Upper Cretaceous aquatic plants from Northern Mexico

Two aquatic plant genera assignable to Decodon (Lythraceae) and Ceratophyllum (Ceratophyllaceae) are described based on reproductive structures collected from the Cerro del Pueblo Formation (late Campanian [73.5 ma]), Coahuila, Northeast Mexico. Decodon is represented by three small seeds with a pyramidal shape, rounded borders, and a concave ventral surface with a rectangular valve towards the center of the seed ventral surface. The Ceratophyllum spiny fruit has an ellipsoidal central body and two proximal long spines flanking a short pedicel opposite the stylar projection. These new reports confirm the presence of both genera in the Upper Cretaceous sediments of Northeastern Mexico, and add to our recognition of diversity within the widely distributed freshwater communities along the margin of the epicontinental sea.     

Archamamelis,hamamelidalean flowers from the Upper Cretaceous of Sweden

Lignite fossil flowers (including pollen) and isolated stamens of probable hamamelidalean (possible hamamelidaceous) affinities from the upper Cretaceous (Late Santonian or Early Campanian) of Sweden are described. The flowers are 6–7-merous with probably a double perianth, one whorl of stamens and (2-?)3 carpels. The stamens are disporangiate; each theca opens by a valve towards the centre of the flower. Pollen is tricolpate, tectate-columellate and reticulate; the endexine is lamellated in the apertural region. The gynoecium has free styles and a syncarpous ovary. In the one flower that was serially sectioned the ovary is either non-functional or development of the few (2?) ovules is retarded.     

Cretaceous diversification of angiosperms in the western part of the Iberian Peninsula

The classic leaf fossil floras from the Cretaceous of the Lusitanian Basin, Portugal, which were first described more than one hundred years ago, have played an important role in the development of ideas on the early evolution of angiosperms. Insights into the nature of vegetational change in the Lusitanian Basin through the Cretaceous have also come from studies of fossil pollen and spores, but the discovery of a series of mesofossil floras containing well-preserved angiosperm reproductive structures has provided a new basis for understanding the systematic relationships and biology of angiosperms at several stratigraphic levels through the Cretaceous. In the earliest mesofossil floras from the Torres Vedras locality, which are of probable Late Barremian-Early Aptian age, angiosperms are surprisingly diverse with about 50 different taxa. In slightly later mesofossil floras, which are of probable Late Aptian-Early Albian age, the diversity of angiosperms is still more substantial with more than hundred different kinds of angiosperm reproductive structures recognized from the Famalicão locality alone. However, this early diversity is largely among angiosperm lineages that produced monoaperturate pollen (e.g., Chloranthaceae, Nymphaeales) and early diverging monocots (Alismatales). Eudicots are rare in these Early Cretaceous mesofossil floras, but already by the Late Cenomanian the vegetation of the western Iberian Peninsula is dominated by angiosperms belonging to various groups of core eudicots. The Normapolles complex is a particularly conspicuous element in both mesofossil floras and in palynological assemblages. In the Late Cretaceous mesofossil floras from Esgueira and Mira, which are of Campanian-Maastrichtian age, core eudicots are also floristically dominant and flowers show great organisational similarity to fossil flowers from other Late Cretaceous floras described from other localities in Asia, Europe and North America.     

Angiosperm leaves associated with Sinocarpus infructescences from the Yixian Formation (mid-Early Cretaceous) of NE China

Typical angiosperm dicot leaves are discovered closely associated with reproductive organs of Sinocarpus decussatus from the Yixian Formation, NE China. Leaves are of first rank, small, with fine texture, and with distinct petiole and lamina. Venation pattern is craspedodromous, of at least three discrete orders of veins irregularly arranged. Leaf margin is serrate, with glandular teeth of chloranthoid type. The new Sinocarpus material is better preserved and more complete than the type specimen. It yields support for previous interpretations of reproductive characters and shows that the inflorescences were compound, perhaps combining alternate and opposite phyllotaxis, and that seeds were arranged in two rows, each row with about ten seeds. While these new reproductive characters do not provide further resolution to the systematic assignment of Sinocarpus, the associated leaves, believed to be from the same plant, support previous interpretation of Sinocarpus as a basal eudicot, and particularly close to Ranunculales.     

Teixeiria lusitanica, a new fossil flower from the Early Cretaceous of Portugal with affinities to Ranunculales

A charcoalified fossil flower bud of a new genus and species (Teixeiria lusitanica) is described from the Early Cretaceous of Portugal. The flower is actinomorphic and unisexually male. At the base of the bud there are several bracts of different sizes, which are followed by sepal-like and petal-like tepals. Bracts and perianth organs seem to be arranged spirally and to exhibit transitions between different organ categories. The androecium has numerous stamens in two sizes, but with unclear arrangement. Pollen is small and tricolpate with a perforate tectum and a densely columellate infratectal layer. No carpels or remains of carpels could be observed on the floral axis. Teixeiria lusitanica shows most affinities to members of Ranunculales. There are also some similarities with Berberidopsis (Berberidopsidaceae, Berberidopsidales) and members of the Saxifragales (Hamamelidaceae and Daphniphyllaceae).     

