Marine Micropaleontology 86–87 (2012) 1–10

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Marine Micropaleontology

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Biogeography and ecostratigraphy of Late Quaternary planktonic foraminiferaltaphocoenoses in the Leeward Islands, Lesser Antilles, NE Caribbean Sea

Brent WilsonPetroleum Geoscience Programme, Department of Chemical Engineering, The University of the West Indies, St. Augustine, Trinidad and Tobago

E-mail address: brent.wilson@sta.uwi.edu.

0377-8398/$ – see front matter © 2012 Elsevier B.V. Alldoi:10.1016/j.marmicro.2011.12.002

a b s t r a c t

a r t i c l e i n f o

Article history:Received 3 March 2011Received in revised form 23 December 2011Accepted 30 December 2011

Keywords:foraminiferabiogeographyecostratigraphySHE analysisalpha diversitybeta diversitycomplementarityAnegada PassageOrinoco Plume

The Leeward Islands lie within an oceanographically complex area influenced by North Atlantic Gyre flow andtheOrinoco plume. LateQuaternary planktonic foraminiferal assemblages are reported from threemiddle bathy-al piston cores (from NW to SE: En20-2, En20-10, En20-16) in the Leeward Islands. En20-2 was obtained closestto the 200 m bathymetric contour, En20-10 farthest offshore. The bathyal benthonic foraminifera from En20-2are indicative of high surface productivity. The planktonic foraminiferal assemblages differ between the cores.The “Globigerinoides ruber group” (=white and pink G. ruber+G. cyclostomus) typically increases shoreward,but in this study it was most abundant in En20-10. West of the study area (i.e., around Puerto Rico), white-walled specimens form ~66% of the “G. ruber group”, but in the Leeward Islands the percentages are higher(mean 81.7% of total “G. ruber group”). Globigerinita glutinata and Globoturborotalia rubescens (pink) were attheir most abundant in the SE core En20-16, while G. rubescens (white) was at its most abundant in the NWcore En20-2. Comparison with benthonic foraminiferal distributions suggests that the following planktonic spe-cies have potential as indicators of surface productivity, Globigerinella aequilateralis, G. glutinata and Globorotaliainflata being indicative of enhanced surface productivity and Globigerinoides immaturus, G. trilobus var. and Glo-borotalia tumida of low surface productivity. Bottom-up SHEAnalysis for Biozone Identification (SHEBI) indicatesthat each core contains several abundance biozones (ABs), but these do not correlate between the cores. Alphadiversities were SE=8.3–14.3 effective species, while beta diversities ranged from 0.65 to 1.54, but only twowere statistically significant. Complementarities (64.7–87.6%) indicate that the AB boundaries reflect changesin the relative abundances of species, not overall diversity.

© 2012 Elsevier B.V. All rights reserved.

1. Introduction

Species of the Order Foraminiferida Eichwald are either planktonicor benthonic, either floating within the surface waters or living at theseafloor, respectively. As evidenced by such books as those byHemleben et al. (1990) and Murray (2006), or the topics of chaptersin Sen Gupta (1999), foraminiferal workers tend to study eitherplanktonic or benthonic foraminifera. Studies comparing the distribu-tions of the two groups are rare.

The ecologies of planktonic and benthonic foraminifera are notcompletely independent, however. The planktonic foraminifera con-sume other plankton for food (although some species augment theirfood supply by harbouring photosynthetic symbionts harvestedfrom the plankton) and community composition varies with surfaceproductivity (Siccha et al., 2009). Meanwhile, benthonic foraminiferaliving below the photic zone are dependent for nutrition on the rainof detritus (mostly dead plankton) derived from the water column(Gooday, 1994, 2002; Smart and Gooday, 2006). Schnitker (1994)showed that the benthonic foraminiferal faunal composition in

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areas of high surface productivity is correlated with the productivityof the overlying surface waters (see also Phleger and Soutar, 1973).This suggests that benthonic and planktonic foraminiferal biogeogra-phies might reflect one another.

Wilson and Wilson (2011) found that the same species of near-shore (b3 m water depth) benthonic foraminifera occur throughoutthe eastern Caribbean Sea (Fig. 1). The biogeography of the deeperwater benthonic foraminifera in the region is, however, more complex.Galluzzo et al. (1990) documented two assemblages in deeper waterwithin the Grenada Basin: (a) a low-oxygen, high-nutrient fauna ofBulimina aculeata, B. alazanensis, Uvigerina auberiana at 1000–2100 mand (b) an assemblage in central basin areas >2400 m dominated byCibicides wuellerstorfi. However, they found Q-mode cluster analysisseparated assemblage (b) into NE and SW sub-assemblages. This sug-gests a situation more complex than simple depth-stratification andmay reflect the influence of Orinoco River inflow from the southeast(see Wilson and Costelloe, 2011b).

Wilson (2008a, 2011) tabulated the bathyal benthonic foraminif-era in two piston cores from the NE edge of the Grenada Basin(En20-2, 17°50′N, 63°1′W, water depth 680 m; En20-10. 17°02.2′N,63°03.3′W, water depth 885 m; see Reid et al., 1996). The shallowerwater core En20-2 contained an assemblage comparable to the low-

A

B

Fig. 1. The Eastern Caribbean Sea. A. General view showing the locations of the Ane-gada Passage and the core of the Orinoco Plume. B. The Leeward Islands showing thelocations of piston cores En20-2, En20-10 and En20-16. Narrow line=200 m bathy-metric contour.

2 B. Wilson / Marine Micropaleontology 86–87 (2012) 1–10

oxygen, high-nutrient fauna recorded by Galluzzo et al. (1990), withBulimina spp. and Uvigerina spp. collectively forming 14.7% of thetotal recovery. However, these two genera formed only 3.3% of thebenthonic foraminifera in the deeper-water core En20-10. Globocassi-dulina subglobosa formed only 5.0% of En20-2 recovery but 16.0% ofrecovery from En20-10, while Nuttallides rugosa was not recoveredfrom En20-2 but was subdominant in En20-10 (8.0% of recovery).This indicates that the two cores, taken only ~100 km apart and atsimilar depths, were recovered from distinct biotic environments.Thus, at least patches or layers with lower nutrient levels exist withinthe low-oxygen, high-nutrient, Bulimina + Uvigerina zone at 1000–2100 m recorded by Galluzzo et al. (1990). Wilson (2008a) noted,however, that in En20-2 the percentage abundance of low dissolvedoxygen, high surface productivity indicators in the benthonic faunadeclined from ~30% of the assemblage at the base of the core to ~5%at the top.

