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Sumatradinium hispidum
Sumatradinium hispidum (Drugg, 1970a, p.120–121, figs.12–14 [not fig.15]) Lentin and Williams, 1976, p.77. Emendation: Lentin et al., 1994, p.571, as Sumatradinium hispidum.
Originally Xenicodinium, subsequently (and now) Sumatradinium.
Holotype: Drugg, 1970, fig.12; Lentin et al., 1994, pl.1, fig.1
Paratypes: Drugg, 1970, figs.13-14; Lentin et al., 1994, pl.1, fig.2
Locus typicus: Rupat Island, Sumatra, Indonesia
Stratum typicum: Middle Miocene to Pliocene
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999
Sumatradinium hispidum (Drugg, 1970a) Lentin and Williams, 1976. This species has short, up to 5 µm, closed, spine-like processes, which are acuminate distally and commonly penitabulate or possibly sutural. Size: body length 81-99 µm, width 74-97 µm. Maximum length of processes 3-4 µm.
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Original description: Drugg, 1970, p. 121: Xenicodinium hispidum
Tract flattened dorso-ventrally, rounded pentagonal in outtline. Wall single layered, thin, finely granulate. Trapezoidal six sided intercalary archeopyle on the dorsal epitract. The operculum separates first on the lower edges similar to the mode of opening of Wetzeliella. The tract is ornamented by processes 3 µm to 5 µm long. These are hollow and usually pointed distally but occasionally exhibiting blunt to slightly capitate morphology. The density of process distribution is varriable with some specimens having fewer processes than the illustrated examples.
Dimensions: Tract 78-91 µm high, 72-87µm wide.
Emended diagnosis: Lentin et al., 1994, p. 571
A species of Sumatradinium with hollow, acuminate to occasionally capitate processes or spines, rarely longer than 5 µm.
Emended description:
Shape: Cyst weakly to strongly dorsoventrally compressed, ambitus subcircular, suboval, rounded pentagonal to peridinioid. Apex rounded; antapex rounded to weakly bilobate and symmetrical or asymmetrical. Epicyst and hypocyst appear to be more or less equal in size. Wall relationships: Autophragm only or rarely periphragm and endophragm that are narrowly separated, as on one of the paratypes (Drugg 1970, Fig.14). Walls thin. Wall features: Surface ornamentation comprises a usually complete to less commonly incomplete reticulum; it may be granulate locally. Processes or spines hollow, acuminate to occasionally blunt or capitate, generally uniformly distributed to marginate, and may be locally aligned to indicate paratabulation. Process length generally between 3 and 5 µm. Mode of excystment: Archeopyle usually involves the loss of a large hexa isodeltaform middorsal intercalary paraplate, presumably 2a, posteriorly extending almost to the equator of the cyst. The operculum is usually free but may be adnate anteriorly. Rarely, accessory archeopyle sutures develop between paraplates adjacent to 2a and a second intercalary paraplate may be dislodged. When two wall layers are observed, they appear fused on the operculum. Paratabulation: Generally indicated by archeopyle only and assumed to be peridinialean; occasionally the alignment of processes suggests a paracingulum and possibly other parasutures. Parasulcus not identified. Size: Original material: "tract 78-97 µ high, 72-87 µm wide" (Drugg 1970, p. 121). Present material: body length 81(90)99 µm, body width 74(86)97 µm, maximum length of processes 3-4 µm.
Lentin et al., 1994, p. 574: In our reevaluation of the type material, including examination of the holotype, we noted the following: (1) The paratype (Drugg 1970, Fig. 14; Pl. 1, fig. 2 herein) is circumcavate; (2) the same specimen appears to have an archeopyle developed through the loss of more than one paraplate; (3) all the specimens illustrated by Drugg have an ornamentation comprising a complete or incomplete reticulum; (4) the processes or spines tend to be reduced in number and possibly also in size in the middorsal and midventral areas; and (5) the processes or spines are aligned, indicating a penitabulate or possibly sutural arrangement, in some areas. Together, the above observations form the basis for the emendation of this species.
Affinities:
Lentin et al., 1994, p.574: The genus Sumatradinium includes four species: S. hispidum (Drugg, 1970) Lentin and Williams, 1976 (the type), S. druggii sp.nov., S. pustulosum sp.nov., and S. soucouyantiae de Verteuil and Norris, 1992. The species can be readily separated by the nature of the processes.
Sumatradinium hispidum has short (up to 5 µm), closed, spine-like processes, which are acuminate distally and commonly penitabulate or possibly sutural. Sumatradinium soucouyantiae has processes 6--20 µm in length, which are usually hollow and distally acuminate to rounded or clavate, not furcate, and always closed. Sumatradinium druggii has processes of variable length and morphology, which usually have annular thickenings and closed furcate terminations. In some processes the "annular thickenings" may be septa but this is impossible to prove under the light microscope. Sumatradinium pustulosum has a low, pustulate ornamentation.