Reconstruction of a Lower Cretaceous conifer

Remains of Pseudofrenelopsis parceramosa (Fontaine) Watson (Cheirolepidiaceae) from the Wealden of the Isle of Wight have been examined from the point of view of the branching and mode of growth of the plant. Evidence is presented that the tree exhibited seasonal growth and that the young extension shoots bore numerous temporary ultimate branch? is of limited growth. The tree was probably adapted to warm seasonally arid conditions.     

Sorophores of<Emphasis Type="Italic">Lygodium</Emphasis> Sw. (Schizaeaceae) from the Late Cretaceous of New Jersey

We report here on a series of specimens of charcoalified sorophores with characteristics of the extant fern genusLygodium (Schizaeaceae) collected from sediments of the Raritan Formation (Late Cretaceous). Each elongate lobed fertile pinnule (sorophore) is flattened and bears alternately arranged sporangia on one surface. Each sporangium is covered by an indusium continuous with the margin of the lamina. Sporangia are oblong in shape, short stalked, and have an apical annulus formed by a single ring of radiating cells that dehisces longitudinally. The sporangial cap or distal face is formed by only one cell. All of these features are characteristic of the extant genusLygodium. Small numbers of trilete, psilate spores are found in the sporangia. Megafossils assignable toLygodium are known from the Upper Cretaceous of North America and Germany with worldwide distribution during the Tertiary. The newLygodium fossils are compared with others previously referred to the genus.     

Occurrence of Sapindopsis (Platanaceae) in the Cretaceous of Eurasia

Three new species of the genus Sapindopsis Fontaine from Central Asia and western Siberia are described: S. neuburgae (Vachr.) Golovn., comb. nov., S. janschinii (Vachr.) Golovn., comb. nov., and S. kryshtofovichii (I. Lebed.) Golovn., comb. nov. Geographical and stratigraphic analyses have shown that the genus evolved in Eurasia from the Middle Albian to the Cenomanian, and was mostly restricted to the subtropics of the Euro-Sinian phytogeographic area from the Middle East to Russian Primorye and northern China. The are no reliable records of Sapindopsis from Europe. The migration of Sapindopsis from North America to Eurasia through the Bering Land Bridge was most probably related to the Early-Middle Albian climatic optimum.     

Fossil flowers and pollen ofLauraceae from the Upper Cretaceous of New Jersey

A fossil trimerous flower from the Turonian (ca. 90 MYBP, Upper Cretaceous) of New Jersey is described as a new genus in the familyLauraceae. The fossil flower is charcoalified and preserved in exceptional detail. This fossil specimen is particularly remarkable in that several pollen grains have been preserved; pollen grains ofLauraceae generally have very thin exine and are rarely preserved in the fossil record. Although the specimen is incomplete and lacks anthers, there are sufficient structural details preserved to permit an assignment to theLauraceae, as well as comparisons with the tribePerseeae. This new genus provides an important addition to our knowledge of systematic and structural diversity in CretaceousLauraceae.     

Structure and affinities of the petrified plants from the cretaceous of northern Japan and Saghalien XI A cupressoid seed cone from the Upper Cretaceous of Hokkaido

Archicupressus is a new genus of the Cupressaceae based on a permineralized conifer female cone from the Upper Cretaceous of Hokkaido. The type species,Archicupressus nihongii sp. nov., is characterized by peltate bract-scale complexes consisting of a completely fused bract and scale bearing erect seeds. Bract-scale complexes are arranged in whorls of three on the cone axis. Each complex has a bristle-like projection, the bract apex, at the top. Affinities to some genera in the Cupressaceae are discussed. Consecutive number from the previous paper (Ohsawaet al., 1992). Supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Science and Culture of Japan to Makoto Nishida, No. 02640533.     

Structure and affinities of the petrified plants from the cretaceous of Northern Japan and Saghalien. XII.Obirastrobus gen. nov., petrified pinaceous cones from the Upper Cretaceous of Hokkaido

Two new species of pinaceous cones belonging toObirastrobus gen. nov. are described from the Upper Cretaceous of Hokkaido. Bract-scale complexes are arranged helically and each consists of a small bract and a large scale. The bract and scale are separated. The scale tapers distally and its apex does not become papery. The anatomy of the bracts, scales, and seeds shows a combination of features unique in the Pinaceae and resembling those of the extant genusKeteleeria and the extinct genusPseudoaraucaria. Consecutive number from the previous paper (Ohsawaet al., 1992). Supported by Grant-in-Aid for Scientific Research from the Ministry of Education, Science and Culture Nos. 63540545 and 02640533 to Makoto Nishida.     

