Phylum Bryozoa Ehrenberg, 1831
Class Stenolaemata Borg, 1926
Superorder Palaeostomata Ma, Buttler, and Taylor, 2014
Order Cystoporata Astrova, 1964
Suborder Fistuliporina Astrova, 1964
Family Fistuliporidae Ulrich, 1882
Genus Cystiramus Morozova, 1959
Type species
Cystiramus kondomensis Morozova, 1959. Upper Devonian (Frasnian); Kuznetsk Basin, Russia.
Diagnosis
Branched colonies; secondary overgrowths common. Autozooecia short in endozones, rounded-polygonal in transverse section; isolated by vesicular skeleton in exozones. Autozooecial apertures rounded to oval, usually arranged in regularly alternating longitudinal rows; maculae absent or poorly developed. Autozooecial diaphragms present in exozones. Lunaria in exozones, consisting of granular material, usually poorly developed. Vesicles in exozones, subquadrate blisters thickened to stereom through most of exozone. Autozooecial walls thin, granular in endozones; rapidly thickened in inner exozones (diagnosis modified after Utgaard 1983).
Remarks
Cystiramus Morozova, 1959 differs from the similar genus Fistuliramus Astrova, 1960 in the absence of vesicular skeleton in endozones and maculae as well as in poorly developed lunaria. Autozooecia in Fistuliramus are long and subcircular in transverse section of endozones, whereas autozooecia in Cystiramus are short in endozones and rounded-polygonal in transverse section. Cystiramus is similar to Fistulophragmoides Gorjunova in Gorjunova and Weis, 2003 in having short autozooecia, but Fistulophragmoides differs from Cystiramus in having large irregular vesicles in endozones.
Occurrence
Devonian – Carboniferous; Europe, Russia (Altai), China.
Cystiramus cf. kondomensis Morozova, 1959
(Figs. 2a–h and Table 1)
1959 Cystiramus kondomensis Morozova, p. 80–81, text-fig. 1.
1961 Cystiramus kondomensis Morozova, 1959 – Morozova, p. 46–47, pl. 2, fig. 4, pl. 5, fig. 1.
Table 1
Summary of descriptive statistics for Cystiramus cf. kondomensis Morozova, 1959 (single colony measured). Abbreviations: N, number of measurements; X, mean; SD, sample standard deviation; CV, coefficient of variation; MIN, minimal value; MAX, maximal value
|
N
|
X
|
SD
|
CV
|
MIN
|
MAX
|
autozooecial aperture width, mm
|
20
|
0.25
|
0.032
|
12.78
|
0.18
|
0.29
|
autozooecial aperture spacing, mm
|
20
|
0.37
|
0.042
|
11.46
|
0.30
|
0.45
|
vesicle width, mm
|
20
|
0.10
|
0.026
|
27.12
|
0.05
|
0.14
|
vesicles per aperture
|
16
|
10.2
|
2.007
|
19.70
|
8.0
|
14.0
|
vesicle spacing, mm
|
20
|
0.13
|
0.028
|
22.40
|
0.07
|
0.18
|
Material
Single colony, four thin sections GZG.IN.0.010.518a–d.
Description
Branched colony with oval shape of transverse section, consisting of successive layers. Short diameter 3.75 mm, long diameter 5.60 mm, Exozone 0.50–0.63 mm wide. Autozooecia long in endozones, having polygonal shape in transverse section. Autozooecial apertures oval; lunaria obscure. Autozooecial diaphragms present in exozones. Vesicles in exozones, subquadrate flattened blisters, polygonal in deep tangential section, completely isolating autozooecia, 8–14 surrounding each autozooecial aperture. Autozooecial walls granular, 0.003–0.005 mm thick in endozones; laminated, showing indistinct zooecial boundaries, 0.09–0.14 mm thick in exozones. Maculae consisting of vesicles, slightly elevated, 0.75–1.50 mm in diameter.