Although sea-levels during the Late Pleistocene and Early Holocenerose abruptly, the benthonic foraminiferal fauna in En20-2 did notchange abruptly at the Pleistocene–Holocene boundary (Wilson,2008a). Instead there was a gradual change from a higher productivityBulimina spp. + Uvigerina spp. assemblage at the base of the core to-wards a lower-productivity Cassidulina spp. + Globocassidulina spp.

assemblage at the top. Wilson (2008a) concluded that this reflected adecrease in surface productivity through the Late Quaternary. Never-theless, diversity and species dominance did not differ significantly be-tween the Late Pleistocene and the Holocene. These signals in thebenthonic assemblages raise the question: Do planktonic foraminiferain the NE Caribbean Sea show similar, small-scale biogeographic andecostratigraphic patterns?

Studies of Pleistocene and Holocene planktonic foraminifera in theCaribbean Sea have typically examined assemblages at single sitesonly (Black et al., 2004, 2007; Le Friant et al., 2008; Messenger et al.,2010). Steph et al. (2009) discerned mixed layer (Globigerinoidesruber, G. sacculifera), intermediate (Globorotalia menardii, G. tumida, G.scitula, Neogloboquadrina dutertrei) and deep water (Globorotalia trun-catulinoides, G. crassaformis) species of planktonic foraminifera fromcore tops throughout the tropical Atlantic Ocean and eastern CaribbeanSea. Martinez et al. (2007) examined theMid to Late Quaternary plank-tonic foraminifera at ODP Site 999A (western Caribbean) and found thatdiversity (asmeasured using the information functionH=−Σpi·ln(pi),where pi is the proportional abundance of the ith species) was de-pressed during glacials due to the development of a deep thermocline.They suggested also that H typically decreases towards land masses.With the exception of Martinez et al. (2007), however, these papersdid not census the entire planktonic foraminiferal assemblage. Thus,the data from them are of limited use in assessing planktonic foraminif-eral biogeography.

Schmuker and Schiebel (2002) examined relationships between themodern planktonic foraminifera near the Lesser Antilles and the hy-drography of the eastern Caribbean Sea. They concluded that salinityis the principal controlling factor. The live fauna near the Anegada Pas-sage, which extends between Anguilla and the British Virgin Islands,and through which oligotrophic Sargasso Sea water flows into the Ca-ribbean Sea, is characterised by higher concentrations of Globorotaliatruncatulinoides relative to the adjacent water masses. This may reflectthe depth of water in the Anegada Passage, G. truncatulinoides being adeep-dwelling species (Steph et al., 2009). Orinoco-influenced waterengulfs the Windward Islands between Tobago and Guadeloupe, flowsacross the Caribbean Sea towards Puerto Rico, and is characterised byincreased proportions of Neogloboquadrina dutertrei. A pink G. ruber +N. dutertrei association is found in warm, low-salinity river plumes(Ufkes et al., 1998). Schmuker and Schiebel (2002) found Globigerinitaglutinata in surface waters of the NE Caribbean Sea to be associatedwith cyclonic eddies. They suggested that G. ruber in surface sedimentattains higher relative frequencies than other species nearer the islandsthan in the open ocean, indicating that this species is more tolerant ofneritic conditions than are others (an observation first made byBandy, 1956, p. 192).

This study examines the planktonic foraminifera from the north-ern Lesser Antilles in three cores of Reid et al. (1996; En20-2, En20-10 and En20-16). In view of the difference between the benthonic fo-raminiferal assemblages in En20-2 and En20-10 noted above, the de-gree to which the planktonic foraminiferal assemblages in the threecores and in core-top samples differ from one another is assessed.Comparison is made between the ecostratigraphic distributions ofthe high-productivity indicator benthonic foraminiferal group andplanktonic foraminifera in core En20-2.

2. Materials and methods

Reid et al. (1996) used piston cores to study Late Quaternary sedi-mentation in the Lesser Antilles. They did not detail the planktonic fora-miniferal paleoecology but based their correlations on the followingplanktonic foraminiferal datums:

(a) the fluctuating abundance of Globorotalia menardii, whichEricson and Wollin (1956, 1968) had surmised was commonin the last interglacial and Holocene (the X and Z intervals

3B. Wilson / Marine Micropaleontology 86–87 (2012) 1–10

respectively) and rare to absent during the last, interveningglacial (Y interval); and

(b) the extinction of Pulleniatina obliquiloculata. This diachronousdatum ranges from ~60 ka in the Gulf of Mexico, through50 ka in the western Caribbean, to ~35 ka in the equatorial At-lantic (Prell and Damuth, 1978). Reid et al. (1996) took it as oc-curring at ~34 ka in the Lesser Antilles.

Samples were taken every 20 cm from the three piston coresEn20-2, En20-10 and En20-16 of Reid et al. (1996), all from middlebathyal depths off the northern Leeward Islands. Cores En20-2 (15samples) and En20-16 (2.87 m long; 16°50.3′N, 61°56.3′W, waterdepth 737 m; 16 samples) were obtained from the magmatic arc plat-form between the eastern limestone and western volcanic arcs of theLesser Antilles double island arc, while core En20-10 (20 samples)came from the back arc WSW of Nevis. Sedimentation rates differedbetween the cores, being highest in core En20-2 and lowest in coreEn20-16. Reid et al. (1996) used closer sample spacing than isemployed in this study, so their planktonic foraminiferal biostrati-graphic subdivisions of the cores are accepted here (Fig. 2).

Workers typically pick planktonic foraminifera from the >150 μmfraction (Kucera, 2007). Here, however, specimens were picked fromthe >125 μm fraction in order to include smaller species (e.g., Globotur-borotalita rubescens, G. glutinata, Globigerinoides cyclostomus). Approxi-mately the same volume of sediment for each sample was picked cleanof unbroken planktonic foraminifera. The specimens, housed at the Pe-troleum Geoscience Unit, University of the West Indies, were picked

Fig. 2. Lithologies and abundance biozones (ABs) for planktonic foraminifera in piston coresboundaries with significant β diversity marked by an asterisk.

and sorted into species or varieties after Rögl and Bolli (1973) andKennett and Srinivasan (1983), but with the following emendations:

1. Neither Rögl and Bolli (1973) nor Kennett and Srinivasan (1983)recognised G. cyclostomus, which is frequently lumped with G. ruber(e.g., Ujiie and Ujiie, 2000). They were differentiated in this study(Fig. 3), with G. cyclostomus having a smaller aperture, a less lobulateperiphery and a consistently thicker and more granular wall.

