Delissea Gaudich.

Delissea, along with Cyanea and Clermontia are the three baccate fruited Hawaiian lobeliad genera. These three genera can be difficult to tell apart as attested to by the number of mis-categorized species by experienced botanists. One trait specific to Delissea is the appearance of a knob, or gibbous, at the termination of the dorsal and sometimes lateral slits on the petals (see photos below).

Lammers (2005) split Delissea into three sections:

Species Section Flower length Island Status
Delissea rhytidosperma R1.4-2.4 cmK T&E
Delissea kauaiensis D1.6-3.0 cmK T&E (as subsp. of undulata)
Delissea argutidentataD1.6-2.4 cmH T&E (as undulata)
Delissea waianaeensis M4.5-6.2 cmO T&E (as subcordata)
Delissea undulata D2.2-2.4 cmM Extinct
Delissea niihauensis D2.2-2.5 cmN Extinct
Delissea parviflora R1.8-1.9 cmH Extinct
Delissea fallax R1.5-1.8 cmH Extinct
Delissea lauliiana R2.5-2.5 cmO Extinct
Delissea subcordata M4.5-6.0 cmO Extinct
Delissea laciniata M3.5-4.5 cmO Extinct
Delissea sinuata M3.7-3.7 cmO Extinct
Delissea fauriei M5.0-5.5 cmMoExtinct
Delissea lanaiensis M3.2-4.0 cmL Extinct
Delissea takeuchii M5.8-6.2 cmO Extinct

sect. Delissea

The four tree-like Delissea gathered into section Delissea have variously been considered varieties, subspecies and currently, under Lammers (2005), separate species. They differ in the following traits:

Trait D. undulata D. argutidentata D. kauaiensis D. niihauensis
IslandMauiHawai'iKaua'iNi'ihau
Leaf shapeOvate/LanceolateEllipticOvate/LanceolateOvate/Lanceolate
Leaf marginUndulate/SerrateSerrulateSerrate/CrenateSerrate/Crenate
Leaf size
Trait X

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