Glomospira charoides (Jones & Parker, 1860)



Fig. 22. Subjective synonyms of Glomospira charoides (Jones & Parker). All drawings are of holotypes or type figures. 1 - Earliest figure of G. charoides, from Carpenter et al. (1862). 2 - type specimens of G. subarctica, redrawn after Chamney (1969), 3 - type figure of G. praecharoides, redrawn after Soliman (1972), 4 - type figures of G. charoides corona, after Cushman & Jarvis (1928), 5 - holotype of G. charoides antarctica, from Saidova (1975), 6 - holotype of G. favilla, redrawn after Emiliani (1954), 7 - type specimens of G. pileolus, from Subbotina (1960), 8 - holotype of G. charoides leroyi, from Said & Kenawy (1956), 9 - holotype of G. charoides profunda, redrawn after Saidova (1975), 10 - holotype of G. saturniformis, from Majzon (1943), 11 - type specimens of G. subarctica saturna, redrawn after Chamney (1969), 12 - type specimen of G. charoides extendens, after Emiliani (1954).


ORIGINAL DESIGNATION: Trochammina squamata var. charoides Jones & Parker, 1860.

TYPE REFERENCE: Jones, T.R. & Parker, W.K. 1860. On the Rhizopodal fauna of the Mediterranean compared with that of the Italian and some other Tertiary deposits. Quarterly Journal of the Geological Society of London, 16, 292-307 [no type figure given].
See also: Carpenter et al. 1862. Ray Society, London, pl. 11, fig. 4 [earliest figure]; Berggren, W. A. & Kaminski, M. A., 1990, NATO ASI Series C327, pl. 1, fig. 2 (lectotype).

TYPE SPECIMEN: Deposited in the micropaleontological collections of the British Museum (Natural History). Four slides containing syntypes forming part of the Parker Collection, were purchased by the British Museum in 1892 and were subsequently catalogued by T.R. Jones. These slides are registered as follows:
Slide 1894.4.3.540: off Gozo Island (Malta), 704 fathoms.
Slide 1894.4.3.585: between Malta and the Grecian Archipelago.
Slide 1894.4.3.616: Near Ipsara, 500 fathoms.
Slide 1894.4.3.624: NW of Crete, 250 fathoms. The lectotype, designated by Berggren & Kaminski (1990; pl. 1, fig. 2), is the specimen illustrated by Carpenter, et al. (reproduced in fig. 18-1). We found this specimen in Slide 1894.4.3.540. It has been assigned the separate catalog number ZF 4875.

TYPE LEVEL: Recent.

TYPE LOCALITY: Not originally designated. Jones & Parker (1860) listed several stations in the Greek archepelago and off Crete. The lectotype specimen is from a dredge sample collected on Oct. 3, 1859 aboard the HMS Firebrand, from a depth of 704 fathoms 33 mi SE of Cape Demitri, Gozo Island, Malta (36° 18'N, 13° 33'E).

DIAGNOSTIC FEATURES: Test free, proloculus followed by a trochospirally enrolled, undivided tubular second chamber, coiled about a vertical axis. The test is comprised of about three layers of coils, and there are typically six or seven whorls in the outermost layer. The last whorl may deviate from the axis of coiling, and be inclined to the axis, loop-shaped, or irregular. Wall finely agglutinated, cemented with undifferentiated organic mater, with inner and outer organic linings, and a smooth surface. Aperture at the open end of the tube.

SIZE: Diameter ranges up to .40 mm. The lectotype specimen is .27 mm in diameter.