2. Two forms of G. ruber (pink and white) were distinguished asthese have been shown to be genetically distinct (Darling et al.,1999). All G. cyclostomus were white.

3. Globigerinoides trilobus showed two forms, one with low, slit-likeapertures and the other with high arched apertures. The latterare termed G. trilobus var.

4. The forms that Rögl and Bolli (1973) placed in Globigerina bulloidescf. quadrilatera are here regarded as kummerform G. bulloides, fol-lowing illustrations in Berger (1970).

5. Illustrations by Loeblich and Tappan (1994) suggest that Globotur-borotalita rubescens is highly variable. However, their pl. 208,Figs. 1–3 are of G. cyclostomus (cf. Loeblich and Tappan, 1994, pl.204, Figs. 1–3). Lobulate specimens resembling Loeblich and Tap-pan's pl. 208, Figs. 4–6 are here placed in G. rubescens, whilethose with a thicker wall and less lobulate outline (see Loeblichand Tappan, 1994, pl. 208, Figs. 7–12) are termed G. rubescensvar. Specimens with a high arched aperture reminiscent of Globi-gerinoides tenellus, but lacking supplementary apertures, are hereplaced in Globoturborotalita cf. rubescens. In the type description

En20-2, En20-10 and En20-16, NE Caribbean Sea. Correlation after Reid et al. (1996). AB

A B C

D E F

Fig. 3. Scale in microns. A. Globigerina calida. B. Globigerinoides cyclostomus. C. Globigerinoides ruber. D. Globigerinoides tenellus. E. Globigerina cf. falconensis. F. Globorotaloides hexagonus.

4 B. Wilson / Marine Micropaleontology 86–87 (2012) 1–10

of G. rubescens, Hofker (1956) noted that the test is red to pink.However, Hemleben et al. (1990) and Hilbrecht (1996) recordedwhite G. rubescens at temperate latitudes. White G. rubescens arehere distinguished from pink.

Fig. 4. Dendrogram for planktonic foraminifera in piston cores En20-2, En20-10 and En20-16.

Associations of samples between cores were assessed using Q-modecluster analysis (paired group method) of species forming >4% of therecovery from any one sample. As the number of specimens comprisingthese species varied widely (maximum, 448; minimum, 203),

Sample depths in centimetres, clusters indicated by arrows and numbers in bold at right.

5B. Wilson / Marine Micropaleontology 86–87 (2012) 1–10

clusteringwas carried out using theMorisita coefficient, which is insen-sitive to sample size (Hammer and Harper, 2005). Calculations wereperformed using the freeware PAST of Hammer et al. (2001). Becausethe cores did not all yield the same number of samples, it was not pos-sible to use ANOVA to compare the percentage abundances of speciesbetween them. Mean percentages were compared using multiple Stu-dent's t-tests.

Point, alpha and beta diversity analyses (Whittaker, 1972) wereundertaken for the individual cores, where point diversity is the in-ventory diversity of the community within individual samples, α di-versity is the inventory diversity within habitats, and β diversity isthe differentiation diversity between habitats (Wilson and Costelloe,2011a). Point diversities were computed using the information func-tion H (=−∑[pi∙ ln(pi)]), where pi is the proportional abundance ofthe ith species. Point dominance was calculated using the equitabilityindex E=eH/S. For details of H and E, see Magurran (2004) andHayek and Buzas (2010). Following Wilson et al. (2010), Wilson(2011) and Wilson and Costelloe (2011a,b), abundance biozonesfrom SHE Analysis for Biozone Identification (SHEBI: see Buzas andHayek, 1998) were equated to habitats sensu Whittaker (1972), anabundance biozone (AB) being a body of rock in which the abundanceof a particular species or group of species differs significantly fromthat in adjacent parts of the section. During SHEBI, samples are accu-mulated in turn through the core and N, S, H and E recalculated fol-lowing the addition of each sample. The boundary between twoadjacent ABs is marked by a change in slope on a graph of lnE vs.lnN. Once an AB boundary has been determined, SHEBI is commencedagain, the first sample above the AB boundary now forming the firstsample in the new SHEBI. SHEBI was applied from the base of eachcore upwards (Wilson, 2008b). The final value of H calculated duringthe determination of the AB boundary (i.e., the value for the sum ofthose samples comprising an AB) was used to derive its α diversity,which was expressed in terms of “the effective number of species” SE(seeMacArthur, 1965), where SE=eH (Jost, 2006, 2007), the numeratorin the equitability index E. Where all species in an AB are equally abun-dant, SE=S (that is, the effective number of species is equal to the actualnumber of species picked from the AB). Where species differ in propor-tional abundance, SEbS. The greater the dominance by one or a few spe-cies, the lower the value of E and the smaller the α diversity.

The α diversities were used to quantify the β diversities betweenpairs of successive ABs. Jost (2007) has demonstrated that comparingeffective numbers of species more reliably quantifies β diversitiesthan do comparisons of H. Using SE1 and SE2 to signify the effectivenumber of species in the older and younger, successive ABs respec-tively (that is, their respective α diversities), β=SE2/SE1 was comput-ed to give a fractional measure of the diversity change between them.Where βb1, the α diversity of the younger AB is less than that of theolder, whereas β=1 occurs where the α diversities do not differ.Where β>1, there was an increase in the α diversity. Note that β isboth dimensionless and non-linear. The significance of each β diversi-ty was determined using the t-test developed for the raw informationfunction H by Hutcheson (1970), in which

t ¼ H1–H2ð Þ= var:H1 þ var:H2ð Þ1=2

and for which

df ¼ var:H1 þ var:H2ð Þ2= var:H1ð Þ2=N1 þ var:H2ð Þ2=N2

h i

where

var:H ¼ Σpi lnpið Þ2– Σpi�lnpiÞ2=N− S−1ð Þ=2 N2� i

:h

Each AB boundary was placed into one of three categories (Wilsonand Costelloe, 2011a). At Type 0β AB boundaries, Hutcheson's (1970)

t-test does not reveal any difference in raw H for the α diversities andβ is ~1. For the other two AB boundary types, Hutcheson's (1970) t-test is significant and β>1 at Type +1β boundaries, while βb1 atType-1β boundaries.

