Close scrutiny of Goodenia (Goodeniaceae) and allied genera in the ‘Core Goodeniaceae’ over recent years has clarified our understanding of this captivating group. While expanded sampling, sequencing of multiple regions, and a genome skimming reinforced backbone clearly supported Goodenia s.l. as monophyletic and distinct from Scaevola and Coopernookia, there appears to be no synapomorphic characters that uniquely characterise this morphologically diverse clade. Within Goodenia s.l., there is strong support from nuclear, chloroplast and mitochondrial data for three major clades (Goodenia Clades A, B and C) and various subclades, which lead to earlier suggestions for the possible recognition of these as distinct genera. Through ongoing work, it has become evident that this is impractical, as conflict remains within the most recently diverged Clade C, likely due to recent radiation and incomplete lineage sorting. In light of this, it is proposed that a combination of morphological characters is used to circumscribe an expanded Goodenia that now includes Velleia, Verreauxia, Selliera and Pentaptilon, and an updated infrageneric classification is proposed to accommodate monophyletic subclades. A total of twenty-five new combinations, three reinstatements, and seven new names are published herein including Goodenia subg. Monochila sect. Monochila subsect. Infracta K.A.Sheph. subsect. nov. Also, a type is designated for Goodenia subg. Porphyranthus sect. Ebracteolatae (K.Krause) K.A.Sheph. comb. et stat. nov., and lectotypes or secondstep lectotypes are designated for a further three names.

Goodenia, Goodeniaceae, nomenclature, phylogeny, taxonomy, Velleia

Representatives of the predominantly Australian family Goodeniaceae R.Br, a close relative to the cosmopolitan Asteraceae Bercht. & J.Presl (Tank and Donoghue 2010), have been the focus of various studies in recent years. The first molecular phylogeny of generic exemplars by Gustafsson et al. (1996) indicated that the monotypic and closely allied Brunoniaceae Dumort. was, in fact, embedded within Goodeniaceae. This was previously hypothesised by Carolin (1992a), due to the shared presence of a unique cup-like pollen presenter positioned at the apex of the style referred to as an indusium (Carolin 1960). Howarth et al. (2003) (and later expanded in Jabaily et al. 2014), studied the origin of Hawaiian species of Scaevola L., the only genus in the family with significant diversity outside of Australia (see table 1 in Jabaily et al. 2012). These studies confirmed that Scaevola dispersed from Australia into the islands of the Pacific at least four times, starting in the late Miocene and continuing into the Pliocene, and that homoploid hybridisation subsequently contributed to the extant diversity apparent across the islands today (Howarth and Baum 2005).

Our team completed the first comprehensive phylogeny of the family utilising cpDNA from 212 (out of 400+) species across 12 genera (Jabaily et al. 2012). Two major clades were identified within the family, the smaller of the two being the LAD clade composed of Lechenaultia R.Br., Anthotium R.Br., and Dampiera R.Br. with the remaining nine genera falling in the larger ‘Core Goodeniaceae’ clade (Fig. 1). Within the Core Goodeniaceae the monotypic Brunonia australis Sm. ex R.Br. placed sister to two large clades comprising Scaevola s.l. and Goodenia Sm. s.l., respectively. Generic-level taxonomic problems were noted in both clades. Firstly, the monotypic Diaspasis filifolia R.Br. was shown to be embedded within Scaevola while Goodenia s.l. (represented by a subset of 60 species), resolved into three major clades (denoted A, B, C), and was rendered paraphyletic due to the inclusion of Coopernookia Carolin, Selliera Cav. (Fig. 2I), Velleia Sm. (Fig. 2E), Verreauxia Benth., Scaevola collaris F.Muell. (Fig. 2B) and the monotypic Pentaptilon E.Pritz. This phylogeny was built using 3117 base-pairs of cpDNA including trnL-F and matK, and while phylogenetic support values were high for many smaller clades, the backbone topology of Goodenia s.l. was weakly supported in most analyses. A few subgeneric taxonomic groupings were largely monophyletic (e.g. subg. Monochila (G.Don) Carolin, subg. Goodenia subsect. Ebracteolatae K.Krause), but many were not (e.g. subg. Goodenia subsect. Goodenia and subsect. Coeruleae (Benth.) Carolin). Furthermore, other subgeneric groupings were not included or placed (e.g. sect. Porphyranthus G.Don, sect. Amphichila DC., and ser. Calogyne (R.Br.) Carolin of subg. Goodenia).

Figure 1. 

