A Phylogeny of the Family Poritidae (Cnidaria, Scleractinia) Based on Molecular and Morphological Analyses

Abstract

The family Poritidae formerly included 6 genera: Alveopora, Goniopora, Machadoporites, Porites, Poritipora, and Stylaraea. Morphologically, the genera can be differentiated based on the number of tentacles, the number of septa and their arrangement, the length of the polyp column, and the diameter of the corallites. However, the phylogenetic relationships within and between the genera are unknown or contentious. On the one hand, Alveopora has been transferred to the Acroporidae recently because it was shown to be more closely related to this family than to the Poritidae by previous molecular studies. On the other hand, Goniopora is morphologically similar to 2 recently described genera, Machadoporites and Poritipora, particularly with regard to the number of septa (approximately 24), but they have not yet been investigated at the molecular level. In this study, we analyzed 93 samples from all 5 poritid genera and Alveopora using 2 genetic markers (the barcoding region of the mitochondrial COI and the ITS region of the nuclear rDNA) to investigate their phylogenetic relationships and to revise their taxonomy. The reconstructed molecular trees confirmed that Alveopora is genetically distant from all poritid genera but closely related to the family Acroporidae, whereas the other genera are genetically closely related. The molecular trees also revealed that Machadoporites and Poritipora were indistinguishable from Goniopora. However, Goniopora stutchburyi was genetically isolated from the other congeneric species and formed a sister group to Goniopora together with Porites and Stylaraea, thus suggesting that 24 septa could be an ancestral feature in the Poritidae. Based on these data, we move G. stutchburyi into a new genus, Bernardpora gen. nov., whereas Machadoporites and Poritipora are merged with Goniopora.

The New Systematics of Scleractinia: Integrating Molecular and Morphological Evidence

“…These include amplifications of the Pax-C intron (van Oppen et al 2001(van Oppen et al , 2004Márquez et al 2002;Richards et al 2008Richards et al , 2013, β-tubulin (Fukami et al 2004b;Stefani et al 2008a), ITS (Medina et al 1999;van Oppen et al 2000Diekmann et al 2001;Rodriguez-Lanetty and Hoegh-Guldberg 2002;Márquez et al 2003;Chen et al 2004;Vollmer and Palumbi 2004;Forsman et al 2005Forsman et al , 2006Forsman et al , 2009Forsman et al , 2010Forsman et al , 2015Wei et al 2006;Stefani et al 2011;Kitano et al 2013Kitano et al , 2014, and 28S rDNA Cuif et al 2003;Wolstenholme et al 2003). For regions that have not diverged considerably between paralogues, such as the ITS, mixed PCR products can be split into two dominant sequences based on phase reconstruction of forward and reverse chromatograms of distinct lengths (Flot and Tillier 2006;Flot et al 2006).…”

“…Authors remain split between concatenating markers to obtain hidden support (Huang et al 2011;Addamo et al 2012;Arrigoni et al 2012Arrigoni et al , 2014aBenzoni et al 2012b) and making separate estimations of gene trees (Benzoni et al , 2012aGittenberger et al 2011;Bongaerts et al 2013;Kitano et al 2013Kitano et al , 2014Huang et al 2014a;Arrigoni et al 2015). With more markers available for inferring phylogenies, combined analyses of multilocus data may be the way forward.…”

“…Like its new confamilials, Alveopora possesses synapticulothecal walls (Wallace 2012). Its exact phylogenetic placement is unstable to date, although evidence has pointed to a close relationship with Astreopora (Fukami et al 2008;Kitahara et al 2010bKitahara et al , 2014Huang and Roy 2015;Kitano et al 2014; Fig. 4.1).…”

“…Only recently was the first comprehensive revision of Poritidae published. Kitano et al (2014) analysed samples from all five poritid genera using COI and ITS to show that Porites was monophyletic, but Machadoporites and Poritipora cannot be distinguished from Goniopora and were thus synonymised. The authors also found that Goniopora stutchburyi was genetically isolated from its congenerics but was the only sister species of Stylaraea, and thus moved it into a new genus, Bernardpora.…”

Species delimitation in the coral genus Goniopora (Scleractinia, Poritidae) from the Saudi Arabian Red Sea

“…Meanwhile, Veron (2000) proposed that the in situ polyp morphology could be used as a key character for underwater species delimitation, leading to even further taxonomic confusion. Few molecular studies have been carried out in this group, limited primarily to assessing the phylogentic position of G. stokesi (Kitano et al, 2013) and the evolutionary placement of the genus within the Poritidae (Kitano et al, 2014). Therefore we still lack a first attempt of species delimitation in Goniopora.…”