BULLETIN DE L'INSTITUT ROYAL DES SCIENCES NATURELLES DE BELGIQUE, BIOLOGIE, 59: 101-157, 1989 BULLETIN VAN HET KONINKLIJK BELGISCH INSTITUUT VOOR NATUURWETENSCHAPPEN, BIOLOGIE, 59: 101-157, 1989 Contributions to the study of the comparative morphology of teeth and other relevant ichthyodorulites in living supraspecific taxa of Chondrichtyan fishes Editor : M. STEHMANN Part A: Selachii. No.3: Order: Squaliformes Families: Echinorhinidae, Oxy:riotidae and Squalidae by J. HERMAN, M. HOVESTADT-EULER and D.C. HOVESTADT Abstract Erlaubt eine direkte generische Zuordnung und einige taxonomische Anpassungsvorschliige. Die Ergebnisse stiitzen Auffassungen friiherer Autoren, dass die Echinorhinidae eine eigene Ordnung darstellen ; die The teeth of nearly all supraspecific taxa of squaliformes are described Oxynotidae odontologisch mit den Squalidae ubereinstimmen ; die and illustrated by SEM photos. The tooth morphology allows a direct Squalidae-Gattungen in 8 Unterfamilien gruppiert werden Konnten, assignment to all these taxa and some proposals of taxonomic von denen 4 bisher nicht definierbar waren; Centroselachus GARMAN, adjustments. 1913 findet sich bestiitigt und sollte wieder errichtet werden ; odontolo­ The results support opinions of other authors, that Echinorhinidae gisch finden sich keine signiftkanten Unterschiede zwischen Cirrhigaleus represent a separate order, Oxynotidae coincide odontologically with und Squalus, Lepidorhinus und Centrophorus, Scymnodon und Squalidae ; Squalid genera could be grouped into 8 subfamilies, 4 of Scymnodalatias, ebensowenig Squaliolus sowie Heteroscymnoides which could not be defined hitherto; Centroselachus GARMAN, 1913 is einerseits und Euprotomicrus anderseits ; den 3 Somniosus-Arten confirmed and should be revalidated ; significant odontological waren 2 Untergattungen zuzuordnen : Somniosus (Somniosus) und differences do not exist between Cirrhigaleus and Squalus, Lepidorhinus Somniosus (Rhinoscymnus). Ein morphologischer Schliissel zur gene­ and Centrophorus, Scymnodon and Scymnodalatias, neither between rischen Bestimmung wird gegeben. Squaliolus and Heteroscymnoides and Euprotomicrus on the other Schliisselworter: Elasmobranchii- Selachii- Squaliformes- Echinorhi­ hand; 2 subgenera appear to be justified for the 3 species of Somniosus : nidae - Oxynotidae - Squalidae - Odontologie. Somniosus (Somniosus) and Somniosus (Rhinoscymnus). An odontological key is given for all these supraspecific taxa. Introduction Key-words: Elasmobranchii- Selachii- Squaliformes -Echinorhinidae - Squalidae- Odontology. Major revisions of shark systematics and squaloids in Resume particular were published by Bigelow & Schroeder (1957), Bass, d'Aubrey and Kistnasamy (1976) and Les dents de Ia plupart des taxons supraspecifiques des squaliformes Compagno (1973, 1977 and 1984). sont decrites et figurees (cliches MEB). La morpho Iogie dentaire permet The teeth of Squaliformes were the subject of a study to une identification generique ou subgenerique ainsi que Ia formulation compare fossil teeth by Ledoux (1970, 1972), who d'un certain nombre de propositions de reajustements taxonomiques. described and figured several genera, as well as Casier Dans !'ensemble, ces resultats concordent avec !'opinion d'autres chercheurs. (1961). Ainsi, les Echinorhinidae representeraient un ordre distinct ; les Also Welton (1973) described and figured several Oxynotidae ne se distinguent odontologiquement pas des Squalidae. genera in an unpublished thesis. Les divers genres de Squalidae pourraient etre regroupes en 8 sous­ In this fascicle, will be described and illustrated the familles, dont 4 non encore definies. Centroselachus GARMAN, 1913 est revalidable. II n'existe aucune teeth of all living squaliform families and genera difference odontologique significative entre Cirrhigaleus et Squalus, belonging to this order, with the exception of Mollis­ Lepidorhinus et Centrophorus, Scymnodalatias et Scymnodon, pas quama parini DOLGANOV, 1984, which was not avai­ plus qu'entre Squaliolus, Heteroscymnoides et Euprotomicrus. lable for examination. Les 3 especes de Somniosus peuvent etre reparties au sein de 2 sous­ genres: Somniosus (Somniosus) et Somniosus (Rhinoscymnus). Also Zameus squamulosus, a genus which is in discus­ Une cle odontologique est proposee pour Ia distinction de tous ces sion (Taniuchi & Garrick, 1986), was not available for taxons. examination. Mots-clefs : Elasmobranchii- Selachii- Squaliformes- Echinorhinidae - Oxynotidae - Squalidae - Odontologie. The ordering of genera and species is according to the grouping of taxa based on the present result. Kurzfassung The nomenclature of taxa is according to Compagno ( 1984). The original literature reference of each specific Die Kieferziihne fast aller squaliformen supraspezifischen Taxa werden taxon will be given in the descriptive part, respectively beschrieben und mit REMPhotos illustriert. and not be repeated in the bibliography. 