BollettinoMalacologico,Roma,38(1-4):41-44,2002-SocietàItalianadiMalacologia The shallow-water Polypiacophora of the Azores and some comments on the biogeographical relationships of the Azorean malacofauna Sergio P. Avila & AndréAlbergaría KEYWORDS! Polypiacophora,Azores,biogeographicalrelarionships. ABSTRACT TheMollusc'sreferencecollectionoftheDepartmentofBiologyoftheUniversityoftheAzores(DBUA)wascheckedforPolypiacophora. Ataxono- miclistisgivenand newdataisprovidedregardingthegeographicdistributionand bathymetric rangeoftheAzorean Polypiacophora. Somecom- mentsaremadeaboutthebiogeographicalrelationshipsofGastropoda,Bivalvia,Cephalopodaand PolypiacophoraoftheAzores. RIASSUNTO E’stataanalizzatalacollezionemalacologicadi riferimentodelDipartimentodi Biologiadell'UniversitàdelleAzzorre(DBUA),considerando i soli Poliplacofori.Vienepresentataunalistaenuovidatiriguardantiladistribuzionegeograficaed ilrangebatimetricodei Poliplacoforiedalcuniaspet- tidellerelazioni biogeografichediGasteropodi,Bivalvi,CefalopodiePoliplacofori. SERGIOP. ÀVILA^ &ANDRÉALBERGARIA- Sec^àodeBiologiaMarinha,DepartamentodeBiologia,UniversidadedosAzores9500PontaDel- gada,Azores,Portugal. 1,email:[email protected];2,email:[email protected] INTRODUCTION RESULTS Among the few works that have been published about the A total of801 samples ofthe DBUA collection were studied, shallow-water Polypiacophora ofthe Azores during the last cen- ofwhich 53 yielded Polypiacophora. tury, the majority dealt with the systematics and distribution of Of the six species of Polypiacophora reported from the Azo- this group (Dautzenberg, 1889; 1927; Kaas & Van Belle, res,Acanthochitona discrepant is considered to be a dubious record 1981; 1985a; 1985b; Mac Andre'w, 1856; Macedo et al., and three species were confirmed by us: Hanleya hanleyi, Lepido- 1999; Nobre, 1924; Van Belle, 1984). Only in the last decade chitona simrothi and Acanthochitonafasciadaris. The most com- the ecology ofthis class has been studied (Azevedo, 1991; Bul- mon Polypiacophora in the Azores are A. fasciadaris and the lock, 1995; Hawkinsi/zz/., 1990; Mortonerzz/., 1998). endemic species L. simrothi, appearing in 52 out ofthe 53 repor- It is our intention to provide new data about the geographic ted samples. The Azorean Polypiacophora have higher similari- distribution and bathymetric range within the Azores of the ties with the Canary Islands, Boreal Province (Scandinavia and species of this class and to establish the biogeographical rela- British isles) and the Lusitanian Province (mainland of Portu- tionships ofthe marine malacofaunaofthe Azores. gal) than with the Madeiraor the eastern coast ot north America (seeTable 1). MATERIALS AND METHODS Polypiacophora from the Mollusc's reference collection of the TAXONOMIC LIST Department ofBiology ofthe University ofthe Azores (DBUA) Phylum MOLLUSCA were studied. The Polypiacophora in this collection were sampled Class POLYPLACOPHORA between 1989 and 1999 by diving at depths up to 45 m. Dives Order LEPIDOPLEURIDA were made by the Marine Biology team ofthe University ofthe Eamily Hanleyidae Azoresat Pico, Faial, Flores, SaoMiguel and Formigas islets. Hanleya hanleyi(Bean in Thorpe, 1844) A literature review was made and information included in Hanleya hanleyi (Bean in Thorpe, 1844). Azores (Kaas & Van the taxonomic list presented. Belle, 1985a: 193-196). Species were identified using Kaas & Van Belle (1985a; Material examined: DBUA 551 (Portoda Baleia, Flores). 