Unruhdinium Gottschling, 2017

Gottschling, Marc, Čalasan, Anže Žerdoner, Kretschmann, Juliane & Gu, Haifeng, 2017, Two new generic names for dinophytes harbouring a diatom as an endosymbiont, Blixaea and Unruhdinium (Kryptoperidiniaceae, Peridiniales), Phytotaxa 306 (4), pp. 296-300 : 297-298

Unruhdinium Gottschling , gen. nov. — Type: Unruhdinium jiulongense (H.Gu) Gottschling , comb. nov.

Description:—Thecate, phototrophic, free-living, primarily freshwater dinophytes usually harbouring a Cyclotella -like diatom as endosymbiont, which is separated from the host by a single unit membrane. Kofoidian plate formula with maximally ten epithecal plates (including 6’’) and 5c, 5’’’, 2’’’’, apical pore complex present. Plate surface smooth through granulate though never ornamented by a network of minute ridges, hypotheca with a varying number of more or less distinctive spines. Chloroplasts numerous and belonging to the endosymbiotic alga; eyespot surrounded by three membranes.

Etymology:—The name honours Andrew Chudy (*1957, a.k.a. N.U.Unruh), who is musician, experimental percussionist and instruments inventor. He is best known for his work with the Berlin music group Einstürzende Neubauten, of which he also is a founder.

Unruhdinium , gen. nov., currently comprise 5–10 species with the presence of Cyclotella -like diatoms as endosymbionts and a reduced number of epithecal plates as diagnostic traits. The general plate formula of the epitheca should be 4’ 0a 6’’ ( Bourrelly 1968, Zhang et al. 2011), but Unruhdinium jiulongense , comb. nov., and Unruhdinium minimum , comb. nov., are described as having 3’ 1a 6’’ ( Zhang et al. 2014, You et al. 2015). This inconsistency makes it difficult to separate the entirety of Unruhdinium from Peridiniopsis (under which many of its constituent species were initially described) likewise having 3’ 1a 6’’ ( Calado & Moestrup 2002), although both taxa are only distantly related in molecular phylogenetics ( Gottschling et al. 2017). Nevertheless, the differing number of cingular plates (6c in Peridiniopsis versus 5c in Unruhdinium , gen. nov.), the presence of longer through shorter spines on the hypotheca in Unruhdinium , gen. nov. (absent in Peridiniopsis borgei ), and the cell surface (never ornamented by a network of ridges in Unruhdinium , gen. nov., but in P. borgei ) may further argue for the uniqueness of Unruhdinium , gen. nov.

In molecular phylogenetics, Unruhdinium , gen. nov., is distinct from all Kryptoperidiniaceae , of which DNA sequence data are available ( Liu et al. 2008, Takano et al. 2008, Zhang et al. 2011, 2014, You et al. 2015, Yamada et al. in press, Kretschmann et al. unpubl.), and it does not show any filamentous or palmelloid growth as Dinothrix ( Pascher 1927) , of which no DNA sequence data are available at present. It is one of the two freshwater lineages identified in the Kryptoperidiniaceae , and it differs from Durinskia oculata , which has a regular formula of 4’ 2a 6’’ in the conformation of the epitheca (Kretschmann et al. unpubl.). The endosymbiont’s nucleus could not be confirmed yet for Unruhdinium niei , comb. nov., in light microscopy ( Liu et al. 2008), but the numerous chloroplasts are being also part of, and therefore evidence for, the engulfed alga. Its presence also in this species is further corroborated by sequencing of endosymbiont loci ( Zhang et al. 2014).

Unruhdinium jiulongense (H.Gu) Gottschling , comb. nov., basionym: Peridiniopsis jiulongensis H.Gu in X.You, Z.Luo, Y.Su, L.Gu & H.Gu, Nova Hedwigia 101: 316–318, figs 1–3. 2015.— Type: People’s Republic of China. Fujian, Zhangzhou, Jiulongjiang River, Xipi reservoir (December, 2012).

