An optimum probability phylogenetic reconstruction considering GBlock-modified amino acid sequences regarding thirteen necessary protein-coding genetics getting 136 taxa (model: LG). The fresh phylogenetic status from Relicanthus daphneae was indicated having a reddish arrow. Node support is dependent on 1,100 bootstrap replicates (get a hold of embedded legend to have symbol incorporate) and forest is actually rooted on Placozoa. To own quality, acutely long twigs is actually shortened using hatch marks. Brands away from taxa throughout the forest noted which have asterisks were upgraded based on Viruses.
Bootstrap help for Relicanthus’ standing on the PhyML tree is actually 64.seven, which had been below a previously based cutoff, set on 70, to have a supported clade thirty-five . Since consequence of Rodriguez et al. cuatro necessary placement of Relicanthus in its very own genus and you will family relations separated from other actiniarians and you can an overview reclassification of the buy inside a few suborders, our analysis of complete mitogenome of Relicanthus put it cousin with the actiniarians.
Into the Anthozoa, we seen one to some of the conventional dating was in fact fixed but i along with retrieved unexpected relationships (Fig. 1): octocorals was in fact classified sibling so you’re able to medusozoans, and you may corallimorpharians were grouped cousin on the long/advanced scleractinians. Although not, both matchmaking was in fact retrieved when you look at the former knowledge 20,thirty six . As well, Porifera are resolved inside the Cnidaria, and you will cerianthids (illustrated by Ceriantheopsis americana) was basically aunt into Porifera + Hexacorallia.
The newest relationships among ocean anemones recovered in our forest about corresponded to the people retrieved by the Rodriguez et al. cuatro . We recovered monophyly of these two most recent actiniarian suborders (Anenthemonae and Enthemonae) and you can within Enthemonae, members of the three current superfamilies (Actinostoloidea, Actinioidea and Metridioidea) classified together, apart from Halcampoides purpureus. Among the enthemonaean superfamilies, Actinioidea grouped given that cousin so you can Actinostoloidea + Metridioidea, a relationship together with discover because of the Rodriguez ainsi que al. 4 , however, as long as considering mitochondrial family genes alone.
Our reevaluation of your cnidae from Relicanthus try centered on new terminology combining numerous classifications (come across Situation and methods), hence especially integrated ways to determine in more detail this new diversity off mastigophore nematocysts 37 . The brand new cnidae of Roentgen. daphneae are characterized by new longest spirocysts understood within hexacorals, basitrichs which have apical flaps, and you can mastigophore tablets equal to p-mastigophores Good, versus spines in the distal tubule (Fig. 2, Rodriguez et al. 4 ).
Undischarged nematocyst products flirt away from Relicanthus daphneae. (A) Basitrich; (B) p-mastigophore An effective (regarding actinopharynx); (C), detail of apex of a great basitrich demonstrating apical flaps (arrows). Measure pubs: A beneficial, B, C, 15 micrometers.
According to research by the mixture of molecular and you may morphological recommendations, we were in a position to place the in past times incerti ordinis Relicanthidae and you can its single known variety, Relicanthus daphneae, within the purchase Actiniaria. We designed for they yet another suborder, Helenmonae.
Suborder Helenmonae Daly and Rodriguez
Medical diagnosis. Actiniaria having better-set up pedal disk however, versus basilar looks. No marginal sphincter muscle mass. Longitudinal ectodermal system within the column. Deciduous, firmly tapered tentacles, for every single that have sphincter on foot. Twenty-four sets from best mesenteries setup hexamerously. Human body out of mesenteries weakened. Cnidom: Gracile spirocysts, basitrichs (that have apical flaps), and you may p-mastigophores A beneficial.
Etymology. The name is in prize of the Helen Fellowship program at the new American Museum away from Pure History, merging they into Latin keyword to possess anemone. The fresh Helen Fellowship, funded of the Helen Gurley Brownish Revocable Believe, prompts ladies to pursue work when you look at the computational research.
Remarks. Regardless if molecular data don’t firmly keep the affiliation regarding the taxon within the Actiniaria, the inner structure and you will ultrastructure of its nematocysts (basitrichs with apical flaps and you will p-mastigophores A without spines regarding the distal tubule) highly recommend this belongs into the Actiniaria.
Discussion
Mitochondrial gene order has been shown to effectively supplement phylogenetic analyses in determining evolutionary relationships 27 . The gene order in Relicanthus is the common order for anemone mitogenomes (with one exception: Alicia sansibarensis; Foox et al. 25 ). Based on a maximum composite likelihood analysis (see Supplementary Table S4) of Relicanthus with other actiniarians and a one-way ANOVA test of two groups (i.e. genetic distances between Relicanthus and actiniarians versus those between actiniarians; see Materials and Methods), there is a statistically significant difference (F(1, 56) = 7, p < 0.05; see Supplementary Table S5) between Relicanthus and all other actiniarians in terms of the sequence within the mitogenome. Thus, we do not classify Relicanthus within either of the two existing actiniarian suborders, but instead establish a new suborder (Helenmonae) of actiniarians containing Relicanthus alone. More specifically, Relicanthus represents an early-diverging group of anemones without any currently known congenerics; this could explain its relatively slow rate of molecular evolution compared to other actiniarians.