Speciation,phenotypic plasticity,or ontogeny,the case of the genus Galkinius (Pyrgomatidae,Cirripedia, Crustacea)

Barnacles of the genus Galkinius occupy a large spectrum of host corals, making it one of the least host‐specific genera within the Pyrgomatidae. Molecular analyses show that within the genus Galkinius there are highly supported clades, suggesting that the genus Galkinius is a complex of evolutionarily significant units (ESUs). The morphology of the opercular valves has been used as the basis for the separation of species of Galkinius. In this study, morphological variability was found both between specimens within ESUs extracted from different host species and between specimens extracted from the same colony. Identifications based on the opercular valves cannot therefore be assigned to different species despite being genetically distinguishable. It is proposed that in many cases the differences between valve morphology of different species of Galkinius are the outcome of ontogeny. Allometric growth of the valves has resulted in differences in the proportions of the parts of the valve. © 2015 The Linnean Society of London     

介形类Denticulocythere和Potamocythere在柴达木盆地晚新生代地层中的发现——对区内Leucocythere属的再鉴定

本文对区内晚新生代地层中被归入Leucocythere属名下、以L.mirabilis为代表的所有已知种进行了重新审视,发现它们具有一个共同的特征:右壳铰合构造有发育良好的前铰齿.这一特征与以L.mirabilis为模式种的Leucocythere属的属征不一致.这些种的左壳铰棒呈现两种类型:一种具锯齿或刻痕,另一种则...     

New fossil fruits of Carya (Juglandaceae) from the latest Miocene to earliest Pliocene in Tennessee,eastern United States

Fossil fruits including nuts and associated husk valves of a new species of Carya (Juglandaceae) are described from the latest Miocene to earliest Pliocene in northeastern Tennessee, eastern United States. The husk valves are elliptic, 1.2–4.5 mm thick, with a convex exterior face and a concave interior face; the nuts are globose to ovoid in shape, smooth and longitudinally ribbed on exterior surface, with a short protruding apex and a slightly 4-angled base; inner ribs, lacunae and primary septa are well-developed, while secondary septa are absent or weakly developed. The combination of these carpological characteristics clearly shows a close resemblance to the genus Carya in Juglandaceae. Detailed comparisons of carpological morphology and anatomy indicate that the present fossil taxon is different from both living and most other fossil species of the genus, and therefore warrants the designation of a new fossil species, Carya tennesseensis Huang et al., sp. nov. Carya tennesseensis displays a carpological similarity to C. ventricosa from the late Oligocene to early Pliocene in Europe, suggesting a potential species exchange of the genus between Europe and southeastern North America during the late Neogene. The new fossil species represents one of the few fruit fossil species of Carya from its modern distribution range in southeastern North America. It provides crucial information for better understanding the rapid diversification of the genus from the late Miocene to early Pliocene, and the origin and establishment of today's Carya biodiversity in this region.     

OBSERVATIONS ON CHAETOCEROS BUCEROS (BACILLARIOPHYCEAE), A RARE TROPICAL PLANKTONIC SPECIES COLLECTED FROM THE MEXICAN PACIFIC1

Examination of net plankton samples from the Gulf of Tehuantepec (Mexican Pacific) yielded a rare tropical species of the genus Chaetoceros, C. buceros Karsten. This species is conspicuous because of its relatively large size, type of chain formation, and shape of the terminal setae. Electron microscopic study revealed other interesting characteristics: the intercalary values are more lightly silicified than the terminal valves and show a pattern of costae radiating form the center with various annuli (“central hyaline fields”) in the center of the valve face; both kind of valves are perforated by small poroids. Terminal valves possess several (21–30) slitlike and randomly oriented rimoportulae. Important morphological differences exist between the intercalary and the terminal setae. Morphological characters, comparision with related species, and the systematic position are discussed. A new section of the subgenus Hyalochaete, Conspicua, is proposed to include C. buceros.     

A NEW KIND OF SEXUAL DIMORPHISM IN ORDOVICIAN OSTRACODES

Abstract:  In Ordovician ostracodes (genus Incisua ) a new kind of sexual dimorphism is described, which is the first example among this group with males being the heteromorphs. The valves of males are larger and less frequent than the females, and are characterized by having a furrow in the ventral part. The furrow may have functioned as a device to enable the two sexes to cling together during mating.     

