Geleznowia Turcz.

Anderson, Benjamin M., Binks, Rachel M., Byrne, Margaret, Crawford, Andrew D. & Shepherd, Kelly A., 2023, Using RADseq to resolve species boundaries in a morphologically complex group of yellow-flowered shrubs (Geleznowia, Rutaceae), Australian Systematic Botany 36 (4), pp. 277-311 : 293

Geleznowia Turcz. , Bull. Soc. Imp. Naturalistes Moscou 22(3): 12–13 (1849)

Type: G. verrucosa Turcz.

Erect subshrubs to shrubs 0.15–2 m high, branchlets terete, glandular–verrucose, glabrous or with an indumentum of simple hairs. Leaves sessile or with a short petiole, overlapping and crowded towards terminal branches, coriaceous, elliptic to obovate, glandular–verrucose adaxial surface, with or without short, simple hairs. Flowers 1–17 in terminal heads. Bracts 0–14 petaloid, yellow, surrounding flowers. Sepals 5, free, 3.5–14 mm long, imbricate and resembling bracts. Petals 5, yellow, elliptic, thicker than sepals, 4–8.8 mm long. Stamens 10, free, 2.5–5.5 mm long, glabrous. Carpels 5, free, thickened at the apex, glandular–verrucose, with two ovules per carpel; style glabrous, with a narrow to club-shaped stigma. Fruit obovoid with a single seed per locule. Seeds dark brown to black 3.6–5 mm long, with a pale aril.

Distribution

A genus of seven species endemic to Western Australia ( Fig. 8 ).

Etymology

Named for Nikolai Ivanovich Zheleznov (1816–1877), an agronomist at Moscow University ( Turczaninow 1849).

Key to the species of Geleznowia

1. Moderate to tall shrubs 0.6–2 m high; leaves silvery green; inflorescence of dense heads 15–33 mm long, each with 5–17 flowers; bracts and sepals vivid yellow

2. Habit 1–2 m high; maximum 17 flowers per inflorescence; 8–10 bracts; stigma narrower than the style, 0.1–0.3 mm wide (Kalbarri National Park area)................................. G. amabilis

2: Habit 0.6–0.75 m high; maximum 7 flowers per inflorescence; 6 or 7 bracts; stigma broader than the style, 0.4–0.5 mm wide (north Geraldton)....................................................... G. eximia

1: Moderate shrubs 0.2–1.2 m high; leaves glaucous, pale green to dull dark green; inflorescence of solitary flowers or dense heads 5.2–23 mm long, each with 1–10 flowers; bracts and sepals pale lemon yellow, yellow or greenish-yellow (some of which may be strongly tinged red post-pollination)

3. Inflorescence with (5)7–10 flowers; bracts, bracteoles and sepals pale lemon yellow with moderately dense to dense long hairs up to 1.2 mm (north Geraldton to north Kalbarri)...... .......................................................................... G. narcissoides

3: Inflorescence with 1–7 flowers; bracts, bracteoles and sepals pale greenish-yellow to yellow, glabrous or with scattered to moderately dense short hairs up to 0.1 mm

4. Inflorescence 5.2–15 mm long; bracts 3.7–8.6 mm long, 1.8–5.5 mm wide; sepals 5–9.3 mm long, equal to or slightly longer than petals (ratio 1.09–1.24)

5. Inflorescence 12–15 mm long; few bracts (0–3(4)) surrounding 1–6 flowers; bracts 2.4–5.5 mm wide; bracteoles variable 0–8 (east Watheroo to Dirk Hartog Island)...... G. verrucosa

5: Inflorescence 5.2–10 mm long; numerous bracts ((4)5–7) surrounding 1–3(5) flowers; bracts 1.8–2.9 mm wide; bracteoles infrequent 0–2(4) (west Coorow to east Goomalling)...... ................................................................................ G. occulta

4: Inflorescence 12–22 mm long; bracts 6.8–16.9 mm long, 4–10.3 mm wide; sepals 9–12.8 mm long, obviously longer than petals (ratio 1.45–1.8)

6. Flowers usually 5–7 (sometimes 1–4) per inflorescence; numerous bracts (7)10–14; numerous bracteoles 8–12; peak flowering August–September (west Gillingarra to south Shark Bay).............................................. G. calycina

6: Flowers usually 1–3 per inflorescence; fewer bracts (5)6–8; fewer bracteoles 0–6; peak flowering May–July (southeastern Goomalling to Kalbarri area)............ G. uberiflora

Figures

Fig. 8. Distributions of all seven Geleznowia species in Western Australia. The base map is sourced from GADM (ver. 3.6, see https://gadm.org), with grey borders showing IBRA regions and subregions (Department of Agriculture, Water and the Environment 2020).