The early Tertiary (Paleocene and Eocene) family Presbyornithidae is one of the most completely known group of fossil birds. Essentially all parts of the skeleton are represented in the fossil record, allowing a thorough analysis of the phylogenetic position of the family. Forty-two families of nonpasserine birds representing the orders Ciconiiformes, Anseriformes, Galliformes, Gruiformes and Charadriiformes, were included in a cladistic analysis of 71 skeletal characters. The previously suggested anseriform affinity of the Presbyornithidae was confirmed. Furthermore, the family proved to be closer to the Anatidae than to the Anhimidae or Anseranatidae. The many postcranial similarities with certain charadriiform birds as the Burhinidae, obviously are plesiomorphies. By this observation, a better undestanding of character evolution in nonpasserine skeletal morphology is gained. The often suggested close relationship of anseriform and galliform birds is not confirmed by osteology. Instead, the Anseriformes and the Phoenicopteridae form a monophyletic clade that is the sister to the remaining ciconiiform birds. This result renders the Ciconiiformes sensu Wetmore (1960) polyphyletic. (C) 1997 The Linnean Society of London.
Biogeographical history and taxonomic delimitation in the Australo-Papuan bird-of-paradise Lophorina-Ptiloris species complex is examined with a combination of DNA and morphological markers. The results suggest that the complex started to diverge in the mid-Pliocene, driven by initial isolation and adaptation to altitudinally different habitats. As in many other New Guinean avian taxa, phylogeographic structure is more varied in montane Lophorina than foothill Ptiloris. With the exception of populations of Lophorina in the eastern New Guinean cordillera, phylogenetic patterns from molecular data and morphological discontinuities are consistently concordant, as are molecular species delimitation tests with previous morphology-based circumscription of taxa in Ptiloris. In Lophorina, however, both molecular data and significant, re-discovered morphological traits identify several taxa as more deeply differentiated than hitherto thought. Accordingly, we use these data in an integrative taxonomic approach to re-delimit taxa in the entire clade, including the recognition of three species in the previously monospecific Lophorina. In Lophorina, the identity of several type specimens is reviewed, one new subspecies is described from the Vogelkop, and the identity of the species name superba Pennant is resolved by neotypification, with correction of its author.
The Xenarthra, particularly the Tardigrada, are with the Notoungulata and Marsupialia among the most diversified South American mammals. Lujanian South American Land Mammal Age localities from the coastal Piedra Escrita site and Andean Casa del Diablo Cave, Peru, have yielded three specimens of the Megalonychidae Diabolotherium nordenskioldi gen. nov. This singular fossil sloth exhibits a peculiar mosaic of cranial and postcranial characters. Some are considered convergent with those of other sloths (e.g. 5/4 quadrangular teeth, characteristic of Megatheriidae), whereas others clearly indicate climbing capabilities distinct from the suspensory mode of extant sloths. The arboreal mode of life of D. nordenskioldi is suggested by considerable mobility of the elbow, hip, and ankle joints, a posteriorly convex ulna with an olecranon shorter than in fossorial taxa, a radial notch that faces more anteriorly than in other fossil sloths and forms an obtuse angle with the coronoid process (which increases the range of pronation– supination), a proximodistally compressed scaphoid, and a wide range of digital flexion. D. nordenskioldi underscores the great adaptability of Tardigrada: an arboreally adapted form is now added to the already known terrestrial, subarboreal, and aquatic (marine and freshwater) fossil sloths. A preliminary phylogenetic analysis of the Tardigrada confirmed the monophyly of Megatherioidea, Nothrotheriidae, Megatheriidae, and Megalonychidae, in which Diabolotherium is strongly nested.
Ribbon worms (phylum Nemertea) have traditionally been described and classified based on a combination of internal and external morphological characters. The extent, and wealth of details, of these descriptions vary both over time and amongst authors. In addition, definitions of characters and character states are in many cases vague, causing problems both for identification and in phylogenetic analyses. Here, we suggest a system of describing nemerteans based on a list of characters and their states with the actual description in the form of a vector of character state symbols. We argue that this system makes it easier for other systematists to extract the necessary characters/character states for comparative and phylogenetic analyses. The proposed list of characters can also act as a checklist for nemertean description, whereby hopefully ambiguities (such as does the nonmentioning of a character actually mean ‘missing’ or just not looked for) can be avoided in the future. We describe two new species and one new genus Carinina ochracea sp. nov. and Raygibsonia bergi gen. et sp. nov. using this concept in combination with molecular analyses based on 18S and cytochrome oxidase I (COI) DNA sequences.
