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Chlamydophorella caminus
Original description Duxbury, 2024:
Plate 5, Figures 13, 17
Gardodinium trabeculosum (Gocht 1959) Alberti 1961. – LEEREVELD 1997a, figs. 8e, 9a.
Holotype: Plate 5, Figure 13
Type Locality: Vergol outcrop, Valanginian. Holotype: late Valanginian, Bed V132M, peregrinus ammonite Zone, peregrinus
Sub-zone, Slide V132M/1, E.F. S48.4.
Derivation of Name: From the Latin caminus, chimney - in reference to the apical projection.
Diagnosis: A thin-walled, holocavate species of moderate size with an ovoidal, tapering autocyst terminating in a short, distally closed and rounded projection. The hypocyst is semicircular in outline. Short, stout processes link the autophragm and a significantly thinner, very finely reticulo-fenestrate ectophragm. A broad-based, hollow apical horn extends the ectophragm and this is open distally. There is no clear indication of tabulation or dorso- ventral flattening. The archeopyle is apical, with the operculum attached.
Dimensions: Holotype: 63×46 μm.
Overall - 63 (59) 56 μm×48 (45) 43 μm.
Specimens measured – 5.
Remarks: Chlamydophorella caminus is similar to Chlamydophorella pyriformis (Vozzhennikova 1967) Davey 1978 in having a characteristically ovoidal shape and prominent ectophragmal apical horn. It differs, however in being significantly smaller, in lacking any indication of tabulation, in bearing less numerous and stouter autophragmal processes and in having a very finely reticulo- fenestrate ectophragm as opposed to the smooth ectophragm of C. pyriformis, as described by Lentin and Vozzhennikova (1990, p. 102). Harding (1996, p. 359) considered Chlamydophorella pyriformis to be a questionable taxonomic junior synonym of Chlamydophorella trabeculosa (Gocht 1959) Davey 1978 (as Gardodinium trabeculosum), although he stated, "The possible synonymy of G. trabeculosum and G. pyriforme requires further investigation".
Describing his type material for C. trabeculosa, Gocht (1959, p. 62) stated (translation), "All are dorso-ventrally flattened", and this seems to be a significant feature of both Gocht's material and that of Alberti 1961 (as Gardodinium eisenackii), although Harding (op. cit., p. 361) recognised only, "Moderate primary dorso-ventral compression". Further features observed in Gocht and Alberti's material which seem typical of Chlamydophorella trabeculosa include "shoulders", which give some angularity to the epicyst, and clear lateral cingular notches. All of these features, apparently typical of C. trabeculosa, are absent from C. pyriformis and on that basis the present author agrees with Lentin (see Harding 1996, p. 364) in her reluctance to believe that these species are conspecific.
The specimens illustrated by Leereveld (1997a, figs. 8e, 9a) as Gardodinium trabeculosum are here included in Chlamydophorella caminus. Undoubtedly, other authors have also assigned various taxa to C. trabeculosa which lack the typical features noted above, but largely without illustration, precluding their re-interpretation. Chlamydophorella trabeculosa ranges no older than Bed C7H at Speeton (early Hauterivian, base inversum Zone - Duxbury 2023, fig. 4), and it was absent from the current study. Chlamydophorella caminus is a long-ranging species, recorded from Vergol Bed B142M (early Valanginian, pertransiens Zone, pertransiens Sub-zone) to the highest sample analysed from La Charce (early Hauterivian, loryi Zone). However, its FO is an important marker in being very closely above the Berriasian/Valanginian boundary. At Vergol, there were no Chlamydophorella spp. bearing a prominent apical horn pre-Valanginian.
A similar near-base pertransiens FO was illustrated for Chlamydophorella caminus by Leereveld (1997a, fig. 2, as Gardodinium trabeculosum), although that author did not analyse the otopeta Zone. Similarly, Monteil (1992b, Table 1) recorded "Gardodinium trabeculosum" (without illustration), but only as deep as the uppermost pertransiens Zone. This might again be Chlamydophorella caminus.