Beta diversity compares α diversities in successive ABs. It does notassess the change in taxonomic composition across the AB boundary.Thus, two ABs containing very different assemblages but similar vectorsof species abundances will be separated by a Type 0β boundary. To as-sess the difference between two ABs in terms of the communities theysupport, complementarity sensu Vane-Wright et al. (1991) was calcu-lated. This study determined complementarity using a modification ofWhittaker's (1952) percentage similarity index CP, in which

CP ¼ 100–0:5Σ pi2–pi1j j;

where pi1 and pi2 are the percentage abundances of the ith species inthe lower and upper AB respectively. Abundance boundaries are moreor less permeable to species' migrations, depending on the differencein the environmental milieu across the boundary (Strayer et al., 2003).Values of CP indicate permeability. Where two assemblages are identi-cal, CP=100 and the AB boundary is completely permeable. Wherethe boundary is a completely impermeable barrier, CP=0.

3. Results

A total of 14,668 specimens of 48 species of planktonic foraminiferawere obtained from the three cores (Appendix; Data repository). Mostspecies were rare, however, with only 21 forming >4% of the recoveryfrom any one sample.

3.1. Whole core comparisons

The mean point diversity, measured using the information func-tion H, was ~2.4 in each core. The higher standard deviation forpoint H in En20-16 (SD=0.25) compared to the other two cores(both SD=0.16) indicates that point diversities fluctuated morewidely in the most south-easterly core. Total recovery was dominatedby white G. ruber (19. 6%), with subdominant G. cyclostomus (14.5%)and white G. rubescens (10.1%).

Cluster analysis was performed using the 21 species forming >4%of any one sample. Setting the phenon line at 0.82, cluster analysis re-veals six clusters (1–6; Fig. 4). These contained the followingsamples:

1. Cluster 1, twelve samples from En20-162. Clusters 1–3, all sixteen samples from En20-163. Cluster 4, fifteen samples from En20-104. Cluster 5, the remaining five samples from En20-10 but twelve

from En20-25. Cluster 6, the remaining three samples from En20-2.

Multiple Student's t-tests were conducted on the mean percent-age abundances of selected abundant species in the three cores(Table 1). White G. ruber differed in abundance between all threecores, being most abundant in En20-2 and least in En20-16. Otherspecies were equally abundant in a pair of cores but differed marked-ly in the third. While G. rubescens (white) was approximately twice ascommon in En20-2 as in the other cores, G. cyclostomus was abouthalf as common in En20-2 as in the other cores.

Bottom-up SHEBI indicated that each core contains several abun-dance biozones (ABs; Table 2; Fig. 2). En20-2 comprised seven ABs(from the bottom up, 2A–2G), En20-10, eight (10A–10H) and En20-16, five (16A–16E). Alpha diversity varied between SE=8.3 (AB 2E)and 14.3 (AB 16B) effective species. Student's t-test did not reveal anydifference in mean α diversities between the three cores (En20-2,mean α diversity=11.7 effective species; En20-10, 12.4 effectivespecies; En20-16, 13.1 effective species). The seventeen β

Table 3Beta diversities across abundance biozone boundaries in piston cores En20-2, En20-10and En20-16. Significant β diversities in bold.

Core Abundance biozone boundary Beta t df

En20-2 2F\2G 0.85 0.91 426.22E\2F 1.54 2.41 441.32D\2E 0.65 2.37 461.02C\2D 1.03 0.17 1082.62B\2C 0.91 0.64 1097.62A\2B 1.19 0.93 489.5

En20-10 10G\10H 1.25 1.33 404.310F\10G 0.90 0.55 579.310E\10F 1.07 0.43 1028.810D\10E 0.85 1.07 1051.110C\10D 1.19 0.94 475.310B\10C 0.89 0.63 474.610A\10B 1.02 0.12 1210.1

En20-16 16D\16E 1.17 1.17 1374.816C\16D 0.92 0.68 1323.316B\16C 0.87 1.29 2248.016A\16B 1.02 0.23 2616.4

Table 1Mean percentage abundances of selected species in piston cores En20-2, En20-10 andEn20-16. Statistically indistinguishable percentage abundances in bold.

Species Core Number ofsamples

Meanpercentage

Standarddeviation

Globigerinita glutinata En20-2 15 4.3 2.4En20-10 20 3.4 3.8En20-16 16 11.0 5.7

Globigerinoidescyclostomus

En20-2 15 7.5 2.8En20-10 20 17.3 5.6En20-16 16 16.6 5.0

Globigeirnoides ruber(pink)

En20-2 15 3.1 2.9En20-10 20 8.0 5.0En20-16 16 11.8 5.7

Globigerinoides ruber(white)

En20-2 15 30.8 8.5En20-10 20 24.5 6.2En20-16 16 7.2 3.2

Globoturborotaliarubescens (pink)

En20-2 15 2.2 2.0En20-10 20 1.3 1.2En20-16 16 16.6 6.6

Globoturborotaliarubescens (white)

En20-2 15 14.8 7.2En20-10 20 7.1 4.6En20-16 16 8.9 5.8

Turborotalita humilis En20-2 15 2.7 1.3En20-10 20 2.3 3.2En20-16 16 0.2 0.3

6 B. Wilson / Marine Micropaleontology 86–87 (2012) 1–10

diversities ranged between 0.65 and 1.54 (Table 3), but only twowere statistically significant, both in En20-2, and reflected thelow α diversity of 8.3 effective species in AB 2E of core En20-2.Thus, there was one each of AB boundary Types −1β (AB bound-ary 2D\2E) and +1β (2E\2F), the remaining fifteen being Type 0βboundaries that show that most α diversities did not differ signif-icantly between ABs. Complementarities ranged from 64.7 to87.6%, across the 10B\10 C and 16D\16E AB boundaries respective-ly (Table 4). The mean complementarity in En20-16 (85.7%) wassignificantly greater than that in En20-10 (75.0%; t=3.01, df=9,pb0.05), which in turn was statistically indistinguishable fromthat at En20-2 (76.9%). The complementarities for the Type −1β(74.4%) and Type +1β (79.6%) boundaries, both of which oc-curred in core En20-2, differed little from the mean complemen-tarity for that core and were not the lowest complementarities withinit (2F\2G, 65.3%). Only a few species showedmaximumabsolute changes

Table 2Alpha diversities of abundance biozones (ABs) in piston cores En20-2, En20-10 andEn20-16. Alpha diversity is stated as both the information function (H) and the effec-tive number of species (SE). N=the number of specimens representing an AB;S=number of species recovered from the AB; var. H=variance of H in a given AB.