Mobergellans were one of the first Cambrian skeletal groups to be recognized yet have long remained one of the mostproblematic in terms of biological function and affinity. Characterized by a disc-shaped, phosphatic sclerite, the mostdistinctive character of the group is a prominent set of internal scars, interpreted as representing sites of former muscleattachment. Predominantly based on muscle scar distribution, mobergellans have been compared to brachiopods,bivalves and monoplacophorans; however, a recurring theory that the sclerites acted as an operculum remains untested.Rather than correlate the number of muscle scars between taxa, here we focus on the percentage of the inner surfaceshell area that the scars constitute. We investigate two mobergellan species, Mobergella holsti and Discinella micans,and compare the Cambrian taxa with the muscle scars of a variety of extant and fossil marine invertebrate taxa to testwhether the mobergellan muscle attachment area is compatible with an interpretation as operculum. The only skeletalelements in our study with a comparable muscle attachment percentage are gastropod opercula. Complemented withadditional morphological information, our analysis supports the theory that mobergellan sclerites acted as an operculumpresumably from a tube-living organism. The paucity of tubes co-occurring with mobergellan sclerites could beexplained by the transportation and sorting of detached opercula, while the corresponding tube remained attached tosubstrata in shallower water. The operculum perhaps performed a similar role to that seen in serpulid annelids and inneritid gastropods sealing the living chamber of the organism to avoid desiccation or for protection.
The holotype of the lower-middle Pliocene hyaenid Lycyaenops rhomboideae is redescribed and compared with contemporaneous hyaenids of the genera Lycyaena, Hyaenictis, Chasmaporthetes and Pliocrocuta. These comparisons show that the material represents a valid and distinct genus and species. The genus Lycyaenops is referred to the Chasmaporthetes lineage on the basis of its two-cusped ml talonid with reduced entoconid, reduced posterolingual cingulum cusp on p4 and premolar accessory cusps set in a straight line. It is distinguished from all other genera of that lineage by its smaller premolar accessory cusps, broad premolars and squaredoff and very broad posterior premolar shelves. The species L. silberbergi, previously assigned to Chasmaporthetes, is also referred to Lycyaenops. It differs from L. rhomboideae in its greater development of the premolar accessory cusps and less developed posterior premolar shelves, but shares the broad, squared-offpremolars. The interrelationships of Hyaenictis, Chasmaporthetes and Lycyaenops are at present best described by an unresolved trichotomy, with Lycyaena as its sister taxon.
The topotypic material of the giant Late Miocene hyaenid Allohyaena kadici Kretzoi is described. New data on the deciduous dentition shows unambiguously that A. kadici is a hyaenid and not a percrocutid as reported by some previous authors. A. kadici is compared to the large hyaenids Adcrocuta eximia and Crocuta crocuta. These comparisons show that A. kadici has a mixture of primitive characters such as dp4 morphology, retention of m2, long and slender premolars and a large protocone on P4, and derived characters such as a preparastyle on P4, an internal root on P3 and a uniquely derived talonid structure of m 1. This combination of features makes A. kadici difficult to classify, but it is considered to probably be most closely related to derived, bone-cracking hyaenids such as Pachycrocuta and Crocuta. A. kadici is rare in the fossil record, being found at only two sites. We suggest that the reason for this rarity is that it had a geographic and stratigraphic range which is poorly sampled in the Miocene fossil record of Europe.
This paper consists of a taxonomic and systematic revision of the extinct felid genus Dinofelis (Felidae, Machairodontinae) and an analysis of its ecomorphology and evolution. Dinofelis has a broad distribution, with material from all northern continents and Africa, the latter of which was the apparent centre of evolution of the genus. We describe new material of Dinofelis from a number of sites in eastern Africa and reconsider all previously described material. We name two new species and identify several other distinct species-level taxa but refrain from naming these due to a paucity of well-preserved material. At the same time, we synonymize the two named Asian species, D. cristata and D. abeli, of which the former has priority. There are few characters useful in systematic analysis, but we can suggest at least one migration from eastern to southern Africa. Ecomorphological analysis of both craniodental and postcranial characters suggests that Dinofelis in many respects converged on modern pantherine cats in morphology and behaviour, a trend culminating in the South African D. barlowi and the Asian D. cristata, which are the most pantherine-like of all machairodont felids. This trend is reversed in the evolution of the youngest species, D. piveteaui, which is also the most machairodont in its ecomorphology. The timing of the extinction of Dinofelis is difficult to determine. Outside Africa material is scarce at all times, while in Africa the apparent extinction of Dinofelis at about 1.4 Mya coincides with the end of the good, semi-continuous fossil record present in eastern Africa from about 4Mya onwards. Dating of Kanam East (with D. piveteaui) to the Jaramillo Subchron (1.070–0.990 Mya) suggests possible survival considerably later. Thus, the extinction datum for Dinofelis cannot at present be firmly established.
