The systematic potition and zoogeography of the Family Saididae Aranki et al. (Crustacea, Ostracoda) with the description of a new genus.

2007·3.1 MB·English

by  Wouters, K

BULLETIN DE L'INSTITUT ROYAL DES SCIENCES NATURELLES DE BELGIQUE BIOLOGIE, 77: 131-145,2007
BULLETIN VAN HET KONlNKLIJK BELGISCH INSTITUUT VOOR NATUURWETENSCHAPPEN B!OLOGIE, 77: 131-145, 2007
The systematic position and zoogeography of the Family Saididae ARANKI et al.
(Crustacea, Ostracoda), with the description of a new genus
by Karel WOUTERS
'I
Abstract monotypic subfamily Saidinae (raised to the rank of
family in the present paper). The discovery in the Indian
New material from the Indian Ocean yielded specimens with Ocean (Comoro Islands and Maldives) of specimens
preserved limbs of a species belonging to a new genus, closely with soft parts of Cytherura gushikamiensis NOHARA, a
related to the genus Sa ida HORNIBROOK, 1952. The new genus species redescribed in the present paper and placed in a
is described in the present paper. Both genera are discussed, and
new genus closely related to Sa ida, tlu·ows a new light on
the known species are listed. The subfamily SaidinaeARANKI et
the systematic position of the family Saididae.
a!., 1992 is raised to the rank of family. The systematic position
of the family Saididae is discussed and it can be concluded that
it is a family in its own right, with a mosaic of loxoconchid
SYSTEMATIC DESCRIPTIONS
and cytherurid characters. The (palaeo )zoogeographical
analysis shows that the family has a Tethyan distribution.
Class Ostracoda LATREILLE, 18 06
Key-words Order Podocopida SARS, 1866
Ostracoda, family Saididae, taxonomy, new genus, Superfamily Cytheroidea BAIRD, 1850
palaeozoogeography, Indian Ocean, Papua New Guinea.
Family Saididae ARANKI, MCKENZIE, REYMENT &
REYMENT, 1992
INTRODUCTION 1992 Subfamily Saidiinae ARANKI, MCKENZIE,
REYMENT & REYMENT, p. 8; originally described as
When describing the new genus Saida, HORNIBROOK subfamily of the family Cytheridae; raised to the rank of
(1953, p. 67) did not assign it to a particular family, family in the present paper.
but left it in "Family incertae sedis". Many subsequent
authors followed HORNIBROOK, by leaving the genus EMENDATION
Saida in familia incertae sedis, family uncertain etc.
It was GRONDEL (1969, p. 356) who for the first time The family name should be spelled Saididae instead of
attempted to place Saida in a broader taxonomic Saidiidae (originally described as subfamily Saidiinae by
framework, by assigning the genus, tentatively (i.e. with
ARANKI eta!., 1992). The stem of the genus name Sa ida
a question mark), to the family Cytheruridae, subfamily
is Said-. By adding the family suffix -idae, the family
Cytherurinae, tribe Orthonatocytherini (together with the
name becomes Saididae.
genera Orthonatocythere and Stillina). A few years later
McKENZIE (1974, p. 161) suggested that the systematic
TYPE GENUS
position of Saida may be with the Cytberinae, which
would associate it with Loxocythere. This point of view
Saida HORNIBROOK, 1952.
is shared by some later authors, such as NEALE ( 1975,
p. 13), WHATLEY & DOWNING (1983, p. 363), COLES DIAGNOSIS
& WHATLEY (1 989, p. 83) and WHATLEY et a/. (1993,
p. 353). In 1992, finally, ARANKI et a!. introduced the Oval to subrectangular small to medium-sized valves;
132 K. WOUTERS II
ventro-lateral arched carina, sometimes prominent; (1976, redescription of type specimen), ISHlZAKJ (1977,
valves punctate to nearly smooth; with or without caudal 1981), NOHARA & YABU (1983), WHATLEY & DOWNING
process; anterior and posterior submarginal denticles; ( 1983), RUAN & HAO (1989), YASSrNI & JONES (1995),
inner lamella wide; line of concrescence and inner margin TABUKI (2001). According to ZHOU (1995), S. torresi
coinciding; marginal pore canals few, rarely branching; HORNIBROOKs ensu RUAN & HAO ( 1989) does not belong
hinge lophodont to merodont. to this species, but is identical with their Sa ida sp.