102 J. HERMAN, M. HOVESTAD-EULER and D.C. HOVESTADT Systematics and materials The following 904 specimens belonging to 48 species were examined : 1 female ORDER: SQUALIFORMES, Aculeola nigra 3 males sensu COMPAGNO (1984) Centrophorus acus 1 male Centrophorus granulosus 18 males 28 females Centrophorus lusitanicus 2 females This order comprises the families Echinorhinidae, Centrophorus uyato 3 males 1 female Oxynotidae and Squalidae, which will be described Centrophorus squamosus 15 males 47 females and illustrated in detail below. Centroscyllium fabricii 4 males 51 females With the addition of Mollisquama parini DOLGANOV, Centroscyllium granulosum 18 males 24 females 1984, that was not yet included, these families comprise Centroscyllium nigrum 3 males 3 females the following genera : Centroscyllium ritteri I male Family : ECHINORHINIDAE GILL, 1872 Centroscymnus coelolepis 47 males 47 females Genus : Echinorhinus BLAINVILLE, I816 Centroscymnus crepidater 25 males 48 females type species : Echinorhinus brucus Centroscymnus owstoni I female Cirrhigaleus barbifer 1 female Dalatias licha 22 males 40 females Family: 0XYNOTIDAE Deania calcea 48 males 45 females Genus: Oxynotus RAFINESQUE, I810 Deania histricosa 1 male 1 female type species: Oxynotus centt·ina Deania profundorum 2 males 6 females Echinorhinus bntcus 2 males 3 females Family: SQUALIDAE BLAINVILLE, I816 Echinorhinus cookei 2 males 1 female Genus: Aculeola DE BUEN, 1959 Etmopterus bullisi 1 male 2 females type species : Aculeola nigra Etmopterus hillianus 6 males 12 females Genus: Centrophorus MULLER & HENLE, I837 Etmopterus lucifer 2 males 2 females type species : Centrophorus granulosus Etmoptems polli 1 male 2 females Genus: Centroscyllium MULLER & HENLE, 1841 Etmopterus princeps 5 males 4 females type species : Centroscylliumfabricii Etmopterus pusillus 2 males 3 females Genus: Centroscymnus BOCAGE & CAPELLO, 1864 Etmopterus schultzi 3 males I female type species : Centroscymnus coelolepis Etmopterus spinax 45 males 61 females Genus: Cirrhigaleus TANAKA, 1912 Etmopterus virens 2 females type species : Cirrhigaleus barbifer Euprotomicroides zantedeschia 1 male 1 female Genus: Dalatias RAFINESQUE, I810 Euprotomicrus bispinatus 1 male 2 females type species : Dalatias licha Heteroscymnoides marleyi 1 female Genus : Deania JORDAN & SNYDER, 1902 Isistius brasiliensis I male 3 females type species : Deania calcea Oxynotus bmniensis l male Genus: Etmopterus RAFINESQUE, 1810 Oxynotus caribbaeus 1 male type species : Etmoptems spinax Oxynotus cenu·ina 13 males I6 females Genus: Euprotomicroides HULLEY & PEN RITH , 1966 Oxynotus paradoxus 4 males 2 females type species : Euprotomicroides zantedeschia Scymnodalatias albicauda 1 female Genus : Euprotomicrus GILL, 1864 Scymnodon obscurus 2 males 2 females type species : Euprotomicrus bispinatus Scymnodon ringens 18 males 30 females Genus : Heteroscymnoides FOWLER, 1934 Somniosus microcephalus 7 males 18 females type species : Heteroscymnoides marleyi Somniosus pacificus 1 male 2 females Genus: lsistius GILL, 1864 Somniosus rostratus 1 male 4 females type species : Isistius brasiliensis Squaliolus laticaudus l male 4 females Gensu: Mollisquama DoLGANOV, I984 Squalus acanthias 36 males 45 females type species : Mollisquama parini Squalus asper 1 female Genus : Scymnodalatias GARRICK, 1956 Squalus blainvillei 4 males 18 females type species : Scymnodalatias sherwoodi Squalus cubensis 1 male Genus : Scymnodon BOCAGE & CAPELLO, 1864 type species : Scymnodon ringens There is a remarkable morphological difference in Gensu: Somniosus LESUEUR , 181 8 tooth arrangement between Echinorhinidae, Oxynoti­ type species : Somniosus microcephalus dae and Squalidae. The lower tooth ftles are very Genus: Squaliolus SMITH & RADCLIFFE, 1912 compressed in Oxynotidae and Squalidae (with the type species : Squaliolus laticaudus exception of the genera Centroscyllium and Aculeola) , Genus : Squalus LINNAEUS, 1758 resulting in interlocking of the teeth. This interlocking type species : Squalus acanthias is demonstrated by positioning the outer mesial part of I' Contributions to the study of the comparative morphology of teeth and other relevant ichtyodorulites 103 each tooth behind the inner distal part of the previous Scymnodon ringens 24125 14115 tooth. This phenomenon is even present in both upper Somniosus microcephalus 20124 24/ 29 and lower jaws in some genera of the Squalidae. These Somniosus rostratus 30 161 18 teeth have therefore a particular depression on outer Squaliolus laticaudus 10111 9 mesial and inner distal part of the root. Interlocking is
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