Fungalpedia – Note 14 Coremiostelium

Coremiostelium S. Baldauf, S. Sheikh & Thulin

Index Fungorum number: IF553752

Dictyostelids, a group of cellular slime molds or social amoebae, are commonly found in a wide range of soils and play important ecological roles as predators of soil bacteria (Sheikh et al. 2018). Dictyostelids taxa were informally classified into eight distinct clades and three complex groups namely polycarpum, polycephalum and violaceum (Romeralo et al. 2011), however, this classification was in conflict with molecular evidence (Schaap et al. 2006, Romeralo et al. 2007). Sheikh et al. (2018) refined the taxonomy and proposed a new classification of dictyostelids based on the only marker available for most dictyostelids, SSU rDNA data. They proposed the polycephalum complex as a new genus Coremiostelium, which refers to Dictyosteliales genera incertae sedis. Coremiostelium species are characterized by colorless sorocarps with cellular stalks, the sorocarp stalks form a single column, diverging only terminally in morphology, and the spores are elliptic to reniform (Sheikh et al. 2018). Coremiostelium polycephalum is the only species of this genus. It has been reported in grasslands, forests, and even poorly vegetated sites worldwide (Sheikh et al. 2018, Liu et al. 2020).

Type species: Coremiostelium polycephalum (Raper) S. Baldauf, S. Sheikh, Thulin & Spiegel

Basionym: Dictyostelium polycephalum Raper

Fig 1. Coremiostelium polycephalum. A. Sorocarps and newly formed migrating pseudoplasmodia. B. Fruiting structure composed of 3 sorocarps. C. Spores. Redrawn by De-Ping Wei from Raper (1956) and Sheikh et al. (2018).


Liu P, Zhang S, Zou Y, Li Z, Stephenson SL, Li Y 2020 – Distribution and ecology of dictyostelids in China. Fungal Biology Reviews 34, 170–177.

Raper KB 1956 – Dictyostelium polycephalum n. sp.: a new cellular slime mould with coremiform fructifications. Microbiology 14, 716–732.

Romeralo M, Cavender JC, Landolt JC, Stephenson SL, Baldauf SL 2011 – An expanded phylogeny of social amoebas (Dictyostelia) shows increasing diversity and new morphological patterns. BMC Evolutionary Biology 11, 1–10.

Romeralo M, Escalante R, Sastre L, Lado C 2007 – Molecular systematics of dictyostelids: 5.8 S ribosomal DNA and internal transcribed spacer region analyses. Eukaryotic Cell 6, 110–116.

Schaap P, Winckler T, Nelson M, Álvares-Curto E, Elgie B, Hagiwara H, Cavender JC, Milano-Curto A, Rozen DE, Dingermann T, Mutzel R, Baldauf SL 2006 – Molecular phylogeny and evolution of morphology in the social amoebas. Science 314, 661–663.

Sheikh S, Thulin M, Cavender JC, Escalante R, Kawakami SI, Lado C, Landolt JC, Nanjundiah V, Queller DC, Strassmann JE, Spiegel FW, Stephenson SL, Vadell EM, Baldauf SL 2018 – A new classification of the dictyostelids. Protist 169, 1–28.

Entry by

Feng-Ming Yu, De-Ping Wei and Thatsanee Luangharn, Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai 57100, Thailand

(Edited by Chitrabhanu S. Bhunjun and Kevin D. Hyde)