Back
Evansia spongogranulata
From Fensome et al., 2019:
Evansia spongogranulata Below, 1990, p.78–79, pl.19, figs.6–13; pl.20, figs.2,4–5,7–8; text-figs.23a–d. Holotype: Below, 1990, pl.19, figs.6–9,12. Contrary to the opinion of Lentin and Williams (1993, p.215), this name is validly published. Below (1987a, p.6) stated that, unless otherwise indicated, all the material is in his personal collection. Since Below (1987a, 1987b, 1990) are parts I to III of a single study, we agree with J. Jansonius (personal communication) that Below's (1987a) repository statement refers to all three publications, fulfilling the requirement of ICN Article 40.7. Age: Aalenian–Bajocian.
---------------------------------------------------------------------------------------------------
Original description Below, 1990:
Deriviation of the name: based on the granular, spongy-structured Luxuria. Holotype: specimen S3一1622(Kl)2/ll (Plate 19, Figs. 6-9, 12).
Typical location: Eschacher landslide of Scheffheu.
Typical stratum: Aalenian, concave zone.
Description:
Vesicle/plate arrangement of the dinoflagellate Amphiesma cop, pop, cap, 3', 3a, 6'', 7c, 6''', 2'''', as, FM, ls, rs,
ps; 1' insert; tegulation 4*, 3**, 4***, 2****, 7c, 4•, 4•• 3•••; growth of thecal plates in a gonyaulocoid manner;
Zygote cyst habitus proximate, acavate to cornucavate, somewhat ellipsoidal to ovaloid, epicyst rounded tentoriate with a short apical horn and slightly smaller than the rounded coniform hypocyst, somewhat flattened dorso-ventrally; Wall of thin pedium and spongy luxuria with partly densely attached granules, surface of the adcingular and cingular areas often covered with trichocyst pores of the thcka reflecting pustules, finis as low ridges, which are often reduced to short sections of granules or completely; Areas of interest: XPR/cop, pop, cap, 3', 3a, 6", 7c, 6'", 2"", Xs/as, FM, ps; PR undifferentiated or cop tiny, forming the tip of the apical protuberance and surrounded by pop, area cap small; 3 apicals: IV-nE 1'(V), VI-nE2'(L), Vl-nE3' (R); 3 anterior intercalaries: caroidale 1a (LDL), fastigiate 2a (D), caroidale 3a (DR); 6 precingulate: anterior geniculate v-nEl" (VVL), anterior geniculate V-nE2" (LVL), anterior geniculate V-nE3" (DL), anterior geniculate V-nE4" (DR), anterior geniculate V-nES" (RVR), anterior geniculate V-nE6" (VVR); Cingulum left-handed spiral, dented, heptapartite from lati le to 6c and iso-fastigiater 7c; 6 Postcingulates:
posterior linear V-nE 1'''(VVL), posterior linear IV-nE 2"'(VL), posterior geniculate V-nE 3"'(LDL), posterior linear IV-nE 4"'(D), posterior linear IV-nE 5"'(RDR), posterior linear V-nE 6"'(VR); 2 antapics: V 1''' descending toward VL, VI2"' poleward, slightly inclined toward R; sulcus slightly depressed, partite; archaeopyle anteriorly intercalary, 1a + 2a + 3a; operculum solvate, opercular plates secat, general opercular formula 1a5 + 2a5 + 3a5.
Holotype matrix:
Length: 41 µm, width: 30 µm, thickness: 27 µm.
Note:
The arrangement, with its variable number of anterior intercalaries, corresponds to the arrangement of Evansia eschachensis. The fins are generally poorly developed, but in this species, ventral areas, e.g., 1' and 2', are often finite. The three apical areas show the arrangement typical of the genus Evansia, with a ventral 1' insert, a 2' located sinistral to the PR, and a 3' located dextral to the PR. They are thus clearly different from the pattern in Carpathodinium or Paragonyaulacysta. Only specimen S1-1617 (K1)2/15 deviates from this. In addition to a vaguely defined small l', it clearly shows the large 3' between 5", 6", 1" and the intercalary area group dextral to the apex, as well as the somewhat smaller 2' sinistral to the apex, i.e., the arrangement typical for Carparhodinium, Paraevansia n.gen., and Paragonyaulacysta (see Fig. 23c, d). The homologation of the area l', which differs greatly in its position relative to the apex, in these genera is confirmed by the porichnion at the 1' margin. This is found, for example, in Evansia eschachensis at the anterior dextral margin from 1' to 3', in specimen Sl-1617(K1)2/15 of Evansia spongogranulata, as well as in Carpathodinium and Paragonyaulacysta taxa at the finis 1'/6" within l'. It is assumed that the Paragonyaulacysta arrangement of apical areas arose from the enlargement of 3' at the expense of 1' and the corresponding displacement of the suture/finis 3'/1' from the Evansia tabulation.
Some specimens reflect trichocyst pores in the form of low granule rings and pustules, thus allowing the reconstruction of the genus' tegulation scheme. In the adcingular, cingular, apical, and antapical area series, they occur in groups surrounded by limbi without reflected trichocyst spores. The detailed scheme is: R2*, R1, F*, L1*
3**,
4***,
F****, R?L1****
R4c, R3c, R2c, R1c, Fc, L1c, L2c,
R2+, R1+, F+, L1+,
R1++, F++, L1++, L2++,
R1+++, F+++, L1+++
The cingulum was overlapped only by the postcingular plates, while the anterior abutted the precingulatar plates without overlap. The growth pattern of thecal plates is, according to the distribution of the limbi to close central areas with reflected trichocyst pores, gonyaulacoid.
