Paralygodium meckertii sp. nov. (Schizaeaceae) from the Upper Cretaceous (Coniacian) of Vancouver Island, British Columbia, Canada

More than 50 specimens of permineralized fertile pinnules with abaxially borne sporangia have been discovered in calcareous marine nodules from the Upper Cretaceous (Coniacian) Comox Formation from the Eden Main localities on Vancouver Island, British Columbia, Canada. Isolated pinnules 1.6–3.0 mm wide × 1.6–2.8 mm long are lobed and abaxially enrolled to form irregular globose structures. Pyriform sporangia 216–300 μm wide × 360–468 μm long occur in two rows on the abaxial surface of pinnule lobes. Sporangia have an apical annulus of 15–18 cells. Spores are tetrahedral and trilete, 33–42 μm in diameter, with straight to concave interradial sides, laesurae extending nearly to the equator, and a psilate exine. Spores are assignable to the sporae dispersae genus Deltoidospora. Fertile pinnules are compared to fossils of Anemia poolensis and two previously described species of Paralygodium, and show closest similarities to P. vancouverensis from the Eocene of British Columbia. The Cretaceous Eden Main specimens differ in number of pinnule lobes and their morphology and are described as a new taxon: P. meckertii sp. nov. This discovery extends the Cretaceous geographic range of Paralygodium from Japan to North America and adds to our knowledge of the diversity of extinct schizaeaceous ferns.     

Comparative pollen morphology and ultrastructure of Mentheae subtribe Nepetinae (Lamiaceae)

This study provides new pollen data of 52 representative species belonging to all 12 genera in the currently classification of the subtribe Nepetinae, and considers the possible presence of orbicules for the first time. Pollen morphology and ultrastructure were investigated with light, scanning electron and transmission electron microscopy. Nepetinae pollen is small to large (P = 16–65 µm, E = 17–53 µm), oblate to prolate (P/E = 0.7–1.6) in shape and mostly hexacolpate (sometimes octocolpate). The exine stratification in all taxa studied is similar and characterized by unbranched columellae and a continuous, granular endexine. Sexine ornamentation in the Nepetinae is bireticulate, microreticulate or perforate. In perforate and microreticulate pattern a tendency towards a bireticulum could be recognized due to trace of secondary tectal connections. The bireticulate pattern is most common with variations of primary muri and secondary reticulum. In Hymenocrater and Schizonepeta the observed variation of sexine ornamentation is particularly valuable at the generic level. Pollen data support Lophanthus and Nepeta as very closely allied and Lallemantia is clearly distinct from Dracocephalum. The formerly suggested infrageneric relationships within Dracocephalum and Nepeta are only partly corroborated by palynological characters. Orbicules are absent in the Nepetinae.     

陕西横山晚三叠世鱼类游泳遗迹化石新材料

在多次赴化石产地陕西横山县进行大规模化石发掘后,获得一批完整精美的遗迹标本,为其中鱼类游泳遗迹化石标本建立了新种Undichna prava,并重新修订U.britannica,U.tricosta两种的特征,通过遗迹形态恢复鱼体长度为50—96cm,普遍大于以往描述的国内外据遗迹标本恢复的鱼体长度。     

山东济阳坳陷古近系沙河街组深水湖沉积中的遗迹化石

山东济阳坳陷古近系沙河街组深水湖沉积地层主要由深灰色、褐灰色泥岩、油泥岩、泥灰岩和石灰岩以及岩盐组成,浊流沉积发育。已发现深水型遗迹化石有12个遗迹属14个遗迹种,包括3个新遗迹属6个新遗迹种。根据这些遗迹化石的组成与分布特征及其围岩的沉积特征,可以划分出2种不同沉积环境下的遗迹化石群落,即(1)Mermoides-Neonereites遗迹群落,主要由觅食迹(Fodinichnia)和牧食迹(Pascichnia)组成,常见分子有Mermoides chezhenensis,Mermoides latiusculus,Neonereites uniserialis,Hel minthoidichnitescf.tenuis,Hel-minthopsis abeli,Pilichnus lacustris,Multilagueichnus lingpanensis,Cochlichnus anguineus,Gordiaichnosp.,Palaeophycus tubularis和Planolites beverleyensis等,它们被解释形成于半深水湖或较深水湖沉积环境;(2)Semi-rotundichnus遗迹群落,以半圆形、小碟形牧食迹为其特征,典型组成分子有Semirotundichnus dongyingensis,Pa-tellarisichnus boxingensis和Neonereites uniserialis等,它们均产生于深水湖沉积环境。     