Core Abundancebiozone

No. ofsamples

N S Alpha(as H)

Var. H Alpha(as SE)

En20-2 2G 1 255 24 2.37 0.026 10.72F 4 1038 37 2.54 0.008 12.72E 1 255 24 2.11 0.024 8.32D 3 782 29 2.54 0.009 12.72C 2 509 31 2.52 0.014 12.42B 3 836 32 2.61 0.009 13.62A 1 276 27 2.44 0.025 11.5

En20-10 10H 6 1531 40 2.64 0.005 14.010G 1 277 24 2.41 0.024 11.110F 2 555 32 2.52 0.013 12.410E 2 483 27 2.45 0.014 11.510D 3 813 27 2.61 0.009 13.610C 1 266 23 2.43 0.025 11.410B 3 799 29 2.55 0.009 12.810A 2 562 30 2.53 0.013 12.6

En20-16 16E 3 854 25 2.59 0.008 13.316D 2 615 23 2.43 0.010 11.316C 3 1071 32 2.52 0.006 12.416B 3 1193 34 2.66 0.006 14.316A 5 1699 39 2.64 0.004 14.0

in percentage abundance across AB boundaries (in rank order, number ofmaximum absolute changes in parentheses: G. rubescens (white,8 boundaries), G. ruber (white, 7), G. cyclostomus (5), N. dutertrei blowi(3), G. ruber (pink, 3), G. rubescens (pink, 3), N. dutertrei dutertrei (2), G.immaturus (1), G. trilobus var. (1), T. humilis (1)). Themaximum increasefor any species across any AB boundary was 16.0% (G. rubescens (white),AB boundary 2F\2G), while the maximum decrease was -17.0% (G. ruber(white), 2F\2G; G. rubescens (white), 2A\2B). However, application of si-multaneous confidence intervals (Lamboy and Lesnikowska, 1988)showed all themaxima, whether increases or decreases, to be statistical-ly significant.

The percentage abundances of planktonic foraminifera repre-sented by >1% in any one En20-2 sample were compared with thepercentage of the benthonic assemblage per sample as high surfaceproductivity indicators. Positive and statistically significant correla-tions were found between benthonic high-productivity indicators(Bulimina spp. + Uvigerina spp.) and Globigerinella aequilateralis(r=0.58), G. glutinata (r=0.57) and Globorotalia inflata (r=0.57),and significant but negative correlations between the percentage ofbenthonic high-productivity indicators and Globigerinoides immaturus(r=−0.67), G. trilobus var. (r=−0.69) and Globorotalia tumida(r=−0.51). The correlation between the percentage of benthonichigh-productivity indicators and the percentage of the planktonicassemblages as G. menardii (r=−0.43) was not statisticallysignificant.

3.2. Core top comparisons

The cores cover different stratigraphic intervals, En20-2 rangingback only as far as the glacial menardiform Zone Y1 and En20-16 asfar as the interglacial Zone X. It might be suggested that the differ-ences in the mean percentages of species noted for the entire recov-eries from the whole cores (Table 1) reflect the differing amounts ofsediment from glacial and interglacial times within the cores. Forcomparison, the percentages of species in the three core-top sampleswere compared (Table 5). Only six species or varieties formed >10%of the specimens picked from any one sample, but these served to dis-tinguish the sample sites. G. cyclostomus formed >10% in all threesamples (mean 15.4%, s.d. 3.6%), while G. glutinata was most abun-dant in En20-16. G. ruber (white) formed >10% of the specimensfrom En20-2 and En20-10, while G. ruber (pink) formed >10% ofthose from En20-10 and En20-16. G. rubescens (white) were mostabundant in En20-2 and G. rubescens (pink) in En20-16. This core-top pattern broadly resembles that for the whole cores. Consideringthe entire cores and core-top samples, G. glutinata was abundant(>10%) in En20-16 in both the core-top sample and throughout the

Table 4Complementarities across abundance biozones boundaries in piston cores En20-2, En20-10 and En20-16. Also indicated are species showing the maximum increase and decrease inpercentage abundance across each abundance biozone boundary.

Core AB boundary Complementarity (%) Maximum increase (%) Maximum decrease

En20-2 2F\2G 65.3 Globoturborotalita rubescens (white) (16.0) Globigerinoides ruber (white) (−17.0)2E\2F 79.6 Globoturborotalita rubescens (white) (4.0) Globigerinoides ruber (white) (−13.0)2D\2E 76.4 Globigerinoides ruber (white) (15.4) Neogloboquadrina dutertrei dutertrei (−4.4)2C\2D 87.2 Neogloboquadrina dutertrei blowi (4.9) Globigerinoides cyclostomus (−3.6)2B\2C 81.0 Globigerinoides ruber (white) (5.5) Neogloboquadrina dutertrei blowi (−5.3)2A\2B 71.8 Neogloboquadrina dutertrei blowi (6.0) Globoturborotalita rubescens (white) (−17.0)

En20-10 10G\10H 70.7 Globigerinoides immaturus (6.3) Globigerinoides ruber (white) (8.7)10F\10G 83.3 Globigerinoides ruber (pink) (3.3) Globoturborotalita rubescens (white) (−5.5)10E\10F 81.5 Globoturborotalita rubescens (white) (5.8) Neogloboquadrina dutertrei dutertrei (−4.4)10D\10E 80.3 Globigerinoides cyclostomus (3.7) Turborotalita humilis (−6.6)10C\10D 72.0 Globigerinoides cyclostomus (6.2) Globoturborotalita rubescens (white) (−9.3)10B\10C 64.7 Globigerinoides ruber (white) (9.7) Globigerinoides cyclostomus (−16.1)10A\10B 72.5 Globoturborotalita rubescens (white) (6.9) Globigerinoides ruber (pink) (−6.3)

En20-16 16D\16E 87.6 Globigerinoides trilobus var. (2.6) Globoturborotalita rubescens (pink) (−3.4)16C\16D 83.6 Globigerinoides ruber (pink) (5.5) Globoturborotalita rubescens (white) (−4.8)16B\16C 87.1 Globoturborotalita rubescens (pink) (5.6) Globigerinoides cyclostomus (−2.5)16A\16B 84.4 Globigerinoides ruber (white) (5.0) Globoturborotalita rubescens (pink) (−7.2)

7B. Wilson / Marine Micropaleontology 86–87 (2012) 1–10

core, as was G. ruber (white) in En20-2 and En20-10, G. rubescens(pink) in En20-16 and G. rubescens (white) in En20-2.