Originally Xenicodinium, subsequently (and now) Sumatradinium.
Holotype: Drugg, 1970, fig.12; Lentin et al., 1994, pl.1, fig.1
Paratypes: Drugg, 1970, figs.13-14; Lentin et al., 1994, pl.1, fig.2
Locus typicus: Rupat Island, Sumatra, Indonesia
Stratum typicum: Middle Miocene to Pliocene
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999
Sumatradinium hispidum (Drugg, 1970a) Lentin and Williams, 1976. This species has short, up to 5 µm, closed, spine-like processes, which are acuminate distally and commonly penitabulate or possibly sutural. Size: body length 81-99 µm, width 74-97 µm. Maximum length of processes 3-4 µm.
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Original description: Drugg, 1970, p. 121: Xenicodinium hispidum
Tract flattened dorso-ventrally, rounded pentagonal in outtline. Wall single layered, thin, finely granulate. Trapezoidal six sided intercalary archeopyle on the dorsal epitract. The operculum separates first on the lower edges similar to the mode of opening of Wetzeliella. The tract is ornamented by processes 3 µm to 5 µm long. These are hollow and usually pointed distally but occasionally exhibiting blunt to slightly capitate morphology. The density of process distribution is varriable with some specimens having fewer processes than the illustrated examples.
Dimensions: Tract 78-91 µm high, 72-87µm wide.
Emended diagnosis: Lentin et al., 1994, p. 571
A species of Sumatradinium with hollow, acuminate to occasionally capitate processes or spines, rarely longer than 5 µm.
Emended description:
Shape: Cyst weakly to strongly dorsoventrally compressed, ambitus subcircular, suboval, rounded pentagonal to peridinioid. Apex rounded; antapex rounded to weakly bilobate and symmetrical or asymmetrical. Epicyst and hypocyst appear to be more or less equal in size. Wall relationships: Autophragm only or rarely periphragm and endophragm that are narrowly separated, as on one of the paratypes (Drugg 1970, Fig.14). Walls thin. Wall features: Surface ornamentation comprises a usually complete to less commonly incomplete reticulum; it may be granulate locally. Processes or spines hollow, acuminate to occasionally blunt or capitate, generally uniformly distributed to marginate, and may be locally aligned to indicate paratabulation. Process length generally between 3 and 5 µm. Mode of excystment: Archeopyle usually involves the loss of a large hexa isodeltaform middorsal intercalary paraplate, presumably 2a, posteriorly extending almost to the equator of the cyst. The operculum is usually free but may be adnate anteriorly. Rarely, accessory archeopyle sutures develop between paraplates adjacent to 2a and a second intercalary paraplate may be dislodged. When two wall layers are observed, they appear fused on the operculum. Paratabulation: Generally indicated by archeopyle only and assumed to be peridinialean; occasionally the alignment of processes suggests a paracingulum and possibly other parasutures. Parasulcus not identified. Size: Original material: "tract 78-97 µ high, 72-87 µm wide" (Drugg 1970, p. 121). Present material: body length 81(90)99 µm, body width 74(86)97 µm, maximum length of processes 3-4 µm.
Lentin et al., 1994, p. 574: In our reevaluation of the type material, including examination of the holotype, we noted the following: (1) The paratype (Drugg 1970, Fig. 14; Pl. 1, fig. 2 herein) is circumcavate; (2) the same specimen appears to have an archeopyle developed through the loss of more than one paraplate; (3) all the specimens illustrated by Drugg have an ornamentation comprising a complete or incomplete reticulum; (4) the processes or spines tend to be reduced in number and possibly also in size in the middorsal and midventral areas; and (5) the processes or spines are aligned, indicating a penitabulate or possibly sutural arrangement, in some areas. Together, the above observations form the basis for the emendation of this species.
Affinities:
Lentin et al., 1994, p.574: The genus Sumatradinium includes four species: S. hispidum (Drugg, 1970) Lentin and Williams, 1976 (the type), S. druggii sp.nov., S. pustulosum sp.nov., and S. soucouyantiae de Verteuil and Norris, 1992. The species can be readily separated by the nature of the processes.
Sumatradinium hispidum has short (up to 5 µm), closed, spine-like processes, which are acuminate distally and commonly penitabulate or possibly sutural. Sumatradinium soucouyantiae has processes 6--20 µm in length, which are usually hollow and distally acuminate to rounded or clavate, not furcate, and always closed. Sumatradinium druggii has processes of variable length and morphology, which usually have annular thickenings and closed furcate terminations. In some processes the "annular thickenings" may be septa but this is impossible to prove under the light microscope. Sumatradinium pustulosum has a low, pustulate ornamentation.