Remarks
The present material is most similar to C. kondomensis Morozova, 1959 from the Upper Devonian (Frasnian) of Kuznetsk Basin, Russia. Minor difference is observed in the number and size of vesicles. Figures in Morozova (1961, pl. 5, Fig. 1) reveal 6–11 vesicles per autozooecial aperture, whereas the present material possesses 8–14 vesicles per aperture. Vesicle width in the present material is 0.05–0.14 mm vs. 0.10–0.13 mm given by Morozova (1961, p. 47). Moreover, Morozova mentioned absence of maculae, which are present in the sample from Ferques.
Cystiramus cf. kondomensis Morozova, 1959 differs from C. multifarius Volkova, 1974 from the Upper Devonian (Frasnian) of Altai, Russia, in having only one row of vesicles between autozooecial apertures instead of 3–4 rows in the latter species.
Occurrence
Ferques Formation, Upper Devonian (Frasnian); Ferques, Boulonnais, France.
Genus Canutrypa Bassler, 1952
Canutrypa Bassler 1952, p. 382; Dessilly 1961, p. 2–3; Utgaard 1983, p. 383; Bigey 1988b, p. 301–302; 1991, p. 27; Ernst 2008, p. 332; Ernst et al. 2012: p. 2–3.
Fistuliporid Bigey 1980, pl. 56, Figs. 1, 5; 1991, p. 27.
Fistulipora Yang 1954, p. 210; Yang and Lu 1962, p. 11–12.
Type species
Canutrypa francqana Bassler, 1952. Upper Devonian, Frasnian; Ferques, France.
Diagnosis
Branched and encrusting colonies. Secondary overgrowths common. Autozooecia long, tubular, curving gently to the colony surface, having circular to oval apertures. Autozooecial diaphragms few to common, thin, straight or inclined. Lunaria poorly defined. One or rarely two hemicylindrical cystlike structures with axes perpendicular to autozooecial axis in many autozooecia in exozone, with a wall consisting of prismatic calcite crystals. Vesicles wide at the base of exozone, becoming narrow at the colony surface. Colony surface covered with a thick layer of granular skeleton (diagnosis modified after Utgaard 1983).
Remarks
Canutrypa Bassler, 1952 differs from other cystoporates in the presence of cystlike structures.
Occurrence: Two species of Canutrypa Bassler, 1952 were reported: Canutrypa francqana Bassler, 1952, from the Middle Devonian (Eifelian–Givetian) of Germany and Poland (Morozova et al. 2002); Upper Devonian (Frasnian) of France (Bassler 1952, Bigey 1980, 1985, 1988b, 1991), Belgium (Dessily 1961) and Poland (Morozova et al. 2002)d hemispheroidea (Yang, 1954) from the Wutsun Shale, Middle Devonian of Kwangsi, and Devonian of Qilianshan, both China, from the Hajigak Formation (Upper Devonian, Frasnian) of Hajigak, central Afghanistan, and Shishtu Formation (Upper Devonian, Frasnian) of Iran.
Canutrypa francqana Bassler, 1952
(Figs. 2i, 3a–d and Table 2)
Table 2
Summary of descriptive statistics for Canutrypa francqana Bassler, 1952 (single colony measured). Abbreviations as for Table 1