4. Discussion

Planktonic foraminifera have long been known to live inlatitudinally-arranged bands, discernable at both assemblage (Bé,1977) and species (Hilbrecht, 1996) levels. Assemblage composition

Table 5Percentage abundances of species in core-top samples from piston cores En20-2, En20-10and En20-16.

Species En20-2 En20-10 En20-16

Candeina nitida 0.0 0.0 2.0Globigerina bulloides 2.0 0.4 0.0Globigerina cf. falconensis 0.0 1.1 0.0Globigerina quinqueloba 0.0 0.0 0.3Globigerina spp. 0.0 0.0 0.7Globigerinella aequilateralis 0.0 0.4 0.7Globigerinella siphonifera 0.0 0.0 2.6Globigerinita glutinata 2.0 0.7 14.8Globigerinoides conglobatus 1.6 0.0 0.7Globigerinoides cyclostomus 13.3 19.6 13.2Globigerinoides elongatus 1.2 0.7 0.0Globigerinoides immaturus 8.2 7.1 3.9Globigerinoides pyramidalis 0.4 0.4 0.3Globigerinoides ruber (pink) 0.8 10.3 14.1Globigerinoides ruber (white) 16.9 23.5 7.6Globigerinoides sacculiferus 2.7 8.5 6.3Globigerinoides trilobus 0.4 0.0 0.0Globigerinoides trilobus var. 4.3 4.3 2.3Globorotalia crassaformis ronda 0.0 0.4 0.0Globorotalia cultrata 0.0 3.2 1.6Globorotalia fimbriata 0.0 0.7 0.3Globorotalia menardii 1.2 0.0 0.0Globorotalia scitula 0.0 0.0 0.3Globorotalia truncatulinoides 1.6 1.1 0.7Globorotalia tumida 1.2 1.4 0.3Globorotalia ungulata 0.0 1.1 0.3Globotruborotalita rubescens var. 1.2 0.0 0.0Globoturborotalita rubescens (pink) 5.1 3.2 12.8Globoturborotalita rubescens (white) 29.8 3.2 7.6Globoturborotalita tennellus 2.0 0.0 0.0Neogloboquadrina dutertrei blowi 0.8 3.6 0.7Neogloboquadrina dutertrei dutertrei 1.6 3.9 2.0Neogloboquadrina pachyderma? 0.0 0.0 0.3Orbulina universa 0.8 0.0 3.0Pulleniatina finalis 0.4 1.4 0.7Turborotalita humilis 0.8 0.0 0.0

within these bands has been shown to be modified by surface currents(Cifelli and Smith, 1970; Ujiie and Ujiie, 2000), distance from shore(Bandy, 1956; Schmuker, 2000), upwelling (Tedesco and Thunell,2003) and inflow from rivers (Schmuker and Schiebel, 2002). Althoughthe Quaternary planktonic foraminifera of the Caribbean Sea have along history of study, most papers report trends at single sites (e.g.,core 267 in Phleger et al., 1953) and frequently record selected speciesonly (Reid et al., 1996; Messenger et al., 2010). Martinez et al. (2007)and Black et al. (2004, 2007) placed their findings within an oceano-graphic context, noting especially the effects of upwelling (see alsoTedesco and Thunell, 2003), but were not able to comment on detailedplanktonic foraminiferal biogeography. Comparisons between plank-tonic and benthonic assemblages in the eastern Caribbean have so farbeen lacking.

Wilson (2011) compared the benthonic foraminiferal assemblages incores En20-2 and En20-10 and found that the assemblages in En20-2were consistently indicative of lower dissolved oxygen and higher nutri-ent levels than in En20-10, nutrients being derived from the rain ofplanktonic material. The planktonic foraminiferal faunas in these coreswere compared to assess if any of the species present can be used as in-dicators of high surface productivity. Cluster analysis thus separates coreEn20-16 entirely from cores En20-2 and En20-10, which in turn showonly slight overlap within Cluster 5, while multiple Student's t-testsrevealed considerable and significant differences in species abundancesbetween the cores (Table 1). The total planktonic foraminiferal assem-blage taken from the low-nutrient core En20-2 is impoverished in G.cyclostomus compared to En20-10, but this was not so for the core-topsamples, in which the percentage abundance of G. cyclostomus differedlittle. In contrast, both the total En20-2 assemblage and the core top sam-ple fromEn20-2was enriched inG. rubescens (white) compared to En20-10, suggesting that this species might be used as an indicator of surfaceproductivity.

The positive correlations in En20-2 between the percentage abun-dance of low dissolved-oxygen, high surface productivity indicators inthe benthonic fauna and the percentages of Globigerinella aequilateralis,G. glutinata and G. inflata suggests that these have potential asindicators for high surface productivity. In contrast, negativecorrelations with G. immaturus, G. trilobus var. and Globorotalia tumidasuggest that these are indicative of low surface productivity. Thesecorrelations may be related to an enhanced organic flux in glacial timesand in turn related to greater sea surface productivity (the ‘planktonmultiplier’ of Woods and Barkmann, 1993). The insignificantcorrelation between the percentage of benthonic high-productivity indi-cators and the percentage ofG.menardii suggests thatfluctuations in sur-face productivity affect this species little. It has instead long been used as

8 B. Wilson / Marine Micropaleontology 86–87 (2012) 1–10

an indicator of fluctuations in sea surface temperatures (Ericson andWollin, 1956).

Bottom-up SHEBI found each core to contain several abundance bio-zones (ABs). Comparison with accepted biostratigraphic markers – themenardiform zones of Ericson and Wollin (1968) and the 34 kaextirpation of Pulleniatina obliquiloculata of Prell and Damuth (1978) –indicates that these ABs cannot be used to correlate the three cores(Fig. 2). En20-16 contained the fewest ABs despite being the only coreto range back to menardiform Zone X (the last interglacial).