SYNONYMS:
Glomospira charoides (Jones & Parker) var. corona Cushman & Jarvis. Cushman, J.A. & Jarvis, P.W. 1928, Contr. Cushman Lab. Foram. Res., 4:89, pl. 12, figs. 9-11 [Paleocene, Trinidad].
Glomospira saturniformis Majzon. Majzon, L. 1943, Magyar K. Foldt. Int. Evk., Budapest 37: 31, pl. 5, fig. 9 [Late Cretaceous, Carpathians].
Glomospira charoides (Jones & Parker) var. extendens Emiliani. Emiliani, C. 1954, Paleontogr. Italica 48: 133, pl. 13, fig. 14a-c [Oligocene, Appennines].
Glomospira favilla Emiliani. Emiliani, C. 1954, Paleontogr. Italica B>48:133, pl. 13, fig. 15a-c [Oligocene, Apennines].
Glomospira charoides (Jones & Parker) var. leroyi Said & Kenawy. Said, R. & Kenawy, A. 1956, Micropal. 2:120, pl. 1, fig. 6 [Paleocene, Egypt].
Glomospira subcharoides Khalilov. Khalilov, D.M. 1959. Izvest. Akad. Nauk. Azerbaidzhan. SSR, Ser. geol.-geogr. nauk, 6, p. 25, pl. 1, fig. 1a-c. [Valanginian, Azerbaidzan].
Glomospira subcharoides var. sphaera Khalilov. Khalilov, D.M. 1959. Izvest. Akad. Nauk. Azerbaidzhan. SSR, Ser. geol.-geogr. nauk, 6, p. 27, pl. 1, fig. 1d. [Hauterivian, Azerbaidzan].
Glomospira charoides (Parker & Jones) var. minima Subbotina. Subbotina, N.N. 1960, Trudy VNIGRI 153 , p. 179, pl. 1, figs. 11a-12b [Early Miocene, Ukraine].
Glomospira pileolus Subbotina. Subbotina, N.N. 1960, Trudy VNIGRI 153, p. 179, pl. 1, figs. 13a-14c [Early Miocene, Ukraine].
Glomospira iranensis Kavary. Kavary A. & Frizzel, D. 1963, Missouri Univ. School of Mines & Metal. Bull. 102:10, pl. 1, figs. 2-7 [Paleocene, Iran].
Glomospira subarctica Chamney. Chamney, T.P. 1969, GSC Bull 185, p. 16, pl. 2, figs. 7-9 [Barremian, Mackenzie District, N.W.T.].
Glomospira subarctica saturna Chamney. Chamney, T.P. 1969, GSC Bull 185, p. 17, pl. 2, figs. 10-12. [Barremian, Mackenzie District, N.W.T.].
Glomospira praecharoides Soliman. Soliman, H.A. 1972. Revue de Micropal. 15, p. 36, pl. 1, figs. 1, 2; pl. 2, fig. 1 [Cenomanian, Carpathians].
Usbekistania charoides antarctica Saidova. Saidova, Kh. 1975, p. 71, pl. 96, fig. 3 [Recent, Pacific].
Usbekistania charoides profunda Saidova. Saidova, Kh. 1975, p. 71, pl. 18, fig. 5 [Recent, Pacific].
Glomospira fulgida Maslun. Maslun, N.V. 1987, Paleont. Sbornik, 24, p. 69, pl. 2, fig. 3 [Eocene, Carpathians].

