Pollicipes rigida

Jagt, John W. M., Zonova, Tatiana D. & Jagt-Yazykova, Elena A., 2007, A review of the brachylepadomorph cirripede genus Pycnolepas, including the first record of an Early Cretaceous species from the Russian Far East *, Zootaxa 1545, pp. 33-47 : 36

Pycnolepas rigida (J. de C. Sowerby, 1836)

Original description. J. de C. Sowerby (1836: 335, pl. 11, fig. 6, as Pollicipes rigidus ).

Type. Lectotype, designated by Withers (1914: 170), is a scutum illustrated by J. de C. Sowerby (1836); current whereabouts unknown.

Locality and stratigraphy. Folkestone, southeast England; lower Gault (middle Albian).

Remarks. Va l v e s o f P. rigida are transversely, and generally also longitudinally, ridged; scutum elongatetriangular, with basilateral portion produced and with narrow wall-sided ridge curving from apex to basilateral angle; tergum with apical portion much curved towards scutum and with ridge like that of scutum, curving from apex to basal angle; width of imbricating plates exceeding height. Lot NHMM 2006 0 20 (leg. J.S.H. Collins), comprising isolated scuta, terga, rostra and carinae from the Albian of Bedfordshire ( England), shows the wide range of variation of this taxon, expressed in valve proportions (length/width ratio), ornament (in particular, number and strength of longitudinal and transverse ribs) and width of apicobasal ridge (see Withers, 1935).

Occurrence. Lower Albian (c. 108–107 Ma) to middle (?upper) Cenomanian (c. 93–92 Ma), England (Bedfordshire, Kent, Cambridge area) and France (Yonne, Haute-Marne); common in the lower Albian Leymeriella tardefurcata Zone , ranging throughout overlying Albian zones and extending into the Chalk Marl and higher (Cenomanian, Schloenbachia varians and Holaster [= Crassiholaster] subglobosus zones) ( Collins, 1980; Carriol & Collins, 2000; Owen, 2002; Smith & Wright, 2003).