Echiura from the Pennsylvanian Essex Fauna of northern Illinois

The first unequivocal fossil echiuran, Coprinoscolex ellogimus gen. et sp.n., is described from the Middle Pennsylvanian Francis Creek Shale of the Mazon Creek area of northeastern Illinois. Specimens are whole-body impressions within siderite concretions. They show anterior proboscides, cigar-shaped trunks, convoluted alimentary canals, and cylindrical pellets. Lack of setae suggests classification in the Family Bonelliidae. Coprinoscolex was most likely a marine deposit-feeder, either crawling over the sediment surface or burrowing to shallow depths while ingesting sediment. While this occurrence does not confirm or deny an annelidan ancestry for the Echiura, it indicates that by the Pennsylvanian, echiurans were unsegmented and essentially modern in form.     

Burrowing,grooming, and feeding behaviour of Paraceradocus,an antarctic amphipod genus (Crustacea)

Summary Species of the amphipod genus Paraceradocus found near the Antarctic Peninsula were observed in aquaria. The animals live under stones in burrows in sediment which they excavate with their gnathopods. During burrowing the animal regularly turns backwards in a somersault-like movement. Paraceradocus feeds on detritus, which is manipulated by the gnathopods and the antennes. The gnathopods are also used for grooming. A dense brush of setae at the medial surface of the carpi of the gnathopods I is used to clean off fine particles from the antennes. These particles are transferred to the maxillipeds and are ingested. The rear appendages are mainly cleaned by the gnathopods II. Young animals sitting between the gnathopods of the adult participate in feeding.     

The position of the Haplotaxidae in the evolution of oligochaete annelids

The Haplotaxidae have all the characteristics to support the hypothesis that they are the living descendents of the stem forms from which all of the Oligochaeta Clitellata (Orders Lumbriculida, Haplotaxida, Lumbricida, Tubificida) can be derived. The Aphanoneura are distinct from the Clitellata and are raised to a separate Class. There is no evidence to support the view that the elaborate setae of many Tubificida are derived from a polychaete ancestry; both are held to be independent modifications to aquatic life derived from a simple burrowing protoannelid with lumbricine setae.     

斜脉蝠蛾幼虫分类特征研究

本文研究报道了冬虫夏草主要寄主之一斜脉蝠蛾Hipialus oblifurcus Chu et Wang幼虫头、胸、腹各部分的形态特征、颜色、毛序及各龄幼虫的头宽和体长,可作为鉴别种类的依据。     

吴氏角叶蚤幼虫形态记述及其与同属另外三种的比较（蚤目：角叶蚤科）

描述了吴氏角叶蚤Ceratophyllus wui Wang et Liu 的幼虫形态,并与同属三种蚤幼虫作比较,标本采自湖北省西北部神农架海拔2 300 m 短嘴金丝燕四川亚种 Collocalia brevirostris innominata巢窝内。     

革板螨属3新种和派伦螨属1新种（蜱螨亚纲：中气门目：派盾螨科）

记述革板螨属3新种和派伦螨属1新种：井冈山革板螨Gamasholaspis jinggangshanensis sp．nov．,何氏革板螨Gamasholaspis hochyicheni sp．nov．,新阿革板螨Gamasholaspis novakimotoi sp．nov．和沙县派伦螨Parholaspulus shaxianensis sp．nov．     

中国派盾螨科三新纪录属及三新种记述(蜱螨亚纲：革螨股)

记述派盾螨科3新种：武汉派盾螨Parholaspis wuhanensis sp.nov.,亚弧讷派螨Neparholaspis subarcuatus sp.nov.和湖北真派螨 Euparholaspulus hubeiensis sp.nov.。三属均为中国首次记录。     

Seasonal dynamics of Callibaetis willineri (Ephemeroptera, Baetidae) associated with Eichhornia azurea (Pontedericeae) in Guaraná Lake of the Upper Paraná River, Brazil

The micro-anatomy of the cephalon is described in the troglobic asellotan isopod Craseriella anops from the Nohoch Nah Chich anchialine cave system in southeast Mexico. The cephalon is entirely covered by cuticular scales bordered by marginal spines. The anterior end of the cephalon is bordered by a carina that is wider medially. The isopod is eyeless. The distal seventh portion of the cephalon is characterized by the presence of two sutures and six setae. A suture is found on each side of the distal margin of the cephalon.Each suture is bordered by microtrichs. Two simple setae with a sensory hair, articulated on the base by a socket, are found one on each side of each of the sutures. Two additional setae, similar in shape and size, occur medially on the cephalon. A terminal pore is absent on the sensory hairs of all setae. These setae are suggested to be mechanoreceptors that provide directional sensitivity and enhance the sensibility of turbulent motion, viscosity and changes of hydrostatic pressure.     

