Studies on Pogonophora. 4. Fine structure of the cuticle and epidermis

The fine structure of the integument in several species of Pogonophora has been examined by electron microscopy. The cuticle over the main body is composed of several layers of orthogonally arranged fibres embedded in an amorphous matrix. It is regularly traversed by microvilli from underlying epidermal cells. Toothed bristles of the annuli and setae of the anchor are composed of closely packed fibrous cylinders wrapped in a cortical material. In fine structure the cuticle, setae, toothed bristles (or setae) and setal sacs forming the setae closely resemble the corresponding structures in annelids. The cuticle is maximally thick over the forepart (protosome + mesosome) ; it is very thin and non-fibrous over the surface of the metameric papillae and over extensive areas of post-metameric trunk. The possibilities of a collagenous nature of the cuticle fibres and their mode of secretion by the epidermal cells are discussed. The organization of various cell-types forming the epidermis over the entire animal is examined. Possible functions of these cell-types are discussed. Notable amongst these are 'possible zymogen cells' and some absorptive cells. The intriguing question of nutrition in these gut-less tubiculous animals is re-examined in the light of present observations.     

球孢白僵菌在红火蚁体表侵染的扫描电镜观察

利用扫描电镜观察了球孢白僵菌Beauveria bassiana Bb04菌株分生孢子对红火蚁Beauveria bassiana 工蚁体壁的侵染过程。结果表明: 分生孢子多分布在红火蚁工蚁节间膜、胸部的褶皱、气门、体壁的凹陷部位、刚毛窝附近, 以及着生较密刚毛的足上。萌发的分生孢子在节间膜以及体表缝隙、刚毛窝及刚毛稀少的凹陷部位、胸部褶皱和足胫节处入侵。分生孢子在附着12 h后开始萌发, 接种后18 h附着在节间膜处的孢子首先侵入成功, 接种后24 h刚毛窝附近孢子萌发入侵, 接种后60 h胸、腹和足等部位的孢子均成功穿透侵入表皮。分生孢子可以直接以芽管侵入表皮, 也可以产生附着胞再侵入。     

In situ occurrence of a gall midge (Insecta,Diptera, Cecidomyiidae) on fossilized angiosperm leaf cuticle fragments from the Pliocene sediments of eastern India

In situ preservation of fossil insect damage in plant fossils is an excellent tool to study the coevolution of flora and fauna through geological time, but finding both damage and the insect causing that damage in the same specimen is a very rare phenomenon. Galling is a common form of angiosperm leaf damage, which can be regarded as a kind of extended phenotype of the causal insects, essentially the gall midges, but galls usually lack remains of the insects themselves. Here we report the in situ occurrence of a gall midge (Insecta, Diptera, Cecidomyiidae) as well as its pupal exuviae on the abaxial cuticular surface of fossilized leaf cuticle fragments of Fabaceae leaves (cf. Albizia) that also bear galls, recovered from the latest Neogene (Rajdanda Formation, Pliocene) sediments of the Chotonagpur Plateau, Jharkhand, northeastern India. This Pliocene gall midge features well-preserved legs, segmented antenna with distinct and enlarged scape, elongate curved setae, and longer than broad terminal plate of the ovipositor lamellae. The in situ presence of a gall midge on a host fabaceous leaf cuticle indicates the existence of a host-ectoparasite relationship in the ancient warm and humid tropical monsoon-influenced forests of eastern India during the Pliocene. This is the first authentic fossil record of an in situ phytophagous insect of Cecidomyiidae from India, as well as southeast Asia. Although the identification of the recovered phytophagous insect associated with the fossil leaf cuticle is only possible to family level, this find reveals that such plant-insect relationships existed in the Pliocene of eastern India.     

