78 
THE CORAL TRIANGLE: HEARST BIODIVERSITY EXPEDITION 
Family Plexauridae Gray, 1859 
Genus Astrogorgia Verrill, 1868 
Astrogorgia spp. 
Figures 16-17 
Material Examined. — CASIZ 168899, Philippines, Calaniian Group, Busuanga Island, 
Coral Gardens Reef (11.98550°N, 120.07668°E), 14 m depth, 24 February 2010, coll. G. C. 
Williams, several partial colonies wet-preserved 95% ethanol; CASIZ 185465, Philippines, Luzon, 
Batangas Province, Maricaban Island, Bonito Island, 31.1 m depth, 16 May 2011, coll. G. C. 
Williams, 1 whole colony wet-preserved 95% ethanol; CASIZ 190428, Philippines, Kuzon, Batan¬ 
gas Province, Maricaban Isalnd, Devil’s Point, 15 m depth, 18 November 2012, coll. G C. 
Williams, one partial colony wet-preserved 95% ethanol. 
Remarks. — The branches are somewhat flattened with polyps usually placed oppositely in 
two longitudinal rows. 
The polyps are retractile into mound-like or cylindrical calyces. The prominent sclerites are 
robust spindles ornamented sparsely with mostly small tubercles. The color of the colonies is often 
red, magenta or purple, but orange, yellow, cream or tan are also recorded. 
Species. — Fifteen species are recognized (Appeltans et al. 2013). However, confusion in the 
literature regarding the definition of the genus has led to many taxa described in different genera, 
thereby making an actual determination difficult regarding the total number of species in the genus. 
Distribution.^ — Widely distributed in the Indo-Pacific: the Red Sea and western Indian 
Ocean to as far to the east as Tuvalu in the central Pacific. 
References. — Fabricius et al. (2007:91); Grasshoff and Bargibant (2001:164-175). 
Genus Echinogorgia Kolliker, 1865 
Echinogorgia sp. 
Figures 18B, 19 
Material Examined.— CASIZ 109537; Philippines, Luzon, Batangas Province, Caban 
Island, Kirby’s Rock; <31 depth; 22 April 1997; coll. G. C. Williams. 
Remarks. — Branching is planar and mostly lateral. Some branches may anastomose, but 
colonies only rarely form net-like fans. Branches are often thick and rounded at the terminal ends. 
The colonies do not hai'bor zooxanthellae. The color of colonies is often vivid red or orange, but 
can vary from brown to white or yellow; or they can also be bicolored. The polyps are completely 
retractile and often fonn conspicuous, mound-like or spiny calyces. This often gives the surface of 
the colonies a somewhat rough-to-the-touch texture. Characteristic sclerites of the calyces are 
thornscales with tuberculated root-like bases and usually thiee (or sometimes more) thom-like pro¬ 
jections at the opposite end. 
Species. — Thirty-six species are recognized (Appeltans et al. 2013), although a substantial 
amount of confusion appears in the literature regarding the differentiation of this genus with oth¬ 
ers such as Menella, Paraplexaura, and Echinomuncea. 
Distribution. — Widespread in the Indo-West Pacific: Madagascar, Red Sea, India, Sri 
Lanka, Thailand, Singapore, Taiwan, Australia, Indonesia, Philippines, New Guinea, New Caledo¬ 
nia, and Palau. 
References. — Fabricius and Alderslade (2001:202-205); Fabricius et al. (2007:91); 
Grasshoff and Bargibant (2001:187-190). 
