Cheilotrypa strunica, Tolokonnikova & Song & Zong, 2025

Tolokonnikova, Zoya A., Song, Junjun & Zong, Ruiwen, 2025, New latest Famennian (Late Devonian) cystoporate bryozoans from the Bulongguoer section, northwest Xinjiang, China, Zootaxa 5594 (2), pp. 367-376 : 372

Cheilotrypa strunica sp. nov.

( Fig. 3E–G , Table 2 )

Holotype. CNIGR museum № 1/13031 ; Bulongguoer section , upper member of the Hongguleleng Formation, Devonian (uppermost Famennian); Xinjiang, China.

Additional material. CNIGR museum № 2/13031, 3/13031, 4/13031, 5/13031, 6/13031, 7/13031, 8/13031, 9/13031, 10/13031, 11/13031; same details as for the holotype .

Etymology. The species name refers to the Strunian age of the deposits, in which bryozoans were found.

Diagnosis. Colony delicately branched with a hollow axis, which has sinuous shape. Six rows of autozooecia are arranged around the axial hollow. Single autozooecial diaphragms in exozone. Autozooecial apertures oval with proximal overhangs. Rare vesicles.

Description. Colony delicately branched with a hollow axis, which has a sinuous shape. Six rows of autozooecia are arranged around the axial hollow. Autozooecial walls 0.01 mm thick in endozones and thickened to 0.04–0.06 mm in exozone. Single autozooecial diaphragms present in exozones. Autozooecial apertures oval with proximal overhangs ( Fig. 3E, G ). Rare small vesicles in exozones, polygonal in deep tangential section, incompletely isolating autozooecia. Colony surface between apertures covered with thick layer of calcitic material, 0.06–0.10 mm in thickness. Lunaria usually poorly developed, 0.04–0.06 mm in length and 0.08–0.10 mm in width.

Remarks. Cheilotrypa strunica sp. nov. differs from C. kurganica Tolokonnikova, 2012 from the Uppermost Famennian of Kurgan area, Russia, in the lower number of rows of autozooecia surrounding the axial hollow (6 vs 7–8 in C. kurganica ), and in having smaller vesicles (0.06–0.08 mm vs 0.10–0.12 mm in C. kurganica ).Additionally, the presence of proximal overhangs beneath the autozooecial apertures is unique to this species, further setting it apart from other members of the genus Cheilotrypa .

Stratigraphical and geographical distribution. Upper member of the Hongguleleng Formation, Devonian (uppermost Famennian); Xinjiang, China.

Figures

FIGURE 3. Latest Famennian bryozoans from the Bulongguoer section.A–D Cheilotrypa gongae sp. nov. A, B and C. CNIGR museum № 12/13031. D. CNIGR museum № 13/13031. A. Longitudinal section. B. Transverse section. C. Deep tangential section showing vesicles. D. Tangential section showing bell-shaped lunaria (arrow) in autozooecial aperture. E–G. Cheilotrypa strunica sp. nov. CNIGR museum № 1/13031. E. Longitudinal section showing proximal overhangs (arrows). F. transverse section showing thick layer of calcitic skeletal material on the colony surface (arrow). G. tangential section showing proximal overhangs under autozooecial apertures (arrows).