Summary of broad relationships in Goodeniaceae from Jabaily et al. (2012) based on a 50% majority-rule cladogram from a partitioned Bayesian inference analysis of trnL-F and matK, with additional bootstrap values from separate parsimony and maximum likelihood analyses (values above branches are Bayesian posterior probabilities, values below branches are maximum likelihood bootstrap). Left inset – Coopernookia strophiolata showing the unique indusium pollen presenter (red arrow) that is diagnostic for the family. Voucher: K.R. Thiele 3710. Image: K.R. Thiele.

Figure 2. 

Diagnostic features of various species in Goodenia s.l. A the type species Goodenia ovata B Scaevola collaris fan-like flowers and immature fleshy fruit C G. concinna subumbellate inflorescence D G. scapigera with short, stiff hairs on the style, narrow indusium and white fan-like flowers E Velleia cycnopotamica with free sepals attached below the ovary (white arrow) F G. vilmoriniae seed with a broad membranous wing G G. scapigera habit with cauline leaves and thyrse-like inflorescences H G. gypsicola leafy bracts (white arrow) I Selliera radicans with prostrate stems rooting at the nodes, and solitary, bracteolate, fan-like flowers in the leaf axils. Vouchers: K.A. Shepherd KS 1530 (A); K.A. Shepherd KS 1533 (B); K.A. Shepherd KS 1591 (C); K.A. Shepherd KS 1584 (D); K.R. Thiele KRT 4201 (E); DEM6887 (F); K.A. Shepherd KS 1468 (G); R. Davis s.n. (H); J.A. Cochrane & S. Barrett 4181 (I). Images: K.A. Shepherd (A–D, G); K.R. Thiele (E, I); Seeds of South Australian (F); R. Davis (H).

Clarifying the relationships among Goodenia clades A, B, C and the smaller affiliate genera was necessary in order to identify monophyletic groups for taxonomic recognition. We could not seek to make changes to Goodenia s.l. without, at minimum, full and consistent resolution of the backbone relationships and confidence in the species-level composition of each major clade. To try and address this issue, the power of next-generation sequencing was leveraged for a subset of taxa (Gardner et al. 2016a). Twenty-four taxa representative of almost all major clades within Core Goodeniaceae, including 19 accessions from Goodenia s.l. (except subsect. Scaevolina and a subset of species from subsect. Goodenia placed in Clade C), were sequenced using genome-skimming technology. The majority of coding regions of the chloroplast genome were assembled and analysed, resulting in a nearly fully resolved phylogeny for all but two nodes within Goodenia s.l. This topology was then applied as a constraint and also concatenated on an expanded matrix of 98 Core Goodeniaceae species with trnL-F and matK loci of sequence data, greatly improving phylogenetic support values. This backbone topology has been similarly utilised in the present study. The analyses of Gardner et al. (2016a) confirmed the position of Coopernookia as sister to the remainder of Goodenia s.l., followed by stepwise sisters Clade A, Clade B, and finally Velleia sister to Clade C. However, the composition and relationships of subclades within the most morphologically diverse Clade C were poorly resolved, except for the monophyly of subg. Monochila and subg. Goodenia subsect. Coeruleae. Exploration of the backbone phylogeny derived from additional genomic compartments (nuclear ribosomal complex, several single copy nuclear genes) in the study suggested alternative topologies compared to the plastid, though with low support.

To continue our investigation of alternative backbone topologies and delve into the poorly resolved Clade C, we expanded and further explored the next-generation sequencing data across nuclear, chloroplast and mitochondrial genomic compartments (Jabaily et al. 2018). We generated new genome skimming data for four additional taxa from within Clade C, and re-analysed the previously generated raw genomic data for the taxa in clade Goodenia s.l., for a total of 24 taxa. Partial mitochondrial genomes and partial chloroplast genomes expanded beyond the efforts of Gardner et al. (2016a) similarly strongly supported our original backbone relationship within Goodenia s.l. Extensive hypothesis tests were performed to explore congruencies and determine statistical support for all possible relationships within the challenging Clade C. Still, relationships between taxa and subclades within Clade C remained poorly resolved with both mitochondrial and plastid loci, as well as an expanded nuclear data set. In conclusion, while there was strong support for the monophyly of subg. Monochila and all other subclades represented distinct lineages, their position relative to each other remained unresolved, thus precluding their recognition as well-supported genera.

