Resolution of the Eremophila tietkensii (Scrophulariaceae) species complex based on congruence between morphological and molecular pattern analyses Author Curtis, Amy L. Author Grierson, Pauline F. Author Batley, Jacqueline Author Naaykens, Jeremy Author Fowler, Rachael M. Author Severn-Ellis, Anita Author Thiele, Kevin R. text Australian Systematic Botany 2022 2022-03-02 35 1 1 18 http://dx.doi.org/10.1071/sb21005 journal article 10.1071/SB21005 1446-5701 10903891 Eremophila tietkensii F.Muell & Tate, Trans. Proc. & Rep. Roy. Soc. S. Australia 8: 109 (1890) Type : Laura Vale , Northern Territory , [June] 1889, W . H . Tietkens s.n. (holo: MEL 82820 ) . Eremophila latrobei var.tietkensii (F.Muell.& Tate) Ewart & P.H.Jarrett [see https://id.biodiversity.org.au/name/apni/114129/api/apni-format], Proc. Roy. Soc. Victoria 40: 87 (1928) [see https://id.biodiversity.org.au/ instance/apni/548054]. Eremophila pachomai Paczkowska & A.R.Chapman, W. Austral. Fl. Descr. Cat. 339 (2000), nom. inval. [manuscript name; no Latin description or diagnosis provided or referenced] Eremophila sp. Rudall River ( P . G . Wilson 10512), Western Australian Herbarium: L . J . Biggs & C . M . Parker, Nuytsia 23:504 (2013) . Rounded to flat-topped shrub 0.6–2(−3) m tall, aromatic. Young stems covered 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, pale greyish-green or grey, petiolate; petioles (2.5–)5–10(–16) mm long; lamina ovate to lanceolate, (19–)32–57(–91) × (4–)10–21(–32) mm, smooth; indumentum dense, very short, appressed, white to grey, velutinous, often matted-resinous, comprising simple, uniseriate hairs, the terminal cell much longer than the others and usually attenuate; margins entire; apex acute, attenuate, or mucronate. Flowers 2–4 per axil, pedicellate; pedicels (5–)10–14(–25) mm long, with indumentum as for stems. Sepals 5, imbricate, subequal, elliptic to oblanceolate, broadly acute to obtuse with a mucro, (7–)10–13(–18) × (1.5–)3–5(–7) mm, pinkish-purple to mauve, maroon or red, pubescent with ±appressed, tangled hairs, the margins more densely so, enlarging after flowering and then glabrescent and with prominent veins. Corolla 22–28 mm long, pale blue, blue, pale lilac to pale mauve, white tinged lilac, mauve or pink; outer surface of lobes and tube with scattered eglandular hairs particularly near the margins, often almost glabrous; mid-inner tube with moderate density of eglandular hairs. Stamens 4, included; filaments with long eglandular hairs towards base, glabrous above; anthers glabrous. Ovary ovoid-oblong, densely glandular-puberulous with scattered or numerous longer eglandular hairs; style glabrous or with a few scattered, simple, spreading, short eglandular hairs. Fruit dry, woody, ovoid-conical, ±beaked, ribbed, 6–7 × 3–4.5 mm ; exocarp adhering to endocarp, glandular-puberulous but usually with some longer eglandular hairs, occasionally resinous; endocarp vertically ribbed, splitting into four segments towards apex. Distribution and habitat Occurs from Exmouth on the western coast of WA in the Carnarvon IBRA bioregion ( Thackway and Cresswell 1995 ) to just over the NT border in the east, throughout the Pilbara, Gascoyne, Little Sandy Desert, Great Sandy Desert, Gibson Desert and Central Ranges IBRA bioregions, and down to the Murchison bioregion to the south. Occurs on a range of substrates and landscape positions, including red−brown sand, silty loam, skeletal loam over ironstone, rocky quartz, gravel, laterite, dolerite, and limestone on flats, undulating plains, saline clay plains, plateaus, gully slopes, valley floors, creeklines, scree slopes, and outcrops (Western Australian Herbarium’s FloraBase, see https:// florabase.dpaw.wa.gov.au/). Phenology Flowers in late winter to at least mid-spring, with fruits maturing from early spring onward. Conservation status Eremophila tietkensii is widespread in WA , including in several national parks and nature reserves, and is not considered to be under threat. It is known in the NT only from regions close to the WA border between Lakes Mackay and Neale. Notes Eremophila tietkensii is a widespread and morphologically variable species. It differs from E. naaykensii in having shorter pedicels (shorter than or similar in length to the flowers cf. usually longer than the flowers) among less dense leaf clusters at branch apices, and having leaf indumentum trichomes with an elongated terminal cell, and from E. hurteri in its glandular-puberulous cf. densely silky ovary indumentum. Plants from the vicinity of the Rudall and Oakover Rivers have leaves that are generally shorter and more ovate than is typical, and these populations were previously segregated as Eremophila sp. Rudall River. However, the differences in leaf shape are continuous and highly variable. Some plants distant from the Rudall-Oakover area have equally small leaves, while some plants from within that area have longer, more lanceolate leaves. Two disjunct, far-western collections from the Cape Range are typical for the species. Selected specimens examined WESTERN AUSTRALIA . 17 km on Exmouth Road, Exmouth, Anonymous D 11305 ( PERTH 03856208); 25.4 km NW of Cobra on the Gifford Creek Road, Upper Gascoyne, R . J . Chinnock 6888 ( PERTH 08316937); The Gap, 1.4 km N of the turnoff to Christmas Pool, Paterson Range, R . J . Chinnock 6965 ( PERTH 08317186); Mu Hills, Ngaanyatjarraku, R . J . Chinnock 8002 ( PERTH 08669945); 12.5 km N of Towrana, R . J . Chinnock 8002 ( PERTH 08316945); 21.4 km N of Gascoyne Junction, R . J . Chinnock 3796 ( PERTH 08316899); Yalthalla Creek near Mount Rica, Hamersley Range, Ashburton, C . A . Gardner 6420 ( PERTH 03856275); 20 km WSW Parngurr, Little Sandy Desert, P . K . Latz 17817 ( PERTH 08305447); Rudall River district, ∼ 500 km S of Broome, P . G . Wilson 10512 ( PERTH 03878740).