Levenhookia leptantha Benth., Fl. Austral. 4: 35. 1868

Wege, Juliet A., 2020, Styleworts under the microscope: a taxonomic account of Levenhookia (Stylidiaceae), PhytoKeys 151, pp. 1-47 : 1

5. Levenhookia leptantha Benth., Fl. Austral. 4: 35. 1868 Figs 1B , 2C-E , 4D

Leewenhoekia leptantha , orth. var.: F. von Mueller, Syst. Census Austral. Pl.: 86 (1882).

Type.

Australia. Western Australia: ' Drummond, n. 128, 175, 282; Champion Bay and Murchison river, Oldfield; also a few specimens mixed in Preiss’s n. 2249 from Sussex district.' Murchison River. Thicket south of Collallia [Colalya Creek], [1859-1860] A.F. Oldfield 337 (lectotype, here designated: MEL 2257568; isolectotype: K 000060047); Champion Bay, Western Australia, A.F. Oldfield s.n. (syntype: MEL 2257566); Swan River, [?1843-1844] J. Drummond [?3:]128 (syntype: K 000060046); Swan River, [1844-1847] J. Drummond 4: 175 (syntypes: BM 001041269, CGE, G 00358743, G 00358744, K 000060044, K 000060048, MEL 2295753, P 00712439, W); Swan River, [1842] J. Drummond 2: 282 (syntypes: BM 001041268, CGE, G 00358741, G 00358742, K 000060042, K 000060045, OXF, MEL 2295752, P 00712440, W); districtus Sussex, 20 Dec 1839, L. Preiss 2249 (excluded syntype: MEL 2295747 p.p.), = L. aestiva [note: this gathering is also a syntype of L. preissii ].

Description.

Annual herb 2-10 cm high. Glandular hairs 0.15-0.5 mm long. Stem reddish brown to dark red, simple (rarely once-branched at base), glandular-hairy. Leaves cauline, scattered, reddish to reddish brown; lamina succulent, usually lanceolate, ovate or elliptic, sometimes obovate or narrowly oblanceolate, 1-8 mm long including the petiole, 0.5-3 mm wide, subacute or acute, glandular-hairy abaxially and on the margins (sometimes sparsely so). Flowers usually in umbels, sometimes in short racemes, 1-30 per plant; bracts succulent, lanceolate, ovate or elliptic (sometimes narrowly so), 1-7 mm long, glandular-hairy like the leaves; pedicels 0.5-5 mm long, glandular-hairy. Hypanthium globose, ellipsoid or obovoid, 0.7-2 mm long, 0.6-1.7 mm wide, glandular-hairy. Calyx lobes ± equal, 0.8-2 mm long, acute, glandular-hairy. Corolla bright pink (rarely white) with a yellow (rarely creamy white) throat and dark pink or pink-red throat markings on each lobe (rarely absent), white abaxially; lobes evenly arranged or ± paired vertically, spreading to scarcely recurved, obovate, emarginate, retuse or incised, glabrous or with sparse glandular hairs abaxially near the base; anterior (lower) lobes ± equal in size or scarcely longer and broader than the posterior (upper) pair, 2-5.5 mm long, 2-4.5 mm wide; posterior lobes 1.8-5 mm long 1.8-4 mm wide, basally connate for 0.5-1 mm; tube creamy white or yellowish with pink longitudinal streaks, 3-9 mm long, 1.7-5 mm longer than the calyx lobes, sparsely glandular-hairy distally. Labellum ventral, 0.9-1.2 mm long including a short claw to ca. 0.2 mm long; hood yellow (rarely creamy white), usually with dark maroon markings near the cleft, sparsely glandular-hairy (mostly abaxially); appendage at the cleft apex yellow, ovate, elliptic or oblong, 0.2-0.5 mm long, minutely papillate, sometimes also with 1 or 2 glandular hairs; basal appendages yellow, rounded, 0.2-0.4 mm long, minutely papillate. Column sheath bright yellow (rarely pale greenish yellow), glabrous, with rounded anterior and lateral lobes 0.2-0.5 mm high, connate with the posterior corolla lobes forming a smooth, thickened pad, pendulous appendages absent. Column yellow, adnate to the anterior side of the corolla tube, 4.2-10 mm long with the top 0.7-1.1 mm free and slightly forward-arched when enclosed by the labellum, sparsely glandular-hairy distally on the anterior side; stigmatic lobes to ca. 0.6 mm long, the lower-most sharply upturned and developing while the column is hooded, the uppermost incurved and developing later. Mature capsules and seed not seen.

Diagnostic features.

Levenhookia leptantha has succulent floral bracts, a long (3-9 mm) corolla tube and comparatively short (0.8-2 mm long) calyx lobes, and minute glandular hairs at the tip of the column. Its corolla lobes are usually bright pink with a yellow base and the labellum has a morphologically distinct apical appendage that can be discerned on pressed material.

Phenology.

Flowering from late August to October.

Distribution.

Levenhookia leptantha is widespread in south-western Australia (Fig. 4C ), although largely absent from the high rainfall zone, with most records occurring in the Geraldton Sandplains, Yalgoo, Avon Wheatbelt and Coolgardie bioregions. There are scattered occurrences in the Murchison and Mallee bioregions and an isolated record from the Swan Coastal Plain near Muchea.

Habitat.

Levenhookia leptantha grows in sand, sandy loam, sand over clay or clay loam on plains and gentle hill-slopes, often in association with granite outcropping, salt lakes, creek-lines or seasonally wet claypans. Associated vegetation is varied and includes open Eucalyptus woodland, mallee shrubland, tall shrubland or scrub with Acacia , Allocasuarina , Melaleuca or Eremophila , and halophytic dwarf shrubland. It is often found in more open areas of habitat growing with other ephemeral herbs.

