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Hapsidopalla
From Williams et al., 2017:
[Hapsidopalla, Playford, 1977, p. 25. Emendation: Wicander and Wood, 1981, p.42–43.
Acritarch genus.
Type species: originally as Micrhystridium sannemannii, Deunff, 1957 (fig.1 - p.13)] ; Hapsidopalla sannemannii, emend. Playford, 1977
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Original description: [Playford,1977, p. 25]:
Genus Hapsidopalla gen. nov.
Diagnosis. Vesicle hollow, apparently single-layered, originally spherical to ellipsoidal; outline circular to subcircular or oval, clearly differentiated from processes. Numerous, ± evenly spaced, hollow, essentially homomorphic and smooth processes project from vesicle wall and branch distally; tips closed. Though discrete from one another, adjacent processes are interconnected proximally by muri that form a distinct ±uniform reticulum sculpturing the vesicle surface; processes characteristically project from junctions of muri, never from lacunae. Lacunae typically triangular to polygonal. Ihterior of processes in free communication with vesicle cavity. Excystment by splitting of vesicle wall.
Name derivation. Gr., hapsidos, meshed, netted; Gr., palla, ball. Gender feminine.
Type species (here designated). Hapsidopalla sannemannii
(Deunff) comb, nov., emend.; described below.
Other species. 1. Hapsidopalla exornata (Deunff) comb. nov., emend. ; described below.
2. Hapsidopalla reticulafa (Pothe de Baldis) comb. nov.
Basionym: Tylotopalla reticulafa Pothe de Baldis, 1975 (1975a, p. 500, 503; PI. 2, figs. 4, 6). Occurrence: Middle Silurian (Wenlock); San Juan Province, Argentina.
3. Hapsidopalla venusta (Sannemann) comb. nov.
Basionym: Hystrichosphaeridiunz venustlrm Sannemann, 1955 (p. 345; PI. 5, figs. Ila, I lb; Fig. 15). Occurrence: Middle Devonian (upper Givetian); Schiibelebene, Frankenwald, Germany.
Comparison. Insofar as the species here allocated to Hapsidopalla gen. nov. display ± equifurcate distal termini to the processes, the genus is closely comparable to Ammonidium Lister, 1970 (p. 48-49). However, the chief difference between the two genera lies in the character of the vesicle wall sculpture: viz. reticulate in Hapsidopalla vs. smooth to granulate or rugulate in Ammonidium. Vesicle sculpturing also serves to distinguish the new genus from Tylotopalla Loeblich, 1970 (p. 737: granulate, rugulate, scabrate) and Diaphorochroa Wicander, 1974 (p. 18 : granulate). The vesicle of Acriora Wicander, 1974 (p. 15-16) has corrugate-foveolate, not reticulate, sculpture; moreover the process interiors do not communicate with the vesicle cavity as they freely do in Hapsidopalla.
The type species of Pterosphaerula Cramer, 1967, P. astrala Cramer, 1967 (p. 29-30; PI. 2, fig. 20), has a reticulate sculpture on its 'central body' that is somewhat similar to the overall reticulation of Hapsidopalla specimens. However, Cramer's form possesses only simple (nonfurcate) suprareticulate protrusions; further, its central body is circumscribed by a psilate lamellar structure.
[Hapsidopalla, Playford, 1977, p. 25. Emendation: Wicander and Wood, 1981, p.42–43.
Acritarch genus.
Type species: originally as Micrhystridium sannemannii, Deunff, 1957 (fig.1 - p.13)] ; Hapsidopalla sannemannii, emend. Playford, 1977
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Original description: [Playford,1977, p. 25]:
Genus Hapsidopalla gen. nov.
Diagnosis. Vesicle hollow, apparently single-layered, originally spherical to ellipsoidal; outline circular to subcircular or oval, clearly differentiated from processes. Numerous, ± evenly spaced, hollow, essentially homomorphic and smooth processes project from vesicle wall and branch distally; tips closed. Though discrete from one another, adjacent processes are interconnected proximally by muri that form a distinct ±uniform reticulum sculpturing the vesicle surface; processes characteristically project from junctions of muri, never from lacunae. Lacunae typically triangular to polygonal. Ihterior of processes in free communication with vesicle cavity. Excystment by splitting of vesicle wall.
Name derivation. Gr., hapsidos, meshed, netted; Gr., palla, ball. Gender feminine.
Type species (here designated). Hapsidopalla sannemannii
(Deunff) comb, nov., emend.; described below.
Other species. 1. Hapsidopalla exornata (Deunff) comb. nov., emend. ; described below.
2. Hapsidopalla reticulafa (Pothe de Baldis) comb. nov.
Basionym: Tylotopalla reticulafa Pothe de Baldis, 1975 (1975a, p. 500, 503; PI. 2, figs. 4, 6). Occurrence: Middle Silurian (Wenlock); San Juan Province, Argentina.
3. Hapsidopalla venusta (Sannemann) comb. nov.
Basionym: Hystrichosphaeridiunz venustlrm Sannemann, 1955 (p. 345; PI. 5, figs. Ila, I lb; Fig. 15). Occurrence: Middle Devonian (upper Givetian); Schiibelebene, Frankenwald, Germany.
Comparison. Insofar as the species here allocated to Hapsidopalla gen. nov. display ± equifurcate distal termini to the processes, the genus is closely comparable to Ammonidium Lister, 1970 (p. 48-49). However, the chief difference between the two genera lies in the character of the vesicle wall sculpture: viz. reticulate in Hapsidopalla vs. smooth to granulate or rugulate in Ammonidium. Vesicle sculpturing also serves to distinguish the new genus from Tylotopalla Loeblich, 1970 (p. 737: granulate, rugulate, scabrate) and Diaphorochroa Wicander, 1974 (p. 18 : granulate). The vesicle of Acriora Wicander, 1974 (p. 15-16) has corrugate-foveolate, not reticulate, sculpture; moreover the process interiors do not communicate with the vesicle cavity as they freely do in Hapsidopalla.
The type species of Pterosphaerula Cramer, 1967, P. astrala Cramer, 1967 (p. 29-30; PI. 2, fig. 20), has a reticulate sculpture on its 'central body' that is somewhat similar to the overall reticulation of Hapsidopalla specimens. However, Cramer's form possesses only simple (nonfurcate) suprareticulate protrusions; further, its central body is circumscribed by a psilate lamellar structure.