OSTRACODS FROM THE PECTEN CONGLOMERATE(PLIOCENE) OF COCKBURN ISLAND,

ANTARCTIC PENINSULA

JANIN A SZCZECHU RA and JAN USZ BLASZYK

Szczcc hura, J. and Blaszyk, J. 1996. Os tracods from the Pecten Co ng lomera te (Pliocene)of Cockburn Island . Antarc tic Peninsul a. 111 : A. Gazdzicki (ed .) Palaeont ological Result sof the Pol ish Antarctic Expeditions. Part 11. - Palaeont ologiu Polonica SS. 175-1 86.

Sixtee n spec ies of Ostruc oda, belon g ing to 15 ge nera and 8 families . representing Pod o­co pina only. are described from the Pliocene Pecten Co nglome rate o f Cockburn Island.A nta rctic Pen insul a. Fo ur spec ies are referred to still living spec ies. four are rega rded asclose to those inh ab iting Antarctic waters and the so uth-we st Atlant ic today. while therem ainder app ear to be e ndemic. The faun a sugges ts an enviro nmen t similar to thatpresentl y ex isting in Antarctica . So me of the ge ne ra i.e . Patagotutcvth ere and Australicv­there, described here for the first tim e from the Pliocene of the Southern Hemi sphe re. areknown from the Plio-Pl e istocen e of the Northern Hemi sphe re. Th ey indi cate bip olar d is­tribut ion of the os traco d faunas in the Pliocene.

K e y w o r d s : Os traco da , taxon omy. paleobiogeograph y. paleoecology , Pliocene, A n­tarct ica.

Janina Szczechura. lnstvtut Paleobiologii PAN. A/eja ZH'irki i Wigllrv 93. 02- 089 WarSZlIl l'll.Poland.Jal1l1SZ Blastvk, 111 .1'/.1'/111 Paleobi ologii PAN, A/eja ZH'irki i Wigllry 93. 02-089 WarSZllll'll,Poland.

Received 7 July 1995. accepted IX October 1')') 5

176 JANINA SZCZEC HURA and JANUSZ BLASZYK

CONTENTS

Introdu ction

Acknow ledge ments

Materi al .

Geo logica l and stra tigrap hica l setting

Paleob iogeograph y . . .

Paleoecology .

Sys tematic paleontology

Fam ily Cy theridae Bi\IRD, I X50

Genus Loxocythere HORNI BROOK, 1953

Family Neocytherideididae PURl, 1957

Ge nus Copytus SKOGSBERG, 1939 .

Family Lept ocytheridae Hi\Ni\I, 1957

Ge nus Lept ocyth ere Si\RS, 1925 ..

Family Trachyleberidid ae SYLVESTER- BRi\DI.EY, 1948

Ge nus Pseudocyth ereis S KOG SBERG , 192X

Family Hemicytheridae PURl , 1953

Ge nus Rab ilimis Hi\ZEL, 1967 .

Genus Procythereis SK()(;SBERG, 192X

Ge nus Alistralicy there BENSON, 1964

Genus Patagonacyth ere Hi\RTMi\NN, 1962

Ge nus Meridiona licyt herc WHi\TLEY, C1 1i\ DWICK , COXII .L et ToY, 19X7

Family Loxoconchidae Si\RS, 1925 .

Genus Antarctiloxoconcha Hi\RTMi\NN, 19X6

Fami ly Cytheruridae G.W. MULLER , IX94

Ge nus Semicythe rura Wi\GN ER, 1957

Gen us Hemicyth eru ra EI.OI'SON, 194 1

Genus Cytheropteron Si\RS. 1X66 . .

Genus Loxoreticulatum BENSON. 1964

Family unknown .

Ge n. et sp. incert.

References .. . . . .

INTRODUCTION

176

177

178

178

179

180

I XO

I XO

I XO

I XO

I XO

I XI

I XI

I XI

I XI

181

I XI

I XI

I X2

I X2

I X3

I X3

I X3

I X3

I X3

I X3

I X4

I X4

I X4

I X4

I X4

Becau se there is no earlie r publ ished acc ount o f Neogene Antarct ic os tracods, we felt it imp ort ant topublish thi s rare fauna, despite its poor preservatio n. Th e mat er ial comprises two os tracod co llec tionsfro m the Pl iocene Pecten Co ng lo merate of Cockburn Island, off the Antarct ic Peninsul a (Tex t-fig . I). Oneof the co llec t ions (numbered ZPAL O.XXXV lI/I - 19) and hou sed in the Inst itute of Paleob iol ogy of thePoli sh Acade my of Sc iences in Warszawa, was co llected by Andrzej GAZDZICK I, du ring the Arge ntine­- Polish Anta rctic Exped itio n to Seym our (Ma ra mbio) Island in the 1987-1 988 aus tra l summe r. Th e secondco llection (numbered AI' 54414-54435 ) and deposit ed in the Natu rhi storiska Rik smuscet in Stockho lmwas taken during the Swedish So uth Pol ar Ex ped ition (1901- I903) led by Ott o NORDENSKJOL D. Th eSwedish co llection was to so me ex tent elabora ted by G.W. M OI.LER (see HENNIG 1910, p. 10).

BLASZYK ( 1987) described an os traco d assemblage from the so-called "Pecten Con glom erate" i.e. theLow Head Member of the Polon ez Cove Format ion on Kin g George Island, South She tland Islands

OSTRACO DS FROM THE Pf.'CTE..'N CONGLOMERATE 177

Vega I.

James Ross I.

Weddell Sea

70 "S

Cockbum Island

QOL;2mourI.

(),

oSnow Hill I.

Fig. ILocat ion map for Jam es Ross Island area, Antarctic Pen insul a. Cockburn Islan d arrowed .

(BIRKE Nt\lAJER 1982), attributed to Pli ocen e (BARTON 19 65 ) and lat er correcte d to be o f Oligocen e age(GAZDZICKA and GAZDZICKI 1985 ; BIRKENMAJ ER a nd GAZDZICK I 1986).

Th e pect inid-bearing con gl omerate from King George Isl and does not corre la te w ith th e PectenCong lo merate o f Coc kburn Isl and , w hic h is rega rded as Pli oc ene in age (BIRKEN MAJER et al . 1991 ;GAZDZICK I and WEBB 1996 thi s vo lume), The ostracod asse m blages fr om these two local ites a re qu itediffer ent in th eir taxo no mica l compos itio n; one spec ies is (te nta tive ly) referre d to a genus com monbetween the ostracod assem blages from the Pecten Cong lomera tes o f the Cockburn Isl and and th e Pol onezCove Fo rmation o f King George Isl and. T he ge nus Cytherop tcron, fo und in th e compare d ostracodasse m blages, is represented by various s pe c ies .

