Waipatia maerewhenua^ New Genus and New Species (Waipatiidae, New Family), an Archaic Late Oligocene Dolphin (Cetacea: Odontoceti: Platanistoidea) from New Zealand R. Ewan Fordyce Department of Geology, University of Otago, P.O. Box 56. Dunedin, New Zealand ABSTRACT.— Waipatia maerewhenua, from the Otekaike Limestone (late Oligocene). Waitaki Valley. New Zealand, is a new genus and skull 600 species in a new family Waipatiidae (Odontoceti: Platanistoidea) near the base of the radiation of platanistoids. Its features include about mm long; rostrum long and narrow; incisors long, procumbent, and gracile; cheek teeth heterodont and polydont: maxillae telescoped back over frontals toward supraoccipital; parietal narrowly exposed on vertex; pterygoid sinus fossa restricted to basicranium; and palatine broad and not invaded by pterygoid sinus fossa. Features of the tympano-periotic, periotic fossa, and foramen spinosum indicate platanistoid relationships. Waipatia maerewhenua is more closely related to the Squalodelphidae and Platanistidae than to the Squalodontidae. Of the similar small dolphins previously identified as Squalodontidae. Mierocetus ambiguus ( late Oligocene. Germany ) and Sachalinocetus cholmicus (early or middle Miocene. Sakhalin) are possible waipatiids. Mierocetus hectori (earliest Miocene. New Zealand! is a probable squalodelphid. Prosqualodon marplesi (early Miocene. New Zealand) is transferred to Notocetus (Squalodelphidae) as Notocetus marplesi (new combination). Sulakocetus dagestanicus (late Oligocene, Caucasus) is probably a waipatiid close to W. maerewhenua. These taxa reveal an early radiation of the Platanistoidea by the late Oligocene. INTRODUCTION biology, National Museum of Natural History, Smithsonian Institu- tion. Washington, D.C. This article describes a new family, new genus, and new species from New Zealand. of late Oligocene marine platanistoid dolphin SYSTEMATICS Heterodont dolphins from Oligocene and Miocene rocks world- wide have a role in of cetacean evolution played key interpretations Order Cetacea Brisson, 1762 because they are transitional in grade between archaic Cetacea (Archaeoceti) and extant odontocetes. Waipatia maerewhenua Suborder Odontoceti Flower. 1867 meets traditional concepts of the Squalodontidae, a family often used for heterodont odontocetes. but is more closely related to the Superfamily Platanistoidea Simpson. 1945 Squalodelphidae and Platanistidae than to the Squalodontidae. It is Family new an early member of the platanistoid radiation that led to diverse Waipatiidae, Miocene taxa and ultimately to the two extant species of "river Type genus. — Waipatia, new genus. dolphins" of the genus Platanista; the latter represent the last of the Included genera. — Waipatia, new genus, only. Platanistidae and, probably, the superfamily Platanistoidea. Diagnosis of family. —As for the only included species, Waipatia maerewhenua thus has implications for odontocete his- Waipatia maerewhenua. in the only included genus, Waipatia, be- tory and for defining and delimiting the Squalodontidae. Squalodel- low. phidae, and Platanistoidea. Comment. —The family probably includes Sulakocetus 1 a The article has three main sections: ( ) description reviewing dagestanicus Mchedlidze, 1976 (late Oligocene, Caucasus), and morphology and commenting on other taxa as needed to help may include species of Mierocetus and Sachalinocetus; these are interpret homology, (2) a comparison covering broader aspects of discussed below. morphology, homology, and function, and (3) cladistic relation- A new combination, Notocetus marplesi (Dickson. 1964) ships. Genus Waipatia, new (Platanistoidea: Squalodelphidae). is used throughout for the so- of Zealand. called Prosqualodon marplesi New Type species. — Waipatia maerewhenua, new species. Included species. — Waipatia maerewhenua. new species, only. — As for the included maere- MATERIAL AND METHODS Diagnosis. only species. Waipatia whenua, below. Etymology. —From the Maori name Waipati. a place near the are based on the or left side, whichever is Descriptions right Re- type locality. Probable derivation: wai, water; pati, shallow. more informative, with differences between right and left men- garded as indeclinable. Pronunciation: wai-pa-ti. with a pronounced tioned only if asymmetry is evident. Unreferenced statements about as in English "far," and /' as in "he." morphology are based on personal observations. The specimen was with chisels and Fine details were prepared pneumatic scrapers. Waipatia maerewhenua, new species prepared under a microscope with an ultrasonic dental scaler and an sutures not be traced because the air-abrasive unit; some could fully Figs. 2-8. 