On the discovery of a Cretaceous representative of the extant marine
interstitial genus Iliffeoecia Maddocks, 1991 (Ostracoda, Pontocyprididae)
KAREL WOUTERS
Koninklijk Belgisch Instituut voor Natuurwetenschappen.
Vautierstmat 29,
B-1000 Brussels,
Belgium
ABSTRACT_____________
The genus Iliffeoecia, described by Maddocks (1991) from anchialine caves in Bermuda and from the Galapagos Islands, was
recently rediscovered (I. varnensis sp. nov.) in shallow sediments trom the Maldive Islands and from Papua New Guinea.
Detailed study of material of Cardobairdia rectimargmata Nuyts, 1990 from Cretaceous deposits in Belgium and the
Netherlands, revealed that this species also belongs to the genus Iliffeoecia. This observation extends the range of the genus
from Lower Cenomanian to Recent. Comparison of the two extant species with the Cretaceous one show s that m orphologi­
cal differences are very small. Little information is available on the age of interstitial faunas. This is the second time that
interstitial extant ostracods were show n to have strongly resembling Cretaceous congeners. It illustrates the stability of the
interstitial environm ent over long periods of time, and the importance of morphological stasis in low diversity lineages.
Proceedings of 2nd. European Ostracodologists Meeting, Glasgow 1993, British Micropalaeontological Society, London, 16th
December 1996, 57-62.
sinuous, unbranched; p o sterio r m arginal p ore canals short. M uscle
scar p a tte rn sm all, consisting of five oval scars; curved anterior row
of three scars a n d tw o p o sterior scars.
A ntennule large, broad, 8-segm ented; segm ents 4 a n d 5 flexibly
articulated; set w ith long claw -like setae. A ntenna robust, five-seg­
m ented; sw im m ing setae short; Y-aesthetasc large a n d inflated; ter­
m inal setae claw-like. M andible: g n athobase w ith n u m ero u s slender
teeth, som e bifid; dorso-distal o u ter se ta strongly d eveloped and
distally ending in 4 or 5 tooth-like setae. Palp four-segm ented w ith
long, curved term inal claws, en d in g in a sm all hook.
M axillule: vibratory p late w ith a bout 16 norm al Strahlen, a n d four
aberrant, m o u th w ard directed ones; first e n d ite w ith strong ventrally o riented tooth.
M axilla (PI): e n d o p o d ite sm all, a n d w ith o u t distinctive segm enta­
tion; only one term inal seta.
W alking leg (P2): five-segm ented, w ith a long term inal claw.
C leaning lim b (P3): four-segm ented; term inal segm ent w ith three
term inal a n d one subterm inal seta; tw o term inal setae sm ooth and
longer th an term inal segm ent, the th ird one strongly pectinate, as
long as the term inal segm ent.
Furca: very sm all, w ith strongly reduced shaft, a n d w ith 6 w eakly
d eveloped setae; the antero-distal seta is very sm all a n d h ard ly visi­
ble. M ale: unknow n.
D im ensions.
H olotype: L. 0.33 m m , H . 0.14 m m
Paratype: L. 0.35 m m , H . 0.15 m m
Remarks. U p to now o nly three species of the gen u s Iliffeoecia have
been described. I. iliffei M addocks, 1991 strongly resem bles the new
species described here, b u t differs in a few details. T he antero-ven­
tral inner lam ella of I. iliffei is m ark e d ly broader, the fourth segm ent
of the antennule is longer a n d the an te rio r row of a d d u cto r scars is
curved. I. rectimarginata (N uyts, 1990) is som ew hat larger, the
antero-ventral line of concrescence is less sinuous a n d the dorsal and
ventral m argins are tapering less tow ards the posterior extremity.
