Mollusks from late Mesozoic seep deposits, chiefly in California Kaim, Andrzej Jenkins, Robert G. Tanabe, Kazushige Kiel, Steffen Zootaxa 2014 3861 5 401 440 [151,478,332,358] Gastropoda Melanodrymiidae Abyssomelania Animalia 15 416 Mollusca species campbellae sp. nov.    Typelocality and strata: Cold Fork of Cottonwood Creek, Tehama County, California, USA; locality # 1 in Kiel et al.(2008b); Lodoga Formation, Great Valley Group; Albian (Early Cretaceous.)   Holotype: GZG.INV.84982, two and half well-preserved adolescent whorls 33.1 mmhigh and 19.3 mmwide.   Paratypes: GZG.INV.84983, two adult whorls 39 mmhigh and 30.2 mmwide, we estimate that the complete specimen could be 80 mmhigh, GZG.INV.84984 fragmentary specimen displaying the ornamentation on the shell base.  Additional material. Five fragmentary specimens from the typelocality including juvenile (GZG.INV.84985) illustrated in Fig. 6N.   Diagnosis.Large tall gastropods (reaching 80 mmin length) with smooth lateral flanks of adolescent/adult shell and spirally ornamented base. Growth lines opisthocline throughout the entire lateral flank. Shell largest diameter slightly above abapical suture.   Description.Tall shell with largest diameter of whorl slightly above the abapical suture. Shell surface smooth with opisthocline growth lines only and abyssomelanid riblets at least at last two whorls. Shell base ornamented by five broad spiral ribs intersected by growth lines with no knobs. Suture weakly incised. Protoconch, juvenile teleoconch and aperture not preserved.   Remarks.  A. campbellaediffers from  A. cramptoniby its much larger size, and its stronger and less numerous spiral ribs on the base. The largest diameter of the whorl is only slightly above the abapical suture giving less bulgy appearance than in  A. cramptoni. The angulation of the growth lines is in the middle of lateral flank in  A. campbellaewhile in the upper part in  A. cramptoni.   Etymology.For Kathleen A. Campbell, for her pioneering work on the fossil seep faunas of California.