Krister T. Smith

Helodermatid Lizard from the Miocene of Florida, the Evolution of the Dentary in Helodermatidae, and Comments on Dentary Morphology in Varanoidea

Abstract A helodermatid dentary and osteoderms from the Miocene Thomas Farm locality in Gilchrist County, Florida, demonstrate the broad historical distribution of Helodermatidae in North America during the Tertiary. A comparative approach, taking into account variation in extant Heloderma, reveals that the dentary is intermediate in several characters between the plesiomorphically long, low, mediolaterally narrow dentary of Eurheloderma gallicum and the taller, wider dentary of extant Heloderma. An eminence upon the intramandibular septum in the Thomas Farm helodermatid and some extant Varanoidea is part of a previously unrecognized anatomical structure, a foramen formed by dentary and postdentary elements and normally covered by the splenial. The teeth of the Florida helodermatid are intermediate between the more numerous, shorter teeth of E. gallicum and the fewer, taller teeth of extant Heloderma. Certain dental structures whose evolution is here elucidated are part of the novel helodermatid venom delivery system. The evolution of the dentary and teeth in Varanoidea as a whole is a more complex and informative story than was previously appreciated. No living varanoid displays unmodified the primitive varanoid conical tooth morphology. Extant Heloderma show a dentition modified in association with venom delivery, whereas Varanidae show labiolingual compression of the tooth crown. Varanus in particular is highly modified and should not be used as a proxy for the varanoid ancestor in studies of the dentigerous elements and dentition. The informativeness of isolated squamate dentaries is evidenced by the derivation of 15 new phylogenetic characters from the anatomy of helodermatid dentaries and dentition.

Variation in the Position of the Jugal Medial Ridge Among Lizards (Reptilia: Squamata): Its Functional and Taxonomic Significance

The course of the medial ridge in the lizard jugal shows considerable morphological variation. There are four basic configurations: (1) the medial ridge is located ventral to mid‐height on the suborbital process and anterior to mid‐length on the postorbital process; (2) the medial ridge is located ventrally on the suborbital process (as above), but posteriorly on the postorbital process; (3) the medial ridge is located dorsally on the suborbital process and anteriorly on the postorbital process; and (4) the medial ridge is centrally located along the entire length of the jugal. Ancestral character state reconstruction shows that type 1 is plesiomorphic for Squamata regardless of the broad‐scale phylogenetic topology. Type 3 is present in chamaeleonids and convergently in Anolis barbatus. Type 3 is a synapomorphy of the chamaeleonids. Type 2 is considered plesiomorphic for Anguidae, Heloderma and Xenosaurus, although it is independently modified in some extant members. These taxa form a clade in molecular phylogenies of Squamata, and the course of the medial ridge of the jugal therefore provides some measure of morphological support for this arrangement. The course of the medial ridge may be best explained by the position of the eye and by the angle of the jugal; its relations with other bony orbital structures (supraocular osteoderms, palpebral, supraorbital flanges) and the posterior extent of the maxilla are also discussed. Anat Rec, 297:2262–2272, 2014.

Bat remains (Mammalia, Chiroptera) from the Middle Pleistocene site of Qesem Cave, Israel, with the first Pleistocene record of fruit bats in the Mediterranean region