Dung-Beetle Fossil Brood Balls: The Ichnogenera Coprinisphaera Sauer and Quirogaichnus (Coprinisphaeridae)

Coprinisphaera is one of the most common trace fossils in South American paleosols from the Eocene to the Recent. Nevertheless, an ichnotaxonomical review of this ichnogenus has been lacking until now. The revision of hundreds of specimens of Coprinisphaera from numerous formations in Argentina, Uruguay and Ecuador has resulted in the recognition of two ichnogenera. One of them, Coprinisphaera, includes isolated, spherical, subspherical, pear-shaped and bispherical structures grouped in five ichnospecies: C. ecuadoriensis Sauer, C. murguiai (Roselli), C. kraglievichi (Roselli), C. tonni isp. n., and C. kheprii isp. n. The new ichnogenus and ichnospecies, Quirogaichnus coniunctus, consists of Coprinisphaera-like structures clustered in a common excavated chamber. The ichnotaxobases for the taxonomical arrangement of Coprinisphaera are mostly related to the presence and position of a small chamber (interpreted as the original egg chamber) with respect to a large chamber (provision chamber) and emergence hole. The egg chamber may be included in (1) the provision chamber, leaving no remains in the trace fossils and resulting in cylindrical emergence holes; (2) the wall of the provision chamber, without additional structures; and (3) a mamillate to spherical additional structure, external to the provision chamber, resulting in pear-shaped to bispherical trace fossils.     

Ichnologic Note A New Ichnospecies of Cardioichnus from the Cretaceous (Albian) of New Mexico

A new ichnospecies of Cardioichnus, Cardioichnus biloba isp. nov., is described and documented from shallow marine strata of Cretaceous (Late Albian) age in southern New Mexico, USA. It is a heart-shaped resting trace which, unlike all other ichnospecies of Cardioichnus, is epichnial and increases in width to a bilobate trace, often with a raised anterior terminus. Only the posterior end of this trace is associated with Bichordites burrows, and the anterior end is bilobate and undisturbed. This represents a resting position which differs from other known species of this cubichnium, which are hypichnial and subquadrate in symmetry. The tracemaker is a spatangoid echinoid, most likely Heteraster d'Orbigny, 1853.     

川西峨眉晚白垩世夹关期河流沉积中的痕迹化石群落*

晚白垩世夹关组中的痕迹化石群落至少由12个痕迹属17个痕迹种组成,其中包括5个新痕迹种,即Cystichrtium cuwatitivum,Steinichnus laryus,Paradidymaulichnus emeiertsis,Monmorphichnus lineates和Rusophycus univalvis.这一化石群落主要是无脊椎动物的进食迹、觅食迹、爬迹、停息迹和居住迹,其中多数呈下浮痕和全浮痕保存,并形成于经常干旱的河流环境(大多出现在泛滥平原沉积中).该群落可识别出两个痕迹化石组合,即1) Scoyenia-Steinichnus-Rusophycus组合,它主要产自泛滥平原和漫滩环境;2)Skolithos-Arenicolites组合,它代表一种水道砂坝或曲流砂坝环境.     