Meandering worms: mechanics of undulatory burrowing in muds

Recent work has shown that muddy sediments are elastic solids through which animals extend burrows by fracture, whereas non-cohesive granular sands fluidize around some burrowers. These different mechanical responses are reflected in the morphologies and behaviours of their respective inhabitants. However, Armandia brevis, a mud-burrowing opheliid polychaete, lacks an expansible anterior consistent with fracturing mud, and instead uses undulatory movements similar to those of sandfish lizards that fluidize desert sands. Here, we show that A. brevis neither fractures nor fluidizes sediments, but instead uses a third mechanism, plastically rearranging sediment grains to create a burrow. The curvature of the undulating body fits meander geometry used to describe rivers, and changes in curvature driven by muscle contraction are similar for swimming and burrowing worms, indicating that the same gait is used in both sediments and water. Large calculated friction forces for undulatory burrowers suggest that sediment mechanics affect undulatory and peristaltic burrowers differently; undulatory burrowing may be more effective for small worms that live in sediments not compacted or cohesive enough to extend burrows by fracture.     

The freeliving nematode genus Parodontophora Timm 1963 (Nematoda: Axonolaimidae) is not exclusively marine: Parodontophora limnophila sp. nov. from freshwater in China

Parodontophora limnophila sp. nov. is described from Poyang Lake, the largest freshwater lake of China. It is characterized by having an amphid with its posterior end close to the base of the stoma, relatively short cephalic setae, opisthocephalic setae arranged as two subdorsal groups of three longitudinally arranged setae and two single subventral setae, excretory pore at the level of the anterior part of the stoma and renette gland 34–47% of the oesophageal length. To date, the new species is the only Parodontophora species found in freshwater habitats.     

Development of the pedicle in the articulate brachiopod Terebratalia transversa (Brachiopoda,Terebratulida)

Summary The development of the pedicle in the articulate brachiopod Terebratalia transversa has been examined by electron microscopy. The posterior half of the free-swimming larva comprises a non-ciliated pedicle lobe that contains the primordium of the juvenile pedicle at its distal end. During settlement at five to six days post-fertilization, the pedicle lobe secretes a sticky sheet that attaches the larva to the substratum. As metamorphosis proceeds, the epithelium in the posterior half of the pedicle lobe produces a thin overlying cuticle, and the pedicle primordium develops into a stalk-like anchoring organ. The juvenile pedicle protrudes through the gape that occurs between the posterior margins of the shell valves. A cup-like canopy, called the pedicle capsule, lines the posterior end of the shell and surrounds the newly formed pedicle. The core of the juvenile pedicle is filled with a solid mass of connective tissue. Numerous tonofibrils occur in the pedicle epithelium, and the overlying cuticle consists of amorphous material covered by a thin granular fringe. By one year post-metamorphosis, a body cavity develops anterior to the pedicle. Two pairs of adjustor muscles extend from the posterior end of the shell and traverse the cavity to insert in the pedicle. The connective tissue core of the pedicle in sub-adult specimens lacks muscle cells but contains numerous fibroblasts and collagen fibers. Three regions are recognizable in the connective tissue compartment of the adult pedicle: a subepithelial layer of non-fibrous connective tissue, a central fibrous zone, and a proximal mass of tissue that resembles cartilage.List of abbreviations as adhesive sheet - bc body cavity - bv brachial valve of shell - cf collagen fibrils - ct connective tissue - cu cuticle - di diductor muscle - ec epithelial cell - f fibroblast - fz fibrous zone - g gut - gc granular cell - gd gastric diverticulum - ht hinge tooth - ia interarea of pedicle valve - icl inner cuticular layer - lo lophophore - lu lumen of gut - m mesenchyme - ma mantle - ml mantle lobe - ocl outer cuticular layer - p periostracum - pc pedicle capsule - pce pedicle capsule epithelium - pcl pedicle collar of shell - pcn pedicle connectives - pd pedicle - pe pedicle epithelium - pl pedicle lobe - pv pedicle valve of shell - pzc proximal zone of cartilage-like tissue - s substratum - sel subepithelial layer - t tendon - tf tonofibril - vam ventral adjustor muscle     