Acknowledgements . - T he a uthors are deepl y grateful to Or. A ndrzej GAZDZICK I (In stitute of Paleo­biol ogy, Poli sh Acade my o f Sc iences , Warsza wa) for s upply ing mat eri al a nd geolog ica l info rm ati on , aswe ll as the cha pter w ritte n by him on the geology of Cockburn Isl and ; to Or. Elisabe th M . BROUWERS(U.S . Geolog ica l S urvey, Den ver Fe deral Ce nte r, Den ver, U .S .A .), Prof. Or. Gerd H ARTM ANN (Zoo log i­sc hes Insti tut und Zoologisc hes Museum, Hamburg ), Dr. Qadder S IDD IQLJ I (Saint M ary ' s Uni versity,Halifax. C ana da) . Prof. Or. Robin WHATLEY (In sti tut e o f Ea rth Scie nces, U nivers ity College o f Wal es,A berystwyt h, U. K.) a nd O r. T ho mas M , CRONIN (U .S . Geolog ica l S urvey, Reston , Virg inia) fo r the irco m ments on th e determination of the ostracods describ ed here . The autho rs are particul arl y th ankful toProf. Or. Robin W IIATLEY for reading th e tex t as we ll as impro vin g th e Eng lish lan gu age , The technicalhel p was offere d by Mi ss Ewa HARA and Mi ss Danuta KOSCIELSKA (bo th fro m the Institute of Paleob iol o­gy, Poli sh Acade my of Sci en ces . Warszawa). One o f us (1B) is ve ry th ankful to Pro fessors Valda rJAANLJSSON and Jan BERGSTR() M (Naturhis to riska R iksmuseet , Stoc kho lm) for allowi ng exam ina tion and

178 JAN INA SZCZECHURA and JANUSZ BLASZYK

elaboration of the material co llec ted by the 1901-03 Swedi sh So uth Polar Ex peditio n. SE M photographswere taken at the Electron Microscopy Laboratory of the Institute of Paleobi ology of the Polish Academyof Sciences, Warszawa.

MATERIAL

The ostracods co llec ted by A. GAZDZICKI during the Argentine- Polis h Antarctic Expedition ( 1987-88)co nsist of 19 spec imens, including carapaces and va lves of adult and j uve niles . In many cases these arebadly preserved , i.e. crus hed and encrus ted with seconda ry mineral isat ion . In co ntras t to the co-occuringbenthic fo raminifera (see GAZDZICKI and WEBB 1996 this vo lume), ostracods are very rare.

Wh ile the os tracods co llec ted by the 1901-03 Swed ish So uth Polar Exped ition are better preservedthan those in our co llec tion, they are rather less diverse. In the orig ina l Swedi sh co llec tion there are 30spec ime ns, including ca rapaces and valves of adult and ju ven ile forms. G.W. MULLER, as mentioned byHENNI G ( 1910) , recogni zed within th is co llection: Cythereis speyeri BRADY , Cythere is sp. gr. margaritiferaBRADY, Cythereis sp. gr. convexa BAI RD, and Cytheropteron or Loxoconcha.

GEOLOGICAL AND STRATIGRAPHICAL SETTING

Cockburn Island lies in the north western Weddell Sea at the northern end of the Anta rctic Peninsul a,some 8 km fro m Sey mo ur Island (Text-figs 1- 2).

Cre taceous and Tert iary strata and basalt flows are exposed on Cockburn Island . Foss il-bea ring sha llowmarine successions of the Upper Cretaceous Lopez de Bertodano and the Eocene La Meseta Formationsare ex posed in the lower slopes of the island (AsKIN et al. 1991 ; BARNES and RIDI NG 1994).

Fig . 2 .Cockbum Island viewed from the L6pez de Bertod ano Bay. Seymour Island . Arrow shows the Pecten Co ng lome ra te

co llecting si te. Photograph taken by A. Ga ZIJZICKl, January 1988.

OSTRACODS FROM T HE PECTEN CONGLOMERATE 179

During th e Arge nt ine- Po lish A nta rc tic Ex pe ditio n in the au stral su mme r o f 1987-1 988, A nd rzejGAZOZ ICK I vis ited Cock bu rn Isl and. The pu rp ose of th is visi t was to loc at e ill si tu outc ro ps o f the PectenCong lo me ra te and to sa mple for micropaleontol ogical and geochem ica l stud ies (see DOKTOR et a l. 1988).

The Pecten Cong lomerate is pr eserved on an erosiona l ho rizontal ben ch in th e Pl iocen e basalt s locatedapproxi ma te ly 250 m above sea level (Tex t-fig. 2, see also ANDERSSON 190 6 ; Z INS ME ISTER and WEBB1982 ; GAZDZICKA and GAZDZICKI 1994 ; GAZDZICK I and W EBB 1996 thi s vo lume) . The cong lomerateco ns is ts of poorl y sorted co ng lo meratic and gravely sands to nes . The c las ts in the cong lomerate are mostl ybasalti c in compositio n. The name of the unit is tak en fro m the bi val ve Chlamys andersson i (HENN IG,1910) whic h occurs in ab unda nce at th e type locality.

T he K/AI' rad iome tr ic data obta ine d fro m th e basalts whic h underli e the Pecten Cong lo me ra te (WEBBand ANDREASEN 19 86 ; R.A . KELLER person al co m munica tio n, 1992 ) as we ll as th e stud ies of d iatoms(HARWOOD 1986) and benthic fo ra minife ra (GAZDZICK I and W EBB 1996 thi s vo lume) recogni zed in theco ng lomerate, poi nt to a lat e PIiocene age.

The ric h and diverse b iota of th e Pecten Cong lomerate indi cat e in te rg lac ia l co nd it io ns during thede pos itio n of this sequence (GAZOZICK I and WEBB 1996 th is vo lume) .

PALEOBIOGEOGRAPHY

O f the six teen ostrucod species recognized in the st udied sa mples. fou r: Copytus ca lig ula SKOGSBERG,1939 ; Pseudocythereis spinijera SKOGSBERG. 1928 ; Australicythere polyl vca (G.W. M ULLER, 1908) andAnta rcti loxoconcha [rigida (NEALE, 1967 ), s ti11 inha bit Anta rct ic wa ters to day and are rest rict ed to tha tarea; fo ur spec ies: Procythere is cf. robusta SKOGSBERG. 1928; Patagona cythere cf. longiducta (SKOGS­BERG, 1928 ), Putagonacythere cf. tricostata HARTMANN, 1962 and Hemicytheru ra cf . reticulata HART­MANN. 1962, are regarded as c lose to those sti ll living in A ntarctica or the so ut heastern At lantic, whilethe remainder seem to be endemic. T hese species be lo ng to the cosmopo litan genera Leptocythere,Semicytherura or Hemicyth crura , or to ge nera rest ricted to the Southern Hemisph ere ; i.e . 'Il.oxo cyt here,?Meridionalicy /here. Autarcti loxoconcha and ?Loxoreticula tum .

T here are , however. a lso representatives of Australicyth ere, i.e . A . polyl vca (G.W. M ULLER, 1908).Patagonacythere, i.e. Patagonocythcre cf. long iducta (SKOCiSBERG, 19 28) and Patagonacytli ere cf. tricos­tata I-L\RTM ANN. 1962) as we ll as ?Rabilintis. i.e . ?Rabilimis sp. A mong these forms the representati vesof Patagonacythere and Australicytliere seem to be part ic ularly im portant as biogeograph ica l indicato rs ;tentative ly determ ined Rabilimis appea r to be a do ubtful pa leobiogeographical mar ke r and it is notemployed here .

The genus Austra licythere occurs in the Eocene and Upper O ligocene-Lower Miocene of Argent ina ,in th e Miocene deposits of so uthern Brazi l (see KELBOW ICZ 19 88) and in the Pliocen e of Ice la nd, whilePata gonacythcre is recorded in the O ligocene of so ut he rn Argen tina (E CIIEVARR IA 1991 ), the lat e Mi ocen e(IRIZlIKI 1994) as we ll as the Plio -Pleis toce ne of Japan (CRONIN and IKEYA 1987). KELBOWICZ ( 1988) alsome ntioned records of Copy/us in the Upper O ligoccne-Lower M ioccn e depos its of southe rn Argentina(A ustra l Basin) and the Lower M iocene of so uthern C hile, whi le BLASZYK ( 1987) descri bed Copytus fro mthe O ligocenc Pol on ez Cove Formatio n of King George Isl an d (South She tland Islands).

