Redescription of the enigmatic jellyfish, Crambionella annandalei (Cnidaria: Scyphozoa) from Indian waters

Author(s):  
Pralaya Ranjan Behera ◽  
M. A. Jishnudev ◽  
Raju Saravanan ◽  
Subal Kumar Roul ◽  
Shubhadeep Ghosh ◽  
...  

AbstractThe catostylid jellyfish, Crambionella annandalei was originally described by Rao (1932) based on a preserved specimen collected from the Andaman Sea. Since then, no detailed taxonomic studies have been conducted and the species is often misidentified. Here, we provide a detailed morphological re-description of C. annandalei from fresh material collected at a variety of locations along the east coast of India. The species can be distinguished from its congeners by a combination of morphological characters, the most important of which are the proportion of terminal club length to oral arm length (0.48 ± 0.031), the proportion of the distal portion of the oral arm to naked proximal portion (7.25 ± 0.268) and the body colour. The occurrence of intra-specific colour variation in fresh specimens was also observed in the present study.

Author(s):  
A. R. Fontaine

The ophiuroid, Ophiocomina nigra, is noted for its variability of colour, a phenomenon most pronounced where the species also has its greatest distribution in depth. Observations have been made on two geographically distinct populations, from the vicinities of Millport and Plymouth. The body colour of the observed animals ranges in a continuously graded series from black to orange-yellow. While both populations exhibit analogous variations, there is a distinct difference in the range and tone of coloration which each displays. It is suggested that this geographical difference is correlated in some degree with differences in colour tone of the substratum. It was observed that the incidence of light-coloured phases in each population increased with increasing depths, and some statistical evidence supports this conclusion. Thus, at least two factors, depth and substratum, may affect the distribution of colour variations in O. nigraIn addition to the variations in general body colour, there are two distinct colour patterns found on the disk. These are probably truly polymorphic and may be of cryptic value.A scheme of colour classification is described which facilitates observations in the field and in the laboratory.


2021 ◽  
Author(s):  
Eduardo Mateos ◽  
Daniel Winkler ◽  
Marta Riutort ◽  
Marta Álvarez-Presas

The correct identification of morphological species is a key task for species richness estimation of any ecosystem. Although body colour is a widely used character identifying European Lepidocyrtus species, recent investigations using molecular data have revealed that species delineation using body colour can result in an underestimation of real species diversity because of the presence of cryptic species. Lepidocyrtus violaceus is a European species characterised by its dark violet body colour. Its wide distribution leads us to suspect that several cryptic species can be present within this morphospecies. Since traditional morphological characters have appeared insufficient for real diversity identification in Lepidocyrtus, new morphological characters were needed in order to describe the cryptic diversity detected by molecular data in this genus. Pseudopores are integumentary structures present in all Lepidocyrtus species, but the distribution of these structures has not been properly described in the genus, as well as in Entomobryioidea overall. In the present work we aimed to analyse whether L. violaceus is a monophyletic entity in Europe. Moreover, we aimed to determine if the position and number of pseudopores on the different parts of the body and appendages is a phylogenetically useful character in the identification of the species or superspecific entities. Fourteen populations of L. violaceus from five European countries, and another 25 Lepidocyrtus species from nine European countries have been studied. In total, 208 specimens have been analysed morphologically and half of them were studied molecularly using sequences of the genes COXII and EF-1α. Molecular data revealed that the widely distributed Lepidocyrtus violaceus morphospecies is a polyphyletic entity in Europe. Between 6 and 12 diferent cryptic species have been detected within this European morphospecies, and only the presence of pseudopores on the basal plate of the fourth abdominal segment has been found to be a promising diagnostic character between them. A common basal pattern of pseudopore distribution has been recognised in the European members of the genus, and also a diferential pattern within each European species group. As a general trend, an increase in the number of pseudopores has been detected from the most basal to the most derived species groups in the phylogeny of the genus in Europe.


ENTOMON ◽  
2019 ◽  
Vol 44 (2) ◽  
pp. 155-160
Author(s):  
Keerthy Vijayan ◽  
R. Sugantha Sakthivel ◽  
T.V. Sajeev

The presence of the body colour polymorphism in the tropical invasive pest giant African snail is reported for the first time from South India. Three different body colour polymorphs were recognised viz. grey, black and white. The grey body colour is the most common polymorph. The black and white colour polymorphs are found to be in almost equal proportions in the reported localities with the grey counterparts. The cytochrome oxidase subunit I (COI) sequences of the three colour polymorphs are found to be identical. The presence of the body colour polymorphism in south India may be attributed to the avian predation and other selection pressures.


