Styphelioideae

The Styphelioideae include 35 genera and some 420 species. They are found throughout the Australasian region but are the most diverse and abundant in south-west Western Australia, Tasmania and south-east Australia. Outliers extend the range to Tierra del Fuego (Lebetanthus), Hawaii (Styphelia) and south-east Asia (Leucopogon).
The monophyly of the Styphelioideae is very well supported, and the group is easily diagnosed. Morphological apomorphies for Styphelioideae include the lignified leaf epidermis (char. #21; Fig. 22), scarious inflorescence bracts (char. #38), persistent corolla (char. #48), stamens less than two times the number of corolla lobes (char. #51, Fig. 21), smooth filaments (char. #55), bisporangiate, usually monothecal anthers (char. #57), and probably a branched vascular bundle in the petiole or leaf base (char. #6). Only the presence of monothecal anthers is not homoplasious (Fig. 23). Epidermal leaf lignification is uncommon in Ericaceae (see Fig. 22), occurring outside Styphelioideae only in the Lyonieae. Anthers opening by longitudinal slits may also be synapomorphic. Core Styphelioideae, i.e., all genera except for Prionotes and Lebetanthus, have several additional synapomorphic features. These include parallel- (or more or less palmate-) veined leaves (char. #15) and a lack of multicellular hairs (char. #22). Epipetalous stamens (char. #52) has a single origin below Archerieae (Fig. 7). The stamens are free from the corolla in Andersonia, Lysinema, Richea, and Woollsia (Crayn et al., 1998) suggesting reversals of this character. For example, in Richea the corolla is deciduous, falling off at anthesis as a cap, precluding epipetaly. Outside Styphelioideae, only Diplarche (Rhodoreae) possesses truly epipetalous stamens. Traditionally (e.g., Brown, 1810; Bentham & Hooker, 1876), styphelioids have been divided into two subgroups, comprising the capsular-fruited and fleshy-fruited taxa. However, leaf and stem anatomical characters also have been used as the basis for the primary division in the group (Watson, 1967). More recently, Powell et al. (1996, 1997) conducted the first cladistic studies of the group and recognized four tribes, namely Richeeae (equivalent to Richeoideae sensu Watson, 1967), Cosmelieae, Styphelieae and Epacrideae, although the last appeared paraphyletic in their analysis. Parsimony analyses of nucleotide sequence data (Crayn et al., 1996; 1998; Crayn & Quinn, 2000) have supported the monophyly of some of these named groups but have clearly demonstrated others to be artificial. The results of the matK analysis in Kron et al., 2002, Bot. Rev. support the recognition of Prionoteae, Oligarrheneae, Richeaeae, Epacrideae, Styphelieae, and Cosmelieae as named clades (Crayn & Quinn, 1998). In some most parsimonious trees Archeria (i.e., Archerieae) branches after the Prionoteae but before the remaining styphelioids. However, this relationship is not supported in the strict consensus where Archeria, Oligarrheneae, and remaining styphelioids (except Prionoteae) form a trichotomy. Recent work using alternative DNA regions has given broad support to this classification (Crayn et al., 1998; Crayn & Quinn, 2000; Owens et al. in prep).

Styphelioideae

Styphelioideae Sweet, Fl. Australas.: ad t. 47. 1828 (as
Stypheliae). Type genus: Styphelia R.Br.

Epacridoideae Link, Handbuch 1: 601, 1829 (as Epacrideae).

Shrubs, small trees or climbers, evergreen, with alternate, mostly entire leaves; veins often ± palmate, parallel, or reduced to one. Leaf epidermal cells lignified. Bracts and bracteoles scarious. Inflorescence variable, axillary or terminal. Flowers 4-5-merous, actinomorphic. Calyx persistent; corolla persistent, sympetalous, usually tubular or campanulate, the lobes small to large. Stamens 2, 4 or 5, usually epipetalous; anthers bisporangiate, inverting early in development, mostly monothecal, dehiscing by longitudinal slits, lacking a fibrous endothocium and disintegration tissue. Pollen in monads, tetrads, or shed as reduced tetrads with one or more cells aborting, without viscin threads. Ovary 1-11-locular, with axile or apical placentation, superior; style impressed or not; stigma capitate or lobed. Fruit drupaceous or a loculicidal capsule; seeds with variable testa; embryo with 2 cotyledons.
[Characters in boldface are potential synapomorphies for the group based on the study by Kron et al., 2002, Botanical Review.]