Appendages (only known from Saidella gen. nov.):
Saida elliptica (BONNEMA, 1941 ); also mentioned by
antenna with one terminal claw; setation of mandibular
HOWE & LAURENCICH (1958), SZCZECHURA (1965) and
palp reduced; masticatory process with large distal hook;
HERRJG ( 1968).
maxillule with one short aberrant ray and with two endites
Saida pulchra Russo, 1964; also mentioned by Ascou
(one endite and palp absent).
( 1968), DALL 'ANTONIA et a/. (200 1, 2003 ).
GENERA ASSIGNED TO SAIDIDAE Sa ida nettgauensis GRONDEL, 1966, oldest record of the
genus (Lower Albian), also mentioned by WILKJNSON
Saida Hornibrook, 1952 and Saidella gen. nov. (1990).
Saida crassa HERRIG, 1968; also mentioned by HERRJG
RANGE (1966 and 1996, as Sa ida elliptica sensu HERRlG,partim),
by J0RGENSEN (1979) and by HERRJG (1993b).
Lower Albian -Recent.
Saida exilis HERRJG, 1968.
Saida media HERRIG, 1968.
Genus Saida HORNIBROOK, 1952
Sa ida rhomboidea NEALE, 1975.
TYPE-SPECIES Saida herrigi KEIJ, 1975; also mentioned by HANAI,
lKEYA & YAJIMA (1980), CAl & Tu (1983), NOHARA
Saida truncala (by original designation). According to & YABU (1983), NOHARA (1987), CAl (1991), TABUKI
SWANSON (pers. comrn. of HORNTBROOK to SWANSON, (2001).
in SWANSON, 1969, p. 47) and WHATLEY & DOWNING
Saida limbata COLALONGO & PASINI, 1980.
(1983, p. 363), Saida truncala HQRNIBROOK, 1952
Saida cuneata CIAMPO, 1983; also mentioned by
is a junior synonym of Cythere torresi BRADY, 1880
MICULAN ( 1992).
(= Saida). Morphological differences between Saida
species, however, are very small, and it is not exluded that Saida ovata CIAMPO, 1983.
both species are not synonymous after all. Fmther study
Saida recta CIAMPO, 1983.
of the type specimens is required to resolve this problem.
Saida ionica CIAMPO, 1988. Also mentioned by CLAMPO
Whatever the outcome, it does not affect the validity of
(1992) and DALL'ANTONIA (2002, 2003).
the genus Saida.
Saida micropunctata COLES & WHATLEY, 1989. HERRIG
DIAGNOSIS ( 1993a) emphasizes the strong similarity between this
species and Saida crassa HERRIG, 1968. Also mentioned
Small to medium-sized suboval valves with straight to by ZHAO (2005).
convex dorsal margin; valves without caudal process; Saida be!lsensis MCKENZIE, REYMENT & REYMENT,
valve smface punctate; ventro-lateral keel sometimes 1991.
forming a blunt wing-like expansion; hinge lophodont
Saida sissinghi ARANKI eta/., 1992.
to merodont; line of concrescence coinciding with inner
Saida daisa MCKENZIE, REYMENT & REYMENT,
margin; few radial pore canals, simple, rarely branched
1993. According to AYRESS (1995), this species has
(soft parts unknown).
to be considered a junior synonym of Saida limbata
COLALONGO & PASINI, 1980.
SPECIES ASSIGNED TO THE GENUS SAJDA.
Saida centra/is HERRIG eta!., 1997.
Saida truncala HORNJBROOK, 1952, the type species. Saida nudata HERRJG et al., 1997.
Also mentioned by HARTMANN, 1985.
Saida prasutegusi PYNE, WHATLEY & WILKrNSON,
Saida torresi (BRADY, 1880); also mentioned by 2003.
HORNIBROOK(l953), SWANSON (1969),PURI & HULINGS
II
Systematics and zoogeography of the Saididae (Ostracoda) 133
In open nomenclature Genus Saidella gen. nov.
Saida? sp. DELTEL, 1963; also mentioned by DUCASSE TYPE SPECIES
(1974, 1975, 1977), DUCASSE & CAHUZAC (1997) and by
CHAROLLAIS et a/. (1980). Cytherura gushikamiensis NOHARA, 1987 (here
designated).
Saida? sp. PIETRZENIUK, 1969 . .
Saida sp. ASCOLI, 1969.