2011 ◽  
Vol 20 (1) ◽  
pp. 161-173
Author(s):  
A.P. Kassatkina

Resuming published and own data, a revision of classification of Chaetognatha is presented. The family Sagittidae Claus & Grobben, 1905 is given a rank of subclass, Sagittiones, characterised, in particular, by the presence of two pairs of sac-like gelatinous structures or two pairs of fins. Besides the order Aphragmophora Tokioka, 1965, it contains the new order Biphragmosagittiformes ord. nov., which is a unique group of Chaetognatha with an unusual combination of morphological characters: the transverse muscles present in both the trunk and the tail sections of the body; the seminal vesicles simple, without internal complex compartments; the presence of two pairs of lateral fins. The only family assigned to the new order, Biphragmosagittidae fam. nov., contains two genera. Diagnoses of the two new genera, Biphragmosagitta gen. nov. (type species B. tarasovi sp. nov. and B. angusticephala sp. nov.) and Biphragmofastigata gen. nov. (type species B. fastigata sp. nov.), detailed descriptions and pictures of the three new species are presented.


1969 ◽  
Vol 42 (1) ◽  
pp. 284-295 ◽  
Author(s):  
Allen L. Bell ◽  
David B. Peakall

The ampullate silk gland of the spider, Araneus sericatus, produces the silk fiber for the scaffolding of the web. The fine structure of the various parts of the gland is described. The distal portion of the duct consist of a tube of epithelial cells which appear to secrete a substance which forms the tunica intima of the duct wall. At the proximal end of the duct there is a region of secretory cells. The epithelium of the sac portion contains five morphologically distinct types of granules. The bulk of the synthesis of silk occurs in the tail of the gland, and in this region only a single type of secretory droplet is seen in the epithelium. Protein synthesis can be stimulated by the injection of 1 mg/kg acetylcholine into the body fluids. 10 min after injection, much of the protein stored in the cytoplasm of the epithelial cells has been secreted into the lumen. 20 min after stimulation, the ergastoplasmic sacs form large whorls in the cytoplasm. Protein, similar in electron-opacity to protein found in the lumen, begins to form in that portion of the cytoplasm which is enclosed by the whorls. The limiting membrane of these droplets is formed by ergastoplasmic membranes which lose their ribosomes. No Golgi material has been found in these cells. Protein appears to be manufactured in the cytoplasm of the tail cells in a form which is ready for secretion.


1972 ◽  
Vol 3 (3) ◽  
pp. 181-188 ◽  
Author(s):  
Christine Dahl

AbstractA method for preparation of alcohol-preserved culicid larvae for Scanning Electron Microscope (SEM) studies is described. It is based on dehydration by ethanol-xylol and fast evaporation of xylol in +8o° C. for ten minutes. For taxonomic studies such as examination of pecten teeth, comb scales and microtrichiae in magnifications up to 6oooX the method is suitable. For studies of receptor structures on hair-tufts and microstructures of the body integument alcohol preserved material is less satisfactory. The microstructure of the comb scales is figured and their function discussed. Differences in the ultrastructure of the abdominal hair-tufts are pointed out.


Zootaxa ◽  
2018 ◽  
Vol 4441 (1) ◽  
pp. 137
Author(s):  
JEANNE ROBINSON ◽  
JEREMY GIBSON ◽  
HELBER ADRIÁN ARÉVALO-MALDONADO ◽  
JURATE DE PRINS ◽  
JAMES WINDMILL

Nearly a century ago, wing venation was introduced in gracillariid taxonomy as a means to diagnose closely related genera and species groups. Recent advances in non-destructive virtual micro-dissections suggest promising approaches with which to revisit the relevance of wing venation characters on historic primary type specimens. Many unique type specimens in Gracillariidae and other microlepidoptera groups preserved in museum collections are in poor condition, and over the course of history have suffered loss or damage to their abdomens. Consequently, genitalia morphology is not available for diagnoses and comparisons. In this paper we emphasize the need to include the type species and type specimens into the broader context of taxonomic studies on micro-moths in general and the family Gracillariidae in particular. The genus Caloptilia has a world-wide distribution and has been the subject of research for more than 200 years, yet the generic boundaries and groupings within the genus are still unresolved due to the lack of a reliable set of taxonomic characters obtained from the primary types. We describe a method of virtual descaling of the fore- and hindwings using the unset micro-moth type specimen of Caloptilia stigmatella Fabricius, 1781, in order to demonstrate that the study of historic and fragile type specimens and diagnoses of their internal morphological characters becomes possible by applying new and non-destructive technology. 