A ll these latter records suggest that migrat ion ro utes of th e late Neogene os tracods co uld havesi multaneous ly fo llowed At lant ic as we ll as the ludo-Pac ific pathways. They may also suggest thatostracods typical of the Pli occn e and presen t-day env ironme nts of th e Anta rctica (most ly the c irc um-Ant­arctic she lf) appeared much ea rl ier i.e. in the late Pa leogene in the southern Atlantic. COLES et a l. ( 1990)ind icated, that there were numerous Cainozoic dee p-sea ost racod s pecies co m mo n bet ween the NorthAt lantic an d the Paci fic ; these common genera. according to these authors, appeared in the Eocene of theNorth At la nt ic . T he above ment io ned record s arg ue. moreover, for the di rect bipol ar excha nge of at leastsome os tracod taxa (especia lly the deeper water ones) via Atla nt ic, fo llowi ng o ld, mar ine path ways kn ownat least s ince Eocene . COLl:S et al . ( 1990) proposed the Dr ak e Passage for the Neogen e interchan ge o fostracods between the Atla ntic and Pac ific . SZCZEClI lJRA ( 1994, 1995) sugges ted th e Middl e M ioceneexcha nge of the Ind o-Pac ific and No rth Atla ntic deep-water os tracod faunas via so uthe rn Atlantic , exclud­ing the Te thys as a ro ute.

180 JANINA SZCZECHURA and JANUSZ BLASZYK

PALEOECOLOGY

A na lys is o f th e envi ro nmenta l par am et ers , mostl y the de pth and the wa te r te mperatures preferred byRecent members of so me of th e os tracod spec ies ident ified , perm it the recon struct ion of th e env iro nmenta lparam eters o f the Pli oc en e os tracod assemblage from Coc kburn Isl and. Recent representa tives o f Copytuscaligula, Pseudocyth ereis spinifera , Aust ralicyt here polvlyca and Antarctiloxoconcha [rigida live o n theAntarctic she lI' at depths bet ween 60-200 m and te m perature less th an 2e

C (HARTM ANN 1986, 1990).Pata gonacythere and Loxoreticulatum inc lude spec ies inh abiting the she lf areas, inc ludi ng tod ay' s Ant­arct ic she lf (BENSON 1964; HARTMANN 1986, 1990). Hemicytheru ra as we ll as Sem icytheru ra and Cyt he­roptero n include spec ies o f wide temperature and bath ymet rical ran ges ; Cytheropteron, howe ver, is knownto prefer deeper waters. S imilar e nvironme nta l co ndi tio ns i.e. clo se to th ose ex isti ng no w in th e A nta rc tico ute r she lf, we re probabl y cha rac terist ic of the Pliocen e os tracods from Coc kburn Island (see a lsoGAZDZICKI and W EB B 1996 thi s vo lume) . KELBOWI CZ ( 1987), working on the ea rly Neogen e mi crofaunaof Argentina (A us tra l Basin), sta te d co ld wa te r e nv iro nment o f th e os tracod assem blage contai ning, am on gothe rs, Australicythere and Copytus.

The above proposition , conce rn ing the pa leoenv ironme nt (mos tly depth ) of the stud ied os tracods,seems to be supported by the rather lar ge di versity o f th e stud ied os tracods .

SYSTEMATIC PALEONTOLOGY

The fo llowing abbrev iatio ns are e mployed: a - ad ult, j - j uve nile, C - carapace, RV - right va lve ,LV - left va lve .

Fa m ily Cytheridae BAI RD, 1850Ge nus Loxo cythere HORNIB ROOK, 1953

TLoxocythe re s p.(P I. 40 : 3-5)

Material. - O ne j LV from the Poli sh co llect io n, two aRV fro m the Swed ish collect io n .Remarks. - In co mpa rison with publ ished Loxocythere , especia lly the Recent Loxocytli ere king i

HOR NIBROOK, 1953, from New Zealand, th e Pecten Cong lome ra te (Pliocene) form is more trian gular inlateral out line and lacks th e lat e ro ventral in tl atio n overha ngi ng the ve ntra l margin . It seems also to bemore concentrically pitted and deli catel y ri bbe d a lo ng the margins bo th post e riorly and anteriorly. Int er­nall y, th e Pli ocen e form has rath er narrow duplicature alon g the e nt ire free ma rg in .

Distribution . - Pecten Cong lome rate (Pliocene) fro m Cockburn Isl an d.

Fa m ily Neocytherideididae P URl, 1957Genus Copytus SKOGSBERCJ , 1939

Copytus ca ligula SKOG SBERG, 1939(PI. 39: I )

1939. COPY/liS caligu la SK O(; SBERG new species: SK OGSBER(; . p. 4 15. text- figs 1-1 3.

19R6. COPY/liS caligula S KO( ;SBERG . 1939: H i\ RT Mi\ NN. p. 156. te x t-fi g . 17. pI. I : 1-4.

1990 . COPY/liS caligula SK()(;SBERG . 1939: H i\ RT Mi\ NN, p. 203.

Material. - O ne aC fro m th e Swedis h collec tio n.

Remarks. - The ex te rna l fe atures o f thi s fo rm seem not to differ from th ose o f livin g representati veso f the species . In th e Pli ocen e spe c ime n, ho we ver, in the right valve , there a re 2-3 weak anterovent ra lrib s . In comparison w ith Copyt us elongatus BENso N, 1964 , a Recent s pec ies described from the A ntarc tica ,fo und th e re a lso by N EAtE ( 1967) and H ARTM ANN ( 1986, 1990), it is on ly slig htly less e longated.

Distribution . - Pecten Con glomerate (Plioccnc) fro m Cockburn Isl and ; Rec ent o f A nta rc tica, i.e.South Georgi a (SKOGSBERG 1939), Elepha nt Isl and (HARTMA NN 1986), and th e Antarc tic Peninsula regi on(HARTMANN 1990); it a lso occurs alon g the so uthe rn coast o f Brazil at depth o f at so me 250 m (R. WH ATLEYperson al co m mu nica tio n, 1995).

OSTRACODS FROM T HE PECTEN CONGLO ME RATE

Family Leptocytheridae HANAI , 1957Genus Lept ocythere SARS, 1925

?Leptocyt here sp.(P I. 40: 1- 2)

ISI

Material. - Tw o ?aC from the Poli sh colle ctio n.

Remarks. - Ex te rna l appe ara nce of s pe c imens resembles l.ep tocythere. Int ernal features o bscured.Cara paces e lo ngated , with nearl y parall el dorsal and ventral margins, di stinctly ro unde d anterior marginand rather a bruptly truncat ed poste rior margin . They are weakly and almo st evenly infl ated with atubercl e-like infl ati on in the ante rodo rsa l par t. Th e cara pace surface is regul arl y a nd den sel y pitted andcovered by tin y rib s a long th e ante rior, ve ntra l and posterio r margins. The free margin is bordered by arim , best devel oped post e rod orsall y. In com parison with speci me ns of Lept ocythere patagonica H ART­MANN, 1962, a Recent spec ies desc rib ed by HARTM ANN ( 1962) fro m C hile , the M agell an S tra it andArgent ina, an d tho se described by WII ATLEY and M OGUILEVSKY ( 1975) from A rge ntina , it has a moredi stinct anterodorsal infla tio n and a deep su lcus . WII ATLEY et al . ( 1995) placed Lept ocythere pa tagoni caHARTM ANN in the sy no ny my of L. mosleyi (BRADY, 1880)

Distribution. - Pecten Cong lo merate (Pliocene) from Cockburn Island .

