Cribrospira Möller, 1878

Liu, Chao, Vachard, Daniel, Cózar, Pedro & Coronado, Ismael, 2023, New species and evolution of the foraminiferal family Janischewskinidae in the middle-upper Mississippian of South China, Palaeontologia Electronica (a 2) 26 (1), pp. 1-27 : 10-11

Genus Cribrospira Möller, 1878

Type Species. Cribrospira panderi Möller, 1878 .

Diagnosis. Globose Janischewskinidae with a marked small skew-coiled juvenarium, low number of chambers, and short septa, curved backward, with swollen extremes or straight pointed. Wall granular in the primitive species, becoming microgranular to porous in more advanced forms. Cribrate aperture in the final chamber.

Composition. Cribrospira auriculata ( Lin, 1981) , C. baliamadeni Pille, Vachard and Argyriadis in Pille et al., 2010; C. denticulata Strank, 1983 ; C. evoluta sp. nov.; C. knetschi Omara and Conil, 1966 ; C. lebedevae Vachard and Cózar in Vachard et al., 2016 (= Janischewskina ladeinaensis Stepanova and Gibshman, 2017 = Janischewskina compressa Grozdilova and Lebedeva in Grozdilova et al., 1978), C. lianxianensis Lin, 1981 ; C. micula Vdovenko, 1982 ; C. mikhailovi Rauser-Chernousova, 1948c ; C. mira Rauser-Chernousova, 1948c ; C. orbiculata ( Ganelina, 1956) ; C. panderi Möller, 1878 ; C. pansa Conil and Lys, 1965 ; C. paradenticulata sp. nov.; C. rara Rauser-Chernousova, 1948c .

Remarks. As mentioned previously, the most primitive species of the genus show a more granular wall with some agglutinated grains, and thus, they could be considered by some scholars as Rhodesinella , such as C. denticulata , C. knetschi , C. micula , C. pansa , C. paradenticulata , and C. rara . In contrast, more evolved species of the genus show a typical microgranular to porous wall (e.g., C. panderi , C. baliamadeni , and C. orbiculata ).

Occurrence. Middle Viséan to late Serpukhovian in the Russian Platform, Urals, Belgium, Spain, England, Morocco, Ireland, Poland, Southern France and Ukraine. The genus has been also described in the same interval in Turkey, “Central Asia”, China, Laos, Viet-Nam, and Japan ( Hance et al., 2011). Although as mentioned above, the First Occurrence Datum of the genus is usually in the middle Viséan or its equivalents, the First Appearance Datum ( FAD) of the most primitive species of the genus, considered as Rhodesinella auct., is in the uppermost lower Viséan in Europe, upper Moliniacian in Belgium ( Laloux, 1987), and upper Arundian in Britain ( Figure 4D‒E ; see also Fewtrell et al., 1981).

Distribution in the Bama Platform. The genus is rare below the Mikhailovian, and only Cribrospira paradenticulata has been recorded in the Bama Platform in strata equivalent to the Tulian, and Cribrospira mira ( Figure 6B ) from the upper part of the Aleksinian. The base of the Mikhailovian is marked by the first C. panderi (together with Eostaffella ikensis Vissarionova, 1948 ) ( Figure 6C ). These species are present in the entire Mikhailovian in the Shuidong section and only at the top of this substage C. orbiculata and C. mikhailovi first occur ( Figure 6A, E ). In the Kacai section, C. mikhailovi is also first recorded from the base of this substage.

More diversified species are recorded from the Venevian, including C. evoluta , C. baliamadeni , and C. lianxianensis ( Figure 6D, F ). However, this increase in the diversity does not coincide with an increase in its abundance, which is mostly concentrated in levels assigned to the Serpukhovian.

Figures

FIGURE 4. Selected primitive Janischewskinidae with granular wall or with some agglutinated grains compared with a Mstiniidae. A. Bibradya grandis Strank, 1983, DPM-PC-TQ56-1250, Urswick Limestone Formation, Trowbarrow Quarry (N. England), late Asbian (late Viséan). Microgranular wall with rare agglutinated large grains in the third and sixth septa from the aperture. B. Bibradya moldensis (Strank in Somerville and Strank, 1984), HPU-SBD179-208, Shuidong section, Protvian (late Serpukhovian). Note the granular wall, rarely with small agglutinated grains. C. Holkeria avonensis (Conil and Longerstaey in Conil et al., 1980), DPM-PC-BS68-955, Park Limestone Formation, Barker Scar section (N. England), Holkerian (middle Viséan). Granular wall throughout the test with some large agglutinated grains in septa and outer wall. D. Cribrospira pansa Conil and Lys, 1965, DPM-PC-LF26-2162, Dalton Formation, Low Frith section (N. England), ‘upper’ Arundian (lower Viséan). Microgranular wall in the inner whorls with more granular aspect in the final whorls and with common small agglutinated grains. E. Cribrospira pansa, DPM-PC-WS36-1587, Dalton Formation, White Scar Quarry (N. England), ‘top’ Arundian (middle Viséan). Microgranular wall throughout the test, with large agglutinated grains in the wall of the final chambers. F. Bibradya inflata Strank, 1983, DPM-PC-TQ84- 1954, Urswick Limestone Formation, Trowbarrow Quarry (N. England), late Asbian (upper Viséan). Microgranular wall throughout the test with some small agglutinated grains. (Scale bar equals 0.5 mm). [DPM- corresponds to the Palaeontological Collection in the Palaeontology Department of the Universidad Complutense de Madrid, PC- to the P. Cózar’s collection, the following number corresponds to the number of thin-section (e.g., TQ56, WS36, …), and the final number corresponds to the number of specimens].

FIGURE 6. A. Typical representatives of the genus Cribrospira recorded in South China. Cribrospira mikhailovi Rauser-Chernousova, 1948c, HPU-SDB140-5. B. Cribrospira mira Rauser-Chernousova, 1948c, HPU-KC10-2. C. Cribrospira panderi Möller, 1878, HPU-SDB137-3. D. Cribrospira baliamadeni Pille, Vachard and Argyriadis in Pille et al., 2010, HPU-KC66-2. E. Cribrospira orbiculata (Ganelina, 1956), HPU-SDB144-9. F. Cribrospira lianxianensis Lin, 1981, HPU-SDB147-528. G‒H. Cribrospira paradenticulata sp. nov., G. HPU-SDB114-2 (holotype), H. HPU-SDB144- 1. (Scale bar equals 1 mm, except for Figure G equals 0.5 mm).