DIAGNOSIS
Saida sp. SISSfNGH, 1972 (= S. sissinghi ARANKI eta!.,
1992). Very small subrectangular valves; dorsal margin
Saida sp. BABINOT eta!., 1987. slightly concave; prominent horizontal postero-dorsal
and vertical posterior ridge, ending in a postero-ventral
Saida sp. MCKENZIE, 1974.
spine; prominent arched lateral ridge running from
Saida sp. 2 DUCASSE & GREKOFF, 1976.
antero-ventral to postero-dorsal area; carapace laterally
Saida sp. Pokorny, 1981. compressed below this ridge; caudal process present;
Sa ida cf. S. nettgauensis GRONDEL, 1966; sensu WEAVER valve smface punctate to nearly smooth; hinge merodont;
(1982). inner lamella wide; line of concrescence and i1mer margin
coinciding; marginal pore canals few, postero-dorsal one
Saida sp. A CRONIN, 1983; also mentioned by COLES,
distinctly branched; muscle scar pattern consisting of four
AYRESS & WHATLEY (1990).
small adductor scars and a small subtriangular frontal
Saida WHATLEY, 1983.
scar.
Saida sp. MCKENZIE & PEYPOUQUET, 1984.
DERlV ATION OF NAME
Saida sp. Gou & CHEN, 1988.
• Loxoconcha sp. CARBONNEL, 1988; tentatively assigned
Saida and suffix -ella, meanmg little Saida; gender
here to Sa ida.
feminine.
Saida sp. GARCIA ZARRAGA & RODRIGUEZ LAZARO,
1990. SPECIES ASSIGNED TO SAJDELLA gen. nov.
Saida sp. AYRESS, 1993.
Cytherura gushikamiensis NOHARA, 1987, the type
Saida sp. ZHOU, 1995.
species.
Saida sp. 1 WHATLEY & BOOMER, 1995.
Saida nana HERRIG, 1968. Also mentioned by HERRIG
Saida sp. 2 WHATLEY & BOOMER, 1995.
(1996) as Saida elliptica (BONNEMA 1941) sensu
Saida sp. MAJORAN, 1996. HERRIG, 1968 partim, oldest record of the genus (Lower
Saida MAJORAN, 1997. Maastrichtian).
Saida sp. lRIZUKI eta!. 1998. Cytherura ldngmai BOLD, 1946, = Saida ? ldngmai
(BOLD), BOLD, 1988.
Sa ida sp. WHATLEY eta!., 1998.
Saida hobros RUAN & HAo, 1988.
Saida sp. WHATLEY & ROBERTS, 1999.
Cytherura nonspinosa AYRESS, 1996.
Saida sp. cf. S. recta C!AMPO, 1984 (DALL'ANTONIA et
a!., 2001). Saida sp. MCKENZIE, REYMENT & REYMENT, 1993 (=
Cytherura nonspinosa AYRESS, 1996).
Saida sp. 1 ArELLO & SZCZECHURA, 2004.
Cytherura cf. gushikamiensis AYRESS, 1993.
Saida sp. MAZZfNI, 2004.
Saida sp. BERGUE eta!., 2006.
RANGE
RANGE Lower Maastrichtian -Recent.
Lower Albian- Recent.
REMARKS
The new genus Saidella differs from Saida HORN !BROOK
'
''
134 K. WOUTERS
1952 by its subrectangular shape with a slightly concave DESCRIPTION
dorsal margin, the presence of a caudal process, a strongly
developed dorsal rib and a perpendicular posterior rib. Very small and subrectangulm· valves; dorsal and
ventral margin slightly concave and parallel; anterior
DISCUSSION margin broadly rounded; posterior margin with laterally
compressed caudal process, sih1ated at about 2/3 of the
See below. height; in loose valves the caudal· process is often worn
off; anterior and posterior cardinal angles present but
not prominent; anterior submm·ginal rib, with antetiorly
Saidella gushikamiensis (NOHARA, 1987) directed ve1y short ribs, forming about six a11terior
(Figs 1-~5; Plate 1, Figs I-9) denticles; postero-dorsal rib just below the dorsal
mm·gin; conspicuous, nem·ly straight and perpendiculm·
I987 Cytherura gushikamiensis NOHARA: 57, pl. 7, figs posterior rib ending in a large postero-ventral spine; weak