Plate 5, Figures 13, 17
Gardodinium trabeculosum (Gocht 1959) Alberti 1961. – LEEREVELD 1997a, figs. 8e, 9a.
Holotype: Plate 5, Figure 13
Type Locality: Vergol outcrop, Valanginian. Holotype: late Valanginian, Bed V132M, peregrinus ammonite Zone, peregrinus
Sub-zone, Slide V132M/1, E.F. S48.4.
Derivation of Name: From the Latin caminus, chimney - in reference to the apical projection.
Diagnosis: A thin-walled, holocavate species of moderate size with an ovoidal, tapering autocyst terminating in a short, distally closed and rounded projection. The hypocyst is semicircular in outline. Short, stout processes link the autophragm and a significantly thinner, very finely reticulo-fenestrate ectophragm. A broad-based, hollow apical horn extends the ectophragm and this is open distally. There is no clear indication of tabulation or dorso- ventral flattening. The archeopyle is apical, with the operculum attached.
Dimensions: Holotype: 63×46 μm.
Overall - 63 (59) 56 μm×48 (45) 43 μm.
Specimens measured – 5.
Remarks: Chlamydophorella caminus is similar to Chlamydophorella pyriformis (Vozzhennikova 1967) Davey 1978 in having a characteristically ovoidal shape and prominent ectophragmal apical horn. It differs, however in being significantly smaller, in lacking any indication of tabulation, in bearing less numerous and stouter autophragmal processes and in having a very finely reticulo- fenestrate ectophragm as opposed to the smooth ectophragm of C. pyriformis, as described by Lentin and Vozzhennikova (1990, p. 102). Harding (1996, p. 359) considered Chlamydophorella pyriformis to be a questionable taxonomic junior synonym of Chlamydophorella trabeculosa (Gocht 1959) Davey 1978 (as Gardodinium trabeculosum), although he stated, "The possible synonymy of G. trabeculosum and G. pyriforme requires further investigation".
Describing his type material for C. trabeculosa, Gocht (1959, p. 62) stated (translation), "All are dorso-ventrally flattened", and this seems to be a significant feature of both Gocht's material and that of Alberti 1961 (as Gardodinium eisenackii), although Harding (op. cit., p. 361) recognised only, "Moderate primary dorso-ventral compression". Further features observed in Gocht and Alberti's material which seem typical of Chlamydophorella trabeculosa include "shoulders", which give some angularity to the epicyst, and clear lateral cingular notches. All of these features, apparently typical of C. trabeculosa, are absent from C. pyriformis and on that basis the present author agrees with Lentin (see Harding 1996, p. 364) in her reluctance to believe that these species are conspecific.
The specimens illustrated by Leereveld (1997a, figs. 8e, 9a) as Gardodinium trabeculosum are here included in Chlamydophorella caminus. Undoubtedly, other authors have also assigned various taxa to C. trabeculosa which lack the typical features noted above, but largely without illustration, precluding their re-interpretation. Chlamydophorella trabeculosa ranges no older than Bed C7H at Speeton (early Hauterivian, base inversum Zone - Duxbury 2023, fig. 4), and it was absent from the current study. Chlamydophorella caminus is a long-ranging species, recorded from Vergol Bed B142M (early Valanginian, pertransiens Zone, pertransiens Sub-zone) to the highest sample analysed from La Charce (early Hauterivian, loryi Zone). However, its FO is an important marker in being very closely above the Berriasian/Valanginian boundary. At Vergol, there were no Chlamydophorella spp. bearing a prominent apical horn pre-Valanginian.
A similar near-base pertransiens FO was illustrated for Chlamydophorella caminus by Leereveld (1997a, fig. 2, as Gardodinium trabeculosum), although that author did not analyse the otopeta Zone. Similarly, Monteil (1992b, Table 1) recorded "Gardodinium trabeculosum" (without illustration), but only as deep as the uppermost pertransiens Zone. This might again be Chlamydophorella caminus.