Fa mi ly Trachyleberididae SYLVESTER- BRADLEY, 1948Genus Pseudocyth ereis SKO(iSBERG, 1928

Pseudocyth ereis sp inijera S KOGSBERG, 1928(PI. 41 : 1- 2)

1928. Pseudocvth creis spinifera SK()(;SBI'R(; ne w species; p. 130. tex t- fi g . 22: 1- 5.

1990 . Pscudocyth ereis spi uife ra SK()(;SBI'R( ; . 1928; H ;\ RT M ;\ NN. p. 203. pI. I: 7.

Material. Two aC and o ne aLV from the Swedish collectio n .

Remarks. - Th e ad ult s pec ime ns re ferred to the spec ies vary somew ha t in the details of th eir or­namentati on i.e. sha pe and a rra ngement of reti culae (meshes. fossae), and, at the sa me time, and to th esa me ex te n t, they d iffer a little from spec imens of Pseu docythereis spinifera SKOGS BERG, 1928, es peciallyas illustrated by HARTl\lANN ( 1990 ).

Distribution. - Pecten Cong lo mera te (Pliocenc) fro m Cockburn Isl and. Pseudocyth ereis sp inifera,described by SKOGSBERG ( 1928) as Recent form fro m the so ut he rn Atla ntic, was a lso found by HARTMANN( 1986. 1990) in the South S he tland Isl ands as we ll as the Antarct ic Peninsula area .

Fa m ily Hemicytheridae PURl, 1953Gen us Rabilimis HAZEL, 1967

TRabilimis s p. (PI. 42: 1- 7)

Material. - Fo ur aC and one aLV fro m the Swedish co llec tion, and o ne aC and one LV fro m thePol ish collect io n.

Remarks. - S peci mens seem to be somewha t s imi la r to those referred to Rabilimis paramirabilis.Pli o-Ple istocen e spe ci me ns o f thi s latter species were described by SWA IN ( 1963) and BROUWERS andM ARCINOVI CII ( 1987) from A las ka, and from the Pli o-Plei stocen e o f the Easte rn Beaufort Sea by S IDD IQUI(1988). In compa rison with th is latt er spec ies, the Pli oc en e fo rm from A ntarc tica is , at firs t, less tri an gula rin its lat eral out line, ge nera lly has a less di stinct anterior ca rd ina l ang le, and is reti culated on th e entireva lve s urface with e lements o f o rna me ntatio n in th e lat ero ventral pa rt of th e va lve w hich a re not pa rall elto its marg in . Accordi ng to Or. Q. S IDDIQLJ I (pe rsona l com mun icatio n), s ince the muscl e scars o f th espec imens a re unknown , it would be bette r to refer th em to Rab ilim is o nly tentati vel y. Prof. R. WII ATLEY(pe rsonal com municatio n) suggests th at thi s for m is probabl y conge ne ric with a new genus w hic h WII AT­LEY et al. have desc ribed (i n press ) fro m Pat agon ia .

Distribution. - Pecten Cong lo merate (Pliocene) fro m Cockburn Island .

Ge nus Procytlt ereis S KOGSBERG, 1928Procytliereis cl'. robusta SKOGSBE RG , 1928

(PI. 39: 2-3)

Material. - One aC and o ne aLV fro m th e Swed ish collec tio n.

182 JA NI NA SZCZECHU RA and JA N USZ BLASZY K

Remarks. - The spec ime ns are badl y preserved . However, they seem to have uni forml y di st ributedpits over the e ntire va lve surface, as in the Recent Antarct ic spec ime ns, referre d to by S KOGSBERG ( 1928)as Cyt hereis tProcythereis) robusta . In compa rison with specime n fig ured by SKOGSBERG (l .c. ) o urProcythereis cf. robusta ind iv idua ls seem to be less d istinctl y ribbed posteriorl y and ventrol ate rall y.Moreover, the rig ht va lve s of the co mpa red spec ies di ffe r, righ t va lve o f Procythereis cf. robusta spec iesbe ing more rec tang u lar. Discu ss ion conce rn ing diffe ren ces between Hemicyth ere kerguelen en sis (BRADY,1880 ), Hemicythere sp . aff. H. kerg uelen en sis (BRADY, 1880 ) described by BENSON ( 1964) and Cythereis(Procy tlzereis) robusta SKOGSBERG ( 1928), i.e . a ll these Recent species fro m the Antarctic area, is g ive nby BENSON ( 1964). Accordi ng to thi s last autho r specime ns with the most uni form puncta are typical ofthe more no rthern populati on s i.e. beyond the she lves aro und Anta rctica. HARTMANN (l.c .) referredProcythereis rob usta SKOGSBERG, 1928, to the subgenus Se rratocythereis.

Distribution . - Pecten Cong lo me ra te (P liocene) fro m Cockburn Island. Procythereis robusta S KOGS­BERG ( 1928), descr ibed as a Recent spec ies fro m So uth Georg ia, was found later by HARTMANN ( 1986,1990) in Antarctica, in the South S he tland Island s and around the Antarctic Pen insul a.

Ge nus A ust ra licythere BENSON, 1964A ustralicythere polylyca (G .W. M UL LER, 1908)

(PI. 43: 1- 5)

1908 . Cythereis polvlyca M ULL ER n. sp .: p. 135. text-fi gs 1- 4, pI. 17: I. 5-6.

1964 . Australicyt here polylvca (M OLLER). 1908; BENSO N. p. 24, text-fi gs 15- 17. pl. 2: 10. pI. 4: 1- 7.

1967. Australicythere polylvca ( M OLLER) 1908; NEALE, p. 36. text -fig. 12, pI. 4: e. k-n .

1990 . Australicythere polylvca (G .W. M OI.I .ER. 19(8); H ARTMANN. p. 204. pI. I : 8-9; pl . 2: 10-1 5.

Material. - One aC and two aRV from the Swed ish co llec tio n, and one aC and one aRV fro m thePo lish co llec tio n, all rath er badl y preserved .

Remarks. - The spec ime ns referre d to the spec ies vary so mewha t in the det ail s of thei r orname nta­tion . Th ey also d iffer s lig htly from spec ime ns referred to A ustra licythere polylyca (BENSON 1964 ; HART­MAN N 1986, 1990). In compariso n wi th (some) of B ENSON's and HARTMANN'S (l .c.) specimens , theyge ne ra lly are lackin g the fin e , almost ve rtica l posteri or rib. Some of th e speci me ns illus trated by BENSON(l.c. pI. 5 : 4) also lack th is rib .

Distribution . - Pecten Cong lo merate (Pliocene) from Cockb urn Island. Recent o f Antarc t ica i.e. lat.65°S; lon g. 90

0 E (Gauss Sta tio n) tc]. NEAL E 1967 ), McMurdo Sound (BENSON 1964 ), Hall ey Bay (We ddellSea) see NEALE ( 1967), and the A ntarctic Pen insul a area (HARTM ANN 1990).

Genus Patagonacythere HARTMANN, 1962Patagonacyth ere cf. lon giducta lon gidu cta (S KOGSB ERG, 1928)

(PI. 44: 2, 4 , 6 ; ?PI. 44: 3, 5)

Material - One aC , aLV from the Swed ish collec tio n, and o ne eC, one aRV and one aLV from thePoli sh collec t ion.