1985b; 1987; 1990; 1994) and the classification follows the Bathymetry: from 15 down to 555m depth (Kaas & Van CLEMAM database. All specimens were measured to the nearest Belle, 1985a). mm. Dorsal elevation is the tatio height of tegmentum/width Dimensions: length = 7 mm; breadth = 4 mm; dorsal elevation (see Kaas&Van Belle, 1985a). = 0.3. >41 < SérgioP.Avila&AndréAlbergada Table 1: Geographic distribución ofthe Azorean Polyplacophora. AZO—Azores; MAD—Madeiraarchipelago; CAN—Canary Islands; BRI — British isles; POR — mainland ofPortugal; MED — western Mediterranean; SCA — Scandinavia; AME — eastern coasr ofn^rth America. 1- presence, 0—absence. AZO MAD CAN BRI POR MED SCA AME Hanleyahanleyi 1 1 1 1 1 1 1 1 Callochitonseptemvalvis 1 0 1 1 1 1 1 0 Lepidochitonapiceola 1 0 1 0 0 0 0 0 Lepidochitonasimrothi 1 0 0 0 0 0 0 0 Acanthochitonafascictdaris 1 1 1 1 1 1 0 0 % Shared species 100.0 40.0 80.0 60.0 60.0 60.0 40.0 20.0 Geographic distribution: from the Barents Sea down to Geographic distribution: endemic to the Azores (Pico, Faial, Algarve (Portugal), the Mediterranean, the Azores (Flores), Flores, Sao Miguel and Formigas islets). Madeira, Canary Islands, near Iceland, Greenland and the Remarks: specimens recorded by Hawkins et al. (1990: 27- eastern coast ofnorth America(Kaas & VAN Belle, 1985a). 28) and Azevedo (1991: 29) probably belong to this species but were not identified at species level. These specimens were Family Ischnochitonidae not present in the DBUA collection and could not be examined Callochiton septemvalvis (Montagu, 1803) by us. Callochiton achatinus (Brown, 1827). Urzelina bay, under stones (Morton, 1967: 36). Family Acanthochitonidae Bathymetry: from subtidal to 500 m depth (Kaas & Van Acanthochitona discrepans (Brown, 1827) Belle, 1985b). Anisochiton discrepans Brown, 1827. Azores (Mac Andrew, Dimensions: length = up to 22 mm; dorsal elevation = 0.35 to 1856: 145). SaoMiguel (Dautzenberg, 1889: 72). 0.46 (Kaas & Van Belle, 1985b). Chiton discrepans (Brown, 1827). Sao Miguel (Ponta Delgada) Geographic distribution: all Atlantic coasts of Europe, from (Nobre, 1924: 84; 1930: 61). Scandinavia and British isles, south to the Canary Islands. Also Bathymetry: from the intertidal zone down to 40 m depth. It in theMediterranean Sea (Kaas& Van Belle, 1985b). lives mainly on stones covered with algae in muddy zones (Macedo 1999). mm hepidochitonapiceola (Shuttleworth, 1853) Dimensions: length = 25-30 (Macedoetal., 1999). Lepidochitonapiceola (Shuttleworth, 1853). Sao Miguel (intertidal Geographic distribution: British isles, French Atlantic coast zone) (Kaas & Van Belle, 1981: 23; 1985b: 89-91). (Kaas, 1985) and the Azores (?). Dimensions: length =10 mm; breadth = 6 mm; dorsal eleva- Remarks: this is a dubious record. The specimens from Mac tion = 0.31 (Kaas & Van Belle, 1985b). Andrew, Dautzenberg and Nobre are to be examined (Strack, Geographic distribution: Canary Islands and the Azores (Kaas in litt.). So far, the occurrence of this species in the Azores & Van Belle, 1985b). remains highly questionable. hepidochitona simrothi(Thiele, 1902) Acanthochitonafascictdaris (Linnaeus, 1767) Lepidochitona simrothi (Thiele, 1902). Azores (Van Belle, 1984: Anisochitonfascicularis Linnaeus, 1766. Azores (Mac Andrew, 224-226). Flores, Faial, Terceira, Santa Maria and Sao Miguel 1856: 145). (Kaas & Van Belle, 1981: 27-29; 1985b: 93-95). Sao Miguel Acanthochitesadansoni de Rochebrune, 1881. Faial (Horta, -20m) (Bullock, 1995: 16). Azores (Mortone/¿7/., 1998: 57). and Flores (SantaCruz, -40m) (DAUTZENBERG, 1927: 232). Lepidochitona sp. Azores (MACEDO t?