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Wanaea tendaguruensis
From Fensome et al., 2019:
Wanaea tendaguruensis Msaky 2007,50–51,53, fig.6, nos.1a–b,2–6,8.
Holotype: Msaky 2007, fig.6, no.3.
Age: Kimmeridgian.
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Original description: [Msaky, 2007, p. 50-51, 53]:
Wanaea tendaguruensis sp. nov. Figures 6.1a, b, 6.2–6.8
Diagnosis.—Cyst proximochorate, acavate, subcircular in polar view; hypocyst broadly biconical, antapex broadly rounded, lacking antapical horn. Archeopyle epicystal, operculum normally attached ventrally, principal archeopyle suture smooth, located immediately anterior of the paracingulum. Parasutural features indicated by paracingulum, but a few slender spines apparently aligned along parasutures near anta-pex. Epicyst small, flattened, with no paratabulation. Autophragm laevigate, occasionally with rare, slender spines near antapex. Two-layered paracingular flange, lacking distal trabeculum, located along posterior margin of paracingulum; equatorially positioned. Inner vacuolate layer (3 μm wide) surmounted by robust, radially arranged spines (5–7 μm long, 1–2 μm wide), locally interconnected at base by small processes.
Dimensions (20 specimens).—Length of hypocyst 32 (40) 50 μm; width of cyst (excluding paracingular flange) 44 (52) 57 μm; width of paracingular flange 7 (9) 12 μm; length of processes in paracingular flange 5 (6) 10 μm.
Holotype.—Slide 3b, England Finder reference X27/0; Figure 6.3. Antapical view.
Paratypes.—Slide 2b, England Finder reference R29/2, Figures 6.1a, b. Oblique right lateral view. Slide 3b, England Finder reference D14/0, Figures 6.2. Ventral view. Slide 2b, England Finder reference M5/4, Figure 6.4. Apical view. Slide 3b, England Finder reference N7/4, Figure 6.5. Antapical view. Slide 2b, England Finder reference V23/2, Figure 6.6. Antapical view. Slide 1b, England Finder reference Y18/0, Figure 6.7. Right lateral view. Slide 3b, England Finder reference H4/0, Figure 6.8. Oblique view.
Type locality.—Southern coastal Tanzania, Mandawa Basin; Tendaguru Formation, Trigonia smeei Bed, outcrop sample 9m; Upper Jurassic (Kimmeridgian).
Etymology.—From the type stratum.
Remarks.—Wanaea tendaguruensis sp. nov. lacks an antapical horn and has slender spines near the antapex which appear to be present along the parasutures; this could indicate partial paratabulation on the hypo-cyst. Although fully paratabulated hypocysts of species of Wanaea are unknown (Riding and Helby, 2001, p. 37), some species exhibit partial paratabulation on the hypocyst, e.g., W. acollaris. Apart from its lack of antapical horn and possible indication of parasutures near the antapex, the species is clearly attributable to Wanaea in having an epicystal archeopyle, flat epicyst, prominent paracingular flange, and broadly biconical hypocyst (see also Riding and Helby, 2001, p. 35). Wanaea tendaguruensis differs from species of Ctenidodinium Deflandre, 1939 emend. Woollam, 1983 (p. 190) which also have an epicystal archeopyle by lacking strong parasutural features on both the epicyst and the hypocyst; furthermore, biconical forms of Ctenidodinium are not known (Stover and Evitt, 1978, p. 223).
Comparison.—Wanaea tendaguruensis is similar to other members of the genus with prominent paracingular flanges. It is comparable to W. digitata in having a two-layered paracingular flange lacking a distal trabeculum, but the outer layer of the paracingular flange of W. tendaguruensis has fewer, more robust spines than those of W. digitata. Wanaea digitata has a distinct antapical horn, thus further differentiating it from W. tendaguruensis which has a broadly rounded antapex. Moreover, W. tendaguruensis bears slender parasutural spines near the antapex; this also clearly segregates it from W. digitata.
Occurrence.—Rare in outcrop samples 9f, 9f1, 9m, and 9p; Trigonia smeei Bed of the Tendaguru Formation.