|
N
|
X
|
SD
|
CV
|
MIN
|
MAX
|
autozooecial aperture width, mm
|
20
|
0.26
|
0.033
|
12.90
|
0.19
|
0.34
|
autozooecial aperture spacing, mm
|
20
|
0.36
|
0.030
|
8.28
|
0.30
|
0.42
|
vesicle width, mm
|
20
|
0.09
|
0.020
|
21.57
|
0.06
|
0.14
|
vesicles per aperture
|
10
|
10.1
|
1.197
|
11.85
|
9.0
|
12.0
|
vesicle spacing, mm
|
20
|
0.07
|
0.016
|
21.87
|
0.05
|
0.10
|
1952 Canutrypa francqana Bassler, p. 382, figs 3–4.
1953 Canutrypa francqana Bassler, 1952 – Bassler, p. G 99, fig. 63 (3a–b).
1961 Canutrypa francqana Bassler, 1952 – Dessilly, p. 8–9, pl. 1, figs 1–6, pl. 2, figs 1–5.
1980 Canutrypa francqana? Bassler, 1952 – Bigey, pl. 56, fig. 6.
1980 Fistuliporid – Bigey, pl. 56, figs 1, 5.
1983 Canutrypa francqana Bassler, 1952 – Utgaard, p. 383, figs 175 (1a–e).
1985 Canutrypa francqana Bassler, 1952 – Bigey, p. 27, fig. 4H.
1988b Canutrypa francqana Bassler, 1952 – Bigey, p. 302, pl. 37, figs 13–16.
1991 Canutrypa francqana Bassler, 1952 – Bigey, p. 27, pl. 1, figs 1–8.
2002 Canutrypa francqana Bassler, 1952 – Morozova et. al.: 332–334, figs 3C–F.
2008 Canutrypa francqana Bassler, 1952 – Ernst: 309, figs 12A–G, 13A–D.
Material
Single colony GZG.IN.0.010.568a–f.
Description
Ramose colony consisting of series of encrusting sheets with secondary overgrowths; separate sheets, 0.4–1.1 mm thick. Epitheca 0.008–0.010 mm thick. Autozooecia long, tubular, growing from a thin epitheca, curving gently to the colony surface, having circular to oval apertures. Autozooecial diaphragms few to common, thin, straight or inclined. Lunaria indistinct. Vesicles polygonal in cross section, wide at the base of exozone, becoming narrow at colony surface, sealed by granular skeleton at colony surface, 9–12 surrounding each autozooecial aperture. Colony surface covered with thick layer of granular skeleton. Maculae flat, consisting of vesicular skeleton. One hemicylindrical cystlike structure in many autozooecia in exozone, positioned directly on distal autozooecial walls. Cyst wall consisting of prismatic calcite crystals, 0.010–0.015 mm thick. Autozooecial walls granular, 0.003–0.005 mm thick in endozones; laminated, showing indistinct zooecial boundaries, 0.025–0.035 mm thick in exozones.
Remarks
Canutrypa francqana Bassler, 1952 differs from C. hemispheroidea (Yang, 1954) from the Wutsun Shale, Middle Devonian of Kwangsi, China, in having smaller autozooecial apertures (average aperture width 0.26 mm vs. 0.33 mm in C. hemispheroidea) and in having less abundant vesicles (averagely 10.1 vesicles per aperture vs. 13.4 in C. hemispheroidea). Measurements for C. hemispheroidea (Yang, 1954) are from Ernst et al. (2012).
Occurrence
Ferques Formation, Upper Devonian (Frasnian); southwestern part of the quarry „les Parisennes“, Boulonnais, France. Junkerberg Formation, Grauberg Subformation, lowermost Latistriatus Member, Eifelian, Middle Devonian; Railway cut west of Blankenheim, Blankenheim syncline, Eifel (western Rhenish Massif; locality 1). Honsel and Werdohl Formations (Givetian, Middle Devonian); Lüdenscheid, eastern Rhenish Massif. Uppermost Givetian – lowermost Famennian, Middle to Late Devonian; Poland.
Order Trepostomata Ulrich, 1882
Suborder Amplexoporidae Astrova, 1965
Family Stenoporidae Waagen and Wenzel, 1886
Genus Dyoidophragma Duncan, 1939
[= Pseudocampylus Troitzkaya, 1960]
1939 Duncan, p. 240.
1939 Dyoidophragma Duncan, p. 240.
1960 Duncan, – Boardman, p. 41.
1960 Dyoidophragma Duncan, 1939 – Boardman, p. 41.
1960 Troitzkaya, p. 258.
1960 Pseudocampylus Troitzkaya, p. 258.
1968 Troitzkaya, – Troitzkaya, p. 112.
1968 Pseudocampylus Troitzkaya, 1960 – Troitzkaya, p. 112.
1997 Troitzkaya, – Xia, p. 107.
1997 Pseudocampylus Troitzkaya, 1960 – Xia, p. 107.
Type species
D. typicale Duncan, 1939, p. 241, Gravel Point stage, Traverse group (M. Devonian), abandoned quarry, about ¾ mile west of Charlevoix city line, Michigan, USA.