Prionoteae

The taxonomic history of Prionotes (one species, P. cerinthifolia) and Lebethanthus (one species, L. myrsinites) exemplifies the power of cladistic analysis and the weakness of an overall similiarity approach to classification and evolutionary relationships. Stevens (1971) discussed the characteristics that led to these taxa being alternately placed in Epacridaceae or Ericaceae (as previously circumscribed). Based on the concepts of overall similarity these genera could not be satisfactorily placed in either group because they possessed a combination of characters of both “Ericaceae” and Epacridaceae. However, cladistic analysis shows that Prionotes and Lebetanthus possess many plesiomorphic characters with respect to the Styphelioideae (as here defined) while also possessing distinct synapomorphies of the group (such as a lignified leaf epidermis and monothecal anthers; Figs. 22 and 23, respectively). The sister relationship of Prionotes and Lebetanthus to remaining Styphelioideae was also found by Anderberg (1993) and is supported in this study in both the individual and combined molecular analyses (see also Crayn et al., 1998).

Prionoteae

Prionoteae Drude, in Engl. & Prantl, Nat. Pflanzenfam. IV(1): 72. 1889. – Type genus: Prionotes R. Br.

Straggling shrubs or climbers, leaves alternate, glabrous, margins with a few blunt teeth, a single stalked, glandular hair located in each sinus, leaf base narrow, veins pinnate-reticulate, having abaxial fiber cap contacting neither epidermis. Inflorescence axillary at the end of long branches, flowers solitary; bracts small, grading upwards to one or two larger bracteoles. Flowers 5-merous. Calyx lobes ciliolate; corolla sympetalous, cylindrical, somewhat constricted at the throat, the lobes small, blunt, recurved. Stamens 5, free, the filaments long, straight; anthers dithecal, located at the throat, lacking appendages. Pollen in tetrads. Ovary 5-locular, with axile placentation, several ovules in each cell, superior; style long, filiform, impressed. Fruit a loculicidal. [Lebetanthus Endl.; Prionotes R. Br.]

Archerieae
The Archerieae comprise the small genus Archeria (6 spp.) native to Tasmania and New Zealand. Powell et al. (1996) considered Archeria related to Epacris, but this relationship is not supported by the matK analysis or other molecular analyses of Crayn et al. (1998) and Crayn & Quinn (2000). Relationships of Archerieae to the remaining epacridoids are discussed in detail in Crayn and Quinn (1998). Both Prionotes and Archeria share the character of flowers with bracteoles in the middle of the pedicel. This characteristic is also common in Vaccinioideae, which is consistent with it being plesiomorphic in Styphelioideae.
Archerieae
Archerieae Crayn & Quinn, Aust. Syst. Bot. 11: 23, 1998. – Type genus: Archeria Hook. f.

Shrubs, with leaves small, alternate, glabrous, entire or serrulate, one to several longitudinal veins having abaxial fiber cap contacting neither epidermis. Flowers solitary or in short terminal racemes; bracts present, usually caducous; bracteoles small and paired. Flowers 5-merous. Calyx lobes ciliolate, persistent; corolla sympetalous, broadly cylindrical to campanulate, the lobes imbricate in bud, spreading or recurved. Stamens 5, epipetalous, the filaments short and straight; anthers monothecal, lacking appendages. Pollen in tetrads. Ovary 5-locular, deeply lobed, with axile to basal placentation, ovules numerous; style deeply impressed. Fruit a loculicidal capsule. There are no obvious morphological synapomorphies known for Archerieae.
Oligarrheneae
Although not included in the morphological analysis presented here, Oligarrhena and Needhamiella form a clade in the matK analysis that is sister to Richeeae, Epacrideae, Cosmelieae, and Styphelieae. This clade is supported by the potential synapomorphies of a two-locular ovary and a glabrous corolla tube (Crayn et al., 1998). Traditionally, Oligarrhena and Needhamiella have been considered closely related to the Styphelia group (see Crayn et al., 1998 for discussion), but this relationship is not supported by the matK analysis presented here or by other molecular analyses of the epacridoids (Crayn et al., 1998).
Oligarrheneae
Oligarrheneae Crayn & Quinn, trib. nov. – Type genus: Oligarrhena R. Br.
Latin diagnosis: Venae in transsectione folii fasciculis fibrarum epidermides ambo non contingentibus; flores 4- vel 5-meri staminibus 2 vel 4; ovarium biloculare ovulis in quoque loculo solitariis ad apicem affixis; stylus haud impressus; fructus drupaceus.