/., 1998: 75). Acanthochitona communis (Risso, 1826). Azores (VAN Belle, Material examined: DBUA 190, 191, 193, 524, 554 and 562 — 1984: 227). Flores (all intertidal zone); DBUA 337 - Formigas islets (interti- Acanthochitonafascicularis (Linnaeus, 1767). Sao Jorge (Urzelina dal zone); DBUA 457, 458, 459, 465, 475, 662 - Pico (0 to 3 m bay) (Morton, 1967: 36). depth); DBUA 625, 715, 732, 740, 741, 743, 744, 745, 746, Material examined: DBUA 176, 637, 683, 700, 719, 721, 730, 747, 785, 793 -SaoMiguel (intertidal zonedown to 14 m depth). 731 732, 733, 748, 751, 752, 767, 794 - Sao Miguel (interti- , Bathymetry: littoral and sublittoral (up to 14 m depth). dal zone down to 20 m depth); DBUA 240, 569, 574, 577, 799 Dimensions: length = 5-8 mm; breadth = 3-4 mm; dorsal ele- — Flores (intertidal zone down to 20 m depth); DBUA 410, vation = 0 37 433 801 —Faial (10 m down to 23 m depth); DBUA 486, 667, . . , >42< . , Theshallow-waterPolyplacophoraoftheAzoresandsomecommentsonthebiogeographicalrelationshipsoftheAzoreanmalacofauna 671, 726, 800 - Pico (intertidal zone down to 15 m depth). REFERENCES Bathymetry: from the intertidal zone down to 50 m depth (VAN Avila,S, P., 2000. Shallow-watermarine molluscsottheAzores: biogeographi- cal relationships. Arqnipétagu Life and marine Sciences. Supplement 2 Belle, 1984). (PartA), Morta: 99-l.M. Dimensions: length = 26 mm; breadth = 16 mm. Colour: extremely variable (black, olive, orange, whitish). Azevedo,J. M. N., 1991. Estudodascmmmtdadesmalacológicasfitaisdahturalem SailMiguel, Apires, ProvasdeA.P.C.C.. UniversidadedosAzores,Punta Geographic distribution: Brittany (France) and southern Delgada,IV+75pp. England to Madeira, Canary Islands, in the whole Mediterra- Bullock, R. C., 1995. Thedistribution ofthe molluscan launaassociated with nean Sea (Kaas, 1985) and the Azores (Pico, Faial, Sao Jorge, the intertidalcorallinealgal turfofapartiallysubmergedvolcaniccra- Flores and Sao Miguel). ter,theIlheudeVilaFranca,SaoMiguel,Azores. InMartins,A. M. de F. (ed), The marine faunaand floraot the Azores. Proceedings ot the DISCUSSION Second International Workshop ot Malacology and Marine Biology, Vila Franca do Campo, Sao Miguel, Azores. Apireana, Suplemento The publication ot ÁVILA (2000) on the biogeographical rela- Maiode 1995: 9-55. tionships ol the Azorean shallow-water marine molluscs did not CLEMAM. CheckListot EuropeanMarineMollusca. UiiitasMalacnlogtea Inter- include the Polyplacophora. That paper dealt with the Gastro- net Resources for Malacologists (http://www.mnhn.fr/ poda, Bivalvia and Cephalopoda, ofwhich 231 taxa were confir- base.malaco.html). med from the Azores. Adding now the 5 species ol Polypla- Dautzenberg, P., 1889. Contribution àla taune malacologiquedes lies Azores. cophora reported from the Azores, the results are, as expected, RésultatsdesdragageseffectuésparleyachtXHinmdellependantsacam- very similar. The biogeographic region with higher number ol pagnescientifiquede 1887. RevisiondesmolltisquesmarinsdesAzores. RésultatsdesCampagnesSáentifiquesduPrincedeMnnaco 1,112pp.,4pls.. shared species to the Azores is still the western Mediterranean (184 out of 236 or 78.0%), lollowed by Madeira (63.1%), the Dautzenberg, P., 1927. Mollusquesprovenantdescampagnesscientifiquesdu mainland ofPortugal (62.3%) and the Canary Islands (59-7%). PrinceAlbert terdeMonacodans l'Océan Atlantiqueet dans leGolfe de Gascogne. Résultats des campagnessaentifiques accompliés sursnnyacht Only about 5% of the Azorean species occur at Ascension and parAlbertler. 