Diagnosis (emended): Colonies encrusting or dendroid, maculae indicated by macrozooecia, some with clusters of large styles (Fig. 5a), others with central cluster of exilazooecia surrounded by macrozooecia. In endozones: in encrusting colonies, budding interzooidal, endozones restricted to recumbent buds, autozooecia rhombic in arrangement. In dendroid colonies, endozones non-uniform, axial autozooecia large, irregularly polygonal in cross section. Some large axial autozooecia split intrazooidaly into more than one peripheral autozooecium. Peripheral autozooecia reduced in size, polygonal in cross section, irregularly rhombic in pattern, no diaphragms, wall thickening to exozone gradual. In exozones: autozooecial surface angles high in dendroid colonies. Autozooecial boundaries polygonal, broadly merged. Autozooecia irregularly rhombic in arrangement on colony surfaces, walls regular in thickness, no cingulum. Diaphragms in autozooecia lacking to rare and thin, unilateral, some secondary from ends of hemiphragms. Hemiphragms on proximal walls only, generally evenly spaced in ontogenetic sequences, some few irregularly spaced, many calcified on both sides (Fig. 5b). Exilazooecia rare to common, some with one or two diaphragms widely and irregularly spaced. Between maculae styles few and small in dendroid species, in encrusting species common, centred or off-centred from autozooecial boundaries.
Remarks
Pseudocampylus Troitzkaya, 1960, has a dendroid type species comparable generically to encrusting Dyoidophragma species. Some confusion arose when Astrova (1978, p. 136) made Pseudocampylus a junior subjective synonym of Tabuliporella Nikiforova, 1933, and illustrated Tabuliporella with the type species of Pseudocampylus (pl. 33, Fig. 1). Tabuliporella differs from both Pseudocampylus and Dyoidophragma by having hemiphragms alternating in ontogenetic sequence from both proximal and distal walls of autozooecia producing a different shaped living chamber for polypides.
Occurrence
Middle Devonian (Givetian); USA (Michigan, New York). Upper Devonian (Famennian); Kazakhstan, China. Upper Devonian (Frasnian); France.
Dyoidophragma bigeye n. sp.
(Figs. 3e–f, 4a–h and Table 3)
Table 3
Summary of descriptive statistics for Dyoidophragma bigeye n. sp. (ten colonies measured). Abbreviations as for Table 1
|
N
|
X
|
SD
|
CV
|
MIN
|
MAX
|
branch width, mm
|
10
|
1.3
|
0.379
|
29.42
|
1.0
|
1.9
|
exozone width, mm
|
10
|
0.4
|
0.157
|
41.27
|
0.2
|
0.6
|
endozone width, mm
|
10
|
0.5
|
0.077
|
14.67
|
0.4
|
0.6
|
axial ratio
|
10
|
0.43
|
0.072
|
16.87
|
0.33
|
0.53
|
autozooecial aperture width, mm
|
30
|
0.09
|
0.011
|
12.18
|
0.07
|
0.11
|
autozooecial aperture spacing, mm
|
30
|
0.18
|
0.024
|
13.31
|
0.14
|
0.23
|
acanthostyle diameter, mm
|
30
|
0.032
|
0.005
|
14.93
|
0.025
|
0.040
|
exilazooecia width, mm
|
30
|
0.035
|
0.014
|
39.01
|
0.015
|
0.075
|
hemiphragm spacing, mm
|
20
|
0.09
|
0.017
|
18.45
|
0.06
|
0.12
|
exozonal wall thickness, mm
|
20
|
0.06
|
0.021
|
38.71
|
0.03
|
0.10
|
1988b Rhombopora cf. hemiseptata Morozova, 1961 – Bigey, 314, pl. 39, Fig. 6–9.