The Flora of Australia treatment of Goodeniaceae and Brunoniaceae (Carolin 1992a; Carolin et al. 1992) represented more than 30 years of research by Roger Carolin and his students. Over this period, Carolin’s team successively revised each genus through a series of detailed anatomical and morphological studies that culminated in the recognition of numerous new species and updated infrageneric classifications. Through his early cladistics work and study of inflorescence types, Carolin determined that there were two distinct assemblages within the Goodeniaceae (Carolin 1967a; Carolin 1977). The first was the Lechenaultia-Anthotium-Dampiera (LAD) group, united by the presence of a cymo-paniculate inflorescence, connate anthers and a base chromosome number × = 9. In contrast, the remaining genera within the ‘Goodenia group’ had a fundamentally different vascularisation of the ovary, a thyrse or raceme-like inflorescence (Figs 2G, 3, 4), free anthers, and a base chromosome number of × = 7 or 8. These broad relationships were borne out in subsequent molecular studies (Jabaily et al. 2012; Gardner et al. 2016a) (Fig. 1). Carolin (1992a) rightly pointed out that Brunonia was clearly allied to the LAD group and perhaps should not be supported as a distinct family; however, Brunoniaceae was ultimately retained for his Flora of Australia treatment due to the adoption of the Cronquist (1981) classification system by the Flora at its inception (Kanis 1981). Within his ‘Goodenia group’, Carolin (1977) also determined that the monotypic south-west Western Australian genus Diaspasis was allied to Scaevola despite the presence of connate anthers and almost radially symmetrical flowers compared to the free anthers and fan-shaped flowers typical of the widely distributed Scaevola (Carolin 1992c; 1992d); a relationship subsequently confirmed through phylogenetic analyses (Jabaily et al. 2012). Finally, Carolin (1990; 1992e) concluded that Coopernookia, Velleia, Verreauxia, and Pentaptilon were allied to Goodenia, along with the four genera Calogyne R.Br., Symphyobasis K.Krause, Neogoodenia C.A.Gardner & A.S.George, and Catosperma Benth. that were later subsumed into an expanded Goodenia.

Figure 3. 

Characterisation of inflorescence structure in Goodenia s.l. modified from Carolin (1967a) with his corresponding Bauplan ‘Type’ concepts stated were applicable and phylogenetic position for exemplar species given in brackets; MI = main inflorescence, EZ = enrichment zone, V = vegetative zone. A Form A (Type 1) is a thyrse with leafy bracts and bracteoles e.g. Goodenia ovata (Goodenia I) or (Type 2) 1(–2)-flowered raceme with leafy bracts and bracteoles e.g. G. laevis (Goodenia I) (inset) B Form B (Type 5) is a basal rosette with leafy bracts and bracteoles e.g. G. hederacea (Goodenia II) C Form C (no Type) with flowers solitary in leaf axils, leafy bracts and bracteoles e.g. G. convexa (Goodenia II) D Form D (no Type) flowers solitary in leaf axils with leafy bracts, bracteoles absent e.g. G. pumilo (Porphyranthus I) E Form E (Type 4) a basal rosette, bracteoles, with leafy bracteose bracts and either a panicle-like form e.g. G. paniculata, raceme e.g. G. gracilis (Porphyranthus II) (inset above) or a thyrse e.g. G. pterigosperma (Coeruleae) (inset below) F Form F (Type 6) with ebracteolate racemes and leafy bracts e.g. G. hispida (Ebracteolatae II), (Type 7) non-leafy bracts e.g. G. cusackiana (Ebracteolatae I) (inset above), or (Type 8) a subumbel e.g. G . pulchella (Ebracteolatae I) (inset below) G Form G (Type 3) represented by a thyrse with reduced bracts and bracteoles e.g. G. scapigera (Monochila) and H Form H (Velleia Type) is a compound dichasium with leafy bracts and bracteoles e.g Velleia lyrata (Velleia).

Figure 4. 

Diagramatic sections of ovaries (l.s.) modified from Carolin (1959). From left–right Velleia, Goodenia, Verreauxia, and Scaevola, showing fusion of floral parts and structure of the incomplete locules and placentation of ovules.

Coopernookia is the only genus in the family that shows the classic SW–SE Australian disjunction from the Nullarbor uplift around 8.8 to 0.5 million years ago (Jabaily et al. 2014), with three species endemic to the central and south west of the continent and three confined to eastern Australia (Carolin 1992b). Carolin (1967b) recognised this genus as distinct from the rest of his ‘Goodenia group’ as all species have a base chromosome number of × = 7 (rather than 8), stellate hairs on the stems and leaves, and ovoid, strophiolate seeds. The seed testa is also unique, with thickened, straight-sided cell walls that contain no mucilage in contrast to many species of Goodenia that have somewhat compressed seeds, where the epidermal cells are thickened towards the centre and thinner towards the margins and may contain mucilage that swells when wet (Carolin 1966). The flowers of Coopernookia also have retrorse barbulae inside the corolla that act as pollinator guides, reminiscent to those present in Scaevola. Indeed, Carolin (1967b) insightfully postulated that Coopernookia would have an intermediate position between Scaevola and Goodenia, which was later supported by molecular data as it was shown to be sister to Goodenia s.l. (Gardner et al. 2016a).

