Cheilotrypa gongae, 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 : 370

Cheilotrypa gongae sp. nov.

( Fig. 3A–D , Table 1 )

Holotype. CNIGR museum № 12/13031 ; Bulongguoer section , upper member of the Hongguleleng Formation, Devonian (uppermost Famennian); Xinjiang, China.

Additional material. CNIGR museum № 13/13031, 14/13031, 15/13031, 16/13031, 17/13031, 18/13031, 19/13031, 20/13031, 21/13031, 22/13031, 23/13031, 24/13031, 25/13031, 26/13031, 27/13031, 28/13031, 29/13031; same details as for the holotype .

Etymology. The species is named in honour of Professor Yiming Gong, who contributed greatly to the study of Devonian stratigraphy and palaeontology.

Diagnosis. Colony ramose. Single diaphragms in autozooecial chambers between exozone and endozone. Autozooecial apertures oval with poorly developed bell-shaped lunaria. Abundant vesicles in 1–3 rows between autozooecial apertures.

Description. Colony ramose, dichotomously branched.Autozooecia long, tubular, growing upright in endozone. Autozooecia bend sharply in exozone at an angle of 80°. Autozooecial walls 0.01 mm thick in endozone and 0.02 mm in exozone. Endozone is usually one-third of the colony diameter. Single autozooecial diaphragms located in autozooecial chambers between exozone and endozone. Autozooecial apertures on surfaces oval, arranged in irregular diagonal rows. Apertures with thick-walled peristomes, 0.02–0.03 mm in thickness. Bell-shaped lunaria are not expressed at every autozooecial aperture. The length of the lunaria is 0.04 mm, the width is 0.08 mm. Vesicle skeleton well developed. Vesicles located in 1–3 rows on the aperture interspaces, surrounding each autozooecial aperture. Vesicles irregularly shaped, polygonal in tangential section, sealed by 0.06 mm thick layer of calcitic skeletal material on the colony surface.

Remarks. Cheilotrypa gongae sp. nov. differs from C. plimacylindrilla ( Xia, 1997) from the Famennian of Xinjiang in the angle of autozooecia deviation in the exozone to the colony surface (80° vs 45° in C. plimacylindrilla ), the presence of single autozooecial diaphragms (absent in C. plimacylindrilla ), fewer rows of vesicles (1–3 vs 2–6 in C. plimacylindrilla ), and smaller autozooecial apertures (0.12–0.14x 0.18–0.22 mm vs 0.14–0.20x 0.23–0.28 mm in C. plimacylindrilla ).

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).