Etymology
The species is named in honour of Françoise P. Bigey, who contributed greatly to study of Devonian bryozoans.
Holotype
GZG.IN.0.010.567e.
Paratypes
GZG.IN.0.010.530a–i, GZG.IN.0.010.567a–d, f–i.
Type locality
southwestern part of the quarry „les Parisennes“, Boulonnais, France.
Type horizon
Ferques Formation, Upper Devonian (Frasnian).
Diagnosis
Branched colonies with distinct exozones; encrusting overgrowths rare; autozooecia tubular-prismatic, with rounded-polygonal apertures; basal diaphragms common to abundant, restricted to exozone; abundant hemiphragms on proximal walls in exozones; autozooecial walls granular in endozone; laminated, merged in exozones; exilazooecia common to abundant; acanthostyles abundant; maculae absent; macrozooecia present.
Description
Branched colonies, 1.0–1.9 mm in diameter, with 0.2–0.6 mm wide exozones and 0.4–0.6 mm wide endozones. Axial ratio is 0.33–0.53. BSI is equal 26.7. Exozones distinctly separated from endozones. Encrusting overgrowths rare, 0.25–0.28 mm in thickness. Autozooecia tubular-prismatic, growing parallel to branch axes in endozone, bending abruptly in exozones. Autozooecial apertures rounded-polygonal. Basal diaphragms common to abundant, some attached to the ends of hemiphragms (e.g. Figure 3f), restricted to exozone, straight or slightly curved distally, thin. Hemiphragms abundant in exozones, positioned on proximal wall, moderately thin, short to moderately long, straight to weakly curved proximally. Autozooecial walls granular, 0.015–0.020 mm thick in endozone; laminated, merged, 0.03–0.10 mm thick in exozones. Exilazooecia common to abundant, small, polygonal, originating in basal exozone. Acanthostyles abundant, having distinct cores and laminated sheaths, originating in basal exozone. Maculae absent. Macrozooecia present, 0.13–0.17 mm in width.
Remarks
The species described by Bigey (1988b, p. 314) as Rhombopora cf. hemiseptata Morozova, 1961 from the Upper Devonian of France is herein assigned to the trepostome genus Dyoidophragma. The species Rhombopora hemiseptata Morozova, 1961 was originally described from the Upper Devonian (Frasnian) of Russia. It was later placed in the cryptostome genus Bigeyella Morozova and Weiss in Morozova et al., 2006 (Morozova et al. 2006, p. 536). This assignment appears questionable because the type species Bigeyella sparsa does not have real hemisepta (holotype PIN 4873/119). In contrast, Rhombopora hemiseptata has multiple hemiphragms positioned on the proximal walls of autozooecia. Moreover, this species possesses spherules in the autozooecial walls of exozone and rare acanthostyles. The taxonomic position of Rhombopora hemiseptata remains dubious. Superficially, it has similarities with the trepostome genus Eifelipora Ernst, 2008. Study of the type material of Rhombopora hemiseptata is needed.
Dyoidophragma bigeye n. sp. differs from D. virgata (Troitzkaya, 1960) from the Upper Devonian (Famennian) of Kazakhstan in having thinner branches (branch diameter 1.0–1.9 mm vs. 1.85–4.72 mm in D. virgata) as well as in less abundant exilazooecia. Dyoidophragma bigeye n. sp. differs from D. tarbagataica (Troitzkaya, 1960) from the Upper Devonian (Famennian) of Kazakhstan in having smaller autozooecial apertures (aperture width 0.07–0.11 mm vs. 0.12–0.16 mm in D. tarbagataica).
Order Fenestrata Elias and Condra, 1957
Suborder Fenestellina Astrova and Morozova, 1956
Family Fenestellidae King, 1849
Genus Hemitrypa Phillips, 1841
Type species
Hemitrypa oculata Phillips, 1841. Devonian; Barton, South Devon, England.
