Homoranthus tricolor (Myrtaceae), a new 
species from south-eastern Queensland 
A.R. Bean 
Summary 
Bean, A.R. (2009). Homoranthus tricolor (Myrtaceae), a new species from south-eastern Queensland. 
Austrobaileya 8(1): 77-79. A new species of Homoranthus is described, illustrated and diagnosed 
against related species. It is of very restricted distribution near Mundubbera in south-eastern 
Queensland. 
Key Words: Homoranthus tricolor , Myrtaceae, taxonomy, Queensland flora 
A.R. Bean, Queensland Herbarium, Department of Environment & Resource Management, Brisbane 
Botanic Gardens, Mt Coot-tha Road, Toowong 4066, Queensland, Australia. Email: tony.bean@ 
derm.qld.gov.au 
Introduction 
In September 2007, Trevor Ritchie (DERM, 
Maryborough) discovered an unusual 
Homoranthus. Photographs and specimens 
were sent to the Queensland Herbarium. 
The material could not be matched with any 
existing specimens, nor would it key to any 
species in Craven and Jones (1991). It did not 
match either of the two species described 
by Hunter (1998), and while very similar 
to H. coracinus in floral characters (Bean 
2000), it could be easily distinguished from 
that species on leaf morphology. This new 
species is described as new, under the name 
H. tricolor. 
Homoranthus tricolor A.R.Bean species nova 
ab omnibus aliis speciebus Homoranthi floribus 
pendulis saepe solitariis, bracteolis grandibus 
praecipue viridibus persistentibus, hypanthio 
rubro cylindrico, sepalis nigris laciniatis et 
petalis praecipue nigris sed ad extremum 
distale viridibus distincta. Typus: Queensland. 
Burnett District: near junction of Delubra and 
Cadarga Creeks, 35 km SW of Mundubbera, 19 
September 2008, A.R.Bean 27986 & T.Ritchie 
(holo: BRI (1 sheet + spirit); iso: AD, CANB, 
MEL, NSW, US, distribuendi). 
Erect spreading shrub to 1.4 m high and 1 m 
wide. Bark grey, fibrous, slightly furrowed 
towards base of older plants. Leaves linear to 
narrowly oblanceolate, 5.3-7.2 mm long, 0.6- 
0.9 mm wide, green to grey-green, oil glands 
scattered and readily visible, apex acute to 
mucronulate; margins entire, not recurved 
in fresh material, but strongly recurved in 
dried material. Petioles 0.5-0.7 mm long. 
Inflorescence borne in upper leaf axils, 1 or 2 
flowered. Bracteoles cymbiform, not keeled, 
6-7 mm long, 5.3-5.8 mm wide, gland-dotted, 
mainly green but with white or red margins, 
apex obtuse, persistent at least until anthesis, 
enclosing base of hypanthium. Pedicels 
absent; peduncles 2.2-3.5 mm long. Flowers 
pendulous; hypanthium glabrous, 5-angled 
basally, otherwise cylindrical, 6-6.5 mm long, 
5-5.5 mm wide, papillose to ruminate and 
pale green basally, smooth and red distally. 
Sepals 5, each 5-6 mm long, 1.2-1.5 mm 
wide, black, entire and slightly tapering in 
basal half, and with 3-5 black laciniate lobes 
distally. Petals elliptical, concavo-convex, 
adnate to the distal part of the hypanthium, 
47-5.2 x 2.8-3.2 mm, dark purple to black 
basally and medially, apex and margins pale 
green, apex obtuse, margins entire. Stamens 
10, alternating with staminodes; filaments 
0.5-0.8 mm long, anthers globose, basifixed, 
dehiscing by pores. Style 18-20 mm long, 
straight or distally curved, creamy white, 
glabrous except for some simple spreading 
eglandular hairs below the stigmatic area. 
Ovules 10-12, collateral in two longitudinal 
rows. Fruits not seen. Fig. 1 
Accepted for publication 30 June 2009 