Unruhdinium kevei (Grigorszky & Vagas) Gottschling , comb. nov., basionym: Peridinopsis kevei Grigorszky & Vagas in Grigorszky, Vagas, Borics, Klee, Ant.Schmidt & Borbély, Acta Botanica Hungaria 43: 168–172, figs 2–21. 2001.— Type: Hungary. Jász-Nagykun-Szolnok, Mezőtúr, Peresi Holt-Körös (collection date unknown).

Unruhdinium minimum (Qi Zhang, G.X.Liu & Z.Y.Hu) Gottschling , comb. nov., basionym: Peridiniopsis minima Qi Zhang, G.X.Liu & Z.Y.Hu, Algological Studies 145/146: 122, figs 1–3. 2014.— Type: People’s Republic of China. Fujian, Zhangzhou, Jiulongjiang River (August, 2011).

Unruhdinium niei (G.X.Liu & Z.Y.Hu) Gottschling , comb. nov., basionym: Peridiniopsis niei, G.X.Liu & Z.Y.Hu , Nova Hedwigia 87: 490–496, figs 3–6. 2008.— Type: People’s Republic of China. Hubei, Wuhan, East Lake (Donghu) (March 18, 2004).

Unruhdinium penardii (Lemmerm.) Gottschling , comb. nov., basionym: Glenodinium penardii Lemmerm., Hedwigia 39 Beiblatt: 117. 1900. Peridiniopsis penardii (Lemmerm.) Bourr., Protistologica 4: 9. 1968.— Type: Swiss Confederation. Geneva, Lake Geneva (collection date unknown). Note: Lemmermann (1910) used the same epithet for a new species of Peridinium and included the name Glenodinium penardii in his taxonomic header. Thus, it remains unclear whether Lemmermann (1910) considered it as distinct from the present species (then, it was not validly published because of ICN Art. 52.1.), or a combination of it (then, the indicated ‘spec. nov.’ is confusing). Anyhow, the combination of Lindemann (1925) back to Glenodinium is not validly published.

Unruhdinium penardii var. robustum (Qi Zhang, G.X.Liu & Z.Y.Hu) Gottschling , comb. nov., basionym: Peridiniopsis penardii var. robusta Qi Zhang, G.X.Liu & Z.Y.Hu , European Journal of Protistology 47: 151, figs 2–3, 4C. 2011.— Type: People’s Republic of China. Yunnan, Manwan, Luodi River (Apr, 2008).

There is some connection between the productivity of the Berlin music group Einstürzende Neubauten and the promotion of issues in natural science (‘Newtons Gravitätlichkeit’, ‘Total eclipse of the sun’), biology (‘DNS Wasserturm’) and also botany (‘Blume’, ‘In the garden’, ‘Sag’ mir, ‘wo die Blumen sind’). However, our present choice for new generic names in the dinophytes may stimulate a discussion about the contemporariness and usefulness of Recommendation 20A (h) in the International Code of Nomenclature for algae, fungi, and plants not to ‘dedicate genera to persons quite unconnected with botany, mycology, phycology, or natural science in general.’ Historically, the recommendation goes back to the Vienna Rules at the beginning of the 20 th century when (phanerogam) botanists may have considered themselves rather at the end of the biodiversity assessment in terms of taxa at the generic level. We are aware today, however, that myriads of lineages remain to be named, particularly in the microbial world of algae and fungi, arguing against an unnecessary limitation and for a more liberal and open-minded application of The Code in this respect. This would be in tradition of, for example, Linné (1753), who dedicated many of his plant names to mythological figures, and has been recently readopted with naming the fern Gaga dedicated to one of the contemporary heroes ( Li et al. 2012). The approach has also found broad application in zoology and thus, our proposal comes as a small but perceivable step forward towards the harmonisation (if not even unification) of The Codes, being an important motivational drive for the work on such ambiregnal protists as the dinophytes.