Conservation status.

This widespread species is not currently considered to be at risk ( IUCN 2012: Least Concern).

Etymology.

From the Greek lepto - (slender-) and anthos (flower): the flowers can appear narrow in pressed material due to their long and slender corolla tube.

Vernacular name.

Trumpet Stylewort ( Erickson 1958).

Typification.

Bentham examined several gatherings when describing L. leptantha , including "a few specimens mixed in Preiss’s n. 2249" (a syntype of L. preissii ). MEL 2295747 bears his corresponding annotation "These specimens seem rather to belong to L. leptantha , the lower ones to L. preissii "; however, I am at a loss to explain Bentham’s interpretation of this material. All individuals on this sheet appear referable to L. aestiva (refer to the typification section under L. preissii ). A lectotype must therefore be selected from amongst the remaining material to fix the application of the name L. leptantha . MEL 2257568 has been selected since it is the best quality material with specific locality information that was viewed by Bentham. It bears a Botanical Museum of Melbourne label with the locality "Murchison River" as given by Mueller, an Oldfield label with the annotation "337. Fl. Pink. Moist places. Thicket south of Collallia" [Colalya Creek, which drains into the Murchison River east of Meekatharra] and a slip with "Gerald river Murchison" in Bentham’s hand. Bentham also retained a subset of this material at K.

Illustrations.

R. Erickson, Triggerplants 201, Pl. 57, No. 4 and 212, Pl. 59, Nos. 1-5. 1958 [only the free, distal portion of column depicted]; B.J. Grieve & W.E. Blackall, How to know W. Austral. wildfl. 4: 766, no. 5. 1982.

Selected specimens examined.

Australia. Western Australia: Bolgart, 40 km N of Perth, 29 Sep 1949, R. Erickson s.n. (PERTH); ca. 100 km E of Southern Cross, 26 Sep 1997, B.A. Fuhrer 97/19 (PERTH); 29 miles [46.7 km] W of Mount Magnet, 11 Sep 1966, A.S. George 79676 (PERTH); Gayon Station, Cue Road, Mullewa, 19.4 km NE of Courin Hill, 8 Oct 2004, F. Hort, J. Hort & J. Shanks 2340 (PERTH); Emu Rock, Holland Track, 6 km SW from Hyden Norseman Rd, 22 Sep 2005, R.W. Purdie 6097 (CANB, PERTH); Avon Loc, 19405, 1 mile [1.6 km] SW of Manmanning, 7 Oct 1988, B.H. Smith 1101 (BRI, CANB, MEL); 850 m S along Wicherena Rd from Geraldton - Mt Magnet Rd, 12 Sep 1996, J.A. Wege 194A & K.A. Shepherd (PERTH); ca. 3.2 km E of Yellowdine on Great Eastern Highway, 13 Sep 2003, J.A. Wege 895 & C. Wilkins (PERTH); E of Canna Siding, 14 Sep 2011, J.A. Wege 1828 & K.R. Thiele (MEL, PERTH); ca. 3.1 km E of Great Northern Hwy on Goodlands Rd, NE of Jibberding Rocks, 12 Sep 2018, J.A. Wege 2063 (MEL, PERTH); Bungabandi Creek on Eurardy Station, N of the Murchison River, 30 Aug 2003, Wildflower Society of WA EURA 525 (PERTH).

Figures

Figure 1. Levenhookia is a genus of annual herbs endemic to Australia A distribution in temperate and semi-arid regions of Australia, scale bar 1000 km B L. leptantha (J. A. Wege 2063) C L. pusilla (J. A. Wege 1749 & W. S. Armbruster) D L. octomaculata (J. A. Wege 2074) E L. pulcherrima (J. A. Wege 1937). Photos by J. A. Wege.

Figure 2. Labellum and column movement in Levenhookia. Black arrow = labellum hooded over column; white arrow = labellum ' triggered' to release column; yellow arrow = labellum repositioned following column release; blue arrow = column position immediately following release from labellum A L. stipitata (unvouchered, Augusta area, Western Australia) B L. aestiva (J. A. Wege 2090) C-E L. leptantha (J. A. Wege 2063), with labellum enclosing the column (C), triggered to release the column which moves to the opposite side of the flower (D) and subsequently repositioned (E) with the stigmatic lobes developed F L. aestiva (J. A. Wege 2090), labellum triggered with column momentum stopped by the sheath at the base of the corolla lobes G, H L. pauciflora (at J. A. Wege 1071 & C. Wilkins): note the unusual, distally-angled column and brush-tipped labellum I L. murfetii (J. A. Wege 2060): note the dorsal position of the labellum; J, K L. dubia, with the labellum opening (but not otherwise moving) to release the column (K). Photos by R. W. Davis (A, B) and J. A. Wege (C-K).

Figure 4. Comparative distributions and floral morphologies A, B Levenhookia dubia, with a widespread distribution across southern Australia and flowers with acute calyx lobes and a simple, sessile labellum (K. R. Thiele 3360) C, D L. leptantha, a widespread Western Australian endemic with an exserted corolla tube and fleshy bracts (J. A. Wege 1828) E, F L. pulcherrima, a poorly-known Western Australian endemic with an exserted corolla tube and distinctive corolla lobe shape and markings (J. A. Wege 1937). Photos by K. R. Thiele (B, D) and J. A. Wege (F). Scale bar on maps 1000 km.