Goodenia is the largest and most floristically diverse genus in Goodeniaceae with c. 220 species. Species are largely confined to Australia apart from a few representatives that extend northwards to New Guinea, Indonesia, Malaysia, Philippines, and China, with a single taxon also endemic to the Island of Java (Leenhouts 1957; Carolin 1992e; Hong and Howarth 2011). Goodenia are annual or perennial herbs or low shrubs that occupy a wide variety of habitats in almost every biome across the Australian continent. Many species have yellow, white or blue bilabiate flowers (Figs 2, 5–8), although there have been multiple independent floral symmetry shifts to a fan-shaped flower form (Gardner et al. 2016b). Fruit structure, seed coat surface patterns and appendages such as wings (Fig. 2F) are also important diagnostic characters for the genus (Carolin 1980). Recently, it was determined that the genus Goodenia had been lectotypified incorrectly as the first named species, G. ramosissima Sm., is in fact a species of Scaevola (≡ S. ramosissima (Sm.) K.Krause). Consequently, a proposal was put forward to conserve the name Goodenia using the conserved type G. ovata Sm. (Shepherd et al. 2017) (Fig. 2A), which was subsequently accepted (Applequist 2019). Carolin’s (1992e) infrageneric classification currently recognises two subgenera and various sections, subsections and series (Table 1).

Figure 5. 

Goodenia Clade A phylogeny from combined nrDNA + cpDNA sequence data and exemplar taxa of major subclades. Topology is 50% majority rule cladogram from the partitioned Bayesian inference analysis. Support values above the branches are Bayesian posterior probabilities and below are maximum likelihood bootstrap values. Branch colour corresponds with support values and taxon colour corresponds to the taxonomic classification of Carolin et al. (1992). For updated taxonomy from this paper, see Tables 1, 2. Taxa represented by multiple accessions are distinguished by project code numbers as listed in Suppl. material 1. A G. ovata B Selliera radicans C G. viscida D G. calcarata; E G. tripartita F G. willisiana G G. hederacea. Images: J. Tann (A, G); R. Cumming (B); K.R. Thiele (C); Seeds of South Australia (D, F); K.A. Shepherd (E).

Figure 6. 

Goodenia Clade B_1 phylogeny from combined nrDNA + cpDNA sequence data and exemplar taxa of major subclades. Topology is 50% majority rule cladogram from the partitioned Bayesian inference analysis. Support values above the branches are Bayesian posterior probabilities and below are maximum likelihood bootstrap values. Branch colour corresponds with support values and taxon colour corresponds to the taxonomic classification of Carolin et al. (1992). For updated taxonomy from this paper, see Tables 1, 2. Taxa represented by multiple accessions are distinguished by project code numbers as listed in Suppl. material 1. A G. claytoniacea B G. purpurascens C G. pumilio D G. macbarronii E G. pinnatifida F G. nuda G G. tenuiloba H G. vilmoriniae I G. pusilliflora J G. occidentalis. Images: F. & J. Hort (A); C. Nieminski (B); R.L. Barrett (C); N. Blair (D); K.A. Shepherd (E, J); A. Perkins (F, G); R. Fryer & J. Newland (H); A. Gardner (I).

Figure 7. 

Goodenia Clade B_2 phylogeny from combined nrDNA + cpDNA sequence data and exemplar taxa of major subclades. Topology is 50% majority rule cladogram from the partitioned Bayesian inference analysis. Support values above the branches are Bayesian posterior probabilities and below are maximum likelihood bootstrap values. Branch colour corresponds with support values and taxon colour corresponds to the taxonomic classification of Carolin et al. (1992). For updated taxonomy from this paper, see Tables 1, 2. Taxa represented by multiple accessions are distinguished by project code numbers as listed in Suppl. material 1. A G. leiosperma B G. heteromera C G. heterochila D G. muelleriana E G. macroplectra F G. glandulosa G G. odonnellii H G. pilosa I G. armstrongiana (White form). Images: C. Nieminski (A, G–I); Seeds of South Australia (B, C, F); A. Perkins (D); K.R. Thiele (E).