Remarks. - The Pecten Co ng lo merate spec imen seems to di ffer s lig htly from the Recen t A ntarc ticmateri al , refe rre d to Patagonacvthere longiducta (SKOGSBERG) by HARTMANN ( 1990) . In compar iso n withHARTMANN'S ad ult specime ns the present material has a di sti nct , a lmost ve rtical ridge j oining the posteri orend of the ve ntro latera l rib and the posterodor sal loop . This featur e is characterist ic o f SKOGSBERG 'S fo rm.Similar di fferen ces are observed bet ween speci me ns collected in Mc M urdo Sound (Ross Sea) by BENSON( 1964) and also figured by SKOGSI3E RG ( 1928), and this allowed BENSON (l.c.) to erect the ne w subspecies,p. lon giducta an tarctica.

Distribution. - Pecte n Co ng lo me rate (Pliocene) from Coc kburn Island. Pat agonacythere lon giductalon gidu cta is known as a Recent form fro m South Georg ia (SKOGS BERG 1928) and the A nta rc tic Pen insul a(HARTM ANN 1990).

Patagonacythere cf. tricostata HARTMANN, 1962(PI. 44: I)

Material. - On e aC fro m the Poli sh collectio n.Remarks. - The sha pe o f ca ra pace as we ll as the arrangeme nt of its main morphological features i.e.

posterio r, medi an and later oventral rib s, and the type of o rname ntat io n, seem to be si milar to those

OST RACODS FROM T HE PECTEN CONGLOME RATE 183

charact eri stic of Pata gona cyth ere tricostata , a Recent spec ies described from Pat agoni a and southernChile. In co mparison with the holotype of Patagonacythere tricostata the Pli oc en e spec ies is higher andmore densely reticulated . WIIATLEYet al. ( 1995) referred Patagonacythere tricosta ta into the Ambostraco n(Patagonacythere v tricostata group, cha rac te ristic of the Terti ary of so uthern South Ame rica .

Distribution. - Pecten Cong lome rate (Pliocene) fro m Cockburn Island. Patagonacythere tricosta taHARTMANN occurs at the present in the South-Eastern Atlantic (HARTMANN 1962) as we ll as in theSo uth- Western Atla ntic (a long the co ast of East Fa lkla nd) see WHATLEY et al. ( 1995) .

Genus Me ridio nalicythere WHATLEY, C IIADWICK , COXILL et To Y, 1987'lMeridionalicyth ere sp.

(PI. 40: 6)

Material. - On e ?jC from the Poli sh collecti on .Remarks. - Th e ge nera l ex te rna l app earance of the spec ime n, mostl y its sha pe , i.e. subtrapezoidal

lateral outline and lateral inflation s, including the subce ntral elevat ion and eye tub ercle-like inflation, arereminiscent of the morphological features typical of Meridionalicythere. Th e smooth valv e surface is likein the juvenile representatives of the Recent spec ies 'tMeridionalicyth ere sp . de scribed by WHATLEY et al .(1987 ) from the southweste rn Atlantic. Pliocen e spec ime n, however, bear more dev eloped posterodorsaland posterov entral infl ation s.

Distribution. - Pecten Cong lome rate (Plioce ne) from Cockburn Island.

Family Loxoconchidae SARS, 1925Genus Antarcti loxoconcha HARTMANN, 1986Antarctiloxoconch a frig ida (NEALE, 1967)

(PI. 45 : 2-5)

1967. Loxocythere frigida N EAI. E sp, nov.: p. 29. pl, 2: 9.

1988. 'tCvtheropteron [rigidum (N EAI. E). 1967; WIl t\TI. EY. CIl t\I>W ICK. COX 11.1. and To y; p. 183. pI. 4 : 3-5.

1990 . Antarctiloxo conchu [rigida (NEAI.E. 1967); H ARTMANN. p. 205 . pI. 4: 30.

Material. - On e aLY and one aRY from the Sw edi sh co llection, and one aC and one ?jC from thePoli sh co llection.

Remarks. - HARTMANN ( 1990) put into the sy nony my of thi s species his spec ies Antarctiloxoconcharotundica udata. For an additiona l rem arks see WHATLEY et al . ( 1988). Th e spec ime n on PI. 45 : 2 is rathertentat ively regarded as ju venil e .

Distribution. - Pecten Cong lome rate (Pliocene) from Cockburn Island , Recent o f Antarcti ca i.e. theHall ey Bay (Wedde ll Sea ) see NEALE (1967) and the Antarctic Peninsula area (HARTMANN 1990).

Family Cytheruridae G.W. M ULLER, 1894Genus Sem icytherura W AGNER, 1957

TSemicythe rura sp.(PI.4 1:3)

Material. - On e ?aC fro m the Swedis h co llection.Remarks. - A c lose d and badl y preserved ca ra pace does not allow of a defin ate ge ner ic determina­

tion. Its ge neral appearance , however, allows us to re fer it (tenta tive ly) to Semicyth erura. It see m to becovered e ntire ly by deli cate, hori zontall y ar ranged rib s .

Distribution. - Pecten Cong lomerate (Pliocene) fro m Cockburn Island .

Genus Hemi cyth eru ra ELOFSON, 1941Hemicyth erura cf. reticu lata HARTMANN, 1962

(PI. 41 : 5)

Material. - On e aC from the Poli sh coll ecti on .

Remarks. - In its ge nera l shape as we ll as type of o rna me nta tio n, the ca rapace see ms similar toHemicytherura reticu lata HARTM ANN, 1962, a Recent spec ies from the South-Western Atlantic . In com­pari son with HARTMANN's spec ies, the Plioc ene form is more pronouncedly rimmed along its margins,exce pt ante riorly, and it has coarse r pun ctation , limited to its ce ntral part.

184 JANINA SZCZECHU RA and JANUSZ BLASZYK

Distribution . - Pecten Co ng lo me rate (Pliocenc) from Cockburn Island. Hemicytherura reticu lataHARTMANN, 1962, is known. as a Recent spec ies, from Southern C hile, Ma gellan Strait , Eas t Falkland.and so uthern Arge ntina (Prov ince of Santa Cruz) see WIIATLEY et al. ( 1988). WHATLEY et al. ( 1995) .

Genus Cyt heropteron SARS. 1866TCytheropteron sp.

(PI. 45 : I )

Material - On e aC fro m the Poli sh collec tio n.Remarks. - The ge ne ra l appeara nce o f the carapace i.e. its se miovate lat er al outline. weakly (ind is­

tinc tly) de vel oped ve ntro la teral alae and mod er ate lat eral infl ati on , as we ll as the type of o rna me ntationwhich cons ists of coarse punct a. best devel op ed and distributed in its posterodorsal part. suggests that thi sspec ime n belongs to an unkno wn spec ies.

Distrib ution. - Pecten Cong lo me rate (Pliocenc) fro m Coc kburn Island.

Genus Loxo reticulatum BENSON. 1964'll.oxore ticu latum sp.

(PI. 41 : 4)

Material. - One badl y preser ved 'laC from the S we d ish co llec tion.Remarks. - Th e ex te rna l appe arance o f the carap ac e i.e. its subrho mbo ida l latera l outline . and the

posterolater al com press io n. di stinct arc hed rib a long the dorsal marg in. we ll marked ve ntro late ra l rib andthe typ e of orname ntatio n allows thi s spec ime n to be tentati vel y refer red to Loxoreticulatum, Th e typ e oforname ntatio n of the carapace, co ns isting of lo ng itud inal ribs and rathe r rare but large punct a, differs fromknow n species of Laxoreticulatum ,

Distribution. - Pecten Cong lome rate (Pliocene) from Coc kburn Island .

Famil y un kn ow nGen. e t sp. incert .