Shrubs, with leaves minute, appressed, alternate, entire, with narrow leaf base and one to several longitudinal veins with abaxial fiber cap contacting neither epidermis. Flowers in terminal compound racemes or blastotelic spikes; bracts present or absent; bracteoles 2. Flowers 4 or 5-merous. Calyx lobes ciliolate, persistent; corolla sympetalous, cylindrical, the lobes imbricate/valvate in bud, straight or spreading. Stamens 2 or 4, epipetalous; anthers monothecal, lacking appendages. Pollen in monads or shed as reduced tetrads with one or more cells aborting. Ovary 2-locular, with apical placentation, a single ovule in each cell; style very short, not impressed. Fruit a drupe. [Needhamiella Watson; Oligarrhena R. Br.]
Cosmelieae
This tribe comprises three genera, Andersonia, Cosmelia, and Sprengelia, and is strongly supported as a clade in the matK analysis presented here and in other molecular analyses (Crayn et al., 1998; Crayn & Quinn, 2000). Results of previous morphological studies (Powell et al., 1996) suggested that likely synapomorphies for Cosmelieae are the sheathing leaves that do not leave a scar and the unilacunar nodal anatomy. In the matK analysis (Fig. 4) Cosmelieae are sister to Styphelieae. This result differs from the rbcL analysis of Crayn et al. (1998) where Cosmelieae are sister to the Epacrideae + Styphelieae. However, parsimony jackknife support for the rbcL branching pattern (Crayn et al., 1998) is lacking.
Cosmelieae
Cosmelieae Crayn & Quinn, trib. nov. – Type genus: Cosmelia R. Br.
Latin diagnosis. Folia basibus caulem cingentibus sed folia cum cortice exuta cicatricibus itaque deficientibus; venae in transsectione folii fasciculis fibrarum epidermidem adaxialem basin versus contingentibus

Shrubs, with leaves alternate, glabrous; the leaf base sheathing the stem, the sheath and cortex falling with the leaf to leave a stem free of scars, the veins parallel with abaxial fiber cap that contacts the adaxial epidermis toward the leaf base; adaxial leaf stomata tetracytic; nodes unilacunar. Flowers solitary, axillary or terminal, often crowded into heads; bracts not scarious, persistent, one to many; bracteoles deciduous, more than 2. Flowers 5-merous. Calyx lobes persistent; corolla sympetalous, though sometimes petals almost free, cylindrical, sometimes conspicuously constricted at the throat, or spreading; the lobes imbricate to almost valvate in the bud. Stamens 5, epipetalous, or sometimes free and then filaments flat, strongly flexuose; anthers dithecal or monothecal, lacking appendages. Pollen in tetrads. Ovary 5-locular, with several ovules in each cell, placentation axile; style impressed. Fruit a loculicidal capsule.
Richeeae

In contrast to Cosmelieae, Richeeae possess sheathing leaves that leave a distinct annular scar and possess nodes that are tri- or multilacunar (Crayn et al., 1998; Powell et al., 1996). In the analysis of Powell et al. (1996) the sheathing leaf base was a synapomorphy linking Cosmelieae and Richeeae, but in Cosmelieae the stem cortex detaches with the abscissing leaf, leaving an unscarred stem, while in the Richeae the cortex remains. These differences may indicate that the states are not homologous in the two tribes.
Richeeae are strongly supported in the matK analysis presented here as well as in previous analyses using rbcL (Crayn et al., 1998). Three genera are recognized within Richeae: Dracophyllum, Richea, and Sphenotoma. In the matK tree (Fig. 4) Richeeae are sister to Cosmeliaeae + Styphelieae, but this relationship lacks parsimony jackknife support. The rbcL data (Crayn et al., 1998) indicate Richeeae as branching earlier in the history of Styphelioideae than the matK data presented in this study, but again without parsimony jackknife support. Because of this lack of support Richeeae are indicated as sedis mutabilis in the classification
(Fig. 1).

Richeeae
Richeeae Crayn & Quinn, trib. nov. – Type genus: Richea R. Br.
Latin diagnosis: Folia basibus caulem cingentibus cicatricibus annularibus remanentibus; venae in transsectione folii fasciculis fibrarum epidermides ambo contingentibus; nodi multilacunares.

