Lomandra tenuis Jian Wang ter & B.Gray

Wang, Jian & Gray, Bruce, 2024, Two new species of Lomandra (Asparagaceae: Lomandroideae) from north Queensland, Australia, Phytotaxa 646 (3), pp. 293-300 : 296-299

Lomandra tenuis Jian Wang ter & B.Gray , sp. nov.

Type:— AUSTRALIA. Queensland: Cook District, 1km SW of Watsonville , 17.3825°S, 145.3072°E, 880 m, 24 February 2023, Gray 10114 (holotype: BRI!, isotypes: K!, MEL!).

Lomandra sp. Watsonville (BG 9948) ( Gunn et al. 2024).

Diagnosis:— Lomandra tenuis resembles L. grayi Jian Wang ter, but differs from the significantly narrower leaves; the acuminate leaf apex; the significantly longer female pedicel; the fewer male and female flowers ( Table 1 ).

Description:—Plants are tussocks with ascending rhizomes and rigid spreading roots, each tussock usually comprising 1 to 10 tufts (stems). Each tuft is 3–6 mm in diameter at the base with leaves arranged distichously or irregularly. Leaves firm and upright. Leaf sheath margins at first membranous or cartilaginous, fraying into short to long strips or fibres 4–8 cm long, white, pale brown, straw-coloured to reddish purple. Leaf blades yellowish green, glabrous, concavo-convex, flatten out towards the tips; with 3–9 parallel fine veins on each surface; margins smooth, rarely minutely scabrous; leaf apex usually obtuse to acute without teeth. Leaves of male and female plants are similar, 240–420 mm long, 0.2–0.7 mm wide. Male and female inflorescences similar in appearance being raceme or paniculate. Male inflorescence 1 per tuft, usually shorter than longest leaf; 120–270 mm long; scape flattened, smooth to minutely verruculose, 80–140 mm long, 0.5–0.8 mm wide, white, whitish brown or light purplish; primary rachis flattened, slightly angled, longitudinally ribbed, usually twisted, smooth to minutely verruculose, 80–120 mm long, 0.4–0.7 mm wide, same colour as scape, bearing 0–5 branches; branches alternately arranged along the rachis, 6–20 mm apart, flattened, angled, or channelled or longitudinally ribbed, usually twisted, smooth to minutely verruculose, 10–55 mm long, 0.2–0.4 mm wide, longest branch usually at base, shorter upwards. Each branch has a single bract, long- to short-deltoid, 1.5–3 mm long, 0.6–1 mm wide at the widest point, with single mid vein, longest usually at the basal node of rachis, shorter upwards along rachis, usually half encircling the branch. All flowers usually similar ages within each inflorescence. Male flowers usually 10–30(–40), solitary, alternate or very rarely appearing paired; each flower has a bract, cucullate, 0.5–2 mm long, 0.4–1 mm wide, membranous, usually half encircling the pedicel. Flower pedicels terete, flattened or angular, 1.5–4(–6) mm long, 0.15–0.2 mm wide, white to light greenish. Flower buds ellipsoid, light green. Male perianth segments 6 with distinct outer and inner whorls; outer tepals (sepals) 3, cucullate, free except on the very base, uniform in size, thick with slightly thin whitish margins in texture, 1.5–1.8 mm long, 1.1–1.3 mm wide, light green to light yellow; inner tepals (petals) 3, broadly cucullate, free except on the bottom portion, uniform in size, thick with slightly thin margins in texture, 1.6–1.8 mm long, 1.7–1.9 mm broad, cream to yellow except for whitish on the margins. Stamens 6, all adnate basally to a swollen centre surrounded by the inner tepals, 3 slightly higher, alternating with inner tepals and 3 slightly lower, alternating with outer tepals; filament 0.15–0.2 mm long, c. 0.15 mm diameter; anthers all similar, versatile, 0.4–0.5 mm long, 0.3–0.4 mm wide, bright yellow. Pistillode in the swollen centre c. 0.15 mm long and 0.15 mm diameter. Female inflorescence 1 per tuft, shorter than longest leaf; 100–210 mm long; scape flattened, smooth to minutely verruculose, 40–120 mm long, 0.4–0.8 mm wide, white, whitish brown or light purplish; primary rachis flattened, slightly angled, longitudinally ribbed, usually twisted, smooth to minutely verruculose, 20–55 mm long, 0.4–0.8 mm wide, whitish brown or purplish, bearing 0–3 branches; branches alternately arranged along the rachis, 6–16 mm apart, flattened, angled, or channelled or longitudinally ribbed, smooth to minutely verruculose, 6–11 mm long, 0.2–0.4 mm wide, longest branch usually at base, shorter upwards. Each branch has a single bract, long- to short-deltoid, 1.5–2.5 mm long, 0.6–1 mm wide at the widest point, with single mid vein, longest usually at the basal node of rachis, shorter upwards along rachis. All flowers usually similar ages within each inflorescence. Flowers 3–7(–11), solitary, alternate or very rarely appearing paired; each flower has a bract, cucullate, 1–1.5 mm long, 0.3–0.7 mm wide, membranous, usually half to ¾ encircling the pedicel. Flower pedicels terete, flattened or angular, 1–2 mm long, 0.15–0.2 mm wide, white to light greenish. Flower buds ellipsoid, green to greenish brown. Female perianth segments 6 with distinct outer and inner whorls, green to yellowish green; outer tepals (sepals) 3, cucullate, apex acute, free except on the very base, uniform in size, coriaceous with strongly raised mid vein, 1.7–2.2 mm long, 1.1–1.5 mm wide; inner tepals (petals) 3, broadly orbicular with a blunt apical extension, free except on the bottom portion, uniform in size, coriaceous with slightly thin margins in texture, 2.45–2.6 mm long, 2.3–2.5 mm wide. Staminodes inconspicuous or sometimes absent, when present lacking filaments and bearing vestigial anthers, 3 inserted on the middle part of inner tepals, 3 alternating with them on the middle of lower part of each inner tepal. Pistil conspicuous, styles c. 0.2 mm long by 0.2 mm wide, stigmatic lobes 3, c. 0.2 mm long; ovary usually sessile, triangular in cross section, c. 1 mm long by 1.2 mm diameter, with 3 locules; ovules 1 per loculus. Fruit pedicels 1–1.5 mm long, 0.3–0.4 mm wide. Fruiting styles c. 0.1 mm long, persistence. Capsules obovoid, usually 5.5–6.5 mm long, 5–6 mm diameter, brown to dark brown usually with irregular wrinkles; carpel brown to dark brown, light or pale brown inside; the carpel margins smooth; fruiting perianths, 6, coriaceous, persistent, bracts usually persistent. Seeds 1 per locule, but 1 or 2 developed, narrowly ovoid to ovoid, c. 3 mm long by 4.5 mm wide, usually flat on inner face, rounded on outer face, rough or slightly wrinkled, translucent in appearance, whiteish brown. ( Figure 2 )

