New and poorly known Valanginian ammonites from South-West ...

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102 Evgenij J. BARABOSHKIN & Irina A. MIKHAILOVARemarks: Busnardoites kojasdlilgcnsis clearly differsfrom die type of Busnardoites by the character of cyclicityof internal whorls (it has two bunches and a singlerib) and the sculpture of external whorls, as well as bystrongly involute discoidal shell.Hoplites proneeostatus (FFLIX, 1891), figured by KARAKASCH [SPU 103/495; 1907, p. 87, pi. 11, fig- la-b(only)]is very close to our species, but has more dense ribbingin the internal whorls. The specimen SPU 103/494 figuredon pi. 10, fig. lOa-b in KARAKASCH (1907) differsfrom Busnardoites in having umbilical and lateral tuberclesin the inner whorls. Probably it belongs to Bodrakieeras.Regrettably, only the umbilical parts of the internalwhorls of our new species were available for study. Bymorphology they are very close to the type of Busnardoites,but are distinguished by less coarse ribbing andless projecting tubercles. Therefore, we consider that thespecies can be refeircd to Busnardoites.campyDistribution: Lower Valanginian, Campylotoxialotoxa Zone of South-West Crimea.Genus Campylotoxiagen. nov.Generic name: derived from the type species.Type: Hoplites campylotoxus UHLIG (1902, p. 49, pi. 4,fig. 2), Lower Valanginian of Dolni Lisma, Carpathians.Slovakia.Diagnosis: Moderately evolute. medium size shells, havinghigh trapezoidal and sparingly high rounded-trapezoidalwhorl-section and slightly keeled venter. Umbilicusbroad, shallow; umbilical wall is steep to vertical,narrow.Ribs are grouped in cycles, which are separated bya weak constrictions in the earliest whorls (D20mm this border is marked by a spiny umbilicaltubercle. The cycle terminates by a 3-4 - branchedrib or a tripartite bidichotomic rib, one of the branchesof which has additional bifurcation in the mid - toupper third of the whorl height. The ventral flattenedtubercles are orthogonal to the plane of symmetry ofthe shell in the early whorls, but they become subparallelto it in adult. There are about 10 cycles of ribbing perwhorl.Suture line: is characterised by trifid umbilical lobe (U).deeper than the ventral lobe and noticeably inclined to thewedge of the seam; the first umbilical lobe (U 1 ) trifid.half as deep as the umbilical lobe.External saddle (V/U) is broad and asymmetric; thefirst lateral saddle (U/U 1 ) is also asymmetrical. It is higher,but narrower than the external saddle.Composition: Campylotoxia brasseuri (COLLIGNION,1962); C. evoluta sp. nov.; C campylotoxa (UHLIG,1902) with two subspecies: C. campylotoxa campylotoxa(UHLIG. 1902) and C. campylotoxa densocostatasubsp. nov.VIuIT:tnmFig. 8 — The suture line of Campylotoxia campylotoxa campylotoxa (UHLIG, 1902); MSU 95/15 at H=10 mm; Lower Valanginian,Campylotoxia campylotoxa Zone of Verkhorechie Village, base of Rezanaya Mt., bed Kp23/15,
New and poorly known Valanginian ammonites from South-West Crimea 103Table 1 — Schema of the biostratigraphic zonation of the Valanginian of the south east Crimea.UBSTAGER.Btisnardo,J.-P.Thieuloy,1979HYPOSTRATOTYPEZONESUBSTAGEN. I. Karakasch,1907BIASALASUBSTAGEV.V.Drushits, I960;B.T.Yanin,L.E.Vishnevsky,1989KACHA RIVERZONESUBSTAGEE. J. Barabosh km,1997bBODRAK RIVER -KACHA RIVERZONEUPPERLANGINI;LOWER.LANGINIANTeschenitescallidiscusHimantocerastri nodosumSaynocerasverrucosumThurmannicerascampyloloxumThurmanniceraspertransiensHAUTERIVIANGINIANF-lSandstoneswithDuvalia crimicaandtloiectypusConglomerateswithHoplitesandOsirea reciangularisUPPERHAUTERIVIANOWERfERIVlANJb$CrioceratitesduvallLeopoldialeopoldinaandTrlgoniacarhiataUPPERLANGINLElenicerastauricumTeschenitescallidiscus Himantocerastri nodosumZ
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