I a, I b. submarginal ventral rib; ventro-lateral carina extending
diagonally upwards in posterior direction, to the contact
point between postero-dorsal and posterior rib, but
TYPE LOCALITY
not reaching this point; ventro-lateral carina slightly
developed as a wing-like expansion. Below this cm·ina
S. Okinawa-jima (sample 75122802C ofNOHARA).
the valves are laterally compressed. Cm·apace punctate,
with exception of the ribs; punctations subcirculm· in the
TYPE HORIZON
anterior and antero-dorsal area or elongate nem· the lateral
carina and in the postero-ventral area. Inner lamella wide;
Chinen Sands, Pleistocene. The species is also mentioned
selvage vety distinct all around the right valve and along
from the Shinzoato Tuff, Upper Pliocene, Okinawa-jima.
the anterior and posterior margin in the left valve; seven
anterior marginal pore canals, the antero-ventral one
MATERlAL
divided; three posterior marginal pore canals; postero
dorsal one divided in two branches near the inner marain
One male specimen, with valves stqred d1y (O.C.1317a)
b '
each branch being divided again in two smaller branches
and dissected limbs preserved in a sealed glycerine
near the outer margin; muscle scar pattern consisting
preparation (O.C.1317b), from the Comoros, Grande
of four small adductor scars and a small subtriangular
Comore, Foumboni, collected at a depth of 14m, in coral
frontal scar; hinge merodont, with (in the right valve) an
sand. Leg.: Expedition Kmthala 81, Groupe Plongee,
anterior tooth divided in two toothlets, a smooth median
August 1st, 1981 (Station 6).
groove and a crenulate posterior tooth, consisting of
One male specimen, with valves stored illy
five toothlets; left valve with a nmTow accommodation
(O.C.l318a) and dissected limbs preserved in a sealed
groove.
glycerine preparation (O.C.l318b) from the Republic
Antennule: slender, six-segmented; setation reduced;
of Maldives, South Male Atoll, Villi Varu Island, depth
third segment with one, and fifth segment with two dorsa
I m, in sand. Leg.: F. FIERS, December 3rd, 1984 (station
distal setae; terminal segment with two long setae.
84/66).
Antenna: fom-segmented; one ventro-distal seta on
One left and one right valve (O.C. 1319) from N.
second segment; sh·ongly developed, two-segmented
Papua New Guinea, Madang Province, Megiar Harbom,
exopodite; third segment consisting of fusion of two
I45° 46' 04" E, 4° 48' 57" S, coral sand from shallow
segments, bearing three setae, a ventral and dorsal median
tidal pool. Leg.: J. VAN GOETHEM, July 21st, I981
one, and a ventro-distal one; terminal segment short,
(station 81/496).
bearing only one strong claw.
One left valve (O.C.l319bis) from N. Papua New
Mandible: palp four-segmented; first segment without
Guinea, Madang Province, Malagere Island, 144° 56' 33"
setae; epipodite not seen, probably absent; second segment
E, 4° 13' 46" S, coral sand, depth 3m. Leg.: J. PIERRET,
with one venh·o-distal seta implanted on a distal semi
June 1Oth, 1979 (station 79/292).
oval widening of the second segment; third segment with
The studied material is deposited in the ostracod
four setae: a dorso-proximal one, a dorso-distal one and
collection of the Royal Belgian Institute of Nahtral
two .ventro-distal setae; terminal segment subquadrate,
Sciences, Brussels (Belgium).
beanng tlu·ee short curved setae; masticatory process
with irregular molar teeth; dorso-distal seta developed
I I
Systematics and zoogeography of the Saididae (Ostracoda) 135
as a large claw-like hook, connected with a joint to the between genetic and family characters.
process.
Maxillule: one short aberrant ray; 15 or 16 nmmal SYSTEMATIC POS!TlON OF THE FAMLLY SAIDIDAE
rays; only two endites present, bearing respectively three
and four curved short claw-like setae; palp and one endite ARANKI eta!. ( 1992) described the Saidinae as a subfamily
absent. of the Cytheridae. It was MCKENZIE (1974, p. 161) who
First leg: with four segments; first segment with one suggested for the first time that the systematic position of
ventral and 1+ 1+ 2 dorsal setae; second segment with Sa ida may be with the Cytherinae, which would associate
one antero-distal seta; third and fourth segments without it with Loxocythere. This point of view is shared by some
setae; fourth segment with one stout, curved claw. later authors, such as NEALE (1975, p. 13), WHATLEY &
Second leg: first segment slightly longer, with 1 DOWNING (1983, p. 363), COLES & WHATLEY (1989, p.