INTRODUCTION
Interstitial ostracods are u n d errep resen ted in m ost palaeontological
and neontological studies, and very little is k n o w n ab o u t their evo­
lution. In this context, the discovery of a fossil interstitial ostracod is
extrem ely significant because of its evolutionary a n d zoogeographical im plications. In this p a p e r it is show n th a t the g enus Iliffeoecia,
w ith tw o kn o w n extant species, I. iliffei M addocks, 1991 a n d I. varn­
ensis sp. nov. has also a representative, I. rectimarginata (N uyts,
1990), in the Cretaceous of N.W. E urope. The present observations
are coherent w ith P o korny's p a p e r (1989) o n C retaceous interstitial
ostracods from B ohem ia a n d w ith the com m ents m ad e by
D anielopol & W outers (1992) o n this fauna.
SYSTEMATIC DESCRIPTIONS
O rd e r Podocopida Sars, 1866
S u border Podocopina Sars, 1866
Superfam ily Cypridacea Baird, 1845
Fam ily Pontocyprididae M uller, 1894
G enus Iliffeoecia M addocks, 1991
Iliffeoecia varnensis sp. nov.
(PI. 1, figs. 1-11; PI. 2, figs. 1-4)
D erivation of name. A fter the type locality, Villi Varu Island.
H olotype. A fem ale w ith valves (O.C. 1702a) a n d dissected lim bs in
a glycerine prep aratio n (O.C.1702b), M aldive Islands.
Paratype. O ne em pty carapace (O.C.1703) from N . P apua N ew
Guinea, M egiar H a rb o u r (M adang Province, Leg. J. Van Goethem ,
21 July 1981, 81/496).
Type locality. R epublic of the M aldives, South M alé Atoll, Villi
Varu Island, N.W. shore of the island, d e p th 1 m (Leg: Fr. Fiers, 3
Dec. 1984,84/66) (F ig .l).
Description, Valves very sm all, subtrap ezo id al in shape; anterior
m argin b roadly ro u n d ed , p o sterior m arg in truncate; dorsal m argin
straight w ith distinct posterior a n d indistinct a nterior cardinal
angle; ventral m argin straight; dorsal a n d ventral m argins tapering
to w ard s the p o sterio r end. C arapace in dorsal view spindle-shaped;
left valve o verlapping right one; ven tral overlap strongly sinuous.
Valve surface com pletely sm ooth. L ateral pores sim ple, w ith a lip
(type A "of Puri, 1974). Inner lam ella w id e in the anterior half; line
of concrescence sinuous in antero-ventral area; a nterior vestibulum
large a n d bag-shaped; p o sterior vestib u lu m narrow ; m arginal pore
canals num erous, a n d long in antero-ventral area, som e curved o r
Iliffeoecia rectim arginata (N uyts, 1990)
(PI. 1, fig. 12; PI. 2, figs. 5-8)
V 1940 Cytherideis bemelenensis v a n Veen; Bonnem a: 1Í5-116, pl.3,
figs. 38-38 (non v a n Veen, 1936).
1966 Cardobairdia sp.; H errig: 774-775, pl.15, figs. 5-6, text-figs.46-47.
V 1990 Cardobairdia rectimarginata sp. nov.; N uyts: 67, pi. 1, figs. 5-8.
1992 Cardobairdia rectimarginata N uyts; W itte et al.: 49, pi. 2, figs. 8-9.
Material studied. Coli. B onnem a (Rijks G eologische Dienst,
57
Cretaceous and extant Iliffeoecia
Fig. 1. Distribution of Iliffeoecia (circles: Recent; triangles: Cretaceous); 1-2:1, iliffei; 3-4:1, varnensis sp. n.; 5-8: Í. rectimarginata. 1. Bermuda (Maddocks,
1986); 2. Galapagos (Maddocks, 1991); 3. Maldives (this paper); 4. Papua New Guinea (this paper); 5. Borehole De Krim, The Netherlands, Turonian
(Bonnema, 1940); 6. Isle of Rügen, Germany, Lower Maastrichtian (Herrig, 1966); 7. Borehole Knokke, Belgium, Cam panian (Nuyts, 1990); 8. The
Achterhoek area, The Netherlands, Lower Cenomanian (Witte et ah, 1992).
T he g enus Iliffeoecia M addocks, 1991 w as described a n d illustrated
for the first tim e as "N ew genus, n e w species" by M addocks (1986)
on the basis of a single fem ale from W alshingham C ave in the
B erm udas. A bout one year later W outers (1987) recorded the "new
genus" from the M aldive Islands. This species is described here as I.
mruetisis sp. nov. The discovery of a su p p lem en tary fem ale in
C ueva d e la C adeno, G alapagos Islands, led M addocks (1991) to
nam e the n ew genus Iliffeoecia, w ith I, iliffei as its type species. In all
cases representatives of the g enus Iliffeoecia seem to be particulary
rare. O nly one or tw o specim ens w ere fo u n d on each occasion.
Iliffeoecia is the second k n o w n interstitial p o n to cy p rid id genus. The
o ther one is Comontocypris W outers, 1987. It h a s a sm all, inflated,
ventrally flattened, slightly rostrate carapace, externally hom eom orphic w ith som e interstitial cytheraceans. Interstitial ostracods show
som e p articu lar m orphological adaptations.
For m arine ostracods this phen o m en o n is extensively discussed
by H a rtm a n n (1973), M addocks (1978), G ottw ald (1983), H a rtm a n n
(in D anielopol & H artm ann, 1986) a n d D anielopol a n d W outers
(1992). Some of these adap tatio n s are d e m o n stra ted by the genus
Iliffeoecia: absence of eyes a n d reduction of size.
T here is, how ever, no dorso-ventral com pression, a n d the lateral
com pression of the valves is n o t very p ronounced, a n d obviously
n o t v ery different from the related gen u s Argilloecia. The soft p a rts
H aarlem ), 3 valves a n d 6 carapaces, borehole N N IV, D e K rim and
N N 11, Schuinesloot. A ccording to P okom y (1975) the m arls of the
De K rim borehole are of M iddle T uronian to L ow er Santonian age.
Coli. N u y ts (U niversity of G hent), 4 valves, borehole K nokke (N.W
Belgium ), 331.70 a n d 340.70m, U p p er Cam panian'.
A d d itio n a l d escrip tio n . The species is extensively described b y
N u y ts (1990). A few additio n al rem arks are given here: anterior
vestibulum large, w ith nu m ero u s m arginal p ore canals; antero-ven­
tral a n d ventral m arginal pore canals could n o t be seen because of
the relatively b a d preservation of the valves, d u e to recrystallisation. N arrow p o sterior vestibulum , w ith som e sh o rt m arginal pore
canals. In n e r lam ella w id e in the antero-ventral ared, w ith only
slightly sinuous in n er m argin.
M uscle scar p a tte rn u nknow n.
D im en sio n s: L. 0.33-0.42 m m , H . Ö.16-0.20 m m (N uyts, 1990).
O ccurrence. G erm any: L ow er M aastrichtian of R ügen (Herrig,
1966). T he N etherlands: M iddle T uronian to L ow er Santonian o f the
borehole D e K rim (Bonnem a, 1940), L ow er C enom anian of the
A chterhoek area (W itte et a l, 1992). Belgium : borehole Knokke,
low er to U p p erm o st C am panian (N uyts, 1990) (Fig. 1).
R a n g e : L ow er C enom anian - L ow er M aastrichtian.
DISCUSSION
Explanation of Plate 1
Figs 1-11. Iliffeoecia varnensis sp. nov., holotype, female (O.C. 1702a, b), Villi Varu Island, Republic of Maldives; Fig. 1. Antennule: Fig 2. Antenna: Fig 3.
M andibular palp; Fig. 4. Maxilla (PI); Fig. 5. M andibular gnathobase; Fig. 6. Maxillule; Fig. 7. Furca; Fig. 8. Cleaning limb (P3); Fig. 9. Walking leg (P2);
Fig. 10. Muscle scar pattern, RV int.; Fig. 11. LV, int. lat. Fig. 12 Iliffeoecia rectimarginata (Nuyts, 1990), marls of the De Krim Borehole (NN IV), Turonian,
Coli. Bonnema, slide BvV-0.2136, Rijks Geologische Dienst Haarlem: LV, int. Iat.