9b, lOa-k, 11,12, 13a-g cancellous bone is friable and not permineralized. Photographs were taken with a 35-mm Asahi Pentax camera with a 50-mm Material.—Holotype only, OU 22095: a skull with 23 teeth in macro lens. Illustrations derived from photographs are not cor- place, both mandibles. 17 loose teeth, left tympanic bulla, right anterior natural cast of rected for parallax. periotic. left periotic lacking process, atlas, Acronyms used here are NMNZ Ma. marine mammal catalog in anterior of axis, and anterior thoracic vertebra. Collected by R. the National Museum of New Zealand, Wellington, New Zealand; Ewan Fordyce. A. Grebneff, and R. D. Connell. January 1991. 5 OM C and OM A, catalogs in Otago Museum, Dunedin, New Type locality. —North-facing cliff near Waipati Creek, km north of Earth- Zealand; OU, fossil catalog in Geology Museum, University of west-southwest of Duntroon and 1.2 km "The Otago, Dunedin, New Zealand; USNM, Department of Paleo- quakes," North Otago (Fig. 1). Grid reference: NZMS [New In A. Berta and T. A. Demere (eds.) Contributions in Marine Mammal Paleontology Honoring Frank C. Whitmore, Jr. Proc. San Diego Soc. Nat. Hist. 29:147-176. 1994 148 R. Ewan Fordyce not seen NZ slag top massive limestone with 30 J iiirrrj sparse brachiopods ^iii poorly exposed i i i , , J=feriii Wi cliff top 20:: iiirff massive limestone with i5S occasional macrofossils i i i i rrii i massive limestone I : Igl glauconitic 10 grades up 0^ bedded with greensand abundant macrofossils " 3 3 9 a massive bioturbaled 9- 9 :9 i muddy 3':3: : S:3. greensand with reworked clasls 9:'9g'3.9'3.'9 °! calra reou s mu dstone •^—extensively bored massive calcareous mudstone base not seen "The Earthquakes" 149 Waipatia maerewhenua. New Genus and New Species, an Archaic Late Oligocene Dolphin from New Zealand nation. Here, the lower Otekaike Limestone represents the a narrow band of parietals exposed dorsally. The supraoccipital lies Duntroonian Stage (late to latest Oligocene), while Waitakian fau- well forward, not encroached upon by facial elements. nas (earliest Miocene) appear 13-14 m above the base of the Rostrum. —The rostrum is relatively long, w ide at its base at the limestone. antorbital notches, and attenuated anteriorly (Figs. 2a, 3a). Each Diagnosis. —Odontocete with slightly asymmetrical skull of antorbital notch, which transmitted the facial nerve, is open anteri- medium size (condylobasal length approximately 600 mm), attenu- orly but is shallow dorsoventrally. A prominent antorbital (preor- ated rostrum, heterodont polydont teeth, and basicranium of archaic bital) process extends forward to bound the notch laterally. Anterior of the maxilla flares out to form grade. Placed in the Platanistoidea because the periotic has an to the right notch, the rostral margin is a the left The notch incipient articular process, the anterior process roughly cylindri- marked flange missing on (Figs 2a, 4a. 5a). right cal in cross section and deflected ventrally. and the tympanic bulla is deeper and more U-shaped than the left. As viewed laterally (Fig. the ventral has an incipient anterior spine, anterolateral convexity, and ventral 2c). the premaxilla forms all of the dorsal profile; groove extending anteriorly as a series of long fissures. Allied with surface of the rostrum, formed by the maxilla, is roughly flat, and the Squalodelphidae and Platanistidae, rather than the Squalodonti- the rostrum thins only a little apically. In ventral view (Fig. 2c), the dae, because the long asymmetrical posterior apex of the premaxilla anterior half of the rostrum is grooved medially, while posteriorly it are no extends posterior to the nasal to wedge between the elevated edge is gently convex. Palatal ridges are indistinct, and there of the maxilla and frontal on vertex, the cheek teeth are small, the rostral fossae for pterygoid sinuses. In dorsal view, the open incisors are relatively delicate and procumbent, the premaxillary mesorostral groove is wide posteriorly but narrow anteriorly. Other 4 sac fossa is relatively wide and expanded medially to form a signifi- profiles of the rostrum are shown in Figs. 2 and — is in dorsal cant prenarial constriction, the pterygoid sinus fossa is in the Premaxilla. Anteriorly, the premaxilla narrowest it the alisphenoid and/or basioccipital dorsolateral to the basioccipital view at mid-rostrum, where bounds and slightly roofs crest and posteromedial to the foramen ovale, the lateral groove mesorostral groove. Further forward, the premaxilla forms the api- affects the external profile of the periotic. rendering it sigmoidal in cal 55+ mm of the rostrum. The dorsal rostral suture with the dorsal view, the dorsal ridge on the anterior process and body of the maxilla is prominent but not deep. The premaxilla forms an for the internarial constriction where the sac fossa periotic is