Chloranthaceous floral structures from the Late Cretaceous of Sweden

New chloranthaceous floral structures from the Late Cretaceous (Late Santonian/Early Campanian) of Scania, southern Sweden, have provided important new information on theChloranthistemon plants. The material includes well preserved fragments of inflorescence axes with flowers in situ documenting thatChloranthistemon flowers were bisexual and closely resembled those of extantChloranthus (Chloranthaceae). An emended diagnosis is given for the type species of the genus,Chloranthistemon endressii, and a new species,C. alatus, is described. The flowers ofChloranthistemon are small, perianthless and strongly zygomorphic, consisting of a tripartite and broadened androecium borne in an abaxial to lateral position on the monocarpellate ovary, and arranged in the axils of decussate bracts. Stamens are either completely free (C. alatus), or free at the base and coherent at the apex (C. endressii). The apical connective is extensive in both species; elaborated into conspicuous wing-like structures inC. alatus, or into a massive and shield-like structure inC. endressii. Pollen grains ofC. endressii are spheroidal, and reticulate and spiraperturate, while those ofC. alatus are ellipsoidal, tectate and foveolate with a unique combination of a distal colpus and a proximal furrow (colpus?) perpendicular to each other. Ovaries observed in well preserved flowers of both species are small and undifferentiated. Larger, dispersed fruits of chloranthaceous affinity are abundant and distinct, and probably represent at least two or three species, but cannot be linked with certainty to any of theChloranthistemon species described here.     

Canrightiopsis,a new Early Cretaceous fossil with Clavatipollenites-type pollen bridge the gap between extinct Canrightia and extant Chloranthaceae

Canrightiopsis with three species (C. intermedia, C. crassitesta, C. dinisii) is described from the Early Cretaceous of Portugal based on small, one-seeded berries. The fruits are derived from bisexual flowers with three stamens borne on one side of the ovary. There are no traces of a perianth. Pollen is of the Clavatipollenites-type, monocolpate, semitectate, reticulate-columellate with heterobrochate reticulum and muri with beaded supratectal ornamentation. The ovary is unilocular with a single pendant, orthotropous and bitegmic ovule. The seed is endotestal. The endotesta consists of one layer of palisade-shaped crystal cells with fibrous infillings. The fruit wall has resin bodies or cavities from presumed ethereal oil cells sometimes seen as stomata-like structures on the fruit surface. A phylogenetic analysis resolves Canrightiopsis as a close relative of extant Chloranthaceae, particularly close to extant Chloranthus and Sarcandra. All three taxa share the one-sided position of the stamens on the ovary. An evolutionary sequence from fossil Canrightia to fossil Canrightiopsis and extant Chloranthus and Sarcandra is suggested by loss of perianth, reduction in number of ovules and stamens and displacement of stamens to one side of the ovary. Canrightiopsis also shares several critical features with extant Ascarina including monoaperturate pollen and beaded supratectal ornamentation of the pollen wall.     

Cretophengodidae,a new Cretaceous beetle family,sheds light on the evolution of bioluminescence

Bioluminescent beetles of the superfamily Elateroidea (fireflies, fire beetles, glow-worms) are the most speciose group of terrestrial light-producing animals. The evolution of bioluminescence in elateroids is associated with unusual morphological modifications, such as soft-bodiedness and neoteny, but the fragmentary nature of the fossil record discloses little about the origin of these adaptations. We report the discovery of a new bioluminescent elateroid beetle family from the mid-Cretaceous of northern Myanmar (ca 99 Ma), Cretophengodidae fam. nov. Cretophengodes azari gen. et sp. nov. belongs to the bioluminescent lampyroid clade, and would appear to represent a transitional fossil linking the soft-bodied Phengodidae + Rhagophthalmidae clade and hard-bodied elateroids. The fossil male possesses a light organ on the abdomen which presumably served a defensive function, documenting a Cretaceous radiation of bioluminescent beetles coinciding with the diversification of major insectivore groups such as frogs and stem-group birds. The discovery adds a key branch to the elateroid tree of life and sheds light on the evolution of soft-bodiedness and the historical biogeography of elateroid beetles.     

Two New Species of the Early Cretaceous Filicinae and Their Taxonomical Study

Mainly based on the characters of the fertile segments, two new species of the Early Cretaceous ferns:Athyrium hulunianurn Chen, Ren et Deng (sp. nov. )and A. hailaerianurn Deng et Chen (sp. nov. ) have been nominated from the Yimin Formation, Zhalainuoer, Nei Monggol.     

A two-headed reptile from the Cretaceous of China

A malformed embryonic or neonate choristoderan reptile from the Lower Cretaceous Yixian Formation of northeastern China is described. The tiny skeleton exhibits two heads and two necks, with bifurcation at the level of the pectoral girdle. In a fossil, this is the first occurrence of the malformation known as axial bifurcation, which is well known in living reptiles.