(PI. 42 : 8)

Material. - On e 'laC from the Poli sh collec tio n.Remarks. - The ca rapace almost egg-sha ped, so mewha t trun cat ed posterod orsall y and anterodo rsally,

ind istinc tly com pressed posteri orl y. w ith a weak and obliq ue sulcus ce ntrodo rsally. Nearly the entireca ra pace sur face is fin el y and irregul arl y reticula ted. and pun ct ate .

Dist ribution. - Pecten Cong lo me rate (Plioccne) from Cockburn Island .

REF EREN CES

AI':DEKSso l': . l .G. 1906. On the geo logy of Gra ham Land . - Bullettin of the Gco logica i lnstit ute of the University I!{ Upsala7. 19- 71.

ASKI I': . R.A.. EI.I.IOT. D.H.. STII.\\, I;I.I.. 1.D. and ZI I': S~ IE I STEK . W.J . 1991 . Stratigrap hy and pa leontology of Campanian andEocene sediments, Cockburn Island. Antarct ic Peninsula. - Jou rnal of South American Earth Sciences 4. 99- 117.

B"RNES. R.P. and RIDI NG. 1.B. 1994. Angular unconformity between the Lopez de Bertodano and La Mese ta Formations(Campanian-Maastrichtian and Eocene). Cock burn Island. northern Antarctic Peninsula. - Journal o] South AmericanEarth Sciences 7. 35-44.

13 "KTOI': . C. M. 1965. The geology of the Sout h Shet land Islands. Ill. The stratigraphy of King George Island. - BritishAntarctic Survey, Scientific Reports 44. 1- 33.

I3 ENSOI': . R.H. 1964 . Recent Cytheracean Ostracodes from McMurdo Sound and the Ross Sea. Antarctica. - The Unive rsitylif Kansas Paleontological Con tributions, Arthropo da 6. 1- 36.

I3IRKEI':~ I "J EK . K. 19R2. Pliocene tillite-bearing succession of King George Island (South Shet land Islands. An tarctica) . ­SII/(Iia Geologica Polonica 74. 7-72.

BI R K EN ~I AJ EK . K. and G" i.DZICK I. A. 19R6. Oligocc ne age of the 1'1'1'11'11 Conglomerate on King Geo rge Island. WestAntarctica. - Bullet in I!{ the Polish Academy lif Sciences, Earth Sciences 34. 2 19-226.

BIR KENMAJ ER. K.. G" i.nzIC KI . A.. GR"nzINsK I. R.. KREUZER. H.. PORI;IlSKI . S.J. and TOK" Ks KI. A.K. 1991. Origin and ageof pect inid-bearing conglomerate (Tertiary) on King George Island. West Antarc tica. Ill: M.R.A. Thom son, 1.A. Crameand 1.W. Thornson (eds) Geolog ical Evolution o] Anta rctica . 663-665 . Ca mbridge University Press.

OSTRAC ODS FROM T HE PECTEN CONGLOMERATE 185

BLASZYK, J . 1987 . Ostracods fro m the O ligocene Polon ez Cove Fo rma tio n of Kin g George Isl and, W est A ntarc tica. In:A . Gazdz ick i (ed .) Pal aeont ologi cal Results of the Poli sh A nta rctic Ex ped itions . Part I. - Palaeont ologica Polon ica

49 , 63- 81.BROUWERS, E.M . and M ARI NCOVICII, Jr., L. \ 987. Ostracode and Molluscan Assemblages fro m the Late Neogen e Nuwok

Member o f the Sagavanirktok Forma tio n, North S lope . - Geologic Studies in A laska by the u.s. Geolog ica l Surveyduri ng 1987, 24-26.

COI.I'S, G .. AYREss, M. and W IIATI.EY, R. 1990. A compariso n o f North Atla ntic and Pacifi c Cainozoic deep -sea Os tracoda .In : R. Wh atl ey and C. Maybury (eds) Ost raco da and Global Events , 287-30 I . C ha pma n and Hall . London-New

Yor k- Tokyo-Melbo urne-Madras .CRONIN. T M. 199 I. Late Neogene marin e O stracod a fro m Tjornes, Iceland . - Journal of Pal eont olog v 65 , 767-794.CRONIN. T .M . and IKEYA, N. 1987. T he O mma- Ma ng anj i Os tracod fauna (Plio- Pleistoce ne) of Jap an an d the zoogeography

of circ umpo lar species . - Journal of Micropa laeontologv 6 . 65 -88 .DOKTOR. M ., G AZDZICKI. A ., M ARI 'NSSI, S.A., PORI;IlSKI, S.L S ANTII.I.ANA. S .N . and VRIlA, A. V. 1988. Arge ntine - Po lis h

geolog ica l investigation s on Seymour (Marambio) Islan d , A nta rc tica , 1988 . - Poli sh Polar Research 9, 52 1-54 1.ECIIEV ARRIA, A .E . 199 I. Ostracodos del O ligoceno del sudcs te del Lago Cardie l, Santa C ruz , Argentina . - /unegh inia na .

267 -285 .G AZDZICKA, E. and G AZDZICK I, A . 1985 . O ligocene cocco liths of the Pecten Co ng lome ra te on Kin g George Islan d , W est

An tarc tica. - Neues Jahrbuch fii r Geo logic und Pal iiontolog ie, Mon at shefte 12, 727-735 .G AZDZICKA, E. and G AZDZICK I. A. 1994 . Recycled Upper C retaceous ca lca reo us nann o plan kton from the Pecten Co ng lome­

rate o f Coc kb urn Island , Antarc tica . - Pol ish Polar Research 15 . 3- 13.G AZDZICKI, A . and WUlB. P.N . 1996 . Fo rami ni fera from th e Pecten Co ng lomerate (Plioce ne) o f Cockburn Island , Anta rctic

Peninsul a . In : A. Gaidzicki (ed.) Pa laeonto log ica l Results of th e Polis h A nta rc tic Exped itions . Part 11 . - Pala eont ologiaPoloni ca 55 , 147-1 74.

HARWOOD, D.M . 1986. Diatom biostra tigraph v and paleoeco logv with a Cenozoic history of Anta rctic ice shee ts . ­Unpub lished Ph . D. di sse rtation . Th e O hio Sta te Univers ity , Co lumb us , 592 pp.

HAR"nl ANN, G . 1962. Ostracodendcs Eulitora ls. In : G . Hartrnan n-Sch roder and G . Hartm ann (eds) Zu r Ke nntnis de s Eulitoralsder chi le nisc he n Pazifik kuste und der arge ntinisc he n KUste, SUdpatagoniens unt er besonderer BerUck sichtigun g derPol ych aet en und Ostracode n. - Mi tteilun gen aus dem Hamburgi sch en Zoo logisch en Mu seum und lnstitut 60 suppl.,169- 27 0 .

HARTMANN, G . 1986. Antark tisc he bent isch e Os tracode n I (M it e iner Tabe lle der bislan g aus de r A ntarktisc h bek ann tenO stracode n) . - Mitt eilungen aus dem Hum burgischen Zoo logischen M useu m und lnst itu t 83. 14 7- 221.

HARTMANN, G . 1990 . A ntark tisc he bentisch e Os tracode n V I Aus wert ung de r Rei se der "Polarstern" A nt. V I-2 ( I. Te il,Meio faun a und Ze hnerserien) sow ie Ve rsuc h e iner vorlaufigen A uswe rtung a ller bislan g vor liegenden Daten ). ­Mitt eilungen aus dem Hamburgisch en Zoo logischen Museum 11/111 ln stitut !l7 , 191 - 24 5.

HENNI C;, A. 191 0. Le Co ng lo mera t plei stocen e a Pecten de l' Ile Cockburn . - wissensc haft liche Erg ebn isse der SchwedischenSiidpo lar-Expedition 1901-1 9033 ( 10), 1-73 .