MORPHOLOGICAL VARIATION,SPECIES CONCEPTS,AND CLASSIFICATION OF AN UNUSUAL FOSSIL CENTRIC DIATOM (BACILLARIOPHYTA) FROM WESTERN NORTH AMERICA1

The classification system of diatoms (Bacillariophyta) is based almost entirely on the organization and structure of their silica cell walls. We have discovered Miocene freshwater fossils that contain valves of two different orders within the same organism. Within frustules of the genus Ellerbeckia Crawford, a genus of the order Melosirales, are contained frustules of the genus Actinocyclus Ehrenberg, a member of the Coscinodiscales. Based on the abundance of each morphotype, they appear to be able to reproduce themselves. The ability of a single diatom taxon to express this degree of morphological variability is unprecedented. These results suggest species concepts in diatoms may be in need of review and challenge the basis of the classification system for this widely distributed and ecologically important group of organisms.     

Extra-intestinal localization of Goussia sp. (Apicomplexa) oocysts in Rana dalmatina (Anura: Ranidae), and the fate of infection after metamorphosis

Although coccidia of the genus Goussia are common parasites of fish, only 2 species have been described in amphibians: G. hyperolisi from common reed frogs Hyperolius viridiflavus from Kenya and G. neglecta from unspecified European water frogs of the genus Rana from Germany. The genus Goussia is characterized by an oocyst, with a fine oocyst wall, containing 4 dizoic sporocysts that are composed of 2 valves joined by a longitudinal suture and lacking a Stieda body (typical for the genus Eimeria). To date, infections in amphibians were generally considered to be specific to the intestine of aquatic larval stages (tadpoles) of anurans. Herein, we report on: (1) the presence of oocysts of Goussia sp. in an extra-intestinal location (liver) of tadpoles of the agile frog R. dalmatina and (2) the presence of oocysts in the liver of both juvenile and subadult R. dalmatina. These observations represent novel traits for Goussia infections in amphibians; they may explain the vertical transmission of Goussia in tadpoles.     

PSEUDO-NITZSCHIA AS A GENUS DISTINCT FROM NITZSCHIA (BACILLARIOPHYCEAE)1

Morphologic, diagnostic characters of the subgenus Nitzschia, genus Nitzschia Hassall 1845, and the marine planktonic genus Pseudo-nitzschia H. Peragallo in H. & M. Peragallo 1900 were compared. Colony formation by overlap of cell ends; weakly silicified, shallow, and flattened valves; an extremely eccentric raphe, not elevated above the general level of the valve; lack of con-opea; and striated girdle bands characterize Pseudo-nitzschia as a natural group and a genus separate from Nitzschia.     

MIDDLE JURASSIC CEMENTED PECTINIDS AND THE MISSING RIGHT VALVES OF EOPECTEN

Large cemented bivalves, previously regarded as oysters, encrustMiddle Jurassic hardgrounds in Southern England, Normandy andBurgundy. Well preserved specimens show auricles and a largeanterior byssal notch indicating that they are, in fact, theright valves of pectinids, apparently assignable to the genusEopecten Douvillé, 1897. Specimens removed from the substratedemonstrate that a prolonged early byssally-attached stage wasfollowed by attachment by cementation. Previously, the lifehabit of Eopecien has been regarded as enigmatic, interpretationshaving been hampered by the museum record of Eopecten whichis remarkably poor in large right valves. Our specimens suggestthat facultative cementation of adults may have been a commonhabit in the genus. (Received 7 May 1992; accepted 30 June 1992)     

Anatomy and histology of salivary glands of Triatominae]

Histological studies upon the salivary glands of ten species of triatomine bugs were performed looking for their number and structural organization in different genera. It was possible to evaluate the celular epithelium type of each gland, as well as the merocrine and apocrine secretions of the glands. Secretion run until the hilo and after to salivary pump and hypofaringe. The glandular components, D1, D2 and D3 are always present in the Triatoma, Panstrongylus and Diptelogaster but in Rhodnius there are only the first two pairs of glands. The salivary channels and the hilo are analyzed by histology. The whole pair D3 has a clear valve that regularizes the exit of the secretions to the hilo. According to the genus the valves appear in different locations. They have low and dense epithelium, and their nucleus are rich in chromatin. The secondary channels leaving these valves, are very different, with clear chitinous ringer, low level of chromatin in the nucleus and homogeneous cytoplasm.     

