Lingula borealis Bittner, 1899; Newell & Kummel, 1942.
Lingula sp. ind. Birkenmajer & Pugaczewska, 1975.
? Lingula aff. arctica Wittenburg, 1910; Dagys, 1965.
Lingula cf. beani Phillips, 1829; Bäckström and Nagy, 1985.

Umbonal region rounded with median beak weak on dorsal valve, pointed on ventral valve; large propareas separated by deep pedicle groove, not continuous with internal valve face.
Body muscles characterized by internal median oblique narrowing in the anterior third; internal anterior oblique scar tear-drop shaped, located near anterior oblique; and internal posterior oblique scar weak and tear-drop shaped, extending to near the posterior adductor.
Mantle canals with strong S-shaped, curves on both sides.

Lingula polaris Lundgren, 1883; Dagys, 1965.
?Lingula polariformis ex. aff. polaris Wurm, 1911.
?Lingula olenekensis Dagys, 1965.

Holotype: ZPAL Bp.XXIV/3. Type locality: Olenek River, Northern Siberia (see Dagys, 1965, p. 12). Type horizon: Middle Triassic, Anisian.
Etymology: Siberica because the specimens previously referred to polaris were collected in the northern part of Siberia.

Numerous fine radial striae and commonly concentric microlines between thicker growth lines generally visible on the shell. Umbonal region rounded on dorsal valve, pointed on ventral valve; small propareas separated by a deep and wide striated pedicle groove, not continuous with internal valve face.

Body muscles characterized by internal anterior oblique located near anterior oblique; internal posterior oblique not observed.

Mantle canals almost straight, convergent.

?Lingularia michailovae Smirnova & Ushatinskaya, 2001.
Lingularia cf. smirnovae Márquez-Aliaga et al., 1999; Márquez-Aliaga et al., 2007.

Holotype: ZPAL Bp.XXIV/14. Type locality: W Kazakhstan, Mangyshlak Peninsula, SW Karatau Mountains. Type horizon: Cretaceous, Albian.
Etymology: The name of this species is dedicated to Tatiana Smirnova (Department of Paleobiology, State University of Moscow) who kindly provided us with a large collection.

Umbonal region rounded with weak median beak on dorsal valve, pointed on ventral valve; small propareas separated by deep and narrow pedicle groove, not continuous with internal valve face.
Body muscles characterized by small internal anterior oblique located near anterior oblique and above internal posterior oblique, posterior adductor more developed on right part of ventral side and on left of dorsal.
Dorsal mantle canals strongly S-like (not observed on ventral side).

Holotype: PIN 4796/12. Type locality: Sengilei, Ul'yanovk region. Type horizon: Lower Aptien, Lower Cretaceous.
Etymology: in honor of the paleontologist Irina A. Michailova.

Shell small, up to 5 mm long, weakly uniformly biconvex, regularly oval in outline. Umbo rounded. Gently rounded lateral margins, grade into the anterior margin, posterior margin long, strongly curved, well defined from the other part of the shell. The greatest width is attained in posterior third.of the shell.

According to Smirnova & Ushatinskaya (2001): "the new species is distinct from Lingularia smirnovae Biernat & Emig, 1993 in its regularly oval shell outline, smaller size, rounded lateral commissures, location of greatest width, and narrower anterior margin. It is distinct from L similis Biernat & Emig, 1993 in its smaller size, rounded lateral margins, location of greatest width and thickness of the shell, and narrow pseudointerarea."

NOTA: all the above cited characters to distinguish species have been demontsrated as no-taxonomic characters by Biernat & Emig (1993). On the other hand, the muscle arrangement of this species and those of Lingularia smirnovae(see figures) appear rather similar.

Lingularia? bagualensis (Wilckens, 1907).
Glottidia sp. Cusack et al., 1990.
Glottidia sp. Williams et al., 2000.

Holotype: MN 8283-I . Type locality: Oiteiro, Sergipe Basin, Brazil. Type horizon: upper Turonian of the Cotinguiba Formation.
Etymology: : Latin notialis (''southern''), after the occurrence in South America.

Ventral pseudointerarea wide with small propareas separated by a wide and deep pedicle groove, level with valve floor; ventral umbonal muscle scars not bisected by groove of pedicle nerve. Dorsal pseudointerarea poorly defined, forming short, slightly thickened, crescent-shaped rim; dorsal umbonal muscle scar possibly double. Mantle canals of both valves narrow. Both valves with large lophophoral cavity occupying more than half of total valve width. Shell structure baculate.

'Lingula sp.' Bragin,1991.
Lingularia aff. lindstromi Yanagita et al., 1995.
Lingula sp. Murata, 1973.

Holotype: . Type locality: Shikoku, Japan . Type horizon: Anisian (early Middle Triassic).

Proposed by Sykora et al. (2011) - no taxonomic characters, no diagnosis - just based on a discussion.

Occurrence: West Siberia, Shirotnoe Priob’e; Upper Jurassic, transitional layers between the Abalak and Bazhenov formations.

Holotype: PIN 4898/4140, ventral valve interior. Type locality: West Siberia, Shirotnoe Priob’e. Type horizon: Upper Jurassic, transitional beds between the Abalak and Bazhenov formations.
Etymology: From the Salym River in the Shirotnoe Priob’e area, West Siberia.

The comparison with other species of Lingularia is based characters well known to have no taxonomic value:
"The new species differs from L. smirnovae Biernat et Emig, 1993 and L. similis Biernat et Emig, 1993 in the considerably smaller (almost three times), regularly oval, wider shell with rounded lateral margins. It differs from L. michailovae Smirnova, 2001 in the regularly oval shell, maximum width located in the middle of the shell, considerably larger apical angle, rounded umbo, and impunctate shell fabric." (Smirnova et al., 2015)

Nota : no diagnosis available - is in some studies names as Lingularia mytiloides (Sowerby, 1912) without any reference to the description of this species under its genus name ! See Mottequin et al. (2019) and Denov (2024). Nervertheless, this species may be a synonym of Eolingularia siberica.