Foraminifera taxon details
Kristanita Falzoni, Rettori & Gale, 2025 †
1831678 (urn:lsid:marinespecies.org:taxname:1831678)
accepted
Genus
Tetrataxis humilis Kristan, 1957 † accepted as Duotaxis humilis (Kristan, 1957) † accepted as Kristanita humilis (Kristan, 1957) † (type by original designation)
marine
fossil only
feminine
Falzoni, F.; Rettori, R.; Gale, L.; Mikhalevich, V. I.; Weinmann, A. E.; Parente, M. (2025). Taxonomy and palaeoecology of the Mesozoic family Duotaxidae Mikhalevich (Foraminifera). <em>Papers in Palaeontology.</em> 11(5): 1-28., available online at https://doi.org/10.1002/spp2.70032
page(s): p. 15. [details] Available for editors
[request]
page(s): p. 15. [details] Available for editors
[request]
Original description Diagnosis. Trochospiral, conical test with weakly concave to weakly inflated umbilical side, 3–4 elongated chambers in...
Original description Diagnosis. Trochospiral, conical test with weakly concave to weakly inflated umbilical side, 3–4 elongated chambers in the last whorl, spiral sutures strongly to weakly keeled, umbilical cavity developed from early whorls to the umbilicus, which appears strongly depressed; aperture, a wide horizontal slit opening at the base of the apertural face of the last chamber in an irregularly developed tri- to tetralobate umbilical depression and with supplementary structures (‘längliche Zapfen’ in Kristan 1957) in umbilical to extra-umbilical position.
Description. Multi-chambered, trochospiral, conical test with rounded apical margin and low to moderately high, often asymmetric trochospire. The two specimens identified as Kristanita inflata (= Tetrataxis inflata) by Kristan-Tollmann (1964), in plate 7, figures 4 and 7 show that the early chambers of the first two whorls are small, globular and very slowly increasing in size (Fig. 5U, Y). Adult stage with chambers crescentic and elongated, in the third whorl rapidly increasing, in the final whorls more slowly increasing in size; the chamber height remains constant especially in the last two whorls; sutures strongly curved, oblique and keeled (Figs 4–6). On the umbilical side, 3–4 chambers in the last whorl that may be weakly concave to weakly inflated, initially subtrapezoidal–subtriangular in shape; last chamber often semicircular and occupying nearly half whorl; sutures depressed and often not visible (Figs 4–6). Umbilical cavity developed along the axis of the test from early whorls to the umbilicus (Fig. 8K), which is slightly depressed. The shape of the transverse section of the umbilical cavity changes through ontogeny depending on the number of chambers in the whorl. The section appears polygonal in early whorls (with 5–7 chambers per whorl) to square in later whorls (with 3–4 chambers per whorl) (Fig. 8Q–T). Aperture, a slit opening at the base of the apertural face in a tri- to tetralobate umbilical depression and partially covered by supplementary structures in umbilical to extra-umbilical position (Figs 4D, F, Q, S, 5F, Z). Wall simple, single-layered, finely agglutinated and dark in thin section.
Stratigraphic & geographic distribution. Upper Triassic (Norian–Rhaetian) of Tethys and Panthalassa and Lower Jurassic (Hettangian–Pliensbachian) of Tethys.
(Falzoni et al. (2025)). [details]
Description. Multi-chambered, trochospiral, conical test with rounded apical margin and low to moderately high, often asymmetric trochospire. The two specimens identified as Kristanita inflata (= Tetrataxis inflata) by Kristan-Tollmann (1964), in plate 7, figures 4 and 7 show that the early chambers of the first two whorls are small, globular and very slowly increasing in size (Fig. 5U, Y). Adult stage with chambers crescentic and elongated, in the third whorl rapidly increasing, in the final whorls more slowly increasing in size; the chamber height remains constant especially in the last two whorls; sutures strongly curved, oblique and keeled (Figs 4–6). On the umbilical side, 3–4 chambers in the last whorl that may be weakly concave to weakly inflated, initially subtrapezoidal–subtriangular in shape; last chamber often semicircular and occupying nearly half whorl; sutures depressed and often not visible (Figs 4–6). Umbilical cavity developed along the axis of the test from early whorls to the umbilicus (Fig. 8K), which is slightly depressed. The shape of the transverse section of the umbilical cavity changes through ontogeny depending on the number of chambers in the whorl. The section appears polygonal in early whorls (with 5–7 chambers per whorl) to square in later whorls (with 3–4 chambers per whorl) (Fig. 8Q–T). Aperture, a slit opening at the base of the apertural face in a tri- to tetralobate umbilical depression and partially covered by supplementary structures in umbilical to extra-umbilical position (Figs 4D, F, Q, S, 5F, Z). Wall simple, single-layered, finely agglutinated and dark in thin section.
