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Phelodinium kozlowskii
Phelodinium kozlowskii (Gorka, 1963) Lindgren, 1984
Originally Lejeunia (an illegitimate generic name), subsequently Astrocysta, thirdly Senegalinium, fourthly (and now) Phelodinium.
Tax. jr. synonym of Phelodinium (as Lejeunia) tricuspe (O. Wetzel, 1933) Stover and Evitt, 1978, according to Harker and Sarjeant, 1975; however, Lindgren, 1984 retained Phelodinium kozlowskii as a separate species.
Holotype: Gorka, 1963, pl.5, fig.4
Age: Late Maastrichtian
Description: Lindgren 1984, p. 181-183:
Cornucavate microfossil. Pericyst ambitus pentagonal. Epipericyst broadbased triangular with straight to slightly convex sides. Apex prolonged into a short narrow horn with a rounded tip. Hypopericyst with slightly concave sides, and a broad concave base. Antapex with two equal symmetrically located long, narrow antapical horns, with an acute tip. Endocyst apressed to pericyst except at the tips of horns. Periphragm with nontabular ornament, striate. Endophragm smooth. Paratabulation indicated by cingulum and sulcus. Cingulum region with a clearly delimited ridge with finely denticulate margins. Sulcus indicated by the antapical extending of cingulum. Archeopyle indiscernible.
Material. 6 specimens measured.
Dimensions:
Length and width of pericyst:
Length (µm) Range: 76-112
Width (µm) Range: 66-82
Remarks: Lindgren 1984, p. 181-183:
The present specimens are cornucavate (fig. 14K, L). They were identified by Dr. Hanna Górka (personal communication, Stockholm (1979) as conspecific with Lejeunia kozlowlkii GORKA. The type specimen of L. kozlowskii is not available for examination.
Harland (1973: 673) considered Lejeunia kozlowskii as a junior synonym of Lejeunia tricuspis and pointed out that differences among the specimens illustrated by Górka (l963: pl. 5, figs. 1 4) "can be accomodated by specific variation". This opinion on the synonymy was confirmed by Harker & Sarjeant (1975: 223) after the transference of both species to Astrocysta (Davey 1970: 360). Lejeunia kozlowlkii was not recorded as a separate taxon at the transference of species of Lejeunia to Lejeunecysta (Artzner & Dörhöfer 1978: 1381), neither in the review by Stover & Evitt (1978).
Through the reexamination of the type material of Lejeunecyssa tricuspis (Wetzel 1933: 166) Artzner & Dörhöfer 1978: 1381 it was demonstrated that only one wall layer can be discerned; the cavate appearance on published illustrations results from surficial ridges and folds (LeJeune Carpentier & Sarjeant 1981: 21). Despite specimens of Lejeunia tricuspis were recorded only once in a number of only about five (Wetzel 1933: 166) this taxon subsequently has been transferred to four genera. It was introduced as Peridium tricuspis with an insufficient diagnosis recording only pointed horns, prominent cingulum region, and concave sides. The main characters in the actual classification, endo and pericyst and pericoels, were omitted. It was referred to Phelodinium by Stover & Evitt (1978: 118).
Lejeunia kozlowskii was not included in the synonymy of Lejeunecysta tricuspis published at the reexamination of this species (Lejeune Carpentier & Sarjeant 1981: 21).
If the wall layers are considered to be of taxonomic importance at the rank of genus the species kozlowskii and tricuspis have to be referred to different genera. However, in populations of modern cavate dinoflagellate species the endocyst may be absent in varying proportions of the cysts. The presence of acavate forms in cavate natural species indicates that the taxonomic value of the endocyst must be judged by reference to numerous specimens (Wall & Dale 1968: 283).
Originally Lejeunia (an illegitimate generic name), subsequently Astrocysta, thirdly Senegalinium, fourthly (and now) Phelodinium.
Tax. jr. synonym of Phelodinium (as Lejeunia) tricuspe (O. Wetzel, 1933) Stover and Evitt, 1978, according to Harker and Sarjeant, 1975; however, Lindgren, 1984 retained Phelodinium kozlowskii as a separate species.
Holotype: Gorka, 1963, pl.5, fig.4
Age: Late Maastrichtian
Description: Lindgren 1984, p. 181-183:
Cornucavate microfossil. Pericyst ambitus pentagonal. Epipericyst broadbased triangular with straight to slightly convex sides. Apex prolonged into a short narrow horn with a rounded tip. Hypopericyst with slightly concave sides, and a broad concave base. Antapex with two equal symmetrically located long, narrow antapical horns, with an acute tip. Endocyst apressed to pericyst except at the tips of horns. Periphragm with nontabular ornament, striate. Endophragm smooth. Paratabulation indicated by cingulum and sulcus. Cingulum region with a clearly delimited ridge with finely denticulate margins. Sulcus indicated by the antapical extending of cingulum. Archeopyle indiscernible.
Material. 6 specimens measured.
Dimensions:
Length and width of pericyst:
Length (µm) Range: 76-112
Width (µm) Range: 66-82
Remarks: Lindgren 1984, p. 181-183:
The present specimens are cornucavate (fig. 14K, L). They were identified by Dr. Hanna Górka (personal communication, Stockholm (1979) as conspecific with Lejeunia kozlowlkii GORKA. The type specimen of L. kozlowskii is not available for examination.
Harland (1973: 673) considered Lejeunia kozlowskii as a junior synonym of Lejeunia tricuspis and pointed out that differences among the specimens illustrated by Górka (l963: pl. 5, figs. 1 4) "can be accomodated by specific variation". This opinion on the synonymy was confirmed by Harker & Sarjeant (1975: 223) after the transference of both species to Astrocysta (Davey 1970: 360). Lejeunia kozlowlkii was not recorded as a separate taxon at the transference of species of Lejeunia to Lejeunecysta (Artzner & Dörhöfer 1978: 1381), neither in the review by Stover & Evitt (1978).
Through the reexamination of the type material of Lejeunecyssa tricuspis (Wetzel 1933: 166) Artzner & Dörhöfer 1978: 1381 it was demonstrated that only one wall layer can be discerned; the cavate appearance on published illustrations results from surficial ridges and folds (LeJeune Carpentier & Sarjeant 1981: 21). Despite specimens of Lejeunia tricuspis were recorded only once in a number of only about five (Wetzel 1933: 166) this taxon subsequently has been transferred to four genera. It was introduced as Peridium tricuspis with an insufficient diagnosis recording only pointed horns, prominent cingulum region, and concave sides. The main characters in the actual classification, endo and pericyst and pericoels, were omitted. It was referred to Phelodinium by Stover & Evitt (1978: 118).
Lejeunia kozlowskii was not included in the synonymy of Lejeunecysta tricuspis published at the reexamination of this species (Lejeune Carpentier & Sarjeant 1981: 21).
If the wall layers are considered to be of taxonomic importance at the rank of genus the species kozlowskii and tricuspis have to be referred to different genera. However, in populations of modern cavate dinoflagellate species the endocyst may be absent in varying proportions of the cysts. The presence of acavate forms in cavate natural species indicates that the taxonomic value of the endocyst must be judged by reference to numerous specimens (Wall & Dale 1968: 283).