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Chiropteridium
From Fensome et al., 2019:
Chiropteridium, Gocht, 1960, p.221.
Emendation: Fensome et al., 2016b, p.34.
Taxonomic junior synonym: Galea Maier (an illegitimate name), by implication in Sarjeant (1983, p.108), who transferred the "type species" of
Galea, Galea galea, to Chiropteridium.
Taxonomic junior synonym: Membranophoridium, according to Brosius (1963, p.47) and Schindler (1992, p.202) -- however, Lentin and Williams (1993, p.421) retained Membranophoridium.
Type: Gocht, 1960, pl.17, fig.1, as Chiropteridium lobospinosum.
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Original description: [Gocht, 1960]: (Translation: Stover and Evitt, 1978, p. 26-27):
Diagnosis:
Body rounded, flattened, consisting of two membrane layers: the outer layer - which forms the appendages - very delicate, faintly fibrous, here and there with rounded perforations; inner layer of variable thickness, structureless. Processes within the individual variously shaped: in part slim; in part laminar, flap-like and distally divided by indentations. Laminar appendages often arranged into rows which connect the poles and run predominantly parallel to the lateral edge, whilst the middle surfaces remain free or bear smaller processes. Poles generally marked by single apical process and several antapical ones. All processes are hollow proturberances of the outer membrane. The shells open themselves through a tear lying perpendicular to the longitudinal axis under the apex, in the upper third of the main body.
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Modified description:
Stover and Evitt 1978, p. 26-27:
Synopsis:
Cysts skolochorate, body lenticular; processes isolated or connected proximally, and absent or greatly reduced in size and number on ventral surface; archeopyle apical, Type tA; parasulcal notch offset.
Description:
Shape: Body lenticular, outline of cysts irregular.
Wall relationships: Endophragm and periphragm appressed between isolated processes.
Wall features: No parasutural features. Processes tend to margin dorsal and ventral surfaces; middorsal surface with isolated processes or partly connected longitudinal rows of processes; connections between processes proximal; apical and antapical processes may be longer than others;
processes absent or reduced in size and number ventrally. Periphragm smooth to faintly ornamented.
Paratabulation: Poorly and incompletely indicated by occasional alignment of processes and by archeopyle; formula unknown.
Archeopyle: Apical, Type tA; principal archeopyle suture zigzag; parasulcal notch offset; operculum free.
Paracingulum: Vaguely indicated by absence of processes, rarely by transverse alignment of slender processes.
Parasulcus: Position of apical end indicated by parasulcal notch, otherwise not expressed.
Size: Intermediate to large.
Affinities:
Chiropteridium differs from Membranophoridium mainly in the kind of structures formed along the marginal areas of the body. In Chiropteridium, proximally connected and occasionally isolated processes are formed with complexly branched and/or irregularly incised distal ends. Consequently, the cysts have a highly irregular, often jagged outline. In Membranophoridium, elongate somewhat narrow sack-like structures are formed with even, curved, or slightly sinuous distal margins. The outline of the cysts, therefore, is not interrupted or broken by numerous angular indentations. Slender, isolated processes may occur on the middorsal and midventral surfaces on some forms of Chiropteridium; such processes are apparently not present on Membranophoridium.
Chiropteridium, Gocht, 1960, p.221.
Emendation: Fensome et al., 2016b, p.34.
Taxonomic junior synonym: Galea Maier (an illegitimate name), by implication in Sarjeant (1983, p.108), who transferred the "type species" of
Galea, Galea galea, to Chiropteridium.
Taxonomic junior synonym: Membranophoridium, according to Brosius (1963, p.47) and Schindler (1992, p.202) -- however, Lentin and Williams (1993, p.421) retained Membranophoridium.
Type: Gocht, 1960, pl.17, fig.1, as Chiropteridium lobospinosum.
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Gocht, 1960]: (Translation: Stover and Evitt, 1978, p. 26-27):
Diagnosis:
Body rounded, flattened, consisting of two membrane layers: the outer layer - which forms the appendages - very delicate, faintly fibrous, here and there with rounded perforations; inner layer of variable thickness, structureless. Processes within the individual variously shaped: in part slim; in part laminar, flap-like and distally divided by indentations. Laminar appendages often arranged into rows which connect the poles and run predominantly parallel to the lateral edge, whilst the middle surfaces remain free or bear smaller processes. Poles generally marked by single apical process and several antapical ones. All processes are hollow proturberances of the outer membrane. The shells open themselves through a tear lying perpendicular to the longitudinal axis under the apex, in the upper third of the main body.
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Modified description:
Stover and Evitt 1978, p. 26-27:
Synopsis:
Cysts skolochorate, body lenticular; processes isolated or connected proximally, and absent or greatly reduced in size and number on ventral surface; archeopyle apical, Type tA; parasulcal notch offset.
Description:
Shape: Body lenticular, outline of cysts irregular.
Wall relationships: Endophragm and periphragm appressed between isolated processes.
Wall features: No parasutural features. Processes tend to margin dorsal and ventral surfaces; middorsal surface with isolated processes or partly connected longitudinal rows of processes; connections between processes proximal; apical and antapical processes may be longer than others;
processes absent or reduced in size and number ventrally. Periphragm smooth to faintly ornamented.
Paratabulation: Poorly and incompletely indicated by occasional alignment of processes and by archeopyle; formula unknown.
Archeopyle: Apical, Type tA; principal archeopyle suture zigzag; parasulcal notch offset; operculum free.
Paracingulum: Vaguely indicated by absence of processes, rarely by transverse alignment of slender processes.
Parasulcus: Position of apical end indicated by parasulcal notch, otherwise not expressed.
Size: Intermediate to large.
Affinities:
Chiropteridium differs from Membranophoridium mainly in the kind of structures formed along the marginal areas of the body. In Chiropteridium, proximally connected and occasionally isolated processes are formed with complexly branched and/or irregularly incised distal ends. Consequently, the cysts have a highly irregular, often jagged outline. In Membranophoridium, elongate somewhat narrow sack-like structures are formed with even, curved, or slightly sinuous distal margins. The outline of the cysts, therefore, is not interrupted or broken by numerous angular indentations. Slender, isolated processes may occur on the middorsal and midventral surfaces on some forms of Chiropteridium; such processes are apparently not present on Membranophoridium.