Eremophila naaykensii A.L. Curtis & K. R. Thiele, 2022

Curtis, Amy L., Grierson, Pauline F., Batley, Jacqueline, Naaykens, Jeremy, Fowler, Rachael M., Severn-Ellis, Anita & Thiele, Kevin R., 2022, Resolution of the Eremophila tietkensii (Scrophulariaceae) species complex based on congruence between morphological and molecular pattern analyses, Australian Systematic Botany 35 (1), pp. 1-18 : 15

Eremophila naaykensii A.L. Curtis & K. R. Thiele , sp. nov.

Eremophila sp. Hamersley Range ( K. Walker KW 136) Western Australian Herbarium: L. J. Biggs & C. M. Parker, Nuytsia 23: 504 (2013).

Type: Hamersley Range (specifically Hancock Range ) within mining tenement E-47/ 1329- I neighbouring Mining Area C , within Juna Downs Street, ∼ 103 km WNW of Newman townsite, 5 km E of Great Northern Highway, Western Australia, 21 Feb. 2018, C. van den Bergh CV Opp 18 (holo: PERTH 09105972 !) .

Rounded to obconical shrubs or small trees 1–2.5(–3.5) m tall, aromatic. Young stems clothed in a persistent, fine, grey to yellowish, appressed tomentum of simple hairs, obscurely tuberculate beneath the indumentum; older stems with grey to very pale grey, slightly fissured bark, at first with prominently raised and knob-like persistent leaf bases. Leaves scattered but tending to be clustered towards the stem apices, pale green or grey-blue, petiolate; petioles (6–)9–13(–18) mm long; lamina lanceolate, (37–)55–71.5(–89) × (5–) 7.5–12(–15) mm, smooth; indumentum dense, very short, appressed, white to grey, velutinous, often matted-resinous, comprising simple, uniseriate hairs that are evenly septate, the terminal cell no longer than the others and with a bluntly rounded tip; margins entire; apex attenuate. Flowers (1)2–4 per axil, appearing clustered in the dense, terminal leaf clusters, pedicellate; pedicels (20–)28–33.5(–40) mm long and ±sigmoidal, with indumentum as for stems. Sepals 5, imbricate, subequal, elliptic to oblanceolate, broadly acute to obtuse, sometimes mucronate, (7–)8–10(–14) mm × (2.5–) 3–5(–6), yellowish, greenish, red or purple-tinged in flower (likely to be colouring further after anthesis), pubescent with ±appressed, tangled hairs, the margins more densely so, enlarging after flowering and then glabrescent and with prominent veins. Corolla 20–28 mm long, cream, pale blue, lilac, yellow, pink or purple sometimes with spots on upper lobe, the throat and inside of tube pale yellow to cream; outer surface of lobes and tube with scattered eglandular hairs particularly near the margins, often almost glabrous; mid-inner tube with moderately dense eglandular hairs. Stamens 4, included; filaments with long eglandular hairs towards base, glabrous above; anthers glabrous. Ovary sparsely to moderate pubescent with glandular and eglandular hairs, ribbed; style with short, patent, eglandular hairs for most of its length. Mature fruits not seen.

Distribution and habitat

Endemic in the Pilbara IBRA bioregion ( Thackway and Cresswell 1995). Current records indicate a geographic range of ~ 200 km from west to east in the southern half of the central to eastern portions of the Hamersley Ranges, occurring from the vicinity of Paraburdoo east to north-west of Newman (Western Australian Herbarium’s FloraBase, see https://florabase.dpaw.wa.gov.au/). Generally found in rocky ranges of the Hamerseley Plateau, often high in the landscape on the tops of ironstone ranges, breakaways and on upper slopes, often in and around rocky gullies and gorges, associated with low open Eucalyptus leucophloia and Corymbia ferriticola woodlands with mixed Acacia aneura sens . lat. and Acacia spp. open shrublands and tall shrublands.

Phenology

Flowers in late winter to at least mid-spring, often seasonally dependent, with fruits maturing from early spring onward.

Conservation status

Eremophila naaykensii is currently known from six populations and is listed as a Priority Three species under the Conservation Codes for Western Australian flora, under the name E. sp. Hamersley Range ( K. Walker KW 136; Western Australian Herbarium’s FloraBase, see https://florabase. dpaw.wa.gov.au/).

Etymology

Named in honour of Jeremy Naaykens, Senior Advisor Riparian Ecology and Botany at Rio Tinto Australia. Jeremy has contributed much to our knowledge of the flora of the Pilbara region, and has collected specimens from most known populations of Eremophila naaykensii . His enthusiasm for the species often led to his disappearance up rocky ravines and gorges to collect specimens when other more pressing work was required.

Notes

Eremophila naaykensii was previously included in E. tietkensii , from which it can be distinguished by the presence of evenly septate hairs with rounded tips on the adaxial and abaxial leaf blades, leaves that are densely clustered at the stem apices (not terminally clustered in E. tietkensii ), and pedicels longer than the flowers (generally the same length as the flower in E. tietkensii ). It almost certainly belongs in the clade of Eremophila that contains sections Eremaeae, Pulchrisepalae, Eremophila and Eriocalyx Benth. ( Fowler 2018) . However, phylogenetic relationships within this clade are poorly resolved with low support, and the precise phylogenetic relationships of E. naaykensii are currently unknown.

Selected specimens examined

WESTERN AUSTRALIA. [precise localities withheld for conservation reasons] J. Bull & J. Waters ONS PH 62.04 ( PERTH 09126120); S. Reiffer & H. Ajduk WPT 1- TS ( PERTH 08772088); S. van Leeuwen 3723 ( PERTH 06023983); S. van Leeuwen 3828 ( PERTH 06110134); S. van Leeuwen 4074 ( PERTH 06017339); M. E. Trudgen MET 17478 ( PERTH 06653561).