65 (1854). T: India, (Hrbr. Hohenock. Ind. or. nr. 627) Prvinc. Canara; n.v..

Panicum hermaphroditum Steud., Syn. Pl. Glumac. 1: 67 (1854). T: Philippines: Cuming 554. holo: P, n.v.; iso: BRI.

Illustrations: D.Sharp & B.K.Simon, AusGrass (2002).

Annual, stoloniferous. Flowering culms decumbent, 15–60 cm tall, 4–11 noded; nodes hairy or glabrous. Ligule 1–1.7 mm long. Leaf blades 6–14 cm long, 5–15 mm wide. Inflorescence 6–10 cm long. Primary branches 2–4 cm long. Spikelets 40–60 on a typical lowermost primary branch, elliptic to obovate (planoconvex), 1.6–1.9 mm long, 1–1.2 mm wide. Glumes unequal, distinctly keeled; lower glume not fused with the callus, ) 1–1.5 mm long (ca. 0.65 the length of the spikelet), lanceolate, glabrous; upper glume 1.3–1.7 mm long, oblong, glabrous. Lower floret; lemma 1.4–1.7 mm long, 0.55–0.65 mm wide, with apex rounded. Upper floret, subequal or longer than the lower floret; lemma 1.4–1.7 mm long, oblong to elliptic (planoconvex in lateral view but oblong to elliptic in dorsal view), with an apical crest; palea cartilaginous to indurate, smooth. Anthers 0.75–0.9 mm long.

Native; from the wet tropics of Asia to N coastal Qld. Temperate heaths (Rainforests (tropical and subtropical)), or alpine heaths (Sub-humid woodlands (tropical and subtropical)). Flowering Apr. to Sep. Map 926.

Qld: Lyons Lookout, B.K.Simon 2675 (BRI); near Cardwell, S.T.Blake 9715 (BRI); Iron Ra., L.J.Brass 19289 (CANB); Mulgrave, B.Hyland 7241 (CANB); upper Goldsborough, A.W.Dockrill 97 (QRS).

Relatively short pedicels, long leaves and glabrous spikelets characterise this species. In damp, shady ,forest habitats.

2. Cyrtococcum capitis-york B.K. Simon, Austrobaileya 3: 592 (1992)  (? = C. patens)

T: 10.8 km S of Batavia Downs, Qld, 21 Apr.1990, J.R.Clarkson 8477 & V.J.Neldner; holo: BRI; iso: B, BRI, DNA, NSW.

Perennial. Flowering culms 15–30 cm tall, 7–9 noded. Ligule 0.4 mm long. Leaf blades 2.5–7 cm long, 3–5 mm wide. Inflorescence 2–8 cm long. Primary branches 0.4 cm long. Spikelets 10 on a typical lowermost primary branch, obovate (obliquely), 1.5–1.8 mm long, 0.8–1 mm wide. Glumes very unequal, rounded on the back; lower glume 0.6–0.8 mm long, not fused with the callus, triangular or ovate, hairy (with tubercle-based hairs), setose (hairs tubercle-based); upper glume 1.5 mm long, obovate, hairy (with tubercle-based hairs). Lower floret;  lemma with apex acute. Upper floret shorter than the lower floret; lemma cartilaginous (softly), elliptic (saccate);. palea indurate (softly), smooth. Anthers 1 mm long. Fig xx (B.K.Simon Austrobaileya 3: 593 (1992).

Endemic; Cape York Peninsula, Qld. Flowering Apr. to June. Map 927.

Qld: Lankelly Ck, McIlraith Ra, P.I.Forster 10355 & M.C.Tucker (BRI); Cape Melville N.P., J.P.Stanton 1371 (BRI).

Close to C. deccanense from India and Sri Lanka, but has slightly smaller spikelets with tubercle based hairs.

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith