Hymenophyllum iwatsukii

Name

Hymenophyllum iwatsukii

Rank

Species

Generic Name

[Genus] Hymenophyllum

Authors (Pub.)

Herrera F. Moran R. C. Shi G.-L. Ichinnorov N. Takahashi M. Crane P. R. Herendeen P. S.  

Publication

An exquisitely preserved filmy fern (Hymenophyllaceae) from the Early Cretaceous of Mongolia [2017/9]

Journal

American Journal of Botany

Volume

104

Issue

9

Page number

1371

Year

2017

Fossil Status

foliage (fertile)

Stratigraphy

Aptian

Strat. comment

Albian

Location

Tevshiin Govi and Tugrug coal mines, central Mongolia

Paleoregion

Eurasia (Central Asia)

Data for Holotypus

Repository

Field Museum, Chicago, USA

Repository Number

PP56496

Num

Figures 1I, 2A, 3A, 4A

Pub.

An exquisitely preserved filmy fern (Hymenophyllaceae) from the Early Cretaceous of Mongolia [2017/9]

Diagnosis

Fronds with circinate vernation. Pinnae pinnatifid with costae alate throughout. Pinnules alternate, weakly imbricate, and segmented. Venation of sterile pinnules anadromous and the pinnule margins serrate. Venation of fertile pinnules catadromous and the pinnule margins entire. Pinnules membranaceous (one cell-layer thick between the veins) and lacking stomata. Epidermis of lamina composed of jigsaw puzzle-like cells with prominently undulating anticlinal walls. Sori marginal, solitary, with up to 8 to 20 sori per pinna. Indusia bivalvate, funnel-shaped, and entire margined. Sporangia sessile to short-stalked. Receptacle nonprotruding, included within the indusial flaps. Sporangia circular, elliptical, to obovate in outline, at least 8–12 per sorus. Annulus complete and oblique. Spores trilete, tetrahedral, smooth to very finely papillate.