Didymium effusum var. tenue Lister, J. Bot.

Lado, Carlos & Basanta, Diana Wrigley De, 2018, Typification of the myxomycete taxa described by the Listers and preserved at the Natural History Museum, London (BM), Phytotaxa 341 (1), pp. 448-450 : 448-450

Didymium effusum var. tenue Lister, J. Bot. 35: 214. 1897

= Didymium anellus Morgan, J. Cincinnati Soc. Nat. Hist. 16(4): 148. 1894

— Lectotypus (designated here): UNITED KINGDOM. England, Essex, Wanstead Park , 51.5676ºN 0.0403ºE, 15 Sep 1896, G. Lister ( BM 1716 !, BM001089744 ) . Syntypus: UNITED KINGDOM. England, Essex, Wanstead Park , 51.5676ºN 0.0403ºE, 15 Sep 1896, G. Lister ( BM 1719 !, BM001095134 ) . Syntypus: UNITED KINGDOM. England, Essex, Wanstead Park , 51.5676ºN 0.0403ºE, 15 Sep 1896, G. Lister ( BM 2060 !, BM001095208 ) . Syntypus: UNITED KINGDOM. England, Essex, Wanstead Park , 51.5676ºN 0.0403ºE, 7 Sep 1896, (one slide, BM s.n.!, 1, BM001095135 ) . Syntypus: UNITED KINGDOM. England, Essex, Wanstead Park , 51.5676ºN 0.0403ºE, 12 Sep 1896, (one slide, BM s.n.!, 1 x, BM001095137 ) . Syntypus: UNITED KINGDOM. England, Essex, Wanstead Park , 51.5676ºN 0.0403ºE, Oct 1896, (one slide, BM s.n.!, 2, BM001095136 ) .

[BM] 1716 ( Didymium effusum Link / var tenue Lister )/ D. anellus Morgan / Wanstead Park 15.9.96/ G.L./ J. of Bot. June’ 97 p. 214. (Lister coll./ Mycetozoa./ Recd. 1898.)/ BM001089744. [BM] 1719 / Didymium anellus Morg. / var. tenue / depressed plasmodiocarp/ Wanstead/ Sep. 15.96 N.XIp132/ BM001095134. BM 2060 / Didymium anellus Morgan / (= D. effusum Link , var tenue Lister in Journ./ Bot. 1894, p. 214)/ Wanstead Park, Essex,/ 15.9.96/ Lister leg./ BM001095208 [label dated 2 JAN. 1909)]. BM s.n. one slide 1/ Didymium anellus Morg. / slender plasmodicr./ Wanstead Park 7.9.96/ NXI.p 132/ BM001095135. BM s.n. one slide 1 x / Didymium / anellus Morg. / spores 10 μ dark/ Wanstead Pk. 12.9.96/ NXI.p 132/ BM001095137. BM s.n. one slide 2/ Didymium / anellus/ Morgan/ Wanstead Park/ 10.96/ VXIp. 134/ BM001095136.

NOTES: Lister (1897: 214) commented “This form has appeared in extreme abundance among dead sycamore and

Spanish chestnut leaves in Wanstead Park, Essex, during last autumn. It is constant in its characters, and I first gathered it in the same locality in April, 1888 …”. There are 3 collections in BM from the same place and date (BM 1716, 1719,

2060). Of these we select BM 1716 as the most representative well preserved specimen and with a specific reference to the publication. Notebook XI: 132 has notes and drawings of “Box 1692” but we did not find this. Most of this material is corrected later by Lister to the current name D. anellus Morgan. There are three slides (1, 1 x and 2) identified as var.

tenue but with a paper with “ anellus ” stuck over the variety name . These are syntypes.