PHYLOGENETIC RELATIONSHIPS OF SCOTUSSA AND LEIOTETTIX (ORTHOPTERA: ACRIDIDAE)

Abstract— A cladistic analysis of the South American grasshopper genera Scotussa and Leiotettix was performed in order to test the monophyly of these genera. Eurotettix, Chlorus and the Dichroplus bergi species group were included as terminal taxa. The genus Atrachelacris was used to root the tree. Twenty-nine characters from external morphology, male genitalia and female ovipositor were used in the analysis. In order to test for association between the structural change that occurred in the ovipositor valves of Scotussa and the functional change of the oviposition habits, the data matrix was partitioned and two analyses were performed. Characters from the female ovipositor were excluded from the data set used in the first analysis and another analysis was performed where all the characters were included in the analysis. Information on oviposition habits was then mapped on the cladogram, to determine the transformation for performance. Both analyses yielded only one most parsimonious tree and produced congruent results, confirming the monophyly of Leiotettix and Scotussa and corroborating their close relationship. Characters from the female ovipositor valves were informative not only at the species level but also at higher levels in the cladogram. The results also support the hypothesis of association between the structural change that occurred in the ovipositor valves of Scotussa with the functional change in the oviposition habits. However, this association did not seem to be correlated with the adaptive radiation in the genus.     

一种硅藻中国新记录属种——科氏杜氏藻

科氏杜氏藻是一种泥生或附沙生硅藻。该文对最近刚确立的一个硅藻属——杜氏藻属进行了介绍,利用光学和扫描电子显微镜对2019年4月20日采自东洞庭湖国家级自然保护区的科氏杜氏藻标本进行了观察研究。结果表明该标本具有以下主要形态特征:(1)壳面椭圆披针形。(2)中央区为蝴蝶结形,没有延伸至壳缘。(3)线纹在壳面大部分区域呈辐射状排列,在两端近平行排列,中部线纹密度20~22条/10μm。(4)孔纹圆形或近圆形,在内壳面被圆顶状的孔膜覆盖。(5)在壳面两端存在假隔片。该文调查采集的科氏杜氏藻种群的形态特征与模式种群相吻合,该属在中国是首次报道,为中国新记录属。     

The oldest Lingulids of the Siberian Platform: Microornamentation and shell structure

New brachiopod genus of the order Lingulida Sukharilingula with new type species S. luchininae is described from the Lower Botomian (Lower Cambrian) of northwestern Siberian Platform, basin of the Yenisei River, section on the Sukharikha River. The study of the microornamentation and shell structure of the new genus revealed that the initial shell structure of lingulid shells could transform in the course of early diagenesis. The importance of reconstruction of burial conditions of the valves for the reconstruction of posthumous transformations is discussed.     

Glands, muscles and genitalia. Morphological and phylogenetic implications of histological characters in the male genitalia of Fritillary butterflies (Lepidoptera: Nymphalidae: Argynnini)

The histology and internal morphology of the male valve in a broad sample of Fritillary butterflies are examined. A large internal ridge to which the extensor of the valve muscle fastens is probably an autapomorphy for the tribe Argynnini. A large glandular pocket is found in the valves of all examined Heliconiinae, but is missing in other examined Nymphalidae. The pocket shows considerable variation between the higher taxa. In the higher Fritillaries (subtribe Argynnina) the pocket probably has an effective closing mechanism allowing the male to store a considerable amount of glandular secretion. It has earlier been suggested that the secreta from the pocket glands are transferred to the female during copulation, where they probably have an antiaphrodisiac effect, preventing other males from mating a once mated female. All examined male Fritillaries also have glands in the anellus, the terminal membrane between the valves. In Boloria these glands are extremely well developed and abundant, a condition that is probably an autapomorphy for that genus. The obtained characters are tested against a known phylogeny of the tribe Argynnini.     