Martinez et al. (2007) noted that at ODP Site 999A (westernCaribbean Sea) the information function H was depressed during gla-cials. This phenomenon, which would be reflected in point diversities,was not found in the three cores examined here. Nor was it reflectedin β diversities, which were almost all of Type 0β and thus indicatedthat α diversities did not differ significantly between successive abun-dance biozones (ABs). As indicated by complementarities (Table 4),the AB boundaries mostly arose from changes in the relative abun-dances of species.

Schmuker (2000) examined the distribution of planktonic forami-nifera in sediment samples taken ~ 0.5–42 km (not –0.5) beyond theshelf edge south of Puerto Rico, west of the Lesser Antilles. His assem-blages came from (a) post glacial core tops ~800–2500 years old and(b) selected samples ~30 cm deep within his cores. He recorded thata “Globigerinoides ruber group” (=white and pink G. ruber + G.cyclostomus of this study) formed 46–67% of the fauna throughoutand increased in abundance along a transect from the open sea to-wards the shelf edge off Puerto Rico. Members of this group beingnear-surface dwellers (Steph et al., 2009, Fig. 4), they would beexpected to dominate sediment assemblages beneath shallow waterat the expense of deeper dwelling species. Reid et al. (1996) showthat, of the three cores examined in this study, En20-2 was taken clos-est to the 200 m contour and En20-10 farthest from it (Fig. 1), al-though all were at middle bathyal depths. Within the entire cores,the mean percentage of total planktonic foraminiferal assemblagesformed by the “G. ruber group” was lowest in En20-16 (35.7%;737 m water depth), intermediate in En20-2 (41.5%; 680 m) andhighest in En20-10 (49.8%; 885 m). Student's t-tests did not find anydifference in the mean percentage abundance of the “G. rubergroup” between En20-2 and En20-16, but showed the percentage inEn20-10 to be significantly greater than both. Within the core-topsamples only, the “G. ruber group” was most abundant in En20-10(~54%), and approximately equally abundant in En20-2 and En20-16 (31% and 35% respectively). Thus, the pattern of abundances inthe core-top samples closely matches that in the entire cores, eventhough the cores cover time intervals of different durations. En20-10 being farthest from the shelf edge, these findings are at variancewith Schmuker's (2000) finding that the percentage of the “G. rubergroup” increases towards the shore off Puerto Rico. Furthermore,the abundance of the “G. ruber group” increased with water depth de-spite the expectation that this would contain greater numbers of deepdwelling species. Finally, they suggest that the factors responsible forthe greater abundance of the “G. ruber group” at En20-10 persistedthroughout the Late Quaternary.

It might be argued that these results are skewed by the use ofthe >125 μm fraction in this study compared to the >150 μmused by Schmuker (2000). Other comparisons suggest, however,that the use of different size fractions probably did not influence the re-sults greatly. Schmuker (2000) reported that off Puerto Rico, whitespecimens of his “G. ruber group” (=G. ruber (white) + G. cyclostomusof the present study) formed ~66% of that group. The percentage of the“G. ruber group” as white specimens was higher in the northern LesserAntilles, G. ruber (white) + G. cyclostomus forming a mean of 81.7% ofthe total “G. ruber group” in the three cores examined in this paper. Itwas high in En20-2 (mean, 93.0%) and En20-10 (84.4%), although Stu-dent's t-test indicated that the mean percentage in En20-2 was signifi-cantly greater than that in En20-10 (t=3.21, df=33, pb0.05). It was

markedly lower in En20-16 (68.0%). Thus, the percentage ofwhite spec-imens in the “G. ruber group” differed between the three cores and,being lowest in En20-16, was not a function of distance from the200 m bathymetric contour. Furthermore, it was markedly higher inEn20-2 and En20-10 than in any sample collected by Schmuker(2000) off Puerto Rico.

When the white-walled components of Schmuker's (2000) “G.ruber group” are examined separately, the percentage of the entireplanktonic assemblage as G. ruber (white) is found to differ betweenall three cores, being highest in En20-2 and lowest in En20-16. In con-trast, G. cyclostomus formed a mean of 16.5–17.5% in En20-10-10 andEn20-16, but only 7.5% in En20-2. Once again, these percentage abun-dances do not reflect distance from the shelf edge. Martinez et al.(2007) suggested that the value of the information function H forplanktonic foraminifera increases with increasing distance fromshore. The mean value of point H was ~2.4 among all three cores ex-amined here.

The distributions of the components of the “G. ruber group” thusshow that there is a NW–SE component to factors affecting distribu-tions. This is reflected in the percentage abundances of other commonspecies. G. glutinata and G. rubescens (pink) are more abundant inEn20-16 than in the other cores, while G. rubescens (white) and Tur-borotalita humilis are less abundant. It is also indicated by clusteranalysis, which entirely separated En20-16 from the other two coresbut did not entirely separate En20-2 and En20-10. A similar phenom-enon was noted from cluster analysis of bathyal benthonic foraminif-era in En20-2 and En20-10 (Wilson, 2011), which showed that thetwo cores came from different biotic environments.

Ujiie and Ujiie (2000, Fig. 8) found that the Kuroshio Current off theRyukyu island arc, NW Pacific Ocean, exerted a strong control over thedistribution of planktonic foraminiferal assemblages. It might be sug-gested that differences between the planktonic foraminiferal assem-blages in the three cores from the Lesser Antilles are similarly relatedto regional oceanography. Both En20-2 and En20-10 lie on trend withthe Anegada Passage, through which oligotrophic surface water fromthe Sargasso Sea enters the Caribbean Sea (Fratantoni et al., 1997).However, benthonic foraminifera indicate that En20-10, which wasdrawn fromdeeperwater than En20-2,was taken from a lower produc-tivity area. En20-16, meanwhile, lies somewhat to the east of En20-2and En20-10, and comparison with surface currents mapped byGordon (1967) shows En20-16 to lie in the path of a Caribbean Currentderived from the SE. Wilson and Wilson (2011) suggested that ben-thonic foraminiferal propagules were dispersed by this current whenexplaining the similarity of nearshore foraminiferal assemblagesthroughout the Lesser Antilles. Thus, the distributions of benthonicand planktonic foraminifera show the northern Lesser Antilles to bean area of considerable oceanic complexity. This is further reflected by(a) the abundance biozones (ABs) detected using SHEBI and (b) com-plementarities. The ABs cannot be used to correlate between thecores, while complementarities show that the assemblages in thethree cores developed independently.

