Abstract Detail

Ecology

Diaz, Nicolas [1], Cantley, Jason [1], Walsh, Seana [2], Martine, Chris [1].

Using ecological niche models to inform delimitation of cryptic species in Hawaiian Coprosma foliosa Complex (Rubiaceae).

The taxonomy among Coprosma spp. (Rubiaceae) in the Hawaiian Islands is complex, making it difficult to properly identify taxa in the field or even with herbarium specimens. Of particular confusion are taxa of the Coprosma foliosa Complex, which currently includes four recognized species and many synonymized taxa. As currently recognized, the complex consists of C. menziesii on Hawai‘i Island, C. stephanocarpa and C. cordicarpa on Maui, and the widespread taxon C. foliosa on Kaua‘i, Lana‘i, Moloka‘i, and O‘ahu. Taxa of the C. foliosa Complex occur in both native and non-native dominated mesic forests and represent the lowest elevation distribution of the genus in the archipelago. Their form varies from upright trees to lianas >15 meters in length. A recent excursion in March 2016 helped elucidate morphological and geographic differences garnered from morphometric analyses and field observations for two new taxa segregated from the C. foliosa Complex. These analyses are augmented by comparing environmental niche models among species within the Complex. Effectively, these taxa replace C. foliosa on the islands on Moloka‘i and Kaua‘i. The taxon from Moloka‘i is consistently a stout tree to over 10 meters in height, and most conspicuously differs in having two different sized seeds per fruit, earning it a tentative name of C. sp. ‘asymmetrisperma’. Asymmetry is also reflected in asymmetrical fruits. The fruit apex is the result of the largest seed bulging farther than the persistent calyx, shifting the calyx slightly off-center. The newly understood Kaua‘i taxon, tentatively named C. sp. ‘longipedicellata,’ is different from other taxa in the Complex in being a many-stemmed shrubby liana. In addition, flowers and fruits occur on considerably long pedicels/peduncles, leaves are more pubescent, and stipule morphology differs slightly compared to other members of the Complex. Hybrids are thought to occur for both taxa on their respective islands, C. sp. ‘asymmetrisperma’ with C. pubens on Moloka‘i and C. sp. ‘longipedicellata’ with C. waimeae on Kaua‘i.

1 - Bucknell University, Biology, 1 Dent Drive, Lewisburg, PA, 17837, USA
2 - National Tropical Botanical Garden, Science and Conservation, 3530 Papalina Road, Kalaheo, Hawaii, 96741, United States

Keywords:
Coprosma
Coprosma foliosa Complex 
Rubiaceae
Moloka‘i
Kaua‘i
Hawaiian Islands
pilo
undergraduate research
Niche modeling.

Presentation Type: Poster
Session: P, Ecology Section Posters
Location: Exhibit Hall/Savannah International Trade and Convention Center
Date: Monday, August 1st, 2016
Time: 5:30 PM This poster will be presented at 6:15 pm. The Poster Session runs from 5:30 pm to 7:00 pm. Posters with odd poster numbers are presented at 5:30 pm, and posters with even poster numbers are presented at 6:15 pm.
Number: PEC016
Abstract ID:396
Candidate for Awards:Ecological Section Best Undergraduate Presentation Award