Geleznowia uberiflora K.A.Sheph. & A.D.Crawford, 2023

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 : 304-306

Geleznowia uberiflora K.A.Sheph. & A.D.Crawford , sp. nov.

Type: Western Australia, 1.3 km W of Murchison House Access Road on the Ajana–Kalbarri Road , E of Kalbarri , 21 Aug. 2020, K. A. Shepherd & C. F . Wilkins KS 1734 (holo: PERTH 09507914 ; iso: CANB, K, MEL, NSW, NY, P) .

Erect single- or multiple-stemmed subshrub or shrub 0.25– 0.8 m high; older branches light brown to light grey–brown and glabrous, younger branches yellowish-green with an indumentum of scattered to moderately dense, simple hairs up to 0.1 mm long. Leaves glaucous green to dull green, elliptic, 3–9 mm long, 2–5.8 mm wide, adaxial surface slightly concave and glabrous or rarely with scattered hairs 0.05 mm long, abaxial surface glandular–verrucose, glabrous. Flowers 1–3 (rarely 4–5), yellow, terminal inflorescences 12–19 mm long. Pedicel of central flower (2) 3–4 mm long with dense hairs 0.2–0.5 mm long. Bracts (5) 6–8, pale greenish-yellow to yellow, rarely tinged red at the apex post-pollination, elliptic to broadly obovate, 6.8– 14 mm long, 4–10 mm wide, adaxial surface glabrous or with scattered hairs up to 0.05 mm long; abaxial surface glandular–verrucose, glabrous. Bracteoles 0–6, usually paired below each flower except central flower, narrowly elliptic to narrowly obovate, 5.1–10.1 mm long, 2.4–4.2 mm wide, adaxial surface glabrous or with scattered hairs up to 0.05 mm long; abaxial surface glabrous or with scattered hairs up to 0.05 mm long. Sepals elliptic, 9–12.8 mm long, (4) 5–8.3 mm wide, adaxial surface glabrous or with scattered hairs up to 0.05 mm long; abaxial surface faintly glandular–verrucose, glabrous or with scattered hairs up to 0.05 mm long. Petals yellow, narrowly elliptic to elliptic, cupped, coriaceous, 5–8.8 mm long, 2.2–3.5 mm wide, glabrous or with a few scattered hairs up to 0.05 mm long. Stamens 10; filaments 3.1–5.5 mm long, 0.3–0.5 mm wide at the base, glabrous; anthers oblong, 1.3–1.7 mm long, 0.4–0.7 mm wide. Carpels 5, free, with two ovules per carpel, total length 3–5 mm, total width 3.2–5.8 mm; verrucose, glabrous or with hairs 0.1–0.25 mm long. Style glabrous, 3.5–4.5 mm long, 0.2–0.4 mm wide; stigma obovoid, broader than style apex, 0.2–0.3 mm long, 0.5–0.6 mm wide. Fruit obovoid, 6–7.3 mm long, 7–10.5 mm wide. Seeds dark brown to black 4.6–5.2 mm long, 2.7–3.3 mm wide; aril pale cream 1.6–3.2 mm long ( Fig. 1 b , 14 ).

Distribution and habitat

This species is reasonably widespread through the northern sandplains from south-east of Goomalling and west of Dalwallinu to the Kalbarri region ( Fig. 8 ) in the Avon Wheatbelt, Swan Coastal Plain, and Geraldton Sandplains bioregions (Department of Agriculture, Water and the Environment 2020). Found on flat sandplains or gentle slopes growing in yellow, brown or white sand sometimes with laterite. This species also responds to disturbance because young plants can be found on graded road verges and in recently burnt habitats. Occurring in open mallee, woodland, shrublands or dense low heath, associated with Allocasuarina , Banksia , Acacia , Callitris , Conospermum , Grevillea , Synaphea and Verticordia .

Phenology

Peak flowering from August to September with fruits beginning to form in late September through to October.

Conservation status

This species is widespread and represented within the conservation estate and therefore is not currently considered to be under threat.

Etymology

From the Latin uber (fruitful, abundant) and - florus (-flowered), in reference to the numerous showy yellow flowers typical of this species.

Notes

Geleznowia uberiflora can be morphologically delineated from other members of the genus by virtue of the following combination of characters: subshrub or shrub 0.25–0.8 m high with glaucous green to dull green leaves; 1–3 (rarely 4 or 5) flowers per inflorescence, surrounded by (5)6–8 pale greenish yellow to yellow bracts, 6.8–14 mm long, 4–10 mm wide, abaxial surface glabrous; sepals elliptic, 9–12.8 mm long, (4) 5–8.3 mm wide; and a broad stigma 0.5– 0.6 mm wide. For comparison, see notes under G. calycina .

