Lycianthes dendropilosa (Symon) A.R.Bean, Austrobaileya 6(3): 567. 2003.

Knapp, Sandra, 2022, A revision of Lycianthes (Solanaceae) in Australia, New Guinea, and the Pacific, PhytoKeys 209, pp. 1-134 : 1

6. Lycianthes dendropilosa (Symon) A.R.Bean, Austrobaileya 6(3): 567. 2003.

Figs 19 , 20

Solanum dendropilosum Symon, J. Adelaide Bot. Gard. 8: 44. 1985. Type. Papua New Guinea. Western Highlands: Laiagam, Lagaip valley, near Kepilam village, 2,439 m, 2 Aug 1960, R.D. Hoogland & R. Schodde 7291 (holotype: CANB [CANB83729]; isotypes: A [00395063], BM [BM000886135], BRI [BRI-AQ0080425], G [G00343297], L [L0003631], LAE [acc. # 39126], US [00479494, acc. # 2411884]).

Type.

Based on Solanum dendropilosum Symon.

Description.

Straggling shrubs or root climbers, 1-1.5 m tall; stems terete, densely glandular-papillate and densely pubescent with uniseriate dendritic trichomes to 0.75 mm long, the branches short and congested ( “tannenbaumartig” sensu Seithe 1962), these drying yellowish tan; new growth densely papillate and pubescent like the stems, the trichomes tangled and interwoven; bark of older stems pale brown, becoming somewhat corky and glabrescent. Sympodial units difoliate, the leaves geminate, the leaves of a pair differing in size and shape. Leaves simple; blades of major leaves 2.5-4 (8) cm long, 1-2.5 cm wide, elliptic to narrowly elliptic (lanceolate in Symon & Katik 10691), widest in the middle, discolorous, coriaceous or membranous (Symon & Katik 10691); adaxial surfaces shiny, sparsely and unevenly pubescent with dendritic trichomes with congested branches like those of the stems, these denser along the midrib and principal veins; abaxial surfaces densely dendritic pubescent (lamina barely visible in Hoogland & Schoode 7291), yellowish tan; principal veins 4-6 pairs, densely pubescent, the midrib keeled adaxially; base acute; margins entire, strongly revolute in Hoogland & Schoode 7291; apex acute or more often acuminate; petiole 0.4-0.6 cm long, densely dendritic-pubescent like the stems; blades of minor leaves 0.6-0.7 cm long, 0.6-0.7 cm wide, orbicular or heart-shaped, similar in texture and pubescence to the major leaves; base cordate or rounded; margins entire or revolute; apex rounded; petiole absent or less than 0.1 cm long, densely dendritic-pubescent. Inflorescences axillary fascicles of 1-3 flowers, only one open at a time, densely dendritic-pubescent; pedicels at anthesis 1-1.2 cm long, ca. 1 mm in diameter at the base, ca. 1.5 mm in diameter at the apex, erect or spreading, densely pubescent with golden dendritic trichomes with congested branches like those of the stems and leaves, articulated at the base; pedicel scars tightly packed in the leaf axils, Buds long-ellipsoid, the corolla strongly exserted from the calyx tube before anthesis. Flowers 5-merous, probably heterostylous and unisexual, no styles seen in the only flowering specimen seen (Hoogland & Schoode 7291), the plants possibly dioecious. Calyx tube ca. 3 mm long, 3-3.5 mm in diameter, cup-shaped, densely golden dendritic-pubescent with trichomes like those of the pedicels, thick and coriaceous (fleshy in live plants?), without appendages, the rim slightly thickened. Corolla 1.5-2 cm in diameter, purple (mauve), deeply stellate, lobed nearly to the base, interpetalar tissue absent, the lobes 6-9 mm long, 2-3 mm wide, spreading, thick and fleshy, adaxially glabrous, abaxially moderately pubescent with simple uniseriate trichomes 0.25-0.5 mm long, if these branched then merely forked, the branches not congested, the tips and margins densely papillate, the tips cucullate. Stamens equal; filament tube minute; free portion of the filaments 1-1.5 mm long, glabrous; anthers 5-7 mm long, 1-1.2 mm wide, long-ellipsoid and tapered at the tips, yellow, poricidal at the tips, the pores distally directed, not elongating with age. Ovary not seen. Fruit and seeds not known. Chromosome number not known.

Distribution

(Fig. 21 ). Lycianthes dendropilosa is endemic to New Guinea; it has only been collected in Papua New Guinea (Southern Highlands, Western).

Ecology and habitat.

Lycianthes dendropilosa has been collected in open areas near villages (Symon & Katik 10691 from "near old garden site"), from 2,400 to 2,700 m elevation.

Common names.

None recorded.

Preliminary conservation assessment

( IUCN 2020). EOO (0 km2 - CR); AOO (8 km2 - CR). Lycianthes dendropilosa is known from only two localities and has been very rarely collected. It could be assessed as Data Deficient (DD), but given the threats to New Guinea forests more broadly I suggest it warrants assessment as Critically Endangered (CR [B1,2a,b(iii,iv)]); more collecting and a better understanding of its distribution are priorities.

Discussion.

Lycianthes dendropilosa is a distinctive species with small leaves, branched trichomes with densely congested branches, and 1-3 flowers per leaf axil. It shares trichome type with L. bitteriana , but that species is a coarse herb rather than a straggling shrub, has many flowers on a short inflorescence axis rather than 1-3 flowers per axil, and smaller flowers with copious interpetalar tissue (1-1.2 cm in diameter with interpetalar tissue in L. bitteriana , 1.5-2 cm in diameter without interpetalar tissue in L. dendropilosa ). Fruits of L. dendropilosa are not yet known. Other than the type, that has thick, coriaceous leaves with somewhat revolute margins, the only other specimen I have seen that is attributable to this species (Symon & Katik 10691) is sterile; the leaves on this specimen are much thinner in texture and more elongate, indicating this may represent a juvenile pre-flowering individual.

Specimens examined.

Papua New Guinea. Southern Highlands: between Nol and Mendi, 24 km from Mendi , just after crest ["and o"], 2,000 m, 24 Jun 1977, Symon & Katik 10691 (L, LAE) .

Figures

Figure 19. Lycianthes dendropilosa (Symon) A. R. Bean. Drawing by M. L. Szent-Ivany, first published in Symon (1985: fig. 11, as S. dendropilosum Symon). Courtesy of the Board of the Botanic Gardens and State Herbarium (Adelaide, South Australia), reproduced with permission.

Figure 20. Lycianthes dendropilosa herbarium specimen. Papua New Guinea. Western Highlands: Hoogland & Schodde 7291 (isotype of S. dendropilosum, BM 000886135). Courtesy of the Trustees of the Natural History Museum, London, reproduced with permission.

Figure 21. Distribution of Lycianthes dendropilosa.