Geniostoma imadae (Loganiaceae), a new single-island endemic species from Kaua‘i, Hawaiian Islands Author Wood, Kenneth R. 0000-0001-6446-1154 National Tropical Botanical Garden, 3530 Papalina Road, Kalāheo, HI 96741, USA Author Lorence, David H. 0000-0002-6735-9531 National Tropical Botanical Garden, 3530 Papalina Road, Kalāheo, HI 96741, USA Author Wagner, Warren L. 0000-0001-5012-8422 Department of Botany, Smithsonian Institution, PO Box 37012, Washington, DC 20013 - 7012, USA Author Fawcett, Susan 0000-0001-5021-1779 National Tropical Botanical Garden, 3530 Papalina Road, Kalāheo, HI 96741, USA & University and Jepson Herbaria, 1001 Valley Life Sciences Building # 2465, University of California, Berkeley, California 94720 - 2465, USA text PhytoKeys 2025 2025-06-10 257 191 207 journal article 310383 10.3897/phytokeys.257.154236 9e98280d-9b0d-4ddf-b847-e0586e63b269

Table 2. Comparison of morphological characters for species of Hawaiian Geniostoma having peduncles > 7 mm long.

	Geniostoma subg. Labordia sect. Labordia		Geniostoma subg. Labordia sect. Darbolia
Species	G. imadae	G. cyrtandrae	G. helleri	G. kaalae	G. lorencianum	G. tinifolium	G. triflorum
Pubescence on stems	glabrous	short-hispidulous	glabrous	short-hispidulous	tomentose	glabrous	glabrous
Pubescence on lower leaves	glabrous	short-hispidulous	glabrous	short-hispidulous	tomentose	glabrous	glabrous
Leaf base	cuneate to acuminate	cuneate	cuneate	cordate to truncate	cordate to auriculate	cuneate	cordate
Stipule length	4–8 (– 11) mm	3–7 mm	1–5 mm	1.5–2.4 mm	1.5–2 mm	1–4 mm	1–4 mm
Stipule pubescence	glabrous	margins ± ciliate	glabrous	margins ± ciliate	hirsute to tomentose	margins ± ciliate	margins ± ciliate
Peduncle length	20–75 mm	0–10 mm	5–20 mm	15–50 mm	20–60 mm	9–35 mm	40–80 mm
Capsule valves	transversely wrinkled	transversely wrinkled	longitudinally striate	transversely wrinkled	longitudinally striate	transversely wrinkled	transversely wrinkled
Corolla tube length	8–12 mm	15–22 mm	7–8 mm	9–10 mm	10–13 mm	5.5–7.8 mm	6–10 mm
Corolla lobe length	9–11 mm	8–13 mm	2–3.5 mm	2–3 mm	1.4–1.7 mm	1.7–2.3 mm	1.5–2.5 mm
Corolla color	orange-yellow	pale yellow	white or green-yellow	green or green-yellow	green	green-yellow	green-yellow
Corolla shape	salverform	salverform	urceolate	urceolate	urceolate	urceolate	urceolate