Melithaeidae Gray, 1870

Benayahu, Yehuda, Ofwegen, Leendert Pieter van, Dai, Chang-feng, Jeng, Ming-Shiou, Soong, Keryea, Shlagman, Alex, Du, Samuel W., Hong, Prudence, Imam, Nimrah H., Chung, Alice, Wu, Tiana & McFadden, Catherine S., 2018, Psammoecus simonis Grouvelle 1892, Zoological Studies 57 (50), pp. 1-26 : 12-13

Family Melithaeidae Gray, 1870

Melithaea Milne Edwards, 1857

Melithaea ochracea (Linnaeus, 1758)

Occurrence: ZMTAU Co 36922, Dongsha, (20°43.448'N; 116°42.520'E), 3-4 m, 13 June 2015.

Field notes: Rare.

Distribution in Taiwan: Southern Taiwan.

L-INS-i method in MAFFT ( Katoh et al. 2005) was used to align sequences to reference datasets consisting of previously published sequences for the relevant genera (e.g. McFadden et al. 2006 2009 2014; Benayahu et al. 2012). Pairwise measures of genetic distance (Kimura 2-parameter) among sequences were computed using MEGA v.5 ( Tamura et al. 2011). jModelTest2 ( Darriba et al. 2012) was used to select appropriate models of evolution for maximum likelihood ( ML) analyses that were run using GARLI 2.0 ( Zwickl 2006). Analyses were run using mtMutS alone ( Sinularia ), mtMutS concatenated with igr1 + COI (all taxa), and 28S rDNA alone [Cladiella, Klyxum , Nephtheidae , Xeniidae (for list of genera of these families see Table 1)]. Bayesian analyses used MrBayes v. 3.2.1 ( Ronquist et al. 2012) with the same evolutionary models as ML, run for 5,000,000 generations (or until standard deviation of split partitions <0.01) with a burn-in of 25% and default Metropolis coupling parameters.

Identification of characteristic attributes in

Sinularia

To resolve discrepancies between morphological vs. molecular species identifications in the speciose genus Sinularia , we identified sets of characteristic attributes within the mtMutS sequence to use as species-specific barcodes. All mtMutS sequences obtained for Sinularia were aligned and viewed using MacClade ( Maddison and Maddison 2005). Each nucleotide position within the 735 bp alignment was then categorized as invariant or variant, and variant positions were further scrutinized to identify pure characteristic attributes (simple PuCAs sensu Rach et al. 2008) of (1) clades and (2) species within clades. Cladespecific PuCAs occurred when all of the species belonging to a clade (clades 1-5 as defined in McFadden et al. 2009) shared the same nucleotide at a particular position within the mtMutS sequence and no species of any other clade shared that nucleotide identity. Species-specific PuCAs were defined as nucleotide positions at which all of the individuals of a morphospecies shared the same nucleotide at a particular position, and no other morphospecies belonging to that clade shared that nucleotide identity. Compound PuCAs consisting of unique combinations of nucleotide identities at more than one nucleotide position were also identified for some taxa that lacked diagnostic simple PuCAs. Considered together, the cladespecific and species-specific PuCAs represent a compound PuCA (i.e. a diagnostic character set) that can be used as a unique sequence barcode to identify most species of Sinularia unequivocally.