A potentional phylogenetic lineages of †Cretolamna appendiculata Glückman, 1958 based on dental morphology

StES 7th Scientific Conference Students Encounter Science with international participation Banja Luka, 26.-28. November 2014.

A POTENTIONAL PHYLOGENETIC LINEAGES OF †Cretolamna appendiculata Glückman, 1958 BASED ON DENTAL MORPHOLOGY Andrej Gajić & Adla Kahrić Sharklab – Society for research and protection of the cartilaginous fish †Cretolamna is extinct genus of selachians that occured during the Cretaceous and Paleogene, exactly members of mentioned taxa lived in the period of 90 to 50 million years ago. The culmination of developmant they reaches at thr Paleocene and Eocene, after wihch disappear. The fossilized remains of a given species are represented by teeth and the remains of the vertebrae. Tooth size, on average, varies from 10 to 20 mm, which assumed the total lenght from 200 to 300 cm, whith a maximum size up to 370 cm. Given taxon was widespread in today's North Africa (Morocco) and North America, mainly on the East Coast and Midwest. Comparative odontology studies discover the following pray of †Cretolamna: lagreg bonyfish, turtle,s mosasaur, squids and other sharks. Phylogenetic and comparative odontology studies in this paper were performed on teeth of following species: †Cretolamna appendiculata Gluckman, 1958 from Morocco, †Otodus obliquus (Agassiz, 1843) from Portugal and †Carcharocles megalodon (Agassiz, 1843) from Bosnia and Herzegovina; as well as other relevant taxa, together with consulting the available literature. According to the current evolutionary-taxonomic views †C. appendiculata is considered as a direct ancestor of Oligocene species †C. megalodon, although philogenesis itself is till not clarified. This paper presents the potential phylogenetic pathways of †C. appendiculata with emphasizing the incremental specific adaptive changes based on dental morphology, through certain intermedial forms. Presented study is one ot he basic steps in the current reseraches of phylogeny and evolution of the family †Otodontidae Gluckman, 1964 wihch appears in the Paleocene and became extinct in Pliocene.

†Cretolamna izumrli je genus selahija koje se pojavljuju tijekom Krede i izumiru u središnjem Paleogenu, tačnije živjele su u periodu prije 90 do 50 miliona godina. Vrhunac svoj razvoja dostižu u Paleocenu i Eocenu, nakon kojeg nestaju. Fosilizirani ostaci datih vrsta predstavljeni su zubima i ostacima kralježaka. Veličina zuba, u prosjeku, iznosi 10 do 20 mm, na osnovu čega se pretpostavlja ukupna dužina jedinki 200 do 300 cm, uz maksimalan rast do 370 cm. Dati takson bio je široko rasprostranjen u današnjoj Sjevernoj Africi (Maroko) i Sjevernoj Americi, pretežno na istočnoj obali. Komparativno odontološkim studijama utvrđen je i tipični plijen istraživanog roda: veće košljoribe, kornjače, mosasaurusi, lignje, kao i druge hrskavičaste ribe. Filogenetske i komparativno odontološke studije u ovom radu vršene su na uzorcima vrsta: †Cretolamna appendiculata Glückman, 1958 iz Maroka, †Otodus obliquus (Agassiz, 1843) iz Portugala i †Carcharocles megalodon (Agassiz, 1843) iz Bosne i Hercegovine; kao i druge relevantne taksone, zajedno sa konsultovanjem dostupne literature. Prema aktuelnim evoluciono-taksonomskim stajalištima, vrsta †C. appendiculata smatra se direktnim pretkom Oligocenske vrste †C. megalodon, iako sama filogeneza još uvijek nije razjašnjenja. U ovom radu navode se potencijalni filogenetički putevi †C. appendiculata uz naglašavanje postepenih specifičnih adaptivnih promjena baziranih na dentalnoj morfologiji, kroz određene intermedijalne oblike. Prezentiran studija predstavlja jedan od bazičnih koraka u trenutnom istraživanju filogeneze i evolucije porodice †Otodontidae Gluckman, 1964 koja se pojavljuje u Paleocenu, a izumire u Pliocenu.