ventral and 1+ 1+ 1 dorsal setae; second segment with one 83), and WHATLEY et al. (1993, p. 353). In the present
antero-distal seta. paper, however, the subfamily Saidinae is raised to the
Third leg: large first segment with 1+ 1 dorsal setae; level of family, with a somewhat different position.
second segment long, with one antero-distal seta; fowih When comparing the characters of the valves and limbs
segment with obliquely insetied, cmved terminal claw. of Saida and Saidella with those of members of other
Brush-like organ present, with medium-sized shaft and families, it can be concluded that the family Saididae
relatively short hairs. shows relationships as well with Loxoconchidae as with
Copulatory appendage vety small, with a sub Cyheruridae. Both families are closely related, as shown
rectangular basal part, two lobe-like distal expansions by ELOFSON (1941, p. 305) and HARTMANN (1964, p.
and a strongly chitinized club-like process. 63-65). The limbs of Saidella are reminiscent of those of
Abdominal extremity with an elongate triangular the Loxoconchidae. The middle segment of the antenna
blade-like prolongation, dorsally set with fine setules. is divided in Cytherura and Cytheropteron and undivided
Dimensions: length 0.243-0.253 mm; height 0.132- in Loxoconcha and Saidella. The number of setae on
0.141 mm. the proximal endopodite segment of the antenna is 2
Specimens ofNOHARA ( 1987, p. 58) are somewhat larger: in Cytherura and Cytheropteron, and 1 in Loxoconcha
length 0.27-0.29 mm; height 0.15-0.17 mm. and Saidella. The number of aberrant "Strahlen" on the
respiratory plate of the maxilulle is 2 in Cytherura and
Cytheropteron and 1 in Loxoconcha and Saidella. The
Discussion
number of dorsal setae on the protopodite of the legs is 1,
2, 0 in Cytherura and Cytheropteron, and 2, 1(2), 1(2) in
ANEW GENUS
Loxoconcha and 2, 2, 1 in Saidella.
The valve characteristics of Saidella, on the other
In his review paper on the genus Sa ida in the Cretaceous,
hand, are closer to the cytherurids because of the broad
HERRJG (1968) already foreshadowed the possibility of a
inner lamella, the number and nature of the marginal
new genus, by dividing the genus into three groups. His
pore canals, and the merodont hinge (loxoconchids have
group 3, with Saida nana HERRIG, 1968, corresponds
with the here described new genus Saidella. a gongylodont hing~). Some cytherurid species show
a remarkable resemblance to the valves of Saidella,
As far as the valves are concerned, the new genus
such as Semicytherura pulchra (for description, see
Saidella can be easily distinguished from Saida by its
AYRESS & CORREGE, 1992, p. 57), by the presence of a
subrectangular shape with a slightly concave dorsal
caudal process, a horizontal postero-dorsal and vertical
margin, the presence of a caudal process, a strongly
posterior ridge, an anterior and ventro-lateral ridge and
developed dorsal rib and a perpendicular posterior rib.
anterior marginal denticles. The valves of Saida-species
The appendages show a unique set of features: reduced
are somewhat different from those of Saidella-species,
setation on antetmule (fig. 3), antenna (fig. 4) and
and look in some instances like ins tars of Ioxoconchids.
mandibular palp (figs 8 and 9), only two endites (instead
It is not to be excluded that in the loxoconchid
of three) and absence of palp on the maxillule (figs 5 and
cytherurid family-complex, heterochrony played a
6), and a large dorsa-distal hook (figs 7 and 9). Some of
role in the evolution of the family characters of the
these characteristics, such as the reduction of setation, the
Saididae. Unfortunately, the limbs of the genus Saida
absence of one endite and the palp of the maxillule and
remain unknown. It can be concluded that the family
the small dimensions of the valves may be adaptations
Saididae is a family in its own right, with a mosaic of
to an interstitial way of life. Because the soft parts of the
loxoconchid and cytherurid characters.
genus Saida are unknown, it is difficult to distinguish
I'
136 K. WOUTERS
_______ ,,:I
.............. .,
5
50 iJm
10
Figs 1-8. Saidella gushikamiensis (NOHARA, 1987). I. Right valve, internal view. 2. Left valve internal view. 3. Antennule. 4.
