Banksia vincentia Stimpson & P.H.Weston, 2014

Banksia vincentia Stimpson & P.H.Weston View in CoL sp. nov.

With affinities to Banksia spinulosa sensu lato, differing from other taxa in the complex by a much lower stature with stems basally prostrate from lignotuber, distally ascending.

Type: AUSTRALIA: New South Wales: South Coast: Vincentia , [precise location withheld due to conservation status], 19 May 2013, M.L. Stimpson 335, S. Harris, L. Winberg. Holotype: NSW ; Iso: NE ( Fig. 5 View FIGURE 5 ).

Lignotuberous shrub, c. twice as wide as it is high, 0.30–0.75m high x 1–2 m wide. Stems basally prostrate from a lignotuber, i.e. divergent and ± horizontal in basal 20–30 cm, then ascending to erect more distally; stems under 12 months old densely covered in a 2-layered indumentum of tightly curled trichomes forming a felted layer c. 0.2 mm thick, overtopped by a much sparser layer of straight, antrorse to patent trichomes 0.2–1.3 mm long; stems older than 12 months gradually sheading trichomes until glabrescent after about 3–4 years; axillary buds prominent in in immature leaves. Leaves narrowly oblong-obovate, rounded to truncate; petiole 1–3.5 mm long, moderately to densely covered in an indumentum resembling that of the stem, more sparse abaxially; lamina 12–47 mm long, 2–6.5 mm wide, entire or with 1–6 marginal teeth in the distal 1/5–1/15 of the lamina, sometimes with one or more toothless undulations replacing teeth, with slightly recurved margins; adaxial surface sparsely to moderately covered in a mixture of short, tightly curled trichomes and appressed, straight trichomes 0.2–0.5 mm long when immature, becoming glabrescent or with a few residual trichomes along the midvein when mature, RHS colour green group 139A–D when fresh; abaxial surface of lamina densely covered in a tomentum of tightly curled trichomes with a sparse layer of emergent, straight, appressed trichomes either side of the midvein, sparsely covered in straight, appressed trichomes without an underlying tomentum on the midvein, RHS colour greyed green group 195A–D when fresh, browning slightly on drying, becoming darker with age; adaxial midvein shallowly impressed proximally, flat distally; abaxial midvein 0.3–0.4 mm wide, prominently protruding; lamina apex mucronate. Conflorescence surrounded by a whorl of 1–4-year old branches, 75–167 mm long developing basipetally; flowers divergent, with 14–17 columns of flower pairs. Involucral bracts subulate, with abaxial spine, thickened at base, villous, 1.5–3 mm long. Common bract with one thickened keel extending from apex to base of the exposed part of the bract, silky; margins distally convex; apex rounded. Perianth yellow or cream with a white to beige indumentum of appressed, straight trichomes, to orange with ferruginous indumentum; claw 19–25 mm; limb 2.5–4 mm long. Anthers 0.5–1 mm long. Style apically hooked, 26–35 mm long from ovary to bend, 5–7 mm long from bend to apex; discolorous, green for 12–16 mm above ovary, distally grading from red to maroon to black just prior to anthesis. Infructescence of similar length to conflorescences, 125–135 mm in circumference. Figure 6 View FIGURE 6 .

Distribution: — Banksia vincentia is restricted to a small area near Vincentia on the south coast of New South Wales.

Derivation of Epithet: —The specific epithet is a noun in apposition that refers to the named place nearest to the only known location of this species.

Ecology:— Banksia vincentia grows in sclerophyllous shrubland dominated by Allocasuarina littoralis , B. ericifolia , Hakea teretifolia with Persoonia mollis , Lambertia formosa , Isopogon anemonifolius , H. laevipes , Aotus ericoides , and species of Restionaceae and Cyperaceae , in sandy soil over clay on sandstone. Banksia vincentia grows within 0.1 km of populations of B. ericifolia , B. spinulosa and B. paludosa , although those species occur in different microhabitats. Banksia vincentia is a lignotuberous shrub and presumably resprouts after fire. B. vincentia produces many conflorescences but very few infructescences. The plants of B. vincentia in the wild show signs of severe foliar herbivory, while specimens in cultivation from cuttings at UNE show no such signs.

Suggested conservation status: —Of the 14 individuals now known, six are reproductively mature and producing seed, while the remaining eight appear to be dying, probably due to poor drainage of the site relating to construction and presence of a road dividing the population. All specimens of this plant were found within a radius of 60 m. Compared with species of Banksia listed under the Environment Protection and Biodiversity Conservation Act (1999), Banksia sp. Jervis Bay has the smallest population and most restricted distribution of all endangered or critically endangered species of Banksia .

Given the low numbers of individuals, we consider the species should be listed as ‘Critically endangered’ according to Threatened Species Conservation Act (1996) of NSW. Accordingly, the precise locality of B. vincentia has been withheld. The process of nominating B. vincentia as critically endangered is in progress. We hypothesise that this species is a rare relictual species and we aim to test this hypothesis.

Flowering Phenology: —Resting conflorescence buds start to expand in late December to early January. Conflorescences are fully developed by early April to May. Flowering continues until late June.

Similar Species: — Banksia vincentia differs from all other species of Banksia in that the stems are prostrate, radiating from a lignotuber for 20–30 cm then ascending to erect more distally. Banksia vincentia most closely resembles B. neoanglica , from which it also differs in its usually lower stature at reproductive maturity (plants to 6 m tall in B. neoanglica ).

Selected specimens: — Australia, New South Wales: South Coast, Vincentia : 7 February 2009, M.L. Stimpson 46a ( NE) ; 7 February 2009, M.L. Stimpson 47a ( NE) ; 14 Mar. 2009, M.L. Stimpson 59 ( NE, NSW) ; 20 February. 2010, M.L. Stimpson 124 ( NE) ; 16 Mar. 2012, S. Harris ( NE: NE99429 ) .