Evansia spongogranulata Below, 1990, p.78–79, pl.19, figs.6–13; pl.20, figs.2,4–5,7–8; text-figs.23a–d. Holotype: Below, 1990, pl.19, figs.6–9,12. Contrary to the opinion of Lentin and Williams (1993, p.215), this name is validly published. Below (1987a, p.6) stated that, unless otherwise indicated, all the material is in his personal collection. Since Below (1987a, 1987b, 1990) are parts I to III of a single study, we agree with J. Jansonius (personal communication) that Below's (1987a) repository statement refers to all three publications, fulfilling the requirement of ICN Article 40.7. Age: Aalenian–Bajocian.
---------------------------------------------------------------------------------------------------
Original description Below, 1990:
Deriviation of the name: based on the granular, spongy-structured Luxuria. Holotype: specimen S3一1622(Kl)2/ll (Plate 19, Figs. 6-9, 12).
Typical location: Eschacher landslide of Scheffheu.
Typical stratum: Aalenian, concave zone.
Description:
Vesicle/plate arrangement of the dinoflagellate Amphiesma cop, pop, cap, 3', 3a, 6'', 7c, 6''', 2'''', as, FM, ls, rs,
ps; 1' insert; tegulation 4*, 3**, 4***, 2****, 7c, 4•, 4•• 3•••; growth of thecal plates in a gonyaulocoid manner;
Zygote cyst habitus proximate, acavate to cornucavate, somewhat ellipsoidal to ovaloid, epicyst rounded tentoriate with a short apical horn and slightly smaller than the rounded coniform hypocyst, somewhat flattened dorso-ventrally; Wall of thin pedium and spongy luxuria with partly densely attached granules, surface of the adcingular and cingular areas often covered with trichocyst pores of the thcka reflecting pustules, finis as low ridges, which are often reduced to short sections of granules or completely; Areas of interest: XPR/cop, pop, cap, 3', 3a, 6", 7c, 6'", 2"", Xs/as, FM, ps; PR undifferentiated or cop tiny, forming the tip of the apical protuberance and surrounded by pop, area cap small; 3 apicals: IV-nE 1'(V), VI-nE2'(L), Vl-nE3' (R); 3 anterior intercalaries: caroidale 1a (LDL), fastigiate 2a (D), caroidale 3a (DR); 6 precingulate: anterior geniculate v-nEl" (VVL), anterior geniculate V-nE2" (LVL), anterior geniculate V-nE3" (DL), anterior geniculate V-nE4" (DR), anterior geniculate V-nES" (RVR), anterior geniculate V-nE6" (VVR); Cingulum left-handed spiral, dented, heptapartite from lati le to 6c and iso-fastigiater 7c; 6 Postcingulates:
posterior linear V-nE 1'''(VVL), posterior linear IV-nE 2"'(VL), posterior geniculate V-nE 3"'(LDL), posterior linear IV-nE 4"'(D), posterior linear IV-nE 5"'(RDR), posterior linear V-nE 6"'(VR); 2 antapics: V 1''' descending toward VL, VI2"' poleward, slightly inclined toward R; sulcus slightly depressed, partite; archaeopyle anteriorly intercalary, 1a + 2a + 3a; operculum solvate, opercular plates secat, general opercular formula 1a5 + 2a5 + 3a5.
Holotype matrix:
Length: 41 µm, width: 30 µm, thickness: 27 µm.
Note:
The arrangement, with its variable number of anterior intercalaries, corresponds to the arrangement of Evansia eschachensis. The fins are generally poorly developed, but in this species, ventral areas, e.g., 1' and 2', are often finite. The three apical areas show the arrangement typical of the genus Evansia, with a ventral 1' insert, a 2' located sinistral to the PR, and a 3' located dextral to the PR. They are thus clearly different from the pattern in Carpathodinium or Paragonyaulacysta. Only specimen S1-1617 (K1)2/15 deviates from this. In addition to a vaguely defined small l', it clearly shows the large 3' between 5", 6", 1" and the intercalary area group dextral to the apex, as well as the somewhat smaller 2' sinistral to the apex, i.e., the arrangement typical for Carparhodinium, Paraevansia n.gen., and Paragonyaulacysta (see Fig. 23c, d). The homologation of the area l', which differs greatly in its position relative to the apex, in these genera is confirmed by the porichnion at the 1' margin. This is found, for example, in Evansia eschachensis at the anterior dextral margin from 1' to 3', in specimen Sl-1617(K1)2/15 of Evansia spongogranulata, as well as in Carpathodinium and Paragonyaulacysta taxa at the finis 1'/6" within l'. It is assumed that the Paragonyaulacysta arrangement of apical areas arose from the enlargement of 3' at the expense of 1' and the corresponding displacement of the suture/finis 3'/1' from the Evansia tabulation.
Some specimens reflect trichocyst pores in the form of low granule rings and pustules, thus allowing the reconstruction of the genus' tegulation scheme. In the adcingular, cingular, apical, and antapical area series, they occur in groups surrounded by limbi without reflected trichocyst spores. The detailed scheme is: R2*, R1, F*, L1*
3**,
4***,
F****, R?L1****
R4c, R3c, R2c, R1c, Fc, L1c, L2c,
R2+, R1+, F+, L1+,
R1++, F++, L1++, L2++,
R1+++, F+++, L1+++
The cingulum was overlapped only by the postcingular plates, while the anterior abutted the precingulatar plates without overlap. The growth pattern of thecal plates is, according to the distribution of the limbi to close central areas with reflected trichocyst pores, gonyaulacoid.