Revising the definition of the crustacean seta and setal classification systems based on examinations of the mouthpart setae of seven species of decapods

The crustacean cuticle has numerous projections and some of these projections, the setae, have important mechanical as well as sensory functions. The setae display a wide diversity in their external morphology, which has led to great problems separating setae from other projections in the cuticle and problems in making a consistent classification system. Here, the cuticular projections on the mouthparts of seven species of decapods are examined by scanning and transmission electron microscopy. A new definition is given: a seta is an elongate projection with a more or less circular base and a continuous lumen; the lumen has a semicircular arrangement of sheath cells basally. From the details of the external morphology the mouthpart setae are divided into seven types: pappose, plumose, serrulate, serrate, papposerrate, simple and cuspidate setae, which are suggested to reflect mechanical functions and not evolutionary history. This classification system is compared with earlier systems.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 142 , 233–252.     

Surface structures and sense organs of the cypris larva of Balanus balanoides as seen by scanning and transmission electron microscopy.

Various features of the settlement stage larva (cyprid) of the barnacle, Balanus balanoides (L.), were studied using scanning and transmission electron microscopy. The cuticle of the valves is pitted and in section has a characteristic ultrastructure. Small sensory setae protrode from the surface of this cuticle and are probably mechanoreceptors able to sense water movement around the larva. Each of the pair of caudla appendages which protrude from between the larval valves posteriorly, is made up of several sensory setae. These appendages are able to sense settlement surface topography. Certain other features of the larva are alos described and their roles discussed; such features include the frontal filaments, antennules and thoracic limbs.     

饲料中转基因成分对家蚕生长发育的影响

采用家蚕（Bombyx mori）H9品种作为实验动物,分别用转基因和非转基因大豆粉制作的人工饲料进行饲育。通过饲育试验,比较分析了不同处理后家蚕的龄期经过时间、全茧量、茧层量、茧层率、蛹体重、疏毛率、死亡率、每龄眠起体重等经济性状指标。同时采用PCR方法对转基因饲料饲育后家蚕组织中外源基因的表达情况进行了检测。结果显示,含转基因大豆粉的人工饲料对家蚕的生长发育并无显著影响,且不存在外源基因的污染。     

中国美绥螨属1新种和大陆1新记录（蜱螨亚纲：中气门目：美绥螨科）

记述中国美绥螨属1新种：拟筐美绥螨Ameroseius imitocorbiculus sp．nov．和大陆1新记录：越南美绥螨Ameroseius vietnamensis Micherdzinski,1955。     

Ecdysteroid Titres and Cuticle Depositions in Embryos of the Dipteran Calliphora erythrocephala

Summary

Before the shortening of the germ band, embryos of Calliphora erythrocephala secrete an electron dense layer which resembles a thin atypical cuticle. After completion of the dorsal closure, a second, typical, cuticle is deposited. It is characterized by a thick procuticle and by the presence of hooked setae. This cuticle develops into the larval cuticle of the first instar.

We did not find in newly-laid eggs of Calliphora detectable amounts of either free or hydrolysable conjugated ecdysteroids. A marked rise in ecdysteroid concentrations, essentially attributable to free ecdysone and 20- hydroxyecdysone, occurs shortly before the deposition of the typical cuticle. After a transient decrease, the ecdysteroid titre rises again before hatching.

When eggs are mid-ligatured at blastula or early gastrula stages, the posterior embryonic half is able to build up a typical cuticle with hooked setae. This cuticulogenesis is therefore not dependent on the presence of the embryonic ring glands.     

中国革螨2新记录（蜱螨亚纲：裂胸螨科，角绥螨科）

报道中国革螨2新记录：半裂北绥螨Arctoseius semiseissus（Berlese,1892）和奥氏角绥螨Antennoseius oudemansi（S．Thor,1930）。     

Evolution of antennules of cytheroidean ostracods (Crustacea)

Phylogenetic analysis and fossil records indicate that antennules with whip-like setae are the most plesiomorphic state in cytheroidean ostracods and that antennulae with claw-like setae are derived from antennulae with whip-like setae. Character distributions on the 18S rDNA molecular phylogenetic tree suggest that two phenotypic features of cytheroidean antennules (W/L ratio and claw-like/whip-like setae) have morphological plasticity. These features have evolved as an ethological adaptation rather than due to phylogenetic constraints such as the evolution of shell outline in cytheroideans. However, the species of the Leptocytheridae–Trachyleberididae clade generally have stout, robust antennules, indicating a phylogenetic constraint. The character state of setae (claw/whip) in cytheroidean ostracods is reflected more through their ethology than the W/L ratio of the antennules. On the basis of the present analysis and the fossil record, diversification in the morphology of the antennules seems to have occurred during the early Mesozoic.     

