Diplaziopsidaceae X.C.Zhang & Christenh., 2011

Christenhusz, Maarten J. M., Zhang, Xian-Chun & Schneider, Harald, 2011, A linear sequence of extant families and genera of lycophytes and ferns, Phytotaxa 19 (1), pp. 7-54 : 15-16

Family 34. Diplaziopsidaceae X.C.Zhang & Christenh. , fam. nov.

3 genera ( Diplaziopsis (type of the family), Hemidictyum , Homalosorus ).

Filices mediocres vel grandes; rhizomatibus crassis, erectis vel decumbentibus; laminis 1-pinnatis, imparipinnatis,

pinnis integris, glabris; venis lateralibus utroque costulae latere discretis sed margines versus reticulatim

anastomosantibus, areolarum 2–4 series facientibus, sine venulis discretis inclusis; soris secus venas longas prope

costulam elongatis, indusio similiter elongato membranaceo obtectis; indusiis plerumque 3–8 mm, interdum ad 1–2

cm longis, arcuatis, allantoideis; numero basico chromosomatum x=31, 40, 41. Genus quod est typus familiae:

Diplaziopsis C.Chr.

Description: Medium or large ferns, usually in forests near or by streams. Rhizomes decumbent to erect, thick; lamina 1-pinnate, imparipinnate, with pinnae entire, glabrous; veins free on either side of the midrib, but fully anastomosing toward the margins where they form 2 – 4 rows of areoles, without included free veinlets; sori elongate along the long veins close to the midrib, covered by a similarly elongates, membranous indusium; indusia usually 3 – 8 mm, sometimes up to 1 – 2 cm long, arched, sausage-like; spores with wing-like fimbriate and echinate folds, or low perforate plain folds. X=41, 40 or 31.

Notes:— Homalosorus pycnocarpos (Spreng.) Pic.Serm. has been transferred to Diplaziopsis by Price (1990). Different from the Asian Diplaziopsis with x=41, the temperate North American Homalosorus pycnocarpos has x=40 and the tropical American genus Hemidictyum marginatum with x=31. Hemidictyum was first shown to be sister to the Aspleniaceae by Schuetpelz & Pryer (2007), but no Diplaziopsis was included in their study. Here, we incorporate new evidence generated in the laboratory of X.-C. Zhang , and place these genera in one family ( Wei et al. 2010). The inclusion of Hemidictyum in Diplaziopsidaceae is however still tentative; further studies will have to confirm its placement.

Family 35. Thelypteridaceae Pic.Serm. , Webbia 24: 709 (1970).

5 or more genera

References: Smith (1986), Smith & Cranfill (2002), Yatabe et al. (2002).

Note:—Five genera ( Cyclosorus , Macrothelypteris , Phegopteris , Pseudophegopteris , Thelypteris ) recognised by Smith (in Kramer & Green 1990) and several formally proposed genera were treated as subgenera in Cyclosorus and Thelypteris . The current understanding of the relationships within the family is limited and thus we employ a conservative approach with large genera concepts for species belonging to Cyclosorus and Thelypteris . Narrower genera concepts are discussed to be replaced these two large genera but the current evidence is insufficient to make final conclusions.

Family 36. Woodsiaceae Herter, Rev. Sudamer. Bot. 9: 14 (1949).

1–3 genera ( Cheilanthopsis , Hymenocystis , Woodsia ).

Notes:— Woodsiaceae formerly included Athyriaceae and Diplaziopsidaceae . The family is here defined in its narrowest sense, including only Woodsia and two very closely related genera that, pending further evidence, may have to be merged with Woodsia in the future.

The lineages of Athyriaceae , Cystopteridaceae , Diplaziopsidaceae and Rachidosoraceae are found consistently segregated in all analyses, independently of sampling. Despite the relationships among these groups is not always resolved these lineages cannot be united with other large lineages. They are therefore treated as separate families.