radiolaria - rads_cenozoic - Larcopyle buetschlii radiolaria - rads_cenozoic - Larcopyle buetschlii

Larcopyle buetschlii


Classification: rads_cenozoic -> Pyloniidae -> Larcopyle -> Larcopyle buetschlii
Sister taxa: L. augusti, L. buetschlii, L. eccentricanoides, L. eccentricum, L. frakesi, L. hayesi, L. labyrinthusa, L. molle, L. nebulum, L. peregrinator, L. polyacantha, L. pulchella, L. pylomaticus, L. titan, L. weddellium, L. sp.
Sub-taxa & variants (time control age-window is: 0-800Ma)
Larcopyle buetschli chenmuhongi

neptune records:
Larcopyle buetschlii orion

neptune records:

Taxonomy

Citation: Larcopyle buetschlii Dreyer 1889

taxonomic rank: species
Basionym: Larcopyle buetschlii
Synonyms:
1889 Larcopyle bütschlii - Dreyer p. 124-125; pl. 10, fig. 70
1966 Larcopyle bütschlii - Benson p. 280-282; pl. 19, figs. 3,5, (not 4)
1966 Larcopyle? sp. - Benson p. 279-280; pl. 19, figs 1-2
1977 Larcopyle butschlii (?) - Kling p. 217; pl. 1, fig. 11
1977 Larcopyle butschlii - Molina-Cruz p. 335; pl. 3, figs. 10-11
1979 Larcopyle butschlii - Nigrini and Moore p. S131-S132; pl. 17, figs 1a-1b
1983 Larcopyle butschlii group - Benson p. 504-505
1984 Larcopyle buetschlii Nigrini and Lombari, pl. 13, figs. 1a, b
1998 Larcopyle butschlii - Boltovskoy figs. 5B, 15.85
2005 Larcopyle buetschlii Lazarus et al. 2005, p. 102-3
2017 Larcopyle buetschlii Zhang and Suzuki 2017, p. 30-36, figs. 19-21
Taxonomic discussion:

Description. Test is ellipsoid in shape with a bore pylome and consists of a pylodiscid-type central combination, two or three pseudo-concentric shells, and outermost coverage shell with fine pores. The Lt-axis of the central combination is oblique or parallel to the longest axis (the Ug-axis) of the test. One or two spiral girdles develop from one side of the central combination and gradually rotate around the inner skeleton. The axes of the spiral girdles continuously rotate in three dimensions in Type 1 coordinates, but this rotation tends to be parallel to the previously developed girdle just below that girdle. Consequently, they seem to develop two or three pseudo-concentric shells from one view in Type 2 coordinates, whereas they resemble spirals from the other view in the same coordinates. The outer girdle is connected to the inner girdle with vertical pillar beams. Numerous pillar beams are present, but they rarely pierce through an outer girdle. Pores of these spiral gir- dles are large and polygonal to elliptical in shape. The pore sizes of these spiral girdles are largely related on the density of the pillar beams. The outermost coverage shell is ellipsoid in shape with numerous small pores that form a thick wall. The ratio of the short and long diameters of the outermost shell is ca. 0.6–0.7. No by-spines or radial spines are present on the surface of the outermost coverage shell. A bore pylome tends to develop on one side of the outermost coverage shell and is associated with a number of spinules. This pylome is closed in some fully mature forms, and no distinctive structure corresponding to a pylome has been detected inside the test. The outermost coverage shell is also connected with the internal spiral structures of numerous pillar beams.

Remarks. The Larcopyle buetschlii group has been used in several studies for a wide variety of Larcopyle species with spiral internal structures and ellipsoid appearances. The “L. buetschlii” specimens from the Sea of Japan generally have more tightly coiled inner structures, more robust outermost coverage shell, and radial spines or by- spines across the outermost coverage shell (e.g., Itaki, 2009). These observations strongly suggest that the Larcopyle buetschlii from the Sea of Japan is morphologically independent from our Indian Larcopyle buetschlii. We examined the topotypic specimens from the H.M.S. Challenger Stations 261, 266, and 271 and found equivalent specimens to the type image in Dreyer (1889) in the Station 271 sample (Figure 17.7-12). We confirmed the same morphological characteristics between specimens from Station 271 and illustrated specimens of Larcopyle buetschlii buetschlii from the Indian Ocean. Larcopyle buetschlii buetschlii is different from Larcopyle buetschlii n. subsp. based on the former’s major spiral girdles, the smoother surface of these spiral girdles, and the final thick coverage of fine pores if present. Lazarus et al. (2005) synonymized Larnacantha polyacantha Campbell and Clark, 1944, with L. buetschlii, but we separate the former from the synonym of the latter because the spiral patterns of each differ. The subspecific name “buetschlii” applies strictly to specimens that match the above definition. This subspecies is limited to warm, open regions of the Pacific, whereas the morphotype described by Itaki (2009, 2016) is limited to the Sea of Japan and, rarely, the Sea of Okhotsk and the boreal North Pacific. [from Zhang and Suzuki 2017]

NOTE added by mikrotax editor (dbl): Zhang and Suzuki's claim that Lazarus et al. synonymized L. polyacantha with L. buetschlii is incorrect, and apparently due their to misreading a centered new taxon entry title in Lazarus et al as a left justified synonym entry.