Three new species of Antricola (Acari: Argasidae) from Brazil, with a key to the known species in the genus

Three new species of Antricola (Acari: Argasidae) are described from adult specimens collected on bat guano in different caves in Brazil. The female of Antricola guglielmonei n. sp. is easily determined by the presence of 2 smooth, depressed areas lacking setae in the posterolateral portions of the dorsum of the idiosoma, together with the partial fusion of the tubercles in the anteromedian portion of the idiosoma. The male of this species has a small spiracular plate surrounded by a pattern of tubercles disposed concentrically in its dorsal portion. Both sexes have cervical grooves very slightly marked. Antricola delacruzi n. sp. represents the only Antricola species with the dorsum of the idiosoma devoid of tubercles in both sexes and with scarce and minute setae placed over the smooth cuticle. The female of A. inexpectata n. sp. is known only from a few specimens. In this species, lines of smooth cuticle lacking setae separate the tubercles of the dorsum. In addition, there are 3 clumps of plumose setae close to the spiracular plate, in the ventrolateral portions of the idiosoma, in 3 well-delimited regions over cuticular thickenings. These 3 species share the peculiarity of a Haller's organ with the anterior pit bearing only 7 + 2 setae. The collection of these new species in Brazilian caves greatly expands the known range of the genus. A key to the adults of all known species of the genus is provided.     

Chemoreception in four species of water mites (Acari: Hydrachnida): behavioural and morphological evidence

Silver nitrate staining of the solenidial and eupathidial sensilla on the palpi, tarsi and tibiae of legs I and II of Arrenurus acutus, Geayia ovata, Mideopsis reelfootensis and Albia caerulea, along with ultrastructural studies, showed that these setae have a porous shaft cuticle. These setae are hollow and contain dendrites in their lumens and more than one neuron is associated with each setae. Behavioural experiments supported the involvement of these sensilla in the perception of chemical cues from prey and sexual partners.     

Antennular sensilla of the brine shrimp, Artemia salina.

1. Scanning electron microscopy was used to characterize the external morphology of setae found on the antennules of adults and nauplii of the brine shrimp, Artemia salina (L.). The permeability of the antennular setae was studied by means of Slifer's crystal violet method. 2. Each antennule of an adult brine shrimp possessed a terminal cluster of sensory setae. Within a cluster there were two morphologically distinct kinds of sensilla, here designated type 1 and type 2. Three type 1 sensilla were observed on every antennule examined. The number of type 2 sensilla per antennule was usually four or five. 3. Type 1 sensilla of adults were 43 to 80 micrometer long and simple in external morphology. They were widest at the base, decreased in diameter gradually, and terminated as a finely tapered tip. No pores were resolved by scanning electron microscopy. 4. Type 2 sensilla of adults were shorter (shaft length, 12 to 23 micrometer) and displayed a single pore at the tip (average pore diameter, 0.4 micrometer). In thin section they were seen to possess a distinctive articular specialization of the cuticle at the base of the seta. 5. Dye penetration experiments indicated that type 2 sensilla were permeable to aqueous crystal violet, whereas type 1 sensilla were not. 6. The antennular setae of nauplii resembled type 1 sensilla in general shape, in being impermeable to crystal violet, and in lacking a terminal pore and basal articular specialization. Moreover, a total of three setae was normally present on each naupliar antennule, and the same number of type 1 sensilla was found on each adult antennule examined. If the three naupliar setae represent a developmental stage in the formation of three adult sensilla, available observations suggest that the larval setae are developmentally related to type 1, rather than to type 2 adult sensilla.     