Small trees with unbranched stems or much-branched shrubs, leaves alternate, glabrous, with a few blunt teeth; leaf base sheathing the stem and falling with the leaf to leave annular scars; the veins parallel, having both adaxial and abaxial fiber caps that extend as a flange to contact each epidermis or the lignified hypodermis; nodes multilacunar. Flowers solitary or in spikes, racemes or panicles; bracts persistent or deciduous; bracteoles 2, deciduous. Flowers 5-merous. Calyx lobes ciliate, persistent; corolla sympetalous, cylindrical, the lobes either fused to form a calyptra that splits transversely and falls at anthesis to leave a persistent basal ring, or lobes free and the corolla tube sometimes constricted at the throat. Stamens 5, free, or epipetalous, if free the filaments short, straight; anthers monothecal, lacking appendages. Pollen in tetrads. Ovary 5-locular, with axile placentation, several ovules in each cell; stigma small, capitate; style impressed. Fruit a loculicidal capsule.
Epacrideae
Epacrideae comprise five genera (Budawangia, Epacris, Lysinema, Rupicola, Woollsia). In the matK analysis (Fig. 4) they are represented only by Epacris, Lysinema, and Rupicola. This is a well supported clade in the rbcL analysis (Fig. 5) as well as the more comprehensive studies by Crayn et al., 1998). Generic relationships within this group have been studied by Powell et al. (1996) and Crayn et al. (1998), but require further investigation because preliminary results indicate that the recognition of Budawangia and Rupicola would result in a paraphyletic Epacris (Crayn et al., 1998).
Epacrideae
Epacrideae Dumort., Anal. Fam. Pl.: 28, 1829 (as Epacreae). – Type genus: Epacris Cav.
Epacridinae Kitt. in A. Rich., Nouv. Elém. Bot. ed. 3.,
Germ. transl.: 824. 1840 (as Epacreae)

Shrubs with leaves alternate, glabrous, sessile or shortly petiolate, the veins palmate or reduced to one, with abaxial fiber cap contacting neither epidermis. Flowers solitary, axillary; bracts numerous, persistent, bracteoles more than 2. Flowers 5-merous. Calyx lobes ciliate, persistent; corolla sympetalous, cylindrical, the lobes imbricate in the bud, then spreading. Stamens 5, epipetalous or sometimes free; anthers monothecal, lacking appendages. Pollen in tetrads. Ovary 5-locular, with several ovules in each cell; placentation axile; style impressed. Fruit a loculicidal capsule.

Styphelieae
The Styphelieae, which are characterized by fleshy fruit, have the broadest distribution of the epacridoid tribes, being found in all parts of the range of the subfamily except for South America. It is also the largest tribe with 20 currently recognized genera and at least 320 species (Powell et al., 1987; Weiller, 1996a, b). Although some genera show east-west Australian disjunctions, viz., Acrotriche, Astroloma, Brachyloma, Leucopogon, Monotoca and Styphelia, several of these genera are likely not monophyletic (Powell et al., 1997). Relationships within Styphelieae are complex. Recent morphological (Powell et al., 1997) and molecular studies (Taaffe, et al., in press) indicate that Leucopogon as traditionally defined is polyphyletic but details of the relationships have yet to be resolved (Taaffe, et al., in press). As a clade, Styphelieae are stongly supported as monophyletic (Figs 4, 5, 6). Previous morphological studies have indicated that Styphelieae have the following synapomorphies: fruit drupaceous, ovary 1-11 locular (each locule containing a single ovule), and the corolla mostly hairy inside (Taaffe, et al., in press). The fleshy fruits of Styphelieae are homoplasious as this character has evolved several times within Ericaceae (e.g., Arbutoideae, Empetreae, and Vaccinieae).
Styphelieae
Styphelieae Bartl., Ord. Nat. Pl.: 158, 1830. – Type genus: Styphelia R.Br.
Stenanthereae Dumort., Anal. Fam. Pl.: 28. 1829.
Stypheliinae Kitt. in A. Rich., Nouv. Elem. Bot., ed. 3,
Germ. transl.: 824. 1840 (as Styphelieae).

Shrubs, with leaves alternate, entire, with leaf base narrow and one to several longitudinal veins having abaxial fiber cap that contacts the abaxial epidermis. Flowers in terminal or reduced axillary racemes; bracts several grading upwards in size, or one, mostly small and persistent, sometimes leaf-like and caducous; bracteoles 2. Flowers 5-merous. Calyx lobes ciliate, persistent; corolla sympetalous, cylindrical, the lobes straight, spreading or recurved, mostly valvate in bud, occasionally imbricate. Stamens 5, epipetalous; anthers monothecal, with or without appendages. Pollen in monads, sometimes in tetrads or shed as reduced tetrads with one or more cells aborting. Ovary 2-11-locular, each with a single ovule, placentation apical, style not impressed. Fruit drupaceous and brightly colored, sometimes splitting to release endocarp, which sometimes splits into separate pyrenes.

Key to Styphelioideae
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