A LEAFCUTTER BEE TRACE FOSSIL FROM THE MIDDLE EOCENE OF PATAGONIA, ARGENTINA, AND A REVIEW OF MEGACHILID (HYMENOPTERA) ICHNOLOGY

Abstract:  The ichnospecies Phagophytichnus pseudocircus isp. nov. is described to include trace fossils characterized by leaf-margin excisions showing eccentricity values of 0.35–0.65 and more than 270 degrees of an arc, a non cuspate margin and vein stringers or necrotic flaps of tissue along the margin. A method for determining ellipse eccentricity was performed on leaf discs obtained from the nests of the modern leafcutter bee Megachile rotundata (Hymenoptera: Megachilidae), which provided objectively obtained values comparable to the trace fossil from the middle Eocene of Argentina and other world-wide ichnological records, historically and subjectively considered to be 'circular' trace fossils and attributed to leafcutter bees. The material described herein represents the first evidence for fossil Megachilidae from the Southern Hemisphere.     

Holocene glaciations in the Ema Glacier valley, Monte Sarmiento Massif, Tierra del Fuego

Investigations carried out in the Ema Glacier valley, Tierra del Fuego, on the eastern side of Monte Sarmiento Massif, enable the recognition of five Holocene glacial events. The oldest glacial advance deposited the so-called external moraines of Ema Glacier, with a probable occurrence between 6000 and 5000 14 C y BP without discarding the potential for these deposits to be from Lateglacial time. The remaining four readvances built up a complex inner moraine system named informally internal moraines of Ema Glacier. The oldest recognized till unit that constitutes this proximal moraine system was deposited shortly before 3135 14 C y BP, when glaciolacustrine sedimentation took place during glacier recession. Subsequent glacial advances accumulated till at about 1288 14 C y, shortly after 695 14 C y, and between 379 14 C y and 60 y BP. This chronology of Holocene glacier events coincides with and is well complemented by the one established by other authors for Fiordo Pía at Cordillera Darwin, 75 km to the east. The Ema-Pía chronology is used to calibrate tentatively a series of moraine belts previously identified in the mountain ranges adjacent to Ushuaia, 150 km SE of the surveyed region. A comparative chart shows that the chronological data obtained for the neoglacial readvances in Tierra del Fuego are in accordance with those for the southern Patagonian Andes further north. It follows that the Holocene behavior of the glaciers in the Andean region of Tierra del Fuego and southern Patagonia is essentially a response to the same regional climate change.     

南极利文期顿岛晚三叠世复理石相遗迹化石

南极利文斯顿岛赫德半岛中的迈尔斯陡崖组主要是浅变质的石英长石杂砂岩、粉砂岩、泥岩和粉砂岩与泥岩互层等组成的复理石,厚度可能超过３０００m,形成于浊积扇的上扇和下扇部分,时代可能为晚三叠世。在复理石相岩石中发育一套深水的遗迹化石,共有１５个遗迹属、１６人遗变种,其中有１０个可以鉴定到遗迹种,两个比较种,４个只鉴定到遗迹属,未鉴定到遗迹种,１建立１个新遗迹属及新遗迹种,除新遗迹属种外,其余１４个遗迹属,１５个遗迹种都曾经在深海复理石相浊积岩内发现过,其中Ｂelorhaphe,Glockerichnus,Lophoctenium,Rhabdo-glyphus,Paleodictyon,Suborenzinia,Spirophycus,Strobilorhaphe,Tuberculicnus,Cochlichnus等,属于浊流前产生在复理石相泥岩内的高度分异的雕画迹（Ｇraphoglyptida),它们产于泥岩却保存为上覆砂岩底面的铸型凸起。别外,Ｆucusopsis和Neonereites却产生在砂岩内代表浊流后形成的沉积后遗迹组合,文内还描述３种浊流常见的无机构造,并上上述遗迹化石进行比较。     

Addition of dissolved nitrogen and dissolved organic carbon from wild fish faeces and food around Mediterranean fish farms: Implications for waste-dispersal models