Catalog entries: Larcopyle buetschlii


Translated description:

The complete outline of the lens-shaped, flattened shell is oval, in which, although not very significantly, the oral pole is wider than the aboral. In the centre of the skeleton there is clearly visible a ‘trigonale’, Larnacilla shaped medullary shell, while the shell is enclosed externally by a unified shell mantle. This has a smooth surface and small irregular polygona to round meshes of unequal sizes which are ap- proximately twice the breadth of the beams, sometimes also wider. Between the Larnacilla shaped medullary shell and the outer shell mantle there is a construction of opaline beams, whose form indicates a close affinity to the lithelids and phorticids (for details see illustration). The beams of this inner construction are thicker than those of the shell mantle. The pylome is relatively small, about as broad as the medul- lary shell, and is framed by small teeth. The opaline beams of this form are thin and give the entire shell a very soft, transparent impression, and thus the finer structure and layout of the opaline beams is rather difficult to recognize.

 

As these pylome bearing larcoids cannot with certainty be assigned to described larcoid families, I have created a new family for them, which to the previous nine families can be added as the tenth. All not yet discovered pylome bearing larcoids would most simply best be assigned to this family, regardless if they have other shell features that connect them to one of the known nine families.

Fig. 70. Larcopyle Bütschli, nov. spec., nov. gen. 435X enlargement.

In order to clearly illustrate this very complicated form, almost all of the upper (except for a small piece to the right of the pylome), and the middle part of the lower, outer fine-meshed shell mantle has been shown broken away. Similarly, part of the upper, inner coarse spiral beam structure has been removed, to show the central larnacilla shaped medullary shell. [translation from Lazarus et al. 2005]

Description


Published descriptions


Benson 1966 - Larcopyle butschlii

Large ellipsoidal shell when fully developed with regular outline; surface with scattered short (5-25 µm) conical spines or thorns continuous inward as beams; pores unequal, irregular, larger than those of preceding species [Larcopyle? sp]; at one pole in a few specimens a cluster of short (5-12 µm) conical spines but without definite opening or pylome. Internal structure consists of irregular but generally recognizable latticed lamellae joined by numerous radial beams, in several specimens with an identifiable pylonid structure of concentric trizonal shells or spirals, particularly apparent in those with outer shell not fully developed (Pl. 19, figs. 3-4).Those specimens with a recognizable internal triangular pylodiscid shell were placed within Discopyle ? sp.

Measurements: based on 30 specimens from stations 71, 81, 136, and 184: major diameter of test 135-246 µm, minor diameter 81-172 µm; length of axes of internal trizonal shells (8 specimens): P1 18-33 µm, P2 59- 95 µm, T1 14-18 µm, T2 39-74 µm.

Remarks: This species is identified as Larcopyle bütschlii on the basis of the internal pylonid structure and the presence of the cluster of spines at one pole. Dreyer's illustration (1889, Pl. 10, fig. 70) differs from the Gulf forms in the smooth ellipsoidal shell with more regular pores. In this respect it is more like Discopyle? sp. from the Gulf, but Dreyer (1889, p. 124) states that the internal structure is composed of trizonal shells, not pylodiscid shells. It may be that Discopyle ? sp. and this species are the same, but due to problems of orientation the pylodiscid shell is difficult to recognize.

Distribution: Specimens identifiable as this species are generally rare but cosmopolitan in the Gulf, being absent at stations 192, 203, 208, and 214 and common at stations 106 and 206.At station 206 the total population is only 201; therefore, results obtained from this station are not significantly comparable to those of other stations.A significantly higher frequency (2.8%) was noted at station 106 which is located within the diatomite basin facies; therefore, this species may be controlled in part by upwelling. It is almost common at stations 91, 92, and 93, located within and between areas of upwelling along both coasts. Throughout the remainder of the Gulf this group does not undergo any significant changes in its frequency. Because identification of these forms is difficult, interpretations regarding their distribution cannot be easily made. It is cosmopolitan in the Gulf, and its distribution in local areas may be favored by upwelling. Larcopyle bütschlii was described by Dreyer (1889, p. 125) from Challenger stations 232, 266, and 271.The first is located off the east coast of Japan in the Kuroshio Current, the other two in the central equatorial Pacific. This species, therefore, is at least tropical to temperate, but it has not been reported from polar latitudes. \ From: Benson, 1966, p. 280-282; pl. 19, figs. 3,5, (not 4):Larcopyle btschlii Dreyer Larcopyle bütschlii Dreyer, 1889, Jenaische Zeitschr. Naturwiss., vol. 23, pp. 124-125, Pl. 10, fig. 70.