Two new species of the genus <Emphasis Type="Italic">Leptochiton</Emphasis> (Mollusca,Polyplacophora) from north-western Pacific

Two new species of the genus Leptochiton, L. сommandorensis sp. nov. and L. incubatus sp. nov. from north-western Pacific are described. Leptochiton сommandorensis differs from the congeners in having radial rows of granules in the lateral areas of intermediate valves, unicuspid dental cap on major lateral teeth of the radula, and dorsal scales with two ribs. Leptochiton incubatus differs from the congeners in having one aesthete pore in each granule, a shallow depression between the central and lateral areas of intermediate valves and between the antemucronal and postmucronal areas of the tail valve, and unicuspid head of major lateral teeth of radula. This species is brooding.     

<Emphasis Type="Italic">Argutostrea</Emphasis> gen. nov.: Questions of taxonomy and ethology of Middle–Late Jurassic epibiont oysters (Bivalvia,Ostreoidea)

Morphology and ethology of the Middle–Late Jurassic oyster “Liostrea” roemeri (Quenstedt) from the Upper Callovian of the Volga Region near Saratov and Middle Volgian of the Subpolar Urals are considered. The inverted shell shape and presence of a beaked umbo on the right valves allow the assignment of these oysters to a new monotypic genus, Argutostrea Kosenko, gen. nov. Features of the internal valve structure examined in only one specimen suggest that the new genus should tentatively be included in the subfamily Pycnodonteinae Stenzel, 1959 of the family Gryphaeidae Vialov, 1936. It is shown that shell morphology of the oyster A. roemeri is connected with transition to dwelling on floating ammonites.     

Distribution of phlebotomine sandflies, of the subgenus Larroussius, in Morocco

Adult sandflies (Diptera: Psychodidae) of the genus Phlebotomus and of the subgenus Larroussius were collected with sticky traps from thirty-four localities in central and south-western Morocco. Four Larroussius species were present in this area, Phlebotomus perniciosus Newstead, being the most widespread and abundant species particularly in the mountainous area, was sympatric with the closely related species Phlebotomus longicuspis Nitzulescu. Only one male of P. perniciosus displayed the bifid copulatory valves characteristic of the species. All specimens showed copulatory valves curved at their apex. The number of coxite hairs is a taxonomical tool that differentiates this morph of P. perniciosus from P. longicuspis. Phlebotomus ariasi Tonnoir was collected from six mountainous stations. Phlebotomus mariae Rioux et al. was scarce; only five males were collected and were often associated with P. ariasi.     

Unicapsula seriolae n. sp. (Myxosporea,Multivalvulida) from Australian Yellowtail Kingfish Seriola lalandi1

Unicapsula seriolae n. sp. forms long plasmodia within the striated muscle fibers of Seriola lalandi off eastern Australia. Its spores are composed of three valves, only one of which contains a developed polar capsule. Within the capsule, the filament makes 2 1/2–3 turns, and this criterion can be used to separate U. seriolae from the two other members of the genus. The flesh of infected fish disintegrates during slow cooking.     

Andinodesma radicostata n. gen. n. sp., a grammysiid taxon from the Lower Devonian Catavi-Formation (Bolivia) and its autecological and phylogenetic implications

Andinodesma radicostata from the lowermost Devonian Cata vi Formation of Bolivia is a grammysiid genus, which is radially ribbed on the central parts of its valves and which exhibits a rather elongate anterior end. The umbones are placed near the middle of the valves and suggest an evolutionary state by Lower Devonian times, that rather parallels trends inGrammysia de Verneuil than in the morphologically closer relatedGrammysioidea Williams & Breger. Thus, the idea is supported, that not all taxa, beingGrammysia-shaped except for the conspicuous “cinctures” may easily be assigned toGrammysioidea. Living in an unstable shifting substratumA. radicostata evolved features that display a compromise between adaptation to free and relatively rapid burrowing and physical shell stabilization. The pattern of ornamentation suggests thatA. radicostata changed its mode of penetrating the sediment during one burrowing act. Anteriorly situated concentric ridges aided in more or less vertical down-probing during an initial phase of penetration whereas the radially ribbed central part of the valves indicates that rocking and forward movement predominated in later stages.