Leaching of ammonium (NH₄⁺) and dissolved organic carbon (DOC) from food pellets used at three fish farms in the Mediterranean Sea and the faeces of four different species of farm-associated wild fish (Trachurus mediterraneus, Mugil cephalus, Trachinotus ovatus and Boops boops) were determined. They were placed in seawater and agitated slowly (5 cm s^− 1) to reflect natural conditions during their fall to the sediment. Two temperatures were tested, 25 °C and 15 °C, to assess the influence of seasons on leaching rates. Leaching from fish faeces was generally higher compared to food pellets. T. mediterraneus faeces leached more NH₄⁺ and DOC than M. cephalus, T. ovatus and B. boops. The results showed that there is an important addition of NH₄⁺ and DOC to the water column during sinking of the faeces and that this is species-dependent. Water turbulence and faeces composition seemed to have a higher influence than temperature on the leaching process. Due to the high abundance and biomass of farm-associated fish in the Mediterranean and their capacity to remove waste, they appear to be an important component for models that predict the impact of aquaculture. Large biomasses of wild fish at fish farms may reduce the impact on benthic systems but increase the nitrogen and carbon loads into the water column, affecting the pelagic system and modifying the spatial dispersion of wastes.     

Insights on the Behavior of Late Paleozoic Aquatic Crustaceans (Pygocephalomorpha?): Compound Trace Fossils from Western Argentina

We describe intergradations between the arthropod repichnial trace fossils Diplichnites gouldi (Gevers et al., 1971), Dendroidichnites Demathieu et al., 1992, and Monomorphichnus Crimes, 1970 with two distinct cubichnial traces, Gluckstadtella cooperi Savage, 1971 and Huilmuichnus santracruzensis new ichnogenus and ichnospecies. These compound ichnofossils are part of high ichnodiversity arthropod-dominated trace fossil associations from the Late Carboniferous Agua Escondida Formation of the San Rafael Basin (Argentina). The complex ichnotaxonomy of Diplichnites and the ichnospecies D. gouldi are discussed and some possible working solutions are proposed. The most likely producer of the compound trace fossils are the Pygocephalomorpha, a group of Late Paleozoic crustaceans that are recorded in nearby basins from Uruguay and Brazil. The compound trace fossils are used to infer a number of complex behaviors of pygocephalomorphs in a subaqueous setting, including caridoid (tail flip) or more primitive escape reactions, landing followed by resting and transient resting during normal walking. In addition, different gaits can be inferred from well-preserved D. gouldi, which can be correlated with contrasting trackway morphology.     

Parataenidium,a new taenidium‐like ichnogenus from the carboniferous of Ireland

The new ichnogenus Parataenidium is erected for backfilled tubular trace fossils that can appear superficially similar to Taenidium, but are divided horizontally into two distinct levels. Two ichnospecies are recognised: Parataenidium mullaghmorensis isp. nov. and Parataenidium moniliformis (Tate 1859). The latter ichnospecies is transferred from Eione Tate 1859, which is a junior homonym of Eione Rafinesque 1814, and therefore unavailable for Tate's ichnotaxon. The ichnogenus is an important component of late Paleozoic shallow‐water siliciclastic sediments, and can be considered as a “guide”; indicator for the Carboniferous.     

Ichnology and sedimentology of the early Permian deep-water deposits from the Lercara-Roccapalumba area (Western Sicily,Italy)

Summary Diverse and abundant trace fossils of the deep-waterNereites ichnofacies have been found in well-dated Early Permian deep-water turbidites (Lercara Formation) of western Sicily (Italy). Conodonts indicate a latest Artinskian to Cathedralian (late Early Permian) age. Microfossils (pelagic conodonts, albaillellid Radiolaria, paleopsychrospheric ostracods, foraminiferal associations dominated byBathysiphon), trace fossils (deep-bathyal to abyssalNereites ichnofacies) and sedimentologic data collectively indicate a deep-water environment for the Early Permian turbidites of the Lercara Formation. The dominance ofAgrichnium and of thePaleodictyon subichnogeneraSquamodictyon andMegadictyon suggests that this icnofauna is closely related in ichnotaxonomic composition to other late Paleozoic deep-water ichnofaunas. The occurrence ofAcanthorhaphe. Dendrotichnium andHelicoraphe, to date only reported from Cretaceous or Tertiary flysch deposits, suggests that the entire ichnofauna corresponds well to previously documented Silurian-Tertiary flysch ichnofaunas. Eight new ichnospecies and a new ichnosubgenus,Megadictyon, are described.     