OBSERVED OCCURRENCES: Glomospira charoides is a cosmopolitan species in the modern ocean, and is present in Cretaceous to Paleogene slope, flysch-type, and abyssal assemblages. It is the dominant species of Glomospira in Cretaceous and Paleogene abyssal assemblages. However, we did not find G. charoides in our box core and gravity core samples collected on the Hatteras and Nares Abyssal Plains (Glomospira gordialis is the only species of Glomospira present in these samples). Glomospira charoides occurs in low numbers along the Nova Scotian Continental Slope and Rise between 2225 and 4815 m (Schröder, 1986).
Although G. charoides is present in most deep-sea environments and is long-ranging stratigraphically, variations in the abundance of this species can be useful for paleoecology and biostratigraphy. In the modern Mediterranean, the species displays the highest relative abundance in oligotrophic areas such as the Levantine Basin (De Rijk et al., 2000). Its upper depth limit is linked to a sea-floor carbon flux value of around 2.5 gC/m2-yr, but the species only flourishes under conditions of very low carbon flux (<0.7 gC/m2-yr). It has also been found in increased numbers near the base of Pliocene - Pleistocene sapropel layers observed in piston cores from the eastern Mediterranean (Cita & Grignini, 1983). This indicates that G. charoides can also tolerate oxygen-deficient environments and organic-rich substrates. Although at first this seems to be conflicting information, geochemical data indicate that the onset of Saprapel S1 in the Aegean Sea was actually marked by a decline in net primary productivity, not an increase as suggested by some earlier authors (Aksu et al., 1999). The eastern Mediterranean sapropels appear to be linked to stable density stratification rather than increased productivy. Therefore, G. charoides appears to be responding more to the change in productivity rather than oxygen. On the other hand, in the Green Canyon area of the Gulf of Mexico, G. charoides was observed in relatively high proportions in areas of natural hydrocarbon seepage (Kaminski, 1988), and it was observed in higher abundances at "hydrothermal mud" sites in the proximity of active hydrothermal vents in the Juan de Fuca Ridge (Jonasson et al. 1995). In certain areas of the North Atlantic, as well as in the Mediterranean and Alpine flysch basins, a level late Early Eocene to early Middle Eocene in age contains increased proportions of Glomospira, in both clastic and pelagic deep sea sediments. This level is evident in faunal abundance tables published by Grün et al. (1964) from the Vienna Flysch; by Jurkiewicz (1967) from the Carpathian flysch units in southeastern Poland, and by Winkler (1984) from the Schlieren Flysch in Switzerland. In the North Atlantic ODP holes, this "Glomospira facies" is associated with siliceous microfossils and higher amounts of organic carbon indicating higher organic productivity in the surface waters. This early Eocene "Glomospira facies" is entirely comparable to the "Biofacies B" assemblages described from the Lower Campanian by Kuhnt & Kaminski (1989), and from the Lower Cretaceous by Holbourn & Kaminski (1997). At Gubbio and at Zumaya, an acme in Glomospira occurs just above the P/E benthic extinction (Ortiz, 1995; S. Galeotti, personal communication), an event which is associated with a rapid change in productivity and the dissociation of sedimentary methane hydrates. We therefore interpret higher proportions of Glomospira as reflecting unstable trophic conditions. The "Glomospira facies" serves as a useful correlation horizon between the Labrador Sea, Norwegian-Greenland Sea, and Mediterranean flysch basins. On the Labrador Shelf and Grand Banks, the average last occurrence of G. charoides (= G. corona) is near the base of Zone LGR2 (immediately above the Paleocene/Eocene boundary). In the Beaufort-Mackenzie Basin, it is only observed in high numbers in the upper Miocene Akpak Sequence, which is interpreted as deep-water (deposited in a lower continental slope to continental rise setting).
Pflum & Frerichs (1976) reported that G. charoides has a depressed upper depth limit near the mouth of the Mississippi River. In this respect, G. charoides is a species which is environmentally sensitive and adversely affected by river discharge or "deltaic influence".

KNOWN STRATIGRAPHIC RANGE: Jurassic to Recent.

BATHYMETRY: Bathyal to abyssal in Cretaceous to Paleogene assemblages. May be restricted to the Continental Slope and Rise in the modern Atlantic. In the Gulf of Gascony (eastern Atlantic), Pujos-Lamy (1973) reported its upper depth limit at 1,975 m, coincident with that of Melonis pompilioides. In the Gulf of Mexico it occurs at shallower depths; Pflum & Frerichs (1976) reported its upper depth limit at around 100 m. There are reports of G. charoides on the continental shelf at high latitudes. Balkwill & Wright (1885) illustrated a specimen from 24 fathoms off Kish Bank, Ireland.

REMARKS: Glomospira charoides was designated the type species of the genus Repmanina by Suleymanov (in Arapova & Suleymanov, 1966), and this genus was considered valid by Loeblich & Tappan (1988). Loeblich & Tappan defined Repmanina as follows:

"Test free, proloculus followed by elongate tubular undivided second chamber that is trochospirally coiled about a straight axis; wall finely agglutinated; aperture at the open end of the tubular chamber."

The mode of coiling described by Suleymanov has been confirmed by cross-sections of G. charoides and G. gordialis published by Bender (1995; pl. 3; fig. 1), which shows that a typical specimen possesses three layers of trochospirally enrolled chambers. The proloculus is surrounded by four volutions of the chamber; in the final volution, six coils are present. These sections demonstrate that both species are congeneric [see remarks under Glomospira gordialis].



