Zoological Studies

Vol. 50 No. 1, 2011

Latitudinal Gradient of Morphological Variations in Zebra Coral Oulastrea crispata (Scleractinia: Faviidae) in the West Pacific

Kao-Song Chen1,3, Hernyi Justin Hsieh3, Shashank Keshavmurthy1, Julia Ka Lai Leung1,4, I-Ting Lien5,6, Yoshikatsu Nakano7, Sakanan Plathong8, Hui Huang9, Chaolun Allen Chen1,2,10,*

1Biodiversity Research Center, Academia Sinica, Nangang, Taipei 115, Taiwan
2Institute of Oceanography, National Taiwan University, Taipei 106, Taiwan
3Fisheries Research Institute, Council of Agriculture, Executive Yuan, Keelung 200, Taiwan
4Department of Life Science, National Taiwan Normal University, Taipei 106, Taiwan
5Graduate School of Agriculture, Kyoto University, Kyoto 605-8502, Japan
6Field Science Education and Research Center, Kyoto University, Wakayama 649-2211, Japan
7Sesoko Station, Tropical Biosphere Research Center, University of Ryukyus, Okinawa 905-0227, Japan
8Department of Biology, Prince of Songkla University, Songkla 90112, Thailand
9South China Sea Institute of Oceanology, Chinese Academics of Science, Guangzhong 510301, China
10ARC Center of Excellence for Coral Reef Studies, James Cook University, Townsville Q4810, Australia

Kao-Song Chen, Hernyi Justin Hsieh, Shashank Keshavmurthy, Julia Ka Lai Leung, I-Ting Lien, Yoshikatsu Nakano, Sakanan Plathong, Hui Huang, Chaolun Allen Chen (2011) Corals grow across latitudes throughout the tropics and subtropics where environmental factors, including the average annual temperature and seasonal changes in water clarity and temperature, substantially vary. These environmental factors could lead to latitudinal variations in coral skeletal morphology. In this study, morphometric variations of the zebra coral Oulastrea crispata, a small coral species with black and white septa and a colony diameter usually < 10 cm, were investigated. Previous studies reported that O. crispata can survive in extreme environmental conditions, such as low temperatures and turbid water. One hundred colonies of O. crispata were collected from sites spanning Thailand to Japan, across tropical, subtropical, and temperate regions. Five micro-characters of corallites were measured and examined using univariate and multivariate analyses. All micro-characters measured significantly differed among latitudinal regions (nested ANOVA, p < 0.05). A canonical discriminant analysis (CDA) indicated that corallite diameter was the most important character contributing to variations in O. crispata among the 3 latitudinal regions, although a plot of the 1st and 2nd canonical variables showed that O. crispata from different latitudinal regions could not be fully separated. Nevertheless, significant differences in the Mahalanobis distances between the CDA group centroids were detected, suggesting a latitudinal gradient of morphological variations in O. crispata in the West Pacific.

Key words: Scleractinian, Morphometrics, Corallites, Oulastrea crispata, Latitudinal variation.

*Correspondence: E-mail:cac@gate.sinica.edu.tw