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Tenua hystrix ssp. hystrix

Tenua hystrix ssp. hystrix

Autonym. Now redundant.
Holotype: Eisenack, 1958, pl.23, fig.1; Sarjeant, 1985, pl.10, fig.5; Sarjeant, 1992, fig.1
Locus typicus: N Germany
Stratum typicum: Aptian
Translation Eisenack, 1958: Sarjeant, 1985

Original diagnosis: Eisenack, 1958, p.410
A species of Tenua of 75-105 µm length and about 65-97 µm breadth. The spinelets are, on the same individual, mostly rather constant in length, varying however-from 2-10 µm length; they are at their tips either thickened in knoblike fashion or briefly branched; only rarely do the short, clublike branch-prongs show secondary division.

Emended diagnosis: Sarjeant, 1985, p.95
Proximate, lenticular cysts, penitabulate and consisting of autophragm only. Ambitus subpolygonal, of variable breadth, with a strong antapical outbulge to the left, and a faint antapical swelling to the right, of the sulcal region in some specimens, both swellings reduced in others: apex smoothly rounded. Peniplates outlined by single or double rows of very short solid spinelets, their length only around 1/15 of the central body cross-measurement. Spinelets distally oblate to capitate or bifid, with very short branches subparallel to the autoblast surface, symmetrical or (rarely) asymmetrical. Penitabulation ?", 6", 5c, 5""", 1p, 1"""", 1-?s. Archaeopyle apical (type tA): operculum typically free, rarely attached.
Dimensions: Holotype (in dorsoventral orientation): overall length (apex lacking) 86 µm, overall breadth 97 µm. Figured specimen (in slightly oblique lateral view): overall length (apex attached) 75 µm, overall breadth 66 µm. Range of dimensions (all orientations); overall length 56-105 µm, overall breadth 48-95 µm. Sixty specimens measured.

Supplemental description: Mao Shaozhi and Norris, 1988, p.33: Cyclonephelium hystrix
Cyst dorsoventrally flattened, truncated-circular to semicircular in shape with no apical plates, usually more or less asymmetrical. Wall surface covered with stout, rigid, and densely and uniformly distributed nontabular processes; expanded proximally and slightly expanded or capitate distally; usually 1 to 2 µm (rarely up to 5 µm) long, 0.5 to 2 µm wide. Archeopyle apical, type (tA).
Operculum usually detached; archeopyle suture zigzag with accessory sutures indicating six precingular plates.
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