Fig. 22-2. Lateral cross section of G. charoides, showing the volutions of the chamber and mode of coiling. Redrawn from Bender (1995)


Numerous junior synonyms or subspecies of Glomospira charoides have been described in the literature (Figure 22-1), and some of these morphotypes may be assigned to different genera according to Loeblich & Tappan (1987). In some individuals, the tubular chamber may abruptly change coiling direction or become irregular near the end of the tube. Cushman (1918) noted in his description of G. charoides that the tubular chamber turns "at right angles to the preceeding axis and makes a partial or even complete revolution about the earlier formed globular test". Nevertheless, subsequent authors have described specimens which display this feature as different species. The Paleocene species Usbekistania mubarekensis Suleymanov is the equivalent of a G. charoides with two or more planispiral whorls oriented in the plane of the vertical axis. We have observed rare specimens of G. charoides with the last whorl oriented 90° to the previous set of whorls in the Eocene of the Atlantic and in the Cretaceous of the Indian Ocean, but in each case there is less than one whorl. Therefore, Usbekistania mubarekensis may be a geographically restricted decendant of G. charoides, and is probably taxonomically distinct. The following is a list of varieties and subspecies of G. charoides that have been described in the literature:
  • Usbekistania charoides antarctica Saidova, 1975 - reportedly differs from G. charoides in possessing a very smooth and lusterous surface.
  • Glomospira charoides corona Cushman & Jarvis, 1928 - A specimen of G. charoides with an incomplete outer layer of whorls. There are only one or two revolutions in the outermost layer of whorls, which gives the specimen the appearance of having a crown.
  • Glomospira charoides extendens Emiliani 1954 - the last whorl encircles the test at 90° to the plane of coiling of the previous layer of whorls. However, if it encircles the test completely it remains trochospiral, and therefore differs from "Usbekistania" which has planispiral whorls.
  • Glomospira charoides leroyi Said & Kenawy, 1956 - The last whorl instead of spiraling downward in the normal manner, crosses over itself and spirals upward, forming a concave "crown". This specimen is housed in the USNM in slide USNM 73943.
  • Glomospira subcharoides Khalilov, 1959 - this Valanginian form was described as being biconvex, with a "keel". The type figure appears to be nothing more than a crushed specimen of G. charoides.
  • Glomospira subcharoides var. sphaera Khalilov, 1959 - described by Khalilov as differing from Glomospira subcharoides by its subsphaerical shape, and younger (Hauterivian) stratigraphical occurrence.
  • Glomospira charoides minima Subbotina, 1960 - this form was reported from the Lower Miocene of the Carpathian foreland in the Ukraine. Subbotina reported that the "test differs from the typical form in its smaller dimensions, and in sometimes possessing a test that is elongated in the axis of coiling, and in sometimes broadening towards the aperture". The dimensions were reported as 0.05 x 0.09 mm.
  • Usbekistania charoides profunda Saidova, 1975 - A deep abyssal variety which reportedly differs from G. charoides in its small size (200 - 250 microns).
  • Glomospira favilla Emiliani, 1954 - A specimen of G. charoides with an incomplete outer layer of whorls. There are about four revolutions in its outermost layer. This is exactly the same as Glomospira pileolus Subbotina, 1960.
  • Glomospira improcera Harris & Jobe, 1951 - The last few whorls encircle the middle of the test in the plane of coiling and are somewhat larger than preceeding whorls.
  • Glomospira pileolus Subbotina, 1960 - This species was also described from the Lower Miocene of the Carpathian foreland in the Ukraine. Subbotina described it as "cup-shaped". This morphotype is identical to G. favilla.
  • Glomospira iranensis Kavary, in Kavary & Frizzel, 1963 - Kavary made the observation that tubular chamber coils "upward and reversibly downward while maintaining the same axis". He separated G. iranensis on this basis, and was thereby arguably the first author who resolved the coiling mode of G. charoides.
  • Glomospira praecharoides Soliman, 1972 - A species from the Cenomanian of the Carpathians which reportedly differs from the Recent G. charoides in having a greater total number of whorls, and in having more whorls in one layer.
  • Glomospira praegordialis Soliman, 1972 - Soliman's illustration of a specimen in cross section shows that the specimen is coiled initially as in G. charoides, not as in G. gordialis. The final whorls are coiled glomospirally, but this may be an aberrent specimen.
  • Glomospira saturniformis Majzon, 1943 - The last whorl encircles the test in a slightly meandering whorl, oriented about 60° to the plane of the last layer of whorls. Very similar to G. charoides extendens.
  • Glomospira subarctica Chamney, 1969 - an Early Cretaceous form which reportedly differs in possessing a slightly irregular coiling and in having an oblate spheroidal shape. (May be crushed).
  • Glomospira subarctica saturna Chamney, 1969 - possesses a final planispiral whorl that encircles the test.
  • Glomospira fulgida Maslun, 1987 - A laterally compressed Late Eocene form with a larger diameter final whorl, 160 - 190 microns in maximum diameter.


