Hind Katharine R, Gabrielson Paul W, P Jensen Cassandra, Martone Patrick T
Department of Botany and Beaty Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada, V6T 1Z4.
Biology Department and Herbarium, University of North Carolina, Chapel Hill, Coker Hall CB 3280, Chapel Hill, North Carolina, 27599-3280, USA.
J Phycol. 2016 Dec;52(6):929-941. doi: 10.1111/jpy.12449. Epub 2016 Sep 15.
Molecular phylogenetic analyses of 18S rDNA (SSU) gene sequences confirm the placement of Crusticorallina gen. nov. in Corallinoideae, the first nongeniculate genus in an otherwise geniculate subfamily. Crusticorallina is distinguished from all other coralline genera by the following suite of morpho-anatomical characters: (i) sunken, uniporate gametangial and bi/tetrasporangial conceptacles, (ii) cells linked by cell fusions, not secondary pit connections, (iii) an epithallus of 1 or 2 cell layers, (iv) a hypothallus that occupies 50% or more of the total thallus thickness, (v) elongate meristematic cells, and (vi) trichocytes absent. Four species are recognized based on rbcL, psbA and COI-5P sequences, C. painei sp. nov., the generitype, C. adhaerens sp. nov., C. nootkana sp. nov. and C. muricata comb. nov., previously known as Pseudolithophyllum muricatum. Type material of Lithophyllum muricatum, basionym of C. muricata, in TRH comprises at least two taxa, and therefore we accept the previously designated lectotype specimen in UC that we sequenced to confirm its identity. Crusticorallina species are very difficult to distinguish using morpho-anatomical and/or habitat characters, although at specific sites, some species may be distinguished by a combination of morpho-anatomy, habitat and biogeography. The Northeast Pacific now boasts six coralline endemic genera, far more than any other region of the world.
对18S rDNA（小亚基）基因序列进行的分子系统发育分析证实了新属Crusticorallina在珊瑚藻亚科中的分类地位，它是该亚科中首个非节状的属，而该亚科的其他属均为节状。Crusticorallina与所有其他珊瑚藻属的区别在于以下一系列形态解剖特征：（i）凹陷的、单孔的配子囊和双/四分孢子囊概念体；（ii）细胞通过细胞融合相连，而非次生纹孔连接；（iii）上皮层为1或2个细胞层；（iv）下皮层占藻体总厚度的50%或更多；（v）伸长的分生细胞；（vi）无毛细胞。基于rbcL、psbA和COI-5P序列鉴定出四个物种，即模式种C. painei sp. nov.、C. adhaerens sp. nov.、C. nootkana sp. nov.和C. muricata comb. nov.（以前称为Pseudolithophyllum muricatum）。C. muricata的基原异名Lithophyllum muricatum保存在TRH的模式材料中至少包含两个分类单元，因此我们接受之前在UC指定的选型标本，我们对其进行了测序以确认其身份。尽管在特定地点，一些物种可能通过形态解剖、栖息地和生物地理学的组合来区分，但仅使用形态解剖和/或栖息地特征很难区分Crusticorallina属的物种。东北太平洋现在拥有六个珊瑚藻特有属，远远超过世界上的任何其他地区。