58
Wouters
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Cretaceous and extant Iliffeoecia
age of the su b terran ean N ainibcypridini (a tribe of the fam ily
C andonidae, fresh w ater). The presen t geographical d istribution of
this tribe indicates th a t spéciation occurred through the vicariant
effect of the opening of the A tlantic, and p o in ts to w ard s a M esozoic
age of th eir direct ancestor. The fossil a n d R ecent occurrence of
Saida, a genus of sedim ent dw elling ostracods, suggests a Tethyan
d istribution du rin g the Cretaceous (M cKenzie, 1973), a n d is com pa­
rable to the distribution of Saipanetta, Pussella a n d Eiffeoecia. W hen
stu d y in g the age of E uropean freshw ater interstitial ostracod fau­
nas, D anielopol (1980) inferred a M io-Pliocene o r ev en Pleistocene
age
for
the
invasion
of
the
hy p o g ean
by
the
P seudolim nocytherinae. This is m uch yo u n g er th an w h at is sug­
gested here for Eiffeoecia. The biogeography of m any m arine
C retaceous-Cenozoic O stracoda h a s b een associated w ith the evolu­
tio n of Tethys by M cKenzie (1967) a n d N eale (1976). Because ostra­
cods h av e a fossil record, m uch m ore in form ation on the evolution­
ary history a n d zoogeography of interstitial anim als can be expect­
ed from the detailed stu d y of interstitial ostracods.
are less affected. T he m ost striking feature is the loss of sw im m ing
setae, b u t this can also b e seen in Argilloecia a n d Australoecia, b oth
bottom dw elling ostracods, probably living as w ell on, as in, the
sedim ent. The m orphological differences betw een Comontocypris
an d Iliffeoecia illustrate the p o in t of view p u t forw ard by D anielopol
& W outers (1992) th a t instead of a w ell defined m arin e interstitial
ostracod m o rphology one can see a variety of adap tatio n s to life in
sandy sedim ents, w ith in the sam e family. A lthough m arin e interstitial ostracods, w ith representatives in a t least 18 different families,
are probably relatively com m on in m o d ern seas, they are only
rarely m entioned in faunistical studies or surveys. This is som ew hat
surprising, because in som e sam ples, stu d ied by the author, from
e.g. P a p u a N ew G uinea o r the M aldives, the ostracod fauna som e­
tim es consists of m ore than 90% of living interstitial ostracods. In
other sam ples this value is m uch lower, b u t in shallow sandy sedi­
m ents or in coralline debris in tropica] seas, interstitial ostracods are
alm ost alw ays present.
This does n o t m ean th a t particu lar g enera a n d /o r species are
com m on. Species of the g enera Pussella, Danipussella, Comontocypris,
Saipanetta, Saida a n d lliffeoeda, for instance, ap p ea r to be rare every­
w here. In the fossil record the situ atio n is even w orse. Interstitial
ostracods are only rarely fo u n d a n d / or recognized as such. The dis­
covery of fossil interstitial ostracods therefore is not w ith o u t im p o r­
tance, because it can shed som e light o n the evolutionary history of
the group.
A n im p o rtan t contribution in this d o m ain w as m ad e by Pokorny
(1989) by describing Saipanetta a n d Pussella species from the
T uronian of Bohem ia. This p a p e r w as com m ented u p o n by
D anielopol & W outers (1992), w h o com pared the fossil species w ith
closely resem bling extant ones. They concluded th a t the striking
resem blance b etw een the Turonian a n d the R ecent species illustrat­
e d the stability o f the m arin e interstitial env iro n m en t o v e r long
p erio d s of tim e, a n d the im portance of m orphological stasis in low
d iversity lineages.
The discovery of Eiffeoecia rectimarginata h a s to be seen in this
context. It is a relatively rare species, w ith an extensive stratigraphical range. It is kn o w n from L ow er C enom anian to Low er
M aastrichtian deposits, and it therefore h a s only a lim ited stratigraphical applicability (Witte et al., 1992). T he com parison betw een
the tw o extant species T. iliffei a n d I. varnensis w ith the Cretaceous I.
rectimarginata show s that there are only sm all m orphological differ­
ences.