Additional specimens examined:— AUSTRALIA. Queensland, Cook District: Watsonville Cemetery, cultivated at Hasties Rd , Atherton, 1 December 2017, Gray 9948 ( CNS) ; Watsonville Range, 7 February 2023, Gray 10097 ( BRI) ; Road opposite Watsonville Cemetery Rd, 8 February 2023, Gray 10098 ( BRI, CANB, CNS, NSW) ; 1km SW of Watsonville , 19 February 2023, Gray 10100 ( BRI) ; 1km SW of Watsonville , 20 February 2023, Gray 10102 ( BRI) .

Distribution and habitat:— Lomandra tenuis is endemic to northeast Queensland, where it is restricted to the west and south west of Herberton, and the Watsonville area where it is common ( Figure 3 ). Plants occur scattered in open forest and woodland dominated by Eucalyptus cloeziana F.Muell. , E. portuensis K.D.Hill , E. crebra F.Muell. , Corymbia citriodora (Hook.) K.D.Hill & L.A.S.Johnson subsp. citriodora , Callitris intratropica R.T.Baker & H.G.Sm. , and Allocasuarina inophloia (F.Muell. & F.M.Bailey) L.A.S.Johnson with sparse understory of grasses and sedges.

Phenology:—Male flowering was mainly recorded from December to February. Female flowering and fruiting were recorded in February.

Discussion:— Lomandra tenuis has the narrowest leaves among all known species in the genus. It belongs to the L. filiformis group of eastern Australia and is closely related to L. scabrifolia and L. grayi ( Gunn et al. 2024) . However, it is readily distinguished from the two, by its 0.5–0.8 mm leaf width (3–5 mm wide and 1.1–2 mm wide for L. grayi and L. scabrifolia respectively), the acuminate leaf apex (Obtuse, near rounded with minute teeth or without teeth for L. grayi and L. scabrifolia ); Fewer (3–7) female flowers (10–25 for L. grayi and L. scabrifolia ) and longer (1–2 mm long) female pedicel (0.3–0.6 mm long for L. grayi and L. scabrifolia ) ( Table 1 ).

Conservation status:— Lomandra tenuis can be a common species where it occurs. Although it is not recorded from a national park, it is not known to be at risk. Therefore, the category Least Concern (LC) is recommended using the IUCN (2019) criteria.

Etymology:—From the Latin tenuis , meaning slender. The epithet is in reference to the leaf blades which are the narrowest known in the genus.

Figures

FIGURE 2. Lomandra tenuis. A. Tufted plant. B. Leaf tips. C. Male flower. D. Female flower. E. Fruits. Photos by B. Gray.

FIGURE 3. Distribution map of Lomandra scabrifolia and L. tenuis.