Nematology ◽  
2018 ◽  
Vol 20 (7) ◽  
pp. 653-669 ◽  
Author(s):  
Oleg Gorgadze ◽  
Elena Fanelli ◽  
Manana Lortkhipanidze ◽  
Alberto Troccoli ◽  
Medea Burjanadze ◽  
...  

Summary A new species of entomopathogenic nematode, Steinernema borjomiense n. sp., was isolated from the body of the host insect, Oryctes nasicornis (Coleoptera: Scarabaeidae), in Georgia, in the territory of Borjomi-Kharagauli. Morphological characters indicate that the new species is closely related to species of the feltiae-group. The infective juveniles are characterised by the following morphological characters: body length of 879 (777-989) μm, distance between the head and excretory pore = 72 (62-80) μm, pharynx length = 132 (122-142) μm, tail length = 70 (60-80) μm, ratio a = 26.3 (23.0-29.3), H% = 45 (40-51), D% = 54 (47-59), E% = 102 (95-115), and lateral fields consisting of seven ridges (eight incisures) at mid-body. Steinernema borjomiense n. sp. was molecularly characterised by sequencing three ribosomal regions (the ITS, the D2-D3 expansion domains and the 18S rRNA gene) and the mitochondrial COI gene. Phylogenetic analyses revealed that S. borjomiense n. sp. differs from all other known species of Steinernema and is a member of the monticolum-group.


Zootaxa ◽  
2021 ◽  
Vol 4926 (3) ◽  
pp. 401-416
Author(s):  
MOHAMMAD HUSSAIN FALAHZADAH ◽  
EBRAHIM SHOKOOHI ◽  
GHOLAM HOSSEIN MORAVEJ ◽  
PHATU WILLIAM MASHELA ◽  
ABDUL KHALID MADADI ◽  
...  

Several soil samples from different habitats in Badakhshan province of Afghanistan were collected to isolate and characterize bacteria feeding nematodes. The Galleria mellonella-baiting method was used for the isolation of the Afghan insect-associated nematodes. The nematodes were studied using morphological and morphometric data. The Oscheius specimen was characterized by a longer body (630–820 µm) and shorter pharynx (125–145 µm), whereas other morphological characters were not unusual. The Diploscapter specimen had an annulated cuticle, with lip region width 1.5 times shorter than the stoma, and had separated pharyngeal corpus from the isthmus and vulva located in the middle of the body. The molecular data were derived using three loci; 18S, 28S (D2/D3 segment), and ITS rRNA region, which were utilized to measure the genetic distance. The phylogenetic analysis was conducted to reconstruct the relationship tree. Both morphological and molecular approaches confirmed the identity of nematode isolates as Oscheius tipulae and Diploscapter coronatus. This is the first report of insect-associated nematodes from the soil of Afghanistan. Both species were capable of infecting and killing G. mellonella larvae in less than 96 h. 


Zootaxa ◽  
2018 ◽  
Vol 4461 (3) ◽  
pp. 438
Author(s):  
CARLOS AUGUSTO FIGUEIREDO ◽  
CRISTIANO R. MOREIRA

A new species, Poecilia (Pamphorichthys) akroa, is described from the Rio Tocantins drainage, Brazil. The new species differs from the remaining species of the genus by the possession of 10 or 11 pectoral-fin rays, entire preopercular ramus and posterior portion of the supraorbital ramus of the cephalic sensory system enclosed in canals, a faint longitudinal band along the body, a single gonapophysis, a homogeneous reticulate color pattern on sides of body, urogenital region of females heavily pigmented, distalmost segments of the anterior branch (4a) of the fourth gonopodial ray fused into an elongated segment turned anteriorly, subdistal segments of anterior branch (5a) of fifth gonopodial ray simple, without anterior (ventral) projections, dorsal fin with pigmentation at its distal portion and with a basal black blotch, and chromatophores more concentrated on the posterior margin of the mid-ventral scale series of the caudal peduncle and ventrolateral margin of the adjacent scales forming a series of rhombi posterior to anal fin. 


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