Diagnosis
Reticulate colonies, conical or fan-shaped, planar or longitudinally pleated, frontal surface exterior if conical. Branches intermediate in width, linear to moderately sinuous, closely or intermediately spaced, dichotomously divided. Two rows of autozooecia per branch, increasing to four rows proximal of branch bifurcations in some species; low straight to sinuous central keel on obverse side of branch with high nodes, composed of core of granular skeleton and sheath of laminar skeleton. Laminar wall extensions of keel nodes fused together forming a fine meshwork of polygonal openings, each opening centred over a zooecial aperture in the branch below. Axial wall between autozooecial rows zigzag in tangential sections; zooecia not strongly inflated laterally, commonly quadrangular or pentagonal in tangential section deep within endozone, less commonly elongate triangular or semicircular, pentagonal to bean-shaped in shallower endozone; maximum diameter of zooecia corresponds with either length or height; transverse walls at intermediate or high angle to reverse wall; superior hemisepta absent or weakly developed, other interior structures absent. Small- to large-diameter distal tube typically short, opening frontally or slightly inclined laterally and perhaps distally; apertural peristome present or absent; terminal diaphragms planar where present, with central boss in some species. Heterozooecia are isolated zooecia with enlarged endozonal chambers (?gynozooecia) present in proximal parts of colonies, or spherically inflated distal tubes with diameters greater than branch width (? brood chambers). Zooecial walls of granular material that may be absent on obverse side near apertures; laminar extrazooecial skeleton traversed by small to moderate microstyles (modified after F. K. McKinney, pers. comm. 2007).
Remarks
Hemitrypa Phillips, 1841 is similar to Pseudounitrypa Nekhoroshev, 1926, but differs from it in the composition of the superstructure. The superstructure of Hemitrypa is produced by laminar wall extensions of keel nodes forming a meshwork of polygonal openings which are centred over zooecial apertures in the branch below, whereas openings in Pseudounitrypa are centred over the branches and terminate laterally over the centres of the fenestrules where the superstructural elements from adjacent branches meet and fuse.
Occurrence
Lower Devonian – Upper Carboniferous; worldwide.
Hemitrypa sp.
(Figs. 6a–i and Table 4)
Table 4
Summary of descriptive statistics for Hemitrypa sp. (single colony measured). Abbreviations as for Table 1
|
N
|
X
|
SD
|
CV
|
MIN
|
MAX
|
branch width, mm
|
5
|
0.30
|
0.035
|
11.72
|
0.26
|
0.34
|
dissepiment width, mm
|
15
|
0.29
|
0.041
|
13.96
|
0.22
|
0.35
|
fenestrule width, mm
|
15
|
0.18
|
0.022
|
12.49
|
0.14
|
0.21
|
fenestrule length, mm
|
15
|
0.41
|
0.044
|
10.63
|
0.36
|
0.51
|
distance between branch centres, mm
|
10
|
0.43
|
0.055
|
12.93
|
0.38
|
0.52
|
distance between dissepiment centres, mm
|
10
|
0.72
|
0.029
|
4.05
|
0.65
|
0.75
|
autozooecial aperture width, mm
|
8
|
0.08
|
0.008
|
10.27
|
0.07
|
0.09
|
autozooecial aperture spacing along branch, mm
|
8
|
0.26
|
0.023
|
8.83
|
0.22
|
0.3
|
apertures per fenestrule length
|
10
|
2.6
|
0.516
|
19.86
|
2.0
|
3.0
|
maximum chamber width, mm
|
10
|
0.13
|
0.009
|
7.25
|
0.12
|
0.15
|
superstructure opening diameter, mm
|
10
|
0.16
|
0.016
|
10.20
|
0.13
|
0.18
|
Material
Single colony, tangential thin section GZG.IN.0.010.569a.