Benson 1966 - Larcopyle butschlii

Test a relatively small, elongate ellipsoid, with a smooth surface and at one pole a cluster of short (4-21 µm) thorns or spines but without a definite opening except for the pores of the latticed shell. Surface of test smooth but slightly irregular; pores irregular, of unequal size, many representing secondary pores filling the spaces of larger pores. Internal structure appears as a loose, spongy network; in a few specimens internal shadows appear to have some kind of arrangement, either spiral or concentric, but if a trizonal structure does exist, it is irregular.

Measurements: based on 30 specimens from stations 71, 81, arid 136: major diameter of test 82-151 µm, minor diameter 60-105 µm.

Remarks: This species is distinguished from Larcopyle bütschlii by its relatively small size, its smooth surface without radial spines, and the presence of secondary pores filling the spaces of the larger pores of the outer shell. Although without a definite pylome, the cluster of spines at one pole resembles one and is similar to the apparent pylome of Larcopyle bütschlii Dreyer (1889, Pl. 10, fig. 70).For these reasons it is placed within the genus Larcopyle Dreyer (1889, p. 124).Because the internal structure of this species is not definitely known, it was not given a new species name.

Distribution: This species is cosmopolitan in the Gulf, being absent only at stations 90, 203, 206, and 214.It is rare at all stations except 64, 71, 81, 99, and 133 where it is common. Its highest (4.0%) and second highest (3.0%) frequencies were observed at stations 64 and 99, respectively, both located in known areas of upwelling off the coast of the Mexican mainland. Station 133 is located in the diatomite facies in a known area of upwelling off the Baja California coast. Stations 71 and 81 are located near areas of upwelling off both coasts. The frequency of this species does not increase in other areas of upwelling, although at station 192 it is almost common. The distribution of this cosmopolitan species in the Gulf, therefore, is controlled locally by upwelling. \ From: Benson, 1966, p. 279-280; pl. 19, figs 1-2:Larcopyle? sp.


Benson 1983 - Larcopyle butschlii

Benson, 1983, p. 504-505:Larcopyle butschlii Dreyer group

Remarks: This group of ellipsoidal tests with regular outline is identified on the basis of its internal pylonid structure and the presence of a cluster of spines at one pole of the test.


Biogeography and Palaeobiology

Biostratigraphic distribution

Geological Range:
Last occurrence (top): Extant. Data source: Lazarus et al. 2015 - "R age group"
First occurrence (base): within Quaternary Period (0.00-2.59Ma, base in Gelasian stage). Data source: Lazarus et al. 2015 - "R age group"

Plot of occurrence data:

References:

Benson, R. N. (1966). Recent Radiolaria from the Gulf of California. Thesis, Minnesota University. 1-577. gs

Benson, R. N. (1983). Quaternary radiolarians from the Mouth of the Gulf of California, Deep Sea Drilling Project Leg 65. Initial Reports of the Deep Sea Drilling Project. 65: 491-523. gs

Boltovskoy, D. (1998). Classification and distribution of south Atlantic recent polycystine Radiolaria. Palaeontologia Electronica. -. gs

Dreyer, F (1889). Die Pylombildungen in vergleichend-anatomischer und entwicklugs-geschichtlicher Beziehung bei Radiolarien und bei Protisten uberhaupt, nebst System und Beschreibung neuer und der bis jetzt bekannten pylomatischen Spummellarien. Jenaische Zeitschrift für Naturwissenschaft. 23: 77-214. gs O

Kling, S. A. (1977). Local and regional imprints on radiolarian assemblages from California coastal basin sediments. Marine Micropaleontology. 2(2): 207-221. gs

Lazarus, D., Faust, K. & Popova-Goll, I. (2005). New species of prunoid radiolarians from the Antarctic Neogene. Journal of Micropalaeontology. 24(2): 97-121. gs

Molina-Cruz, A. (1977). Radiolarian assemblages and their relationship to the oceanography of the subtropical southeastern Pacific. Marine Micropaleontology. 2(4): 315-352. gs

Nigrini, C. A. & Lombari, G. (1984). A guide to Miocene Radiolaria. Cushman Foundation for Foraminiferal Research, Special Publication. 22: 1-206. gs O

Nigrini, C. A. & Moore, T. C. Jr. (1979). A guide to modern Radiolaria. Cushman Foundation for Foraminiferal Research, Special Publication. 16: 1-260. gs O

Zhang, L. & Suzuki, N. (2017). Taxonomy and species diversity of Holocene pylonioid radiolarians from surface sediments of the northeastern Indian Ocean. Palaeontologia Electronica. 20(3): -. gs


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Larcopyle buetschlii compiled by the radiolaria@mikrotax project team viewed: 21-5-2024

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