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）。     

Chemoreception in four species of water mites (Acari: Hydrachnida): behavioural and morphological evidence

Silver nitrate staining of the solenidial and eupathidial sensilla on the palpi, tarsi and tibiae of legs I and II of Arrenurus acutus, Geayia ovata, Mideopsis reelfootensis and Albia caerulea, along with ultrastructural studies, showed that these setae have a porous shaft cuticle. These setae are hollow and contain dendrites in their lumens and more than one neuron is associated with each setae. Behavioural experiments supported the involvement of these sensilla in the perception of chemical cues from prey and sexual partners.     

Cuticular Studies on Two Pleistocene Species of Lauraceae in Baise Basin,Guangxi

Two fossil leaves with cuticle described here were collected from the Pleistocene Changseling Formation of Baise Basin, Guangxi. A detailed comparison of the cuticular analysis between the fossils and their living equivalents indicated that the two fossil species belong to 2 genera of Lauraceae, that is, Alseodaphne of, hainanensis Merr. and Pheobe cf. sheareri (Hemsl.) Gamble. The first report on lauraceous fossil leaves with cuticle in China showed that cuticular analysis had a reliable value in identifying the angiospermous fossil plants.     

论非洲叶肢介科的分类

叶肢介化石生长线下缘锯齿状构造曾作为非洲叶肢介科(Afrograptidae)分类的主要特征,通过扫描图像,从比较解剖学研究入手,揭示了现生与化石叶肢介壳瓣的锯齿构造是由于分布于生长线的一排刚毛,基部关节脱落而形成的;分析了生长线刚毛的形态是属于长针形的轴刚毛,主要司触角功能;在5科18属现生叶肢介中,至少3科7属32种具有生长线刚毛,22属化石叶肢介有锯齿构造;作者认为这一构造被视为非洲叶肢介科分类的主要依据是不合适的,壳瓣的放射褶或粗瘤构造在高级分类上更重要,进而对该科的含义进行了厘定;从壳瓣具有多条放射褶这一构造特征来看,它与小叶肢介超科(Estheriellioidea)的成员在发生关系上比较密切,小叶肢介超科可提升为亚目(Estheriellidea),包括小叶肢介超科和非洲叶肢介超科,是中生代初兴起的一个类群。在白垩纪中期消失。     

广西百色盆地更新世樟科两种植物角质层研究

本文描述的具角质层的两块叶化石,产自广西百色盆地更新统长蛇岭组。经与现代植物的角质层对比研究后,确定这两块叶化石分属于樟科的两属两种,即油丹(近似种)(Alseoda-phne cf.hainanensis Merr.)和紫楠(近似种)[Phoebe cf.sheareri(Hemsl.)Gamble]。研究结果表明,角质层在鉴定被子植物化石中具有可靠的价值。     

Cytology of various antennal setae in a troglobitic Mysidacea (Crustacea)

Summary The various antennal setae can be differentiated from each other by the number and the type of their dendrites and by the cuticular structure of their external parts; these features correspond to functional differences. Moreover, the work revealed differences in relation to the corresponding setae of a marine Mysidacea previously studied by Guse (1978). Various hypotheses linking the ultrastructural differences to those that characterize the environments in which these two species live can be put forward.Abbreviations A1, A3 simple setae A1, A3 - An antenna - B1, B2 setulate setae B1, B2 - Bi bifid seta - bp bending plane - c1, c2, c3 type 1, 2, or 3 cilia (outer dendritic segments) - cu cuticle - d1, d2, d3 type 1, 2, or 3 dendrites (inner dendritic segments) - ec enveloping cell - g Golgi apparatus - h helically arranged cuticle - md microtubule doublet - n nucleus - p apical pore - r ciliary root - s setules - sc scolopale - scc scolopale cell - Si sickle-shaped seta - sm small seta - st stopper - t extracellular matter tube