Other unnamed varients of the coiling plan also occur in fossil assemblages alongside "normal" specimens of Glomospira charoides. These varients include the following:

  1. Pl. 18 fig. 11 - a specimen in which the tubular chamber reverses direction 180°, doubles back, and coils in the opposite direction.
  2. Pl. 18 figs. 4, 13 - the final layer of whorls is inclined at a 30 to 45° angle to the previous layer of whorls.
  3. Pl. 18 fig. 9 - the final portion of the tube makes a loop around the dorsal surface of the test.
  4. Pl. 18 figs. 5, 10 - After building a "charoides" - shaped test, the tubular chamber coils irregularly, as in G. irregularis.
  5. The diameter of the tubular chamber increases somewhat faster than usual, resulting in a relatively large sized test in which the early portion of the test is quickly enveloped by the last layer of whorls. These specimens are common in the Lizard Springs Formation of Trinidad.


Of the above list of species and varieties, we regard G. charoides antarctica, G. charoides profunda, G. iranensis, G. praecharoides, and G. subarctica to be fully synonymous outright. The other named and unnamed forms are various ontogenic or geriatric growth stages which occur naturally in any large population. For example, in a single sample from the Eocene of the Polish Carpathians, we found specimens corresponding to the "charoides","corona", "favilla", "extendens" or "saturniformis" and unnamed morphotypes 2, 3, and 4. Specimens from this sample are illustrated in pl. 22, figs. 2-7. Another suite of specimens from the Lower Cretaceous of the Indian Ocean is shown in pl. 22, figs. 13-16.
In our opinion, the different named and unnamed varients simply reflect the ontogeny and the inherent genetic variability of Glomospira charoides and should not be assigned subspecies status. While we agree with the statement by Chamney (1969) that Early Cretaceous specimens coil somewhat more irregularly than modern populations, we do not regard the frequency of aberrant forms to be a valid taxonomic criterion. Genetic variability within a species is known to vary from population to population and through time. The observation that in some Cretaceous populations rare individuals coil irregularly in later stages of ontogeny may suggest some genetic exchange with Glomospira irregularis (?hybrids). Alternatively, since irregular glomospirids are known from as far back as the Paleozoic, it suggests retention of ancestral traits.

ILLUSTRATIONS: Plate 22 - Glomospira charoides (Jones & Parker)
Fig. 1. Recent, Gozo Island 704 fathoms, Lectotype, Parker Collection, BMNH no. ZF 4875, ex Slide 1894.4.3.540; Fig. 2-7. Early Eocene, Szklary Poland, Skole Unit of the Polish Carpthians. All specimens from a single sample. fig. 2 - G. charoides charoides morphotype; fig. 3 - "Glomospira favilla" or "Glomospira pileolus" morphotype; fig. 4 - "Glomospira charoides corona" morphotype; fig. 5 - unnamed morphotype #2, with inclined last whorl; fig. 6 - "Glomospira charoides extendens" morphotype; fig. 7 - unnamed morphotype # 4, with irregular tube end; Fig. 8. Early Eocene, ODP Site 647, Labrador Sea, "Glomospira charoides extendens" morphotype; Fig. 9-12. Late Cretaceous, DSDP Site 137, Eastern Atlantic Abyssal Plain. fig. 9 - the equivalent of "Glomospira praecharoides"; fig. 10 - unnamed morphotype # 3, with a looped last whorl; fig. 11 - unnamed morphotype # 4, with irregular tube; fig. 12 - unnamed morphotype # 1, with a tube that doubles back 180°; Fig.13-16. Early Cretaceous, ODP Site 765, Argo Abyssal Plain. fig. 13 - the equivalent of "Glomospira subarctica"; fig. 14 - "Glomospira subarctica" with inclined last layer of whorls; fig. 15 - "Glomospira subarctica" with inclined last layer of whorls; fig. 16 - the equivalent of "Glomospira subarctica saturna" or "Glomospira saturniformis".