The n u m b er of k n o w n R ecent a n d fossil species is low. E ven if the
inform ation available on fossil and R ecent interstitial ostracods is
ra th e r lim ited, it still can b e assum ed th a t Iliffeoecia is a low diversi­
ty lineage in the P ontocyprididae.
O ne of the species (I. rectimarginata) has a rem arkably extensive
stratigraphical range, w hich points into the sam e direction, nam ely
a Sow n u m b er of spéciation events. The distrib u tio n of I. rectimar­
ginata suggests th a t it dispersed along the shallow m argins of
Tethys, w h e n a tropical clim ate prevailed. It has to be stressed, h o w ­
ever, th a t although som e interstitial ostracods, such as pussellids,
Saipanetta, Iliffeoecia, a n d m aybe others, have a long evolutionary
history, going back to the C retaceous, others m ay well be m uch
younger. This m eans th a t the invasion of the interstitial environ­
m en t by ostracods is probably n o t a single event, b u t m ay w ell have
h a p p en e d at different m om ents in tim e fo r different groups. A lm ost
no inform ation is available o n the ev olution a n d age of interstitial
ostracods. M artens (1992) recently form ulated a n hypothesis on the
ACKNOWLEDGEMENTS
The au th o r w o u ld like to express his thanks to Dr. H. N uyts,
U niversity of G hent, for perm ission to stu d y m aterial from his col­
lection, a n d to Dr. L. Witte, Rijks G eologische D ienst, H aarlem , for
the loan of specim ens from the Bonnem a-collection.
REFERENCES
Bonnema, J H., 1940. Ostracoden aus der Kreide des Untergrundes der
Nordöstlichen Niederlande. Natuurhisl. Maandbl, 29, (9-12), 9195,104,108,115-118,129,132.
Danielopol, D.L., 1980. An essay to assess the age of freshwater intersti- ■
tial ostracods of Europe. Bijdr. Dierk., 50 (2), 243-291.
Danielopol, D. & Hartmann, G., 1986. Ostracoda. In: Botosaneanu, L.
(Ed.), Stygofanna mundi, 265-294, Leiden, E.J. Brill/W. Backhuys.
Danielopol, D.L. & Wouters, K., 1992. Evolutionary (Paleo) biology of
marine interstitial Ostracoda. Geobios, 25, (2), 207-211.
Herrig, E., 1966. Ostracoden aus der weissen Schreibkreide (UnterMaastricht) der Insel Rügen. Paläont, Abb., Berlin, A, 2 (4), 693-1024.
Gottwald, ]., 1983. Interstitielle Fauna von Galapagos, XXX. Podocopida
1. (Ostracoda). Mikrofauna Meeresb., 90, 621-803.
Hartmann, G., 1973. Zum gegenwaertigen Stand der Erforschung der
Ostracoden interstitieller Systeme. Ann. Spéléol., 28, (3), 417-426.
Maddocks, R.R, 1976. Pusseliinae are interstitial Bairdiidae (Ostracoda).
Micropaleontol., 22 (2), 194-214.
Maddocks, R.F., 1986. Podocopid Ostracoda of Bermudian Caves,
Stygoiogia, 2 (1/2), 26-76.
Maddocks, R.F, 1991, Revision of the family Pontocyprididae
(Ostracoda), with new anchiaiine species and genera from Galapagos
islands. Zool. ]. Limi. Soc. Lond., 103, 309-333.
Martens, K., 1992. On Namibcypris cosfnfn n. gen., n. sp. (Crustacea,
Ostracoda, Candonidae) from a spring in northern Namibia, with the
description of a new tribe and a discussion on the classification of the
Podocopina, Stygoiogia, 7(1), 27-42.
McKenzie, K.G., 1967. The distribution of Caenozoic marine Ostracoda
from the Gulf of Mexico to Australasia. Syst. Assoc, Publ., 7, 219-238.