Antenna. 5. Maxillule. 6. Maxillule. 7. Mandible. 8. Mandibular palp. Figs 1-4 and 6: Foumboni, Grande Comore,
Comoros (O.C. 1317). Figs 7-8: Villi Varu, South Male Atol, Maldives (O.C. 1318).
''
Systematics and zoogeography ofthe Saididae (Ostracoda) 137
~
13
t------ 30 !Jm --i
14
Figs 9-15. Saidella gushikamiensis (NOHARA, 1987). 9. Mandible. 10. First leg. II. Second leg. 12. Third leg. 13. Abdominal
extremity. 14. Brush-like organ. 15. Copulatmy appendage. Figs 9-11 and 13-15: Foumboni, Grande Comore,
Comoros (O.C. 1317). Fig. 12: Villi Yaru, South Male Atol, Maldives (O.C. 1318).
,,
138 K. WOUTERS
Plate I. Saidella gushikamiensis (NOHARA, 1987). Fig. I. Left valve external view, male, Comoros (O.C. 1317). Fig. 2. Left valve
internal view, male, Comoros (O.C. 13 17). Fig. 3. Right valve external view, male, Maldives (O.C. 1318). Fig. 4. Right
valve internal view, male, Maldives (O.C. 13 18). Figs 5-6. Hinge right valve, male, Maldives (O.C. 1318). Figs 7-8. Hinge
left valve, male, Comoros (O.C. 1317). Fig. 9. Right valve, external view, Papua New Guinea (O.C. 1319).
II
Systematics and zoogeography of the Saididae (Ostracoda) 139
Zoogeography of the family Saididae fauna (KAUFMANN, 1973). The family Saididae, with
the genera Saida and Saidella, can therefore be called
Figs 16-19 illustrate the known distribution of fossil and a Tethyan family, which may have originated along
Recent Sa ida-species, and fig. 20 of Saidella-species. the northern Tethyan margin and dispersed slowly.
The oldest known species of the genus Saida, MCKENZIE (1973) already stressed the impat1ance of
S. nettgauensis GRONDEL, 1966, was found in lower Tethys for the distribution of ostracod? in general, and of
Albian deposits in borehole Nettgau, Saxony, north Saida-species in particular.
central Germany. Most other Cretaceous localities are There are remarkable similarities between the origin
situtated in Europe. There is one record of the genus, and distribution of Saida/Saidella and Microceratina
however, in Australia, namely Sa ida rhomboidea NEALE, (see NAMIOTKO eta!. 2004). The three genera have their
1975 from the Santonian chalk of Gingin (W. Australia). oldest record in the Cretaceous of the North European
In Post-Mesozoic times the genus is spreading slowly to Province of Tethys, where they probably originated,
the Indian and Pacific Oceans, and later to the Atlantic. and from where they dispersed over different parts of
The genus Saidella is much younger. The oldest known the world. Fm1hermore, species of these genera are
species of the genus was found in the lower Maastrichtian rare. This means that in a single locality the number of
of the Isle of Riigen (N. Gennany). Post-Cretaceous individuals per species is always very low, throughout
occurrences are sporadic in Paleogene and Neogene geological time, but also that the number of localities
deposits, and only four Recent localities are known. The where species of the three genera occur is low. This
species of the genus Saidella probably descended from means rarity in two senses, namely rarity of individuals
a Sai da-ancestor, and given the small dimensions of the within areas (density rarity), and the condition of
valves, and the partial reduction of the limbs, most likely occurring infrequently (range-size rarity). Finally, it
adapted to interstitial life. remains puzzling to see that some ancient low diversity
Both genera, Saida and Saidella, have their oldest lineages survived over so long periods of time, e.g.
· record in the Cretaceous, in the Nat1h European Microceratina (NAMIOTKO et al. 2004), Liasina
Province. This province, belonging to the Temperate (WOUTERS, 1996, 1998), and now Saidella and to a
Realm, was close to the boundary of the Tethyan Realm lesser extent Sa ida.
and predominantly comprised warm to mid-temperate
Fig. 16. Distribution of the genus Saida in the Cretaceous.
I I
140 K. WOUTERS
Fig. 17. Distribution of the genus Saida in the Paleogene.
Fig. 18. Distribution of the genus Sa ida in the Neogene.