Very few data are available on fossil bats of the Near East, a region of great biogeographic significance for that group in the Western Palaearctic. Here, we report on a collection of fossil bats from the Middle Pleistocene site Qesem Cave, Israel, famous for lithic artifacts, hominin remains and rich vertebrate faunas. We identified five microchiropteran species, viz. Rhinolophus ferrumequinum, R. euryale, R. mehelyi, Miniopterus cf. schreibersii, and Myotis blythii, all typical cave-dwellers common also in extant communities in the region. Their appearance suggests mild conditions with variegated vegetation at the time of deposition. In addition, two tooth fragments, tentatively identified as cf. Rousettus sp., provide the first Pleistocene record of fruit bats beyond the tropics. If these remains pass muster, the Quaternary history of fruit bats in this region could be traced back to the Pleistocene, earlier than previously thought, and then the extant extralimital population of Rousettus aegyptiacus could be seen as a palaeochoric element of the Mediterranean biota. In general, the Pleistocene record of bats in the Levant (including Qesem) is characterized by the absence of the Ethiopian elements that dominate the extant Levantine fauna, while the vast majority of the fossil bat forms are elements of the Palaearctic clades. Ivan Horáček. Department of Zoology, Charles University, Vinicna 7, CZ 128 44 Praha, Czech Republic, ivan.horacek@natur.cuni.cz Lutz Christian Maul. Research Station of Quaternary Palaeontology, Senckenberg Research Institute and Natural History Museum, Am Jakobskirchhof 4, 99423 Weimar, Germany, lmaul@senckenberg.de K.T. Smith. Department of Palaeoanthropology and Messel Research, Senckenberg Research Institute and Natural History Museum, Senckenberganlage 25, 60325 Frankfurt, ksmith@senckenberg.de Ran Barkai. Department of Archaeology, Tel Aviv University, Ramat Aviv, Tel Aviv 69978, Israel, barkaran@post.tau.ac.il Avi Gopher. Department of Archaeology, Tel Aviv University, Ramat Aviv, Tel Aviv 69978, Israel, agopher@post.tau.ac.il HORÁČEK ET AL.: QESEM BATS 2

Eolacertidae: a new extinct clade of lizards from the Palaeogene; with comments on the origin of the dominant European reptile group – Lacertidae

Abstract We describe a new lizard taxon, Stefanikia siderea gen. et sp. nov., from the early-middle Eocene locality of Messel in Germany based on a nearly complete skeleton, which we studied using μCT methods. It shares many characters with the Eocene taxon Eolacerta, which is broadly distributed in the Eocene of central and Western Europe, but is much smaller and shows several important anatomical differences. The new discovery sheds light on the paleodiversity of these lizards in the Eocene of Europe, and the new family name Eolacertidae is proposed to encompass Eolacerta and Stefanikia. The relationships of Eolacerta have been intractable. Our phylogenetic analyses confirm that Eolacertidae is a member of the clade Lacertiformes and provide strong support for a sister-group relationship to Lacertidae. In some places, skin impressions are preserved, displaying the body scalation. As such, the exquisitely preserved specimens of Eolacertidae from Messel provide new insight into the morphology and ecology of lizards on the stem of Lacertidae, Europe’s dominant group of living reptiles. http://zoobank.org/urn:lsid:zoobank.org:pub:DFD01563-A913-4286-B64B-E0912474FD08

The Only Known Jawed Vertebrate with Four Eyes and the Bauplan of the Pineal Complex

The pineal and parapineal organs are dorsal outpocketings of the vertebrate diencephalon that play key roles in orientation and in circadian and annual cycles. Lampreys are four eyed in that both the pineal and parapineal form eyelike photosensory structures, but the pineal is the dominant or sole median photosensory structure in most lower vertebrate clades. The pineal complex has been thought to evolve in a single direction by losing photosensory and augmenting secretory function in the transitions from three-eyed lower vertebrates to two-eyed mammals and archosaurs [1-3]. Yet the widely accepted elaboration of the parapineal instead of the pineal as the primary median photosensory organ [4] in Lepidosauria (lizards, snakes, and tuataras) hints at a more complex evolutionary history. Here we present evidence that a fourth eye re-evolved from the pineal organ at least once within vertebrates, specifically in an extinct monitor lizard, Saniwa ensidens, in which pineal and parapineal eyes were present simultaneously. The tandem midline location of these structures confirms in a striking fashion the proposed homology of the parietal eye with the parapineal organ and refutes the classical model of pineal bilaterality. It furthermore raises questions about the evolution and functional interpretation of the median photosensory organ in other tetrapod clades.