McKenzie, K.G., 1973. Cenozoic Ostracoda, in: Hallam, A. (Ed.), Atlas of
Palaeobiogeography, 477-487. Elsevier Scientific Publishing Company,
Amsterdam.
Neale, J.W., 1976. Cosmopolitanism and Endemism - An Australian
Upper Cretaceous Paradox. Abh. Verh. natunoiss. Ver. Hamburg, N.F.,
18/19 suppl., 265-274.
Nuyts, H., 1990. Krausella minuta, a nom en nudum in ostracodology, and
Explanation of Plate 2
Figs. 1-4. Eiffeoecia varnensis sp. nov., X 210: Fig. 1. Holotype (O.C. 1702a), female, LV ext. Iat.; Fig. 2. Holotype (O.C, 1702a), female, LV, int. Ia t; Fig. 3.
Paratype (O.C. 1703), car ext. dors.; Fig. 4. Paratype (O.C. 1703), car ext. ventr. Figs. 5-8. Iliffeoecia rectimarginata (Nuyts, 1990), borehole Knokke, Upper
Campanian, X 200: Fig. 5. LV, ext. Iat.; Fig, 6. LV, int. Iat.; Fig. 7. RV, int. Iat.; Fig. 8. RV, ext. Iat.
60
Wouters
Cretaceous and extant Iliffeoecia
three new species of Cardobairdia Bold, 1960 from the Cam panian of
Belgium and the Cenomanian of Southern England, ƒ. Micropalaeontol,
9(1), 65-70.
Pokorny, V.L., 1975, Revision of Bairdia septentrionalis (Ostracoda, Crust.)
from the Upper Cretaceous of the Netherlands. Acta Univ. Carol., Geol.
3, 237-248.
Pokorny, V.L., 1989. Pussella and Saipanetta (Ostracoda, Crustacea) in the
Lower Turonian of Bohemia, Czechoslovakia. Cas. Mineral. Geol,
34(3), 225-237.
Puri, H.S., 1974. Norm al pores and the phylogeny of Ostracoda.
Geoscience and Man, 6 , 137-151.
Witte, L., Lissenberg, Th. & Schuurman, H., 1992. Ostracods trom the
A lbian/ Cenomanian boundary in the Achterhoek area (eastern part
of the Netherlands). Scripta geol, 102,33-84,
Wouters, K., 1987. Comontocypris gen. nov., a m arine interstitial new
genus of the family Pontocyprididae (Crustacea: Ostracoda). Bull
Inst. r. Sc. nat. Belg, Biol, 57,163-169.
NOTE A D D ED IN PROOF
A fter subm ission of the m anuscript, the a u th o r noticed th a t the
genus Liasina G ram ann, 1963 (Geol. Jb., 82, 65-74), w ith type
species L. vestibulifera G ram ann, 1963, has to be considered a
senior synonym of Iliffeoecia M addocks, 1991. D etails on this sy n ­
onymy, together w ith considerations on palaeozoology a n d evo­
lutio n w ill b e p resen ted elsew here.
DISCUSSION
J.P.COLIN: l)W h a t is the lithology in w hich you found the
C retaceous "interstitial" ostracods?
2) The freshw ater interstitial ostracod Kovalevskiella m ig rated into
the interstitial e nvironm ent v ery recently. Fossil representatives
of N eogene age w ere definitely n o t interstitial a n d show no m or­
phological peculiarities. So w e h ave to b e careful in in terpreting
the m ode of life as interstitial w ith o u t taking into consideration
this possibility.
REPLY; 1) Iliffeoecia rectimarginata (N uyts, 1990) w as fo u n d in fine­
grained w hite chalk w ith dispersed m acrofossils.
2) The invasion of the interstitial e nvironm ent b y ostracods w as
probably not a single eevent, b u t m ay w ell h ave h a p p e n e d a t dif. ferent m om ents in tim e for different groups. It rem ains difficult,
how ever, to establish w h e th er a fossil lived interstitially.
Som etim es sm all size can be an indication.
62