寄螨亚科6已知种补充描述（蜱螨亚纲：革螨股）

对短毛寄螨Parasitus brachychaetus Ma,1986;王氏寄螨Parasitus wangdunqingi Ma,1995;二刺寄螨Parasitus bispinatus Ma,1996;北方糙革螨Trachygamasus borealis Ma et Wang,1996;三尖常革螨Vulgarogamasus trifidus Ma,1987和甘肃常革螨Vulgarogamasus gansuensis Ma,1987进行了补充描述。     

维螨属2新种记述(蜱螨亚纲:中气门目:维螨科)

记述维螨属2新种:河南维螨Veigaia henanensis sp.nov.和福建维螨Veigaia fujianensis sp.nov.     

Effects of Copper on the Burrowing Behavior of Estuarine and Coastal Invertebrates,the Polychaete Nereis diversicolor and the Bivalve Scrobicularia plana

Alterations of the burrowing behavior of two benthic invertebrates living in intertidal mudflats, the polychaete Nereis diversicolor and the bivalve Scrobicularia plana, were studied in individuals exposed to soluble copper. The design of the contamination procedure took into account the results assessing the influence of some natural factors potentially able to influence burrowing (artificial vs. natural sediment, lighting, size of the shell for bivalves). Animals were exposed for 4 d to concentrations ranging from 25 to 150 μ g Cu l^{? 1}. At the end of exposure, the burrowing kinetics in clean sediment were determined after 1 and 2 d, then the animals were frozen until acetylcholinesterase (AChE) activity determination. Even at the lowest tested concentrations, copper caused hypoactivity in organisms belonging to both species studied. Behavioral impairments were not related to AChE activity inhibition. Metabolical or physiological disturbances could be the cause of these impairments. Concentrations affecting burrowing behavior were below those responsible for lethality in these species.     

Factors influencing the distribution and feeding of the larvae of Chironomus riparius

Chironomids are the most widely distributed group of insect larvae in freshwater environments. They are frequently the dominant primary consumers and show competitive interactions due to their requirements for foraging space in suitable substrates. In order to investigate the factors involved in substrate selection a simple choice chamber has been constructed that enables larvae of Chironomus ripariusMeigen (Diptera, Chironomidae) to select wells, in which they can establish tubes, according to a number of chemical and physical parameters. The statistical probabilities of them aggregating randomly in this way were calculated for a variety of occupancies. The larvae developed distinct patterns of non-random aggregation in the wells. Subsequent experiments showed that the presence of food at sites of burrowing affected settling but physical irregularities were necessary in order to facilitate burrowing and establish random patterns. Once the animals had selected their habitat the rate of feeding on the sediment was relatively constant with a gut-clearance time of about 12 h although starving the animals before or after feeding affected the rate of passage of sediment through the anterior of the gut.     

Observations on two closely related species, Chaetoceros tetrastichon and C. dadayi (Bacillariophyceae)

Two tropical-subtropical species of the diatom genus Chaetoceros, C. tetrastichon and C. dadayi were studied in light, scanning and transmission electron microscopy, from plankton samples collected in the Gulf of California, off the coasts of Baja California and the Mediterranean Sea. Both species are usually found to be attached to a tintinnid. The basic structure of both species agrees with previous studies of species belonging to the subgenus Phaeoceros , including the finely perforated cell wall of the valves and the presence of one rimoportula in every valve of the cells in the chain, which is located in the centre of the annulus. A clear costae pattern was found in C. tetrastichon , but it is less apparent in C. dadayi. Other differences between the two species are the direction and morphology of the setae, especially the anterior terminal ones, and the number of girdle bands. Questions on the function of the setae in Chaetoceros continue offering matter for speculation.     

中国裸厉螨属1新种和1新记录（蜱螨亚纲：中气门目：厉螨科）

记述裸厉螨属1新种：古蔺裸厉螨Gymnolaelaps gulinensis sp．nov．和1新记录：奥地利裸厉螨Gymnolaelaps austrgacus（Sellnick,1935）。