HORNIBIWOK, N. de B. 1953 . Tertiary and Recent marin e Ostracoda of New Zea land - their origi n, affini ties, anddi str ibut ion. - New Zea land Geo logica l Su rvev, Palaeont ological Bulletin 18, 5-82.

IRI /.u KI. T 1994. Late Miocene ostracods from the Fuji ko togawa Formation, northe rn Jap an - w ith re ference to co ld wate rspec ies involved wi th tran s-A rc tic interch an ge. - Journal of Micropa laeontologv 13, 3-1 5 .

KEI.1l0 WICI.. A.A . 1988. Upper O ligocene - Lower Mi ocen e Os tracods from th e YP F. SCA . ECa X-I (E l Cam pamento)Bo reho le. A ust ra l Bas in , A rge ntina. In: R. Wh atl ey and C. May bury (ed s) Ostracoda and Global Events, 1125-1 145.C ha pman and Hall. London- New York- Tokyo- Melbourne- Madras.

NI'AI.E, J .W . 1967. A n os tracod fauna fro m Hall ey Bay , Coats La nd, Briti sh A ntarc t ic Territory . - British Antarctic SurvevScien tific Report s 58 , I- 50 .

S IDDIQUI, Q .A . 1988. T he Iper k Se que nce (P lio -P lcistocene l and its Ostracod Assemb lag es in the Ea ste rn Beaufort Sea. In :T Han ai. N. Ikeya and K. Ishi za ki (cd s) Evo lutionary bio logy of ostracoda itsfundamentals and applications , 533-540 .Devel o pm ents in Palaeon tol ogy and Stratigraphy 11, Kod an sh a- Else vie r, Tokyo.

SK()(;SIlERC . T 1928. St udie s on marine ostracods . part 11 . Ex te rna l mor ph ology o f the gcn us Cythereis w ith desc ripti on oftwen ty-on e new species . - Ca lifo rn ia Academv (If Sciences. Occasio na l Papers 15 , I- 55 .

SKOC ;SflERC, T 1939 . A new ge nus and spec ies of marine ost racods fro m South Geor gia . - Ca lifo rnia Academy of Science,Proc. 33, 41 5-425.

SWAIN, F.M . 1963. Pleistocen e O stracoda fro m the G ub ik Fo rmat io n, Arct ic Coasta l Plain, A laska. - Journal of Pal eonto­logy 37 , 798-834.

SZCZECIIlIR A, J . 1994 . Pal eogeogr aph ic meaning o f psychrosp heric Mi ocen e os tracodes fro m th e Fore-Carpa th ian De press­ion. - Acta Geo log ica Polon ica 44, 137-1 51 .

SZCZEClIlIRA, 1. 1995 . T he os traco d ge nus Xvlocythere Maddock s and S te ineck, 1987, from th e M idd le Miocene of theFo re-Carpat hia n Depressi on , so uthe rn Pol and (Ce ntra l Parate thys ). and its s igniti cance as an ind icator of past ocean icpath ways. - Acta Geo log ica Polon ica 45 , 3 1-44.

WE llfl, P .N . an d A NDREASEN, J .E. \ 986. Pot ass ium-ar gon da ting of vo lca nic mat erial assoc iated wi th the Pli oceu e Pect enC ong lomerate (Coc kbur n Island ) and Sc a llo p Hill Formation (Mc M urdn Sound) . - Antarctic Journal of the UnitedStales 21 (5),59 .

WIIATI.EY, R.. C IIADWICK , 1.. COXILL. D. and Toy . N. 1987 . New ge nera and spec ies of cy theracean Os tracoda fro m theS .W . Atlantic . - Journal of Microp aleont olog v 6. 1-1 2.

)/YX2A~iH S2UVlA l bnn M IUI-I::EIX:)X2 A VlIVlA l 08/

OfIJ; :Jil:m;lnA :lfh mott :mbi1u1:Jrh() '(Iirfll;l boomrao erfT .XX(I( .V1 .v o'T bnn .0 ..I.I IX<O ,.t .)lJ I'I/< IIII O ,.51 : r:UTtd 'W.£0 5:- 1I I ,OS: ni:J,\)\ \l\ II\)"lIl)\\ \)"\' liM "lll n\\)\'Il\\i::l IwilTI9. - .:Jilfll;llA l ~::lW-rflu02

.2 .J ,nir;w2 .M.' :11\ . ~l :Jl r;w ::lniln::lg1A ni :Jr;bil:Jrll'(Jo lq:JJ '(lirrlf;1 orl'T .c I(l 1 .A , Y )l~V~u l u,)()M bnn .:::>.51 ,Y:I.ITlllfWI f-~ I ,:J1r;wl;1:J0 '10 '( l i~l:Jv i nU ff1uiw qffl'(2 A .n\)\)")1YI\1,O \.\) · '.~.\)h)i \\ \) "l\ Il\\ \ )\In ''.ll,I)\ \)iH ( ~b:J ) nibnu.I ., .51 bnu l :J;.birno)l

.15: c- IOc ,5:1(1 1 ,lwguAofll;IJlI,;, :JrfT .I tu;q ,:JilnGllA l ~:JW rfluo2 :]rfl rfl(Jlll; oO:Jli1l~O ,c(l(l l .0,.1. 11 )« 0 bnn ,A . Y )I ~v:l.lI u , )()M ..V1 .YoT ..51 .Y:I .lTlllfW

.X£- \1 .I S: ni ll,\)\\)\\\\ n \ Il\\\)'l')iM "lll n\()\,\),\?.'::\. n\7:I'I"I9. - .zbnnlal') i \,)'\I)\II!\ - .bnnlal rnudJl:Jo:::> 'to '(go IOlnlJ:) (r;q bnn '(go lo:Jg '('IG itI::lT- WO:l:J!; l:ll:::> .5:8(1 1 .V1-.q .HlEfW bnn .LW . }{ :IT~E f M~ iI1 IS

. 5: l:>- I ~ ,( c ) \I '/,"I\ n \'l . \l"l\i IlU "II\I,\) \\)\ n1\\l \'

Palaeontologia Polonica, No. 55, 1996

J. SZCZECHURA and J. BLASZYK: OSTRACODS FROM THE PECTEN CONGLOMERATE (PLIOCENE)

OF COCKBURN ISLAND, ANTARCTIC PENINSULA

PLATE 39

Copytus ealigula SKOGSBERG, 1939 .

Fig. 1. aC, a - left side, x 80 b - right side, x 80, C - dorsal view, x 70 , Ar 54429 .

Procythereis cf. robusta SKOGSBERG, 1928 . . . . . . . . . . .

Fig. 2. aC, a - dorsal view, b - ventral view, C - left side , d - right side, x 70 resp., Ar 54427 .Fig. 3. aLV, seen from outside, x 60, Ar 54426.

180

181

Palaeontologia Polonica, No. 55, 1996 PI. 39

J. SZCZECHURA and J. BLASZYK: OSTRACODS FROM THE PECTEN CONGLOMERATE (PLIOCENE)

OF COCKBURN ISLAND, ANTARCTIC PENINSULA

Palaeon tologia Polonica, Nu. 55, 1996

J. SZCZECHURA and J. BLASZYK: OST RACO DS FROM THE PECTEN CONGLOMERATE (PLIOCENE)OF COC KBURN ISLAND, ANTARCTIC PEN INSU LA

PLATE 40

?Leptocythere sp. 181

Fig . I . aC, a - somewhat oblique view of the right side , x 110, b - right side, x 90, C - right side, x 95, d - ventralview, x 76, e - dorsal view, x 74, ZPAL O.xXXVII/9.