Figure 8. 

Goodenia Clade C phylogeny from combined nrDNA + cpDNA sequence data and exemplar taxa of major subclades. Topology is 50% majority rule cladogram from the partitioned Bayesian inference analysis. Support values above the branches are Bayesian posterior probabilities and below are maximum likelihood bootstrap values. Branch colour corresponds with support values and taxon colour corresponds to the taxonomic classification of Carolin et al. (1992). For updated taxonomy from this paper, see Tables 1, 2. Taxa represented by multiple accessions are distinguished by project code numbers as listed in Suppl. material 1. A G. xanthotricha B G. coerulea C G. hassallii D G. quadrilocularis E Verreauxia reinwardtii F G. helmsii G G. sericostachya H G. stobbsiana I Velleia paradoxa J V. rosea K V. connata. Images: A. Crawford (A); F. & J. Hort (B, E–G); K.A. Shepherd (C, D, I, J); A. Perkins (H); K.R.Thiele (K).

Selliera, a genus of three fan-flowered species from Australia, New Zealand and Chile, was supported as distinct within Carolin’s (1977) ‘Goodenia group’. However, he later questioned its status (Carolin 1992f), noting that these species resembled members of Goodenia sect. Goodenia with fruits that show “a striking resemblance to that of G. koningsbergeri (Backer) Backer ex Bold. although somewhat smaller” (Carolin 1966), and he suggested that future work may determine that Selliera should be synonymised under Goodenia. This appears to be supported as a single representative of the genus, Selliera radicans Cav. (Fig. 2I), was shown to group with the unusual Scaevola collaris (Carolin 1992c) (Fig. 2B) and the fan-flowered G. viscida R.Br. (Fig. 5C) in Goodenia Clade A (Jabaily et al. 2012; Gardner et al. 2016a). Furthermore, S. radicans had been previously synonymised into Goodenia by Persoon (1805); however, subsequent workers had not taken up this proposed change.

Verreauxia, a small genus of three species from southwest Western Australia, is distinguished by unusual multi-cellular branched hairs and a unilocular ovary (Fig. 4 and Fig. 8E) that develops into an indehiscent, nut-like fruit with a single seed that (unusually) does not contain any mucilaginous cells in the seed coat testa (Carolin 1966, 1992i). Carolin (1977) also included this genus in his ‘Goodenia group’ along with the closely allied monotypic Pentaptilon, which has similar branched hairs but is distinguished by its uniquely winged ovary and fruit (Carolin 1992h). Pentaptilon together with Verreauxia formed a monophyletic group in molecular analyses within the morphologically variable Goodenia Clade C (Gardner et al. 2016a; Jabaily et al. 2018).

Velleia, the final genus in Carolin’s (1977) ‘Goodenia group’, currently includes 21 species endemic to Australia except V. spathulata R.Br., which is also found in Malaysia, western New Guinea and the Louisiade Archipelago (Leenhouts 1957; Carolin 1992g). Many species within this genus have a distinctive inflorescence structure comprised of expanded axillary dichasia (Fig. 3H). Another important diagnostic feature for Velleia is the presence of a predominantly superior ovary with the sepals, corolla and stamens usually adnate to the base (Carolin 1992g) (Fig. 2E). In contrast, the remaining Core Goodeniaceae generally have inferior ovaries, except G. macroplectra (F.Muell.) Carolin; a species in Goodenia subsect. Ebracteolatae (Jabaily et al. 2012) that has free sepals inferior to the ovary while the corolla is fused to the apex (Carolin 2007) (Fig. 7E). However, anatomical examination of Velleia ovary sections by Carolin (1959) revealed the floral parts are in fact fused to the ovary to a degree and the stamens are never fully hypogynous and in many species they appear epigynous (Jeanes 1999) (Fig. 4). Carolin (1977) stated that the flowers, fruits and seeds of Velleia are similar to those of various species of Goodenia and suggested that the morphology of the ovary was not a “reversion to an almost superior ovary but the vestiges of the former inferior condition are retained”. The infrageneric classification of Velleia, as currently recognised in the Flora of Australia, includes three sections (Carolin 1992g), based on the presence of three sepals (sect. Velleia) or five, which are either connate into a tube (sect. Euthales (R.Br.) Carolin) or free (sect. Menoceras R.Br.). While Velleia was supported as monophyletic in molecular analyses, it is placed sister to the remaining species in Goodenia Clade C (Gardner et al. 2016a; Jabaily et al. 2018).