Exterior description
Reticulate colonies with straight branches joined by dissepiments. Autozooecia arranged in two alternating rows on branches, having circular apertures with low peristomes, 2–3 spaced per length of a fenestrule. Peristomes smooth. Fenestrules oval to rectangular, varying in size. Openings in the superstructure irregularly shaped, rounded to petaloid, corresponding to positions of apertures, 0.13–0.18 mm in diameter. Internal granular skeleton continuous with obverse keel, nodes, peristome and across dissepiments. Outer lamellar skeleton well developed. Reverse colony surface containing large, irregularly sized nodes, 0.03–0.10 mm in diameter. Apparent gynozooecia produced by two fused autozooecia at places of branch bifurcation occurring, 0.21–0.28 mm in width (Fig. 6g–i). Mutual wall of fused zooecial chambers in gynozooecia partly dissolved.
Interior description
Autozooecia pentagonal in mid tangential section; low and elongated, with short vestibule in longitudinal section. Axial wall between autozooecial rows zigzag in tangential sections; aperture positioned at distal end of chamber. Hemisepta absent.
Remarks
The present material is similar to Hemitrypa bayanaulensis Troitzkaya, 1968 from the Late Devonian (Frasnian) of Kazakhstan. It differs in having longer fenestrules (0.36–0.51 mm vs. 0.33–0.37 mm in H. bayanaulensis). The present species differs from Hemitrypa devonica Nekhoroshev, 1926 from the Middle to Upper Devonian (Givetian–Frasnian) of Kazakhstan and Russia (Altai) in having longer fenestrules (0.36–0.51 mm vs. 0.37–0.42 mm in H. devonica), wider dissepiments (0.22–0.35 mm vs. 0.12–0.18 mm in H. devonica) as well as in larger opening of the superstructure (0.13–0.16 mm vs. 0.08–0.12 mm in H. devonica).
Occurrence
Ferques Formation, Upper Devonian (Frasnian); southwestern part of the quarry „les Parisennes“, Boulonnais, France.
Family Reteporininae Dunaeva and Morozova, 1975
Genus Anastomopora Simpson, 1897
[= Reteporidra Nickles and Bassler, 1900]
Type species
Fenestella cinctuta Hall, 1884. Middle Devonian (Erian); Canada and USA.
Diagnosis
Fan-shaped colonies, some with heavy extrazooidal calcification covering proximal portion of colony; branches broad, strongly sinuous, bifurcating, branch spacing and anastomoses at intermediate distance; keels and superstructure absent; autozooecia arranged in 2–8 rows on branches, large-end intermediate-sized, elongate perpendicular to curved obverse surface, chambers nearly circular oval in tangential section deep in endozone, elongate oval in shallower endozone; transverse wall at high angle to reverse wall; hemisepta and diaphragms absent; elevated peristome present in well preserved specimens. Tubes connecting the endozonal zooecial chambers with the obverse surface present, few or abundant, varying in size. Autozooecial walls of thick granular material may be lined by laminar skeleton in both the distal tube and the inflated chamber; reverse wall flat or minimally curved transversely, longitudinal ridges on reverse side minimally developed; extrazooidal skeleton finely laminated, traversed by closely spaced small microstyles, a gently sloped median keel commonly present on reverse surface, locally forming cystose structures bridging fenestrules where broad expanse of extrazooidal skeleton is deposited as continuous sheet over multiple branches (modified after McKinney, pers. comm. 2007).
Remarks
Anastomopora Simpson, 1897 differs from the similar genus Reteporina d'Orbigny, 1849 in having more than 2 rows of autozooecia on branches. Both genera possess exozonal tubes, which number and size are variable in different species.
Occurrence
Lower – Upper Devonian; North America, Europe, Asia.
Anastomopora inflata (Bigey, 1988b)
(Figs. 7a–f and Table 5)
1988b Reteporidra inflata Bigey – 312, pl. 39, figs. 3–5.