Stratigraphic & geographic distribution. Upper Triassic (Norian–Rhaetian) of Tethys and Panthalassa and Lower Jurassic (Hettangian–Pliensbachian) of Tethys.
(Falzoni et al. (2025)). [details]
Hayward, B.W.; Le Coze, F.; Vachard, D.; Gross, O. (2025). World Foraminifera Database. Kristanita Falzoni, Rettori & Gale, 2025 †. Accessed at: https://www.marinespecies.org/foraminifera/aphia.php?p=taxdetails&id=1831678 on 2025-09-13
Date
action
by
original description
Falzoni, F.; Rettori, R.; Gale, L.; Mikhalevich, V. I.; Weinmann, A. E.; Parente, M. (2025). Taxonomy and palaeoecology of the Mesozoic family Duotaxidae Mikhalevich (Foraminifera). <em>Papers in Palaeontology.</em> 11(5): 1-28., available online at https://doi.org/10.1002/spp2.70032
page(s): p. 15. [details] Available for editors [request]
page(s): p. 15. [details] Available for editors
[request]From editor or global species database
Original description Diagnosis. Trochospiral, conical test with weakly concave to weakly inflated umbilical side, 3–4 elongated chambers in the last whorl, spiral sutures strongly to weakly keeled, umbilical cavity developed from early whorls to the umbilicus, which appears strongly depressed; aperture, a wide horizontal slit opening at the base of the apertural face of the last chamber in an irregularly developed tri- to tetralobate umbilical depression and with supplementary structures (‘längliche Zapfen’ in Kristan 1957) in umbilical to extra-umbilical position. Description. Multi-chambered, trochospiral, conical test with rounded apical margin and low to moderately high, often asymmetric trochospire. The two specimens identified as Kristanita inflata (= Tetrataxis inflata) by Kristan-Tollmann (1964), in plate 7, figures 4 and 7 show that the early chambers of the first two whorls are small, globular and very slowly increasing in size (Fig. 5U, Y). Adult stage with chambers crescentic and elongated, in the third whorl rapidly increasing, in the final whorls more slowly increasing in size; the chamber height remains constant especially in the last two whorls; sutures strongly curved, oblique and keeled (Figs 4–6). On the umbilical side, 3–4 chambers in the last whorl that may be weakly concave to weakly inflated, initially subtrapezoidal–subtriangular in shape; last chamber often semicircular and occupying nearly half whorl; sutures depressed and often not visible (Figs 4–6). Umbilical cavity developed along the axis of the test from early whorls to the umbilicus (Fig. 8K), which is slightly depressed. The shape of the transverse section of the umbilical cavity changes through ontogeny depending on the number of chambers in the whorl. The section appears polygonal in early whorls (with 5–7 chambers per whorl) to square in later whorls (with 3–4 chambers per whorl) (Fig. 8Q–T). Aperture, a slit opening at the base of the apertural face in a tri- to tetralobate umbilical depression and partially covered by supplementary structures in umbilical to extra-umbilical position (Figs 4D, F, Q, S, 5F, Z). Wall simple, single-layered, finely agglutinated and dark in thin section.
Stratigraphic & geographic distribution. Upper Triassic (Norian–Rhaetian) of Tethys and Panthalassa and Lower Jurassic (Hettangian–Pliensbachian) of Tethys.
(Falzoni et al. (2025)). [details]
From editor or global species database
Image from typetaxon