One population from south of Eneabba ( K. A. Shepherd & C. F. Wilkins KS 1712 ( PERTH 09507817)) was detected as genomically divergent (Group P 4) and is provisionally identified here as a hybrid G. uberiflora × occulta .

Selected specimens examined

WESTERN AUSTRALIA. Gravel Reserve E of White Gums Nature Reserve, 2 Oct. 2004, A. Crawford ADC 580 ( PERTH 07118244 ); Simpson Road 7.2 km E of the Morawa – Three Springs Road, 30 Sep. 2007, A. Crawford ADC 1357 ( PERTH 07752180 ); Burma Road NR, 5.7 km E of the western firebreak along central track, E of Walkaway , 3 Oct. 2007, A. Crawford ADC 1391 ( PERTH 07752202 ); Masons Road, 5.7 km N of Carot Well Road , NE of Watheroo, 12 Nov. 2007, A. Crawford 1564 ( PERTH 07752326 ); Gravel Reserve E of White Gums Nature Reserve , 9 Sep. 2008, A. Crawford ADC 1839 ( PERTH 08202095 ); E of White Gums Nature Reserve, ~ 0.7 km W of First North Road on the Eneabba – Three Springs Road ( E of Eneabba ), 9 Sep. 2008, A. Crawford ADC 1840 ( PERTH 08201129 ); Nature Reserve, E of intersection of Nambling South Road and Hagboom West Road , 22 Nov. 2011, A. Crawford ADC 2110 ( CANB 823253 , PERTH 08397201 ); ~ 400 m E of creek, Depot Hill Reserve , ~ 10 km NW of Mingenew, 7 Sept. 2007, R. Davis 11223 (DNA D0190324, PERTH 07748744 , PERTH 07748752 ); on N side of Nabbewa – Yetna Road, 3.2 km NE of Nanson – Howatharra Road, UCL , ~ 5 km SW of Nabawa , 30 Sep. 1998, N. Gibson 4333 ( PERTH 07055501 ); 11.1 km E of Brand Highway on Coorow – Greenhead Road, SE of Eneabba , 30 Aug. 2021, K. A. Shepherd & B. M . Anderson KS 1824 ( MEL, PERTH 09507892 ); White Gums Nature Reserve, 1 km E of Brimson Road on the Eneabba – Three Springs Road, E of Eneabba then 700 m along track through the gravel pit, 30 Aug. 2021, K. A. Shepherd & B. M . Anderson KS 1828 ( NSW, PERTH 09507906 ); 11.1 km E of Brand Highway on Coorow – Greenhead Road, SE of Eneabba , 17 Aug. 2020, K. A. Shepherd & C. F . Wilkins KS 1710 ( CANB, MEL, NSW, PERTH 09507957 ); White Gums NR, 1 km E of Brimson Road on the Eneabba – Three Springs Road, E of Eneabba , 18 Aug. 2020, K. A. Shepherd & C. F . Wilkins KS 1715 ( CANB, MEL, NSW, P, PERTH 09507965 ); Wotto NR, near the corner of First North Road and the Eneabba–Three Springs Road , E of Eneabba, 18 Aug. 2020, K. A. Shepherd & C. F . Wilkins KS 1716 ( CANB, MEL, NSW, PERTH 09507973 ); 7.6 km E on Mt Adams Road from Brand Highway , S of Dongara , 18 Aug. 2020, K. A. Shepherd & C. F . Wilkins KS 1719 ( CANB, MEL, NSW, PERTH 09507981 ); 800 m E on Gorges Road from the Ajana–Kalbarri Road, E of Kalbarri, 21 Aug. 2020, K. A. Shepherd & C. F . Wilkins KS 1738 ( CANB, MEL, NSW, PERTH 09507922 ) .

Figures

Fig. 1. (Caption on next page)

Fig. 14. Geleznowia uberiflora: (a) habitat; (b) habit, highlighting the prolific flowers observed in some plants; (c) solitary flower before anthesis, subtended by a few pale yellow bracts tinged with green at the apex; (d) side view of flowers showing the ovate green leaves and the young yellowish-green branchlet (red arrow); (e) flower beginning to open, showing the large obovoid stigma (red arrow); (f) open flower showing the large pale yellow sepals hiding the bracts below, and the bright yellow elliptic petals. Vouchers: A.D. Crawford ADC 1839 (b, c); K.A. Shepherd & B.M. Anderson KS 1828 (d, f); K.A. Shepherd & B.M. Anderson KS 1824 (e). Photos: A. D. Crawford (b, c); K. A. Shepherd (a, d–f).

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).