5. Conclusions

Planktonic foraminiferal assemblages within three bathyal pistoncores taken from the Late Quaternary of the northern Lesser Antillesand ~150 km apart differed markedly and were mirrored by differ-ences in associated benthonic foraminifera that suggest closelyspaced variations in surface productivity. The differences in theplanktonic community were not related to distance from the 200 mbathymetric contour, here equated with the shelf edge, and so arehypothesised to be related to local oceanographic conditions. SHEAnalysis for Biozone Identification (SHEBI) indicated each core tocomprise a succession of assemblage biozones (ABs). Comparisonwith biostratigraphic datums (G. menardii, Pulleniatina obliquilocu-lata) showed each core to contain a different set of ABs such that

9B. Wilson / Marine Micropaleontology 86–87 (2012) 1–10

ABs could not be used to correlate between the cores. The AB bound-aries were not coincident with glacial-interglacial boundaries, as indi-cated by abundances of G. menardii, which suggests that thedevelopment of abundance biozones is not simply a function of vari-ations in paleotemperature. Analyses of changes in diversity (α and βdiversities) indicated that diversities changed little throughout thecores, while complementarities showed the AB boundaries to reflectchanges in species' abundances that did not impact on α diversity.

There have been few studies of bathyal and deeper water ben-thonic foraminifera in the Late Quaternary and Recent of the easternCaribbean Sea. Likewise, planktonic foraminifera have been littlestudied. The results from this study show the northern Lesser Antillesto be an area of considerable complexity with regard to the distribu-tions of both late Quaternary planktonic and benthonic foraminiferalassemblages. It is hoped that these observations will lead to furtherwork examining foraminiferal distributions throughout the LesserAntilles.

Supplementary materials related to this article can be found on-line at doi:10.1016/j.marmicro.2011.12.002.

Acknowledgments

Thanks are due to Steven Carey of the University of Rhode Island,Graduate School of Oceanography, who made the material from boththese cores available. Michal Kucera, Tübingen, Germany, and ananonymous second reviewer made much appreciated and valuablecomments on earlier versions of this paper.

Appendix A

#=species forming >4% of planktonic foraminiferal recoveryfrom at least one sample. For reference details, see Ellis and Messina(1940 et seq.)

Beella digitata (Brady)=Globigerina digitata Brady, 1884Candeina nitida d'Orbigny, 1839#Globigerina bulloides d'Orbigny, 1826Globigerina calida Parker, 1962Globigerina cf. falconensis Blow, 1959Globigerina quinqueloba Natland, 1938Globigerina spp.Globigerinella aequilateralis (Brady)=Globigerina aequilateralis

Brady, 1897#Globigerinella siphonifera (d'Orbigny)=Globigerina siphonifera

d'Orbigny, 1839#Globigerinita glutinata (Egger)=Globigerina glutinata Egger,

1895Globigerinoides conglobatus (Brady)=Globigerina conglobata

Brady, 1884#Globigerinoides cyclostomus (Galloway and Wissler)=Globiger-

ina cyclostoma Galloway and Wissler, 1927Globigerinoides elongatus (d'Orbigny)=Globigerina elongata d'Or-

bigny, 1826#Globigerinoides immaturus LeRoy=Globigerinoides sacculiferus

(Brady) var. immatura LeRoy, 1939#Globigerinoides pyramidalis (van der Broeck)=Globigerina bul-

loides d'Orbigny var. rubra d'Orbigny subvar. pyramidalis van derBroeck, 1876

#Globigerinoides ruber (pink) (d'Orbigny)=Globigerina rubrad'Orbigny, 1839

#Globigerinoides ruber (white)=pars. Globigerina rubra d'Orbigny,1839

#Globigerinoides sacculiferus (Brady)=Globigerina sacculiferaBrady, 1877

Globigerinoides sp. indet.Globigerinoides tennellus Parker, 1958 (Globigerinoides tenella in

original paper)

Globigerinoides trilobus (Reuss)=Globigerina triloba Reuss, 1850#Globigerinoides trilobus var.#Globorotalia crassaformis crassaformis (Galloway and Wissler)=

Globigerina crassaformis Galloway and Wissler, 1927Globorotalia crassaformis ronda Blow=Globorotalia (Turborotalia)

crassaformis ronda Blow, 1969#Globorotalia cultrata (d'Orbigny)=Rotalina cultrata d'Orbigny,

1839Globorotalia fimbriata (Brady)=Pulvinulina menardii (d'Orbigny)

var. fimbriata Brady, 1884#Globorotalia flexuosa (Koch)=Pulvinulina tumida var. flexuosa

Koch, 1923Globorotalia inflata (d'Orbigny)=Globigerina inflata d'Orbigny,

1839Globorotalia menardii (Parker, Jones and Brady)=Rotalia menardii

Parker, Jones and Brady, 1865Globorotalia scitula (Brady)=Pulvinulina scitula Brady, 1882#Globorotalia truncatulinoides (d'Orbigny)=Rotalina truncatuli-

noides d'Orbigny, 1839Globorotalia tumida (Brady)=Pulvinulina menardii (d'Orbigny)

var. tumida Brady, 1877Globorotalia ungulata Bermúdez, 1961Globorotaloides hexagoma (Natland)=Globigerina hexagona Nat-

land, 1938#Globotruborotalita rubescens var.#Globoturborotalita rubescens (white) (Hofker)=Globigerina

rubescens Hofker, 1956#Globoturborotalita rubescens (pink)=Globigerina rubescens

Hofker, 1956Globoturborotalita cf. rubescens Hofker, 1956Globoturborotalita tennellus (Parker)=Globigerinoides tenella Par-

ker, 1958#Neogloboquadrina dutertrei blowi Rögl and Bolli, 1973#Neogloboquadrina dutertrei dutertrei (d'Orbigny)=Globigerina

dutertrei d'Orbigny, 1839Neogloboquadrina incompta (Cifelli)=Globigerina incompta Cifelli,

1961Neogloboquadrina pachyderma? (Ehrenberg)=Aristospira pachy-

derma Ehrenberg, 1861Orbulina universa d'Orbigny, 1839#Pulleniatina finalis Banner and Blow, 1967Sphaeroidinella dehiscens (Parker and Jones)=Sphaeroidina bul-

loides (d'Orbigny) var. dehiscens Parker and Jones, 1865Tenuitella iota (Parker)=Globigerinita iota Parker, 1962#Turborotalita humilis (Brady)=Truncatulina humilis Brady, 1884

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