New evidence for laurasian corystosperms: Umkomasia from the Upper Triassic of Northern China

Recent finds of remarkable fossil plants from the Upper Triassic Yangcaogou Formation in Liaoning Province, PR China include branched, cupule-bearing structures referable to the corystosperm ovulate organ Umkomasia. This material is described and assigned to the proposed new species Umkomasia asiatica. The collection includes numerous isolated cupules and fragments of ultimate cupule-bearing axes. Two specimens consisting of portions of the main axis with attached, cupulate lateral axes have also been found. The main axis was at least 6.5 cm long, with each lateral axis bearing one to at least three pairs of stalked, ovoid cupules. The new Umkomasia is similar to U. franconica from the Jurassic of Germany, which is the only other known laurasian species, but the cupules are smaller and more elongated. It is also similar to many gondwanan forms, including the type species U. macleanii. Leaves associated with the Chinese Umkomasia species are tentatively referred to Thinnfeldia, and may have been produced by the same plant. Associated ovoid seeds with elongated, curved micropyles are similar to those of gondwanan species of Umkomasia. The fossils described here are, therefore, significant in representing the first report of corystosperm reproductive structures from Asia, and only the second report of Umkomasia from the entire northern hemisphere. The new Chinese fossils also support leaf-based evidence that the Corystospermales were present in Laurasia as early as the Late Triassic.     

Middle Jurassic trace fossils from the Ridang Formation in Sajia County,South Tibet,and their palaeoenvironmental significance

An ichnofauna consisting of 18 ichnospecies (one of them new) in 14 ichnogenera are described for the first time from the Middle Jurassic Ridang Formation in Sajia County, South Tibet. The ichnofauna can be subdivided into two ichnoassemblages in ascending stratigraphic order: the Palaeophycus–Megagrapton ichnoassemblage in the lower and middle parts of the Ridang Formation, followed by the Cosmorhaphe–Nereites–Paleodictyon ichnoassemblage in the upper Ridang Formation. Overall, the trace fossils occur in a middle–distal turbidite fan sequence, as evidenced by both sedimentological analysis and the composition of the trace fossils. Several subenvironments of the middle–distal fan system have been recognized on the basis of the spatial distribution of the trace fossils. Typically, the channel-fill deposits in the middle part of the turbidite fan lack trace fossils, the interchannel and upper channel-fill (levee) subenvironments of the middle turbidite fan contain abundant facies-crossing trace fossils, in contrast to the distal part of the turbidite fan where deep-water trace fossils are dominant. The ichnofauna is similar to typical flysch ichnofaunas from Europe and North America in characteristics, and is interpreted to represent a typical deep-sea Nereites ichnofacies. The presence of these deep-sea trace fossils therefore would suggest that a continental slope environment existed in southern Tibet during the Middle Jurassic and the study area was located in a slope-abyssal plain setting.     

