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Dinogymnium aerlicum ssp. curvispinum
Plate 4, Figures 1-5
Holotype: Plate 4, Figures 1, 2
Type Locality: Vergol outcrop, late Valanginian, Bed V124M, peregrinus ammonite Zone, peregrinus Sub-zone. Holotype: Slide V124M(1), E.F. W35.3.
Derivation of Name: From the Latin curvus, bent and spina, thorn - in reference to the curved terminal spine.
Diagnosis: A small, completely smooth, spindle-shaped subspecies of Dinogymnium aerlicum with a sharply pointed antapex bearing a short, curved terminal spine. There is no clear cingulum although this is indicated by two surface folds at approximately the mid-point of the cyst. A small apical "lid" is sometimes observed, hinged close to the apex.
Dimensions: Holotype 51 × 35 μm.
Overall 51 (50) 48 μm × 35 (34) 30 μm.
Specimens measured - 4.
Remarks: Dinogymnium aerlicum subsp. curvispinum was recorded in Bed V91M (early Valanginian, inostranzewi Zone, inostranzewi Sub-zone) and in Beds V123M and V124M from the late Valanginian. The last two occurrences span the boundary between the verrucosum and peregrinus Zones. A single specimen was also recorded in La Charce sample LCH113M, top verrucosum Zone. All of these occurrences are significantly younger than the late Berriasian age quoted by Londeix et al. (op. cit.) for D. aerlicum subsp. aerlicum.
Holotype: Plate 4, Figures 1, 2
Type Locality: Vergol outcrop, late Valanginian, Bed V124M, peregrinus ammonite Zone, peregrinus Sub-zone. Holotype: Slide V124M(1), E.F. W35.3.
Derivation of Name: From the Latin curvus, bent and spina, thorn - in reference to the curved terminal spine.
Diagnosis: A small, completely smooth, spindle-shaped subspecies of Dinogymnium aerlicum with a sharply pointed antapex bearing a short, curved terminal spine. There is no clear cingulum although this is indicated by two surface folds at approximately the mid-point of the cyst. A small apical "lid" is sometimes observed, hinged close to the apex.
Dimensions: Holotype 51 × 35 μm.
Overall 51 (50) 48 μm × 35 (34) 30 μm.
Specimens measured - 4.
Remarks: Dinogymnium aerlicum subsp. curvispinum was recorded in Bed V91M (early Valanginian, inostranzewi Zone, inostranzewi Sub-zone) and in Beds V123M and V124M from the late Valanginian. The last two occurrences span the boundary between the verrucosum and peregrinus Zones. A single specimen was also recorded in La Charce sample LCH113M, top verrucosum Zone. All of these occurrences are significantly younger than the late Berriasian age quoted by Londeix et al. (op. cit.) for D. aerlicum subsp. aerlicum.