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Clermontia kakena, Maui

Clermontia kakena, Maui

The DNA Barcoding Project at the University of Hawai‘ i at Hilo (funded by the Gordon and Betty Moore Foundation) involves examination of DNA sequence data of plant genera Clermontia and Cyrtandra on Hawai‘i Island and neighboring islands to establish the parameters under which the DNA Barcoding method succeeds as a system of species identification for recently derived (young) species.  The project is unique in its coupling of low-impact tissue sampling and the latest technology (454 pyrosequencing) in DNA sequencing for the purpose of identifying species-diagnostic genetic markers.  The 454 approach will allow unprecedented access to hundreds of thousands of DNA bases, from which variation useful for delineating populations, species, and inter-specific hybrids will be revealed.  Prior attempts to identify species-diagnostic molecular markers for Hawaiian plant taxa have used the traditional DNA sequences such as plastid genes or ribosomal DNA which involve a small number of loci and generally reveal too little variation to be useful for species delineation.  The DNA Barcoding Project aims to include all extant Hawaiian Clermontia and Cyrtandra species. Populations representing species geographic ranges are being sampled; this includes DNA/RNA tissue collection and collection of detailed vegetative and reproductive measurements.  Genetic diversity will be correlated with morphology and distribution. 

Ōhā wai in ‘Ōhi‘a lehua, Hawaii Island

Ōhā wai in ‘ōhi‘a lehua, Hawaii Island

Clermontia (Campanulaceae) is a member of the species-rich endemic Hawaiian lobeliads. This clade posesses 126 species derived from a single colonists making this the largest plant radiation in Hawaii.  Clermontia is comprised of of 22 species and 14 subspecies. Commonly known as ‘ōhā wai, Clermontia are found on all the main Hawaiian Islands except Kaho‘olawe.  Clermontia are small trees to shrubs that occupy montane bogs and the understory of montane wet and mesic forests; they are often found growing epiphytically on the dominant forest tree, ‘ōhi‘a lehua. Many ‘ōhā wai are vegetatively indiscernible; in the absence of reproductive parts identification is nearly impossible. However, ‘ōhā wai flowers are among the showiest of the native Hawaiian plants, this serves them well them in attracting bird pollinators. The deep curved ‘ōhā wai corollas are believed to have co-evolved with the native Hawaiian honeycreepers whose bills are perfectly shaped to reach the nectar deep in the corolla, during feeding endeavors pollen is deposited on the top of the birds head ready to be transported to the next receptive stigma.  Loss of pollinators and habitat has caused the decline of some ‘ōhā wai.  Of the 30 taxa, nine are federally listed as endangered (three of which have fewer than 50 known wild individuals); one is presumed extinct.  We have nearly 200 pictures of 16 species of ‘ōhā wai here.

Cyrtandra tintinnabula, Hawaii Island

Cyrtandra tintinnabula, Hawaii Island

Cyrtandra (Gesneriaceae, African violet family) is a genus of ~600 species that range from SE Asia to Australia to the Oceanic Islands of the Pacific, where it is extremely common and diverse.  Hawai‘i is home to 59 recognized species commonly known as ha‘iwale.  These fleshy subshrubs, shrubs and treelets are found on all the main islands except Kaho‘olawe in the understory of wet and mesic forests, often in gulches, steep slopes and sometimes cliff faces.  Although Cyrtandra species usually have very limited geographic ranges (i.e. restricted to a small gulch or mountain) the group is characterized by extreme polymorphism making species delimitation very difficult.  Frequent hybridization among sympatric species further compounds the matter. Cyrtandra are vulnerable to the damaging effects of non-native, feral ungulates (pigs, etc.) in the forests.  Of the 61 Hawaiian taxa, 22 are endangered; 10 of which have fewer than 50 known wild individuals.  We more than 500 pictures of over 30 species of ha‘iwale here.

Resolution of species’ boundaries will provide valuable information for the conservation of endangered species. In the past, continuous forest likely facilitated gene flow between what are now isolated populations due to habitat fragmentation and degradation.  However, this assumption often remains ambiguous and halts recovery actions.  By sampling individuals representing species’ geographic ranges, determining relatedness of disjunct populations will be possible.  The analyses proposed will discern the degree to which these populations are genetically isolated from each other (i.e., through recent common ancestry or recent/current gene flow).