This paper presents an up-to-date and detailed overview of the Plio-Pleistocene fossil record of Carnivora in eastern Africa. Major events in the carnivoran lineages present in the region are discussed and stratigraphic ranges of all species-level taxa are provided. The compiled data are used for quantitative analyses of species richness and turnover. Sampling is considered to be adequate for the interval 3.6–1.5 Mya, and poorer in the half-million-year time slices before and after this interval. Species richness peaks around 3.6–3.0 Mya and declines gradually from that time until the end of the time period analysed. Calculation of origination and extinction rates indicate that there are two peaks of origination: at 3.9–3.3 Mya (although the earlier half of this interval is biased through poor sampling) and at 2.1–1.8 Mya. The origination rate is zero in the interval 3.0–2.4 Mya. The extinction rate peaks at around 3.0 Mya after which it falls slightly, remaining nearly constant until 1.8 Mya, after which it increases considerably. The data support the hypothesis that the modern carnivoran guild of eastern Africa originated relatively recently, mostly within the last million years. There is no support in these data for a turnover pulse in Carnivora between 3 and 2 Mya.
The fossil hyaenids from Langebaanweg in South Africa are revised taxonomically using both morphological comparisons and measurement data. Ictitherium preforfex is found to be a synonym of Ikelohyaena abronia. Other hyaenid taxa in this fauna are Hyaenictitherium namaquensis, Chasmaporthetes australis and a new taxon similar to Chasmaporthetes australis in the size and shape of the M1 trigonid and other characters, but differing from this taxon in having short P3 relative to P2, a smaller anterior accessory cusp on P4 and M2 present. This taxon has previously been referred to Euryboas sp., but comparison with Eurasian hyaenids indicates that it shares diagnostic characters with Hyaenictis graeca, type species of the genus Hyaenictis. This genus is poorly known and its content is reviewed. We find that only the new species from Langebaanweg, formally described as Hyaenictis hendeyi sp. nov., and the Spanish Hyaenictis almerai probably belong in this genus, while other taxa intermittently referred to Hyaenictis belong to other genera. Thus, neither Leecyaena bosei nor Chasmaporthetes silberbergi belong in Hyaenictis.
Hagfishes from New Zealand are reviewed and a phylogeny proposed using morphological and genetic data (DNA sequences of cytochrome c oxidase subunit I gene, COI, and the small subunit RNA, 16S). Eptatretus cryptus sp. nov. was previously confused with Eptatretus cirrhatus (Forster in Bloch & Schneider, 1801) because of their similar morphology, and is found from the Three Kings Islands to Stewart Island and in the eastern part of the Chatham Rise (at depths of 96–922 m). Eptatretus poicilus sp. nov. is endemic to the Three Kings Islands, where it is common and associated with soft sediment and deep-sea coral-sponge habitats (114–842 m). Neomyxine caesiovitta sp. nov. is a slender hagfish found along the east coast of the North Island south to the Chatham Rise (430–1083 m). A neotype is erected for E. cirrhatus (type locality: Breaksea Sound, Fiordland), occurring widely in New Zealand coastal, shelf, and slope waters (1–922 m), but not at the Three Kings Islands. Eptatetrus goliath Mincarone & Stewart, 2006, Neomyxine biniplicata (Richardson & Jowett, 1951), and Nemamyxine elongata Richardson, 1958 are further described using additional material. Rubicundus eos (Fernholm, 1991) is still only known from the holotype (type locality: Challenger Plateau). Genetic results showed that the New Zealand Eptatretus species form a monophyletic group within the subfamily Eptatretinae, indicating likely speciation from a single common ancestor within the area. Eptatretus poicilus sp. nov. is the sister species of E. cirrhatus, and E. cryptus sp. nov. is closely associated with the clade formed by these two species. Eptatretus goliath is most closely associated with Eptatretus minor Fernholm & Hubbs, 1981 (Gulf of Mexico), these two species basally diverging within New Zealand hagfishes. The endemic genus Neomyxine forms a well-supported monophyletic group of as yet uncertain position within the phylogenetic tree. A key to the New Zealand hagfishes, fresh colour photographs, distribution maps, and in situ video recordings are presented