Fig . 2. aC, right side , x 95, ZPAL O.xXXVIU8.

?Loxocythere sp. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180

Fig. 3. jLV, a - somewhat oblique dor sal view, x 60, b - seen from outside , x 66, ZPAL O.xXXVIU1I.Fig . 4 . aRV, a - seen from outside, x 58, b - seen from inside , x 58, Ar 54430.Fig . 5. Hinge margin of aRV, x 78, Ar 54414.

?Meridionalicythere sp. . . . . . . . . . . . . . . . . . . . . . . . 180

Fig. 6. ?jC, a - oblique view of the right side, x 233, b - right side, x 233, ZPAL O.XXXVIUIO.

Palaeontologia Polonica, No. 55, 1996 n. 40

J. SZCZECHURA and J. BLASZYK : OSTRACODS FROM THE PECTEN CONGLOMERATE (PLIOCENE)

OF COCKBURN ISLAND , ANTARCTIC PENINSULA

Palaeontologia Polonica, No. 55, 1996

J. SZCZECHURA and J. BLASZYK: OSTRACODS FROM THE PECTEN CONGLOMERATE (PLIOCENE)OF COCKBURN ISLAND, ANTARCTIC PENINSULA

PLATE 41

Pseudocythereis spinijera SKOGSBERG, 1928 .... .Fig. 1. aC, a -left side, x 67, b - right side, x 67, c - dorsal view, x 60, Ar 54415.Fig. 2. aLV, a - seen from outside, x 67, b - seen from inside, x 7, Ar 54416.

?Semicytherura sp. . .

Fig. 3. ?aC, a - right side, x 116, b - dorsal view, x 114, Ar 54431.

?Loxoreticulatum sp.

Fig. 4. ?aC, right side, x 153, Ar 54432.

Hemicytherura cf. reticulata HARTMANN, 1962 .

Fig. 5. aC, a - right side, x 138, b - oblique view of the right side, x 132, ZPAL o.xxxvnn.

181

183

184

183

Palaeontologia Polonica , No. 55, 1996 Pi. 41

J. SZCZECHURA and J. BLASZYK : OSTRACODS FROM THE PECTEN CONQLOMERATE (PLIOCENE)

OF COCKBURN ISLAND , ANTARCTIC PENINSULA

Palaeontologia Polonica. No. 55, 1996

J. SZCZECHURA and J. BLASZYK : OSTRACODS FROM THE PECTEN CONGLOMERATE (PLIOCENE)OF COC KBURN ISLAND, ANTARCTIC PENINSULA

PLATE 42

?Rabilimis sp. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181

Fig. I. aLV. seen from outside, x 11 7, Ar 54422 .Fig. 2. aC, left side, x 86, Ar 54420 .Fig. 3. aC, a - oblique view of the right side, x 104, b - right side, x 94, ZPAL O.XXXYII/l 2.Fig. 4. aC, left side, x 94. Ar 54423.Fig. 5. aLY, seen from inside. x 76. Ar 5442 1.Fig. 6. aC, a - ventral view, x 73, b - right side, x 94, ZPAL O.XXXYII/I .Fig. 7. aLY. seen from outside. x 96. ZPAL O.XXXY II/l4 .

Gen. et sp. incert. . . . . . . . . . . . . . . . . . . . . . . . . .

Fig. 8. ?ac' a - oblique view of the right side. x 83, b - right side. x 77. ZPAL O.XXXYII/4.

184

Palaeontologia Polonica, No. 55, 1996 PI. 42

J . SZCZECHURA and J. BLASZYK : OST RACODS FROM THE PECTEN CONGLOMERATE (PLlOCE NE)

OF COC KBURN ISLAND, ANTARCTIC PENINSULA

Palaeontologia Polonica, No. 55, 1996

J. SZCZECHURA and J. BLASZYK: OSTRACODS FROM THE PECTEN CONGLOMERATE"(PLIOCENE)OF COCKBURN ISLAND, ANTARCTIC PENINSULA

PLATE 43

Australicythere polylyca (G.w. M ULLER, 1908) 182

Fig. I. aLV, seen from outside, x 77, ZPAL O.XXXVII/l 8.Fig. 2. aC, a - oblique view of the right side, x 68, b - ventral view, x 74, c - right side, x 78, ZPAL O.xXXVIU2.Fig. 3. aRV, a - seen from outside, x 77, b - seen from inside , x 77, Ar 54419.Fig. 4. aC, left side, x 76, Ar 54418 .Fig. 5. aRV, seen from outside, x 75, Ar 54433 .

Palaeontologia Polonica, No. 55, 1996 PI. 43

J. SZCZECHURA and J. BLASZYK : OSTRACODS FROM THE PECTEN CONGLOMERATE (PLIOCENE)

OF COCKBURN ISLAND, ANTARCTIC PENINSULA

Pala eontologia Polonica. No. 55. 1996

1. SZCZECHURA and J. BLASZYK: OSTRACODS FROM THE PECTEN CONGLOMERATE (PLIOCENE)OF COCKBURN ISLAND, ANTARCTIC PENINSULA

PLATE 44

Patagonacythere cf. tricostata H ARTMANN, 1962 .

Fig. I . aC, a - oblique view of the right side, x 87, b - right side, x 94, ZPAL O.XXXVII/l 5.

Patagonacythere cf. longidu cta longidu cta ( SKOGS BERG, 1928)

Fig. 2. aLV, seen from outside, x 62, ZPAL O.XXXVII/l 7.Fig. 4. aRV, seen from outside, x 93, ZPAL, O.XXXVII/16.Fig. 6. aLV, a - seen from outside, x 62, b - seen from inside, x 75, Ar 54425.

?Patagonacythere cf. longidu cta longidu cta ( SKOGSB ERG, 1928)

Fig. 3. aC, right side, x 60, Ar 54424.Fig. 5. aC, a - oblique view of the right side, x 80, b - right side, x 77, ZPAL O.XXXVII/3.

182

182

182

Palaeonto logia Polonica. No. 55, 1996 PI. 44

1. SZCZECHURA and 1. BLASZYK: OSTRACODS FROM THE PECTEN CONGLOMERATE (PLlOCENE)

OF COC KBURN ISLAND, ANTAR CT IC PENINSULA

Palaeontologia Polonica, No. 55, 1996

J. SZCZECHURA and J. BLASZYK : OSTRACODS FROM THE PECTEN CONGLOMERATE (PLIOCENE)OF COCKBURN ISLAND, ANTARCTIC PENINSULA

PLATE 45

?Cytheropteron sp. 184

Fig. I . aC, a - oblique view of the right side, x 114, b - right side, x 117, c - right side, x 155, ZPAL O.xXXVIl/ I9 .

Antarctiloxo concha frigida (NEALE, 1967) 183

Fig. 2. jC , a - oblique view of the rigt side, x 116, b - right side, x 138, ZPAL O.xXXVIl/6.Fig. 3. aRV, a - seen from inside, x 95, b - obliquely seen from outside, x 114, Ar 54434.Fig. 4. aLV, a - seen from inside, x 94, b - seen from outside, x 112, Ar 54435 .Fig. 5. aC, a - oblique view of the right side, x 103, b - oblique view of the right side. x 95. c - right side, x 98,

ZPAL O.xXXVIl/I 3.

Palaeontologia Polonica, No. 55, 1996 Pl.45

J. SZCZECHURA and J. BLASZYK : OSTRACODS FROM THE PECTEN CONGLOMERATE (PLIOCENE)

OF COCKBURN ISLAND , ANTARCTIC PENINSULA