Seasonal changes in morphometric and biochemical endpoints in northern pike (Esox lucius), burbot (Lota lota) and slimy sculpin (Cottus cognatus)

1. Morphometric and biochemical endpoints were used to assess growth and energetics in young‐of‐the‐year (YOY) northern pike (Esox lucius), YOY burbot (Lota lota) and slimy sculpin (Cottus cognatus) collected upstream and downstream of a uranium mining operation in northern Saskatchewan, Canada. 2. Water sampled at sites downstream of uranium mining and milling effluent discharge was higher in certain trace metals (arsenic, molybdenum), ions (conductivity, hardness, ammonia and sulphate) and total dissolved solids compared with ecologically similar reference sites. 3. Overwinter survival potential was estimated by determining total body lipids and total body triglycerides in fishes collected in late autumn and early spring. Two‐factor anova indicated no site or season differences in total body lipids or triglycerides in YOY northern pike. In spring, burbot collected from the exposure site were higher in total body lipids and triglycerides compared with the previous autumn and compared with fish collected from the reference site. Slimy sculpin from both exposure and reference sites had lower total body lipid and triglyceride content in spring compared with the previous autumn. In addition, sculpin from the exposure site had lower total body lipids and triglycerides in spring compared with fish collected from the reference site. 4. Biochemical estimates of fish growth (muscle RNA/DNA ratio and muscle protein concentration) exhibited clear seasonal differences, with consistent decreases in this endpoint for all fish species in spring relative to the previous autumn at both exposure and reference sites. 5. Results for total body lipids and triglycerides were inconclusive and inconsistent between species and exposure scenarios. However, all species exhibited a similar seasonal decrease in muscle protein and to a lesser extent, muscle RNA/DNA ratio.     

Entrainment to light of circadian activity rhythms in tench (Tinca tinca)

The present article analyzes locomotor activity rhythms in Tinca tinca. To that end, three different experiments were conducted on 24 animals (20 g body weight) kept in pairs in 60-liter aquaria fitted with infrared sensors connected to a computer to continuously record fish movements. The first experiment was designed to study the endogenous circadian clock under free-running conditions [ultradian 40:40 min LD pulses and constant dark (DD)] and after shifting the LD cycle. Our results demonstrate that tench has a strictly nocturnal activity pattern, an endogenous rhythm being evident in 45.8% of the fish analyzed. The second experiment was conducted to test the influence of different photoperiods (LD 6:18, 12:12, 18:6, and 22:2) on locomotor activity, the results showing that even under an extremely long photoperiod, tench activity is restricted to dark hours. The third experiment examined the effect of light intensity on locomotor activity rhythms. When fish were exposed to decreasing light intensities (from 300:0 lux to 30:0, 3:0, and 0.3:0 lux) while maintaining a constant photoperiod (LD 12:12), the highest percentage of locomotor activity was in all cases associated with the hours of complete darkness (0 lux). In short, our results clearly show that (a) tench is a species with a strictly nocturnal behavior, and (b) daily activity rhythms gradually entrain after shifting the LD cycle and persist under free-running conditions, pointing to their circadian nature. However, light strongly influences activity rhythms, since (c) the length of the active phase is directly controlled by the photophase, and (d) strictly nocturnal behavior persists even under very dim light conditions (0.3 lux). The above findings deepen our knowledge of tench behavior, which may help to optimize the aquacultural management of this species, for example, by adjusting feeding strategies to their nocturnal behavior.     

Swimming trace of a coelacanth fish from the Lower Keuper of south-west Germany

Parundichna schoelli igen. nov., isp. nov. from the Middle Triassic (Ladinian) Lower Keuper of Rot am See (Baden-Württemberg, Germany) consists of clusters of sigmoidal scratches symmetrically arranged in a plaited pattern. It is here interpreted as the swimming trace of a large coelacanth fish. In contrast to ichnospecies of Undichna there is no unpaired groove left by the tail fin. Instead, the sets of parallel scratches resulted from the pendulum motion of two pairs of appendages, the pectoral and pelvic fins, which acted in alternation, as in tetrapods. This strange mode of swimming is compared to films of modern Latimeria and to computer simulations; it probably corresponds to a particular foraging behaviour. The presence of fittingly-sized coelacanths is documented in coeval carbonates (Alberti-Bank) by disarticulated skeletal elements. Since the Lower Keuper represents a fluvial and estuarine facies of the receding Muschelkalk sea, we cannot be sure whether this trace was made in a marine or freshwater environment.