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Pycnactis

Classification

    Phylum:  
Cnidaria
    Class:  
Anthozoa
    Subclass:  
Rugosa
    Order:  
Stauriida
    Suborder:  
Lykophyllina
    Family:  
Lykophyllidae
    Formal Genus Name and Reference:  
Pycnactis RYDER, 1926, p. 386
    Type Species:  
Hyppurites mitratus VON SCHLOTHEIM, 1820, p. 352; OD; tin SCHLOTHEIM Coil., HU, E. Berlin; lectotype by LANG, SMITH, & THOMAS, 1940, p. 112


Images

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Fig. 162,1. *p. mitratus (VON SCHLOTHEIM), God., Swed.; ext. view, X1 (Hisinger,1831).


Synonyms

Pycnactis


Geographic Distribution

Eu.(God.-U.K)


Age Range

    Beginning Stage in Treatise Usage:  
Sil.
    Beginning International Stage:  
Rhuddanian
    Fraction Up In Beginning Stage:  
0
    Beginning Date:  
443.07
    Ending Stage in Treatise Usage:  
Sil.
    Ending International Stage:  
Pridoli
    Fraction Up In Ending Stage:  
100
    Ending Date:  
419


Description

Solitary, curved trochoid, with oblique calice; major septa dilated and extending almost to axis; in early stages cardinal septum longer and thicker than others; minor septa very short, dilated; tabulae seldom seen due to dilatation of septa; rare dissepiments may occur in calice only. [Until lectotype is restudied and illustrated, generic name (senstl SMITH, 1945, p. 53) cannot be used with confidence.]




References

Smith, Stanley, , \& Lang, W. D., , \& Ryder, T. A., 1926, The genus Corwenia, gen. nov.: Ann. Mag. Nat. Hist., ser. 9, v. 17, p. 149-159, pl. 5, 6.


Museum or Author Information