72,400pp.,pls. 1-9. Saint Flelena islands, whereas there are 23 species that are also Hawkins, S.J., L. P. Burnay, A. I. Neto, R. Tristào da Cunha & A. M. F. reported to the eastern coast ofnorth America (Table 2). Martins, 1990. A description ot the zonation patterns ot molluscs These results corroborate those ofAvila (2000) who demon- andotherimportantbiotaon thesouthcoastotSaoMiguel,Azores. In strated a greater similarity ol the Azorean malacolauna with the Martins, A. M. de F. (ed). The marine tauna and flora ofthe Azores. Proceedings ot the First International Workshop ot Malacology Sao eastern Atlantic than with the western Atlantic, despite ol the Miguel,Azores.Apreana,SuplementoOutubrode 1990: 21-38. prevailing sea-surface currents Irom west to the east. Kaas, P., 1985. ThegenusAcanthochitunaGray, 1821 (Mollusca, Polyplacopho- ACKNOWLEDGEMENTS ra) in the north-eastern AtlanticOcean and in the Mediterranean Sea, withdesignationofneotypesotA.fasaculais (L., 1767)andofA. crini- MalcomJones’s suggestions and criticisms improved the cla- ta (Pennant, 1777). Bull. AI//.Í. natn. Hist., Paris, 4e. sér., 7, section A rity of an earlier version ol the manuscript. The comments ol 3: 579-609. Hermann Strack were crucial in relevant parts ol this paper. We Kaas, p. & R. AVan Belle, 1981. ThegenusLepidnchitunaGray, 1821 (Mollu- also thank Peter Wirtz, fordonating specimens ofA.fasciailaris. sca: Polyplacophora) in the northeastern AtlanticOcean, the Mediter- This study was supported by grant JNICT (PRAXIS ranean Sea and the Black Sea. Zmilogische Verhandelingen 185: 1-43, figs. 1-128. XXI/BIC/2788/96) and by PRAXIS/2/2.l/BIA/169/94. The fir- st author was supported by grant PRAXIS XXI/BIC/2788/96. Kaas, p. & R. A Van Belle, 1985a. Monograph oflivingchitons {Mollusca: Poly- placnphora).Voi. 1. E.J. Brill Publishers,Leiden, 1: 24(1pp. Table 2: Number and percentage ofshared species between the malacofauna of a given region and the Azores (236 confirmed taxa). ASC—Ascension Island; STH —Saint Helen Island; remaining abbreviations as in Table 1 AZO % shared species SCA 80 33.9 BRI 115 48.7 POR 147 62.3 MED 184 78.0 MAD 149 63.1 CAN 141 59.7 ASC 13 5.5 STH 12 5.1 AME 23 9.7 >43< SérgioP.Ávila&AndréAlbergarla Kaas,p.&R. aVanBelle, 1985b.Monographoflivingchitons(Mollusca:Polypla- cophora).Voi. 2.E.J. BrillPublishers,Leiden,2: 198pp. Kaas, p. c& R. AVanBelle, 1987. Monographoflivingchitons(Mollusca:Polypla- cophora).Voi. 3.E.J. BrillPublishers,Leiden,3: 302pp. Kaas, p. & P AVanBelle, 1990. Monographoflivingchitons(Mollusca:Polypla- ccphora).Voi. 4. E.J. BrillPublishers,Leiden,4: 298pp. Kaas, ,. &R. AVanBelle, 1994. Monographoflivingchitons(Mollusca:Polypla- cophora}.Vol. 5.E.J. BrillPublishers,Leiden,5:402pp. Mac Andrew, R., 1856. Report on the marine testaceous Mollusca ofthe North-EastAtlanticandneighbouringSeasandthephysicalconditions affecting theirdevelopment. ReportoftheBrit. Assoc,fortheAdv. ofSc., London, 158pp. Macedo,M.C. C.,Macedo,M. I. C. &J. P. Borges, 1999.ConchasMarinhasde Portugal. EditorialVerbo,Lisboa, 516pp. Morton,B., 1967. Malacological Report. ChelseaCollegeAzoresExpedition,July- October1965. FinalReport: 30-38. Morton,B.,J.C. Britton&A.M. F.Martins, 1998. EcologiaCostaradosAyo- res.SociedadeAfonsoChaves,PontaDelgada,X+249pp. Nobre, A. 1924. Contribui^oes para a fauna dos Agotes. An. Inst. Zool. Univ, Porto, 1:41-90. Nobre,A., 1930.MateriaisparaoestadodafaunadosAyores. InstitutodeZoologia daUniversidadedoPorto,Porto, 108pp. Van Belle, R. A., 1984. De Polyplacophora van de Azoren. Gloria Maris, 23(10): 223-230. LavoroaccettatoII9Settembre2001 >44<