Wanaea tendaguruensis Msaky 2007,50–51,53, fig.6, nos.1a–b,2–6,8.
Holotype: Msaky 2007, fig.6, no.3.
Age: Kimmeridgian.
---------------------------------------------------------------------------------------------------
Original description: [Msaky, 2007, p. 50-51, 53]:
Wanaea tendaguruensis sp. nov. Figures 6.1a, b, 6.2–6.8
Diagnosis.—Cyst proximochorate, acavate, subcircular in polar view; hypocyst broadly biconical, antapex broadly rounded, lacking antapical horn. Archeopyle epicystal, operculum normally attached ventrally, principal archeopyle suture smooth, located immediately anterior of the paracingulum. Parasutural features indicated by paracingulum, but a few slender spines apparently aligned along parasutures near anta-pex. Epicyst small, flattened, with no paratabulation. Autophragm laevigate, occasionally with rare, slender spines near antapex. Two-layered paracingular flange, lacking distal trabeculum, located along posterior margin of paracingulum; equatorially positioned. Inner vacuolate layer (3 μm wide) surmounted by robust, radially arranged spines (5–7 μm long, 1–2 μm wide), locally interconnected at base by small processes.
Dimensions (20 specimens).—Length of hypocyst 32 (40) 50 μm; width of cyst (excluding paracingular flange) 44 (52) 57 μm; width of paracingular flange 7 (9) 12 μm; length of processes in paracingular flange 5 (6) 10 μm.
Holotype.—Slide 3b, England Finder reference X27/0; Figure 6.3. Antapical view.
Paratypes.—Slide 2b, England Finder reference R29/2, Figures 6.1a, b. Oblique right lateral view. Slide 3b, England Finder reference D14/0, Figures 6.2. Ventral view. Slide 2b, England Finder reference M5/4, Figure 6.4. Apical view. Slide 3b, England Finder reference N7/4, Figure 6.5. Antapical view. Slide 2b, England Finder reference V23/2, Figure 6.6. Antapical view. Slide 1b, England Finder reference Y18/0, Figure 6.7. Right lateral view. Slide 3b, England Finder reference H4/0, Figure 6.8. Oblique view.
Type locality.—Southern coastal Tanzania, Mandawa Basin; Tendaguru Formation, Trigonia smeei Bed, outcrop sample 9m; Upper Jurassic (Kimmeridgian).
Etymology.—From the type stratum.
Remarks.—Wanaea tendaguruensis sp. nov. lacks an antapical horn and has slender spines near the antapex which appear to be present along the parasutures; this could indicate partial paratabulation on the hypo-cyst. Although fully paratabulated hypocysts of species of Wanaea are unknown (Riding and Helby, 2001, p. 37), some species exhibit partial paratabulation on the hypocyst, e.g., W. acollaris. Apart from its lack of antapical horn and possible indication of parasutures near the antapex, the species is clearly attributable to Wanaea in having an epicystal archeopyle, flat epicyst, prominent paracingular flange, and broadly biconical hypocyst (see also Riding and Helby, 2001, p. 35). Wanaea tendaguruensis differs from species of Ctenidodinium Deflandre, 1939 emend. Woollam, 1983 (p. 190) which also have an epicystal archeopyle by lacking strong parasutural features on both the epicyst and the hypocyst; furthermore, biconical forms of Ctenidodinium are not known (Stover and Evitt, 1978, p. 223).
Comparison.—Wanaea tendaguruensis is similar to other members of the genus with prominent paracingular flanges. It is comparable to W. digitata in having a two-layered paracingular flange lacking a distal trabeculum, but the outer layer of the paracingular flange of W. tendaguruensis has fewer, more robust spines than those of W. digitata. Wanaea digitata has a distinct antapical horn, thus further differentiating it from W. tendaguruensis which has a broadly rounded antapex. Moreover, W. tendaguruensis bears slender parasutural spines near the antapex; this also clearly segregates it from W. digitata.
Occurrence.—Rare in outcrop samples 9f, 9f1, 9m, and 9p; Trigonia smeei Bed of the Tendaguru Formation.