2007 Reteporidra inflata Bigey, 1988 – Ernst and Schroeder, p. 224, figs. 10B–E.
2015 Anastomopora inflata (Bigey, 1988) – Ernst, Tolokonnikova, and Denayer, p. 14, pl. 5, figs. 4–8.
Table 5
Summary of descriptive statistics for Anastomopora inflata (Bigey, 1988b) (single colony measured). Abbreviations as for Table 1
|
N
|
X
|
SD
|
CV
|
MIN
|
MAX
|
branch width, mm
|
15
|
0.42
|
0.038
|
8.92
|
0.36
|
0.48
|
dissepiment width, mm
|
15
|
0.41
|
0.059
|
14.16
|
0.35
|
0.55
|
fenestrule width, mm
|
15
|
0.27
|
0.040
|
14.93
|
0.19
|
0.34
|
fenestrule length, mm
|
15
|
0.63
|
0.102
|
16.22
|
0.47
|
0.80
|
distance between branch centres, mm
|
15
|
0.67
|
0.073
|
10.79
|
0.58
|
0.82
|
distance between dissepiment centres, mm
|
15
|
1.01
|
0.085
|
8.44
|
0.85
|
1.15
|
autozooecial aperture width, mm
|
25
|
0.076
|
0.005
|
6.70
|
0.070
|
0.080
|
autozooecial aperture spacing along branch, mm
|
25
|
0.26
|
0.022
|
8.48
|
0.24
|
0.32
|
aperture spacing diagonally, mm
|
25
|
0.21
|
0.017
|
8.38
|
0.18
|
0.24
|
apertures per fenestrule length
|
20
|
3.9
|
0.366
|
9.52
|
3.0
|
4.0
|
maximum chamber width, mm
|
25
|
0.13
|
0.010
|
7.70
|
0.11
|
0.14
|
Material: GZG.IN.0.010.567i, GZG.IN.0.010.571a, GZG.IN.0.010.530c, g, i.
Exterior description
Reticulate colonies of unknown shape, composed of undulating, relatively wide branches and joined by long and narrow dissepiments. Branches oval to trapezoid in transverse section. Fenestrules circular to oval. Autozooecia arranged in 3 to 4 rows, after the bifurcation usually in 2 rows on the branches on the branches. Autozooecial apertures circular with high peristome, 3–4 spaced per length of a fenestrule. Microstyles on the reverse surface common, irregularly and densely spaced, originating from inner granular skeleton, 0.005–0.008 mm in diameter.
Interior description
Autozooecial chambers relatively short, deep, displaying rhombic to hexagonal shape and pentagonal (semi-hexagonal) in mid tangential section; elongate parallel to branch length; aperture positioned at distal to distoabaxial end of chamber; with moderately long vestibule. Hemisepta absent. Tubes connecting endozonal zooecial chambers with the obverse surface present, 5–7 spaced between adjacent apertures, 0.010–0.018 mm in diameter. Heterozooecia are apparent brood chambers represented by enlarged zooecia, rounded to oval in mid tangential section, situated on branches near dissepiments, 0.17–0.20 mm wide. Inner granular skeleton variable in thickness, usually well developed, continuous in nodes and microstyles. Extrazooidal skeleton finely laminated, well developed on reverse side.
Remarks
Anastomopora inflata (Bigey, 1988b) is similar to A. stellata (Krasnopeeva, 1935) from the Upper Devonian (Frasnian) of Altai. It differs in having larger fenestrules (fenestrule width 0.19–0.34 mm vs. 0.23–0.29 mm in A. stellata; fenestrule length 0.47–0.80 mm vs. 0.61–0.72 mm in A. stellata). Moreover, the latter species possesses stellate apertures which were not observed in A. inflata. Anastomopora inflata (Bigey, 1988b) differs from A. cf. quebecensis Fritz, 1938 from the Upper Devonian (Frasnian) of Iran (Ernst et al., 2012) in having narrower branches (average branch width 0.42 vs. 0.67 mm in A. cf. quebecensis), smaller fenestrules (average fenestrule width 0.27 mm vs. 0.52 mm in A. cf. quebecensis; fenestrule length 0.63 mm vs. 0.80 mm in A. cf. quebecensis), as well as in more autozooecial apertures per fenestrule length (3–4 vs. 4–7 in A. cf. quebecensis).
Occurrence
Ferques Formation, Upper Devonian (Frasnian); southwestern part of the quarry „les Parisennes“, Boulonnais, France. Middle Devonian (Givetian); Germany.