scholarly journals Shape of attachment structures in parasitic isopodan crustaceans: the influence of attachment site and ontogeny

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e9181 ◽  
Author(s):  
Serita van der Wal ◽  
Joachim T. Haug
Keyword(s):  
Attachment Site ◽  
Morphological Characters ◽  
The Body ◽  
Immature Stages ◽  
Life Stages ◽  
Comprehensive Description ◽  
Additional Species ◽  
Critical Comparison ◽  
Statistical Representation ◽  
Attachment Structures

Many fields of modern systematic biology are adult-centred. This is unfortunately also the case for Cymothoidae, an ingroup of parasitic forms of Isopoda, with fishes as hosts. Different ingroups of Cymothoidae have specialised appendages that enable their fish associated lifestyles, attaching to different sites on the body of the host. The extent to which these structures vary among species and in relation different sites of attachment, and between different ontogenetic stages, is explored here. This study presents the detailed descriptions, illustrations, comparisons, and analysis of a variety of attachment structures of 13 adult and immature specimens representing three major groups Ceratothoa, Elthusa and Anilocra, along with full focus, detailed photographs of all the examined life stages. The three groups exhibit different strategies attaching to mouth, gill and externally, respectively. A statistical representation of the morphology of the dactyli, used for attaching to the host, was performed. This included a critical comparison of 10 additional species documented in literature. This is the first comprehensive description and photographs of specialised appendage morphology of immatures of Ceratothoa, as well as the first detailed micrographs of embryonic stages of Cymothoidae, and the first lateral and ventral views of immature stages of the examined species. Immature specimens possess morphological characters that can be used to distinguish between different species, but cannot be accurately identified based on diagnostic characters of adults. Quantitative analysis indicates that ontogeny plays a major role in the shape of the attachment structures (e.g. dactyli).

Mitochondrial DNA allows the association of life stages to facilitate species recognition and delimitation in Australian stoneflies (Plecoptera : Gripopterygidae : Newmanoperla)

2015 ◽  
Vol 29 (3) ◽  
pp. 223 ◽  
Author(s):  
Julia H. Mynott
Keyword(s):  
Aquatic Ecosystems ◽  
Species Recognition ◽  
Mitochondrial Gene ◽  
Morphological Characters ◽  
Immature Stages ◽  
Life Stages ◽  
Larval Morphology ◽  
Larval Life ◽  
Intraspecific Divergence ◽  
Dichotomous Key

The larvae of stoneflies (Plecoptera) are important indicators for monitoring aquatic ecosystems, but the immature stages of some relevant species have not been described. Here, mitochondrial gene sequences are used to associate the adult and larval life stages for species of Newmanoperla McLellan. This study finds molecular and morphological support for five species, which include the four previously described species (N. exigua, N. hackeri, N. prona and N. thoreyi) and a newly recognised species, N. theischingeri, sp. nov., which is described herein. Molecular divergences between species for the COI fragment had minimum values of 15–18% while the maximum intraspecific divergence was 6–9%, and there was no overlap between species. Morphological characters for distinguishing the larvae of the five species were observed on the femora and included variations in the type of setation present and the area of occurrence. The combination of molecular and morphological methods enabled the larval morphology to be reassessed and has led to the following outcomes: the first formal generic larval description, a newly recognised species, updated descriptions for larvae of all species of Newmanoperla and a dichotomous key to larvae.

Pupal stages of three species of the phytophagous genus Merodon Meigen (Diptera: Syrphidae)

Zootaxa ◽  
2018 ◽  
Vol 4420 (2) ◽  
pp. 229 ◽  
Author(s):  
JELENA PRERADOVIĆ ◽  
ANDRIJANA ANDRIĆ ◽  
SNEŽANA RADENKOVIĆ ◽  
LJILJANA ŠAŠIĆ ZORIĆ ◽  
CELESTE PÉREZ-BAÑÓN ◽  
...  
Keyword(s):  
National Park ◽  
Morphological Characters ◽  
Underground Storage ◽  
Immature Stages ◽  
Additional Species ◽  
The Third ◽  
Field Investigations ◽  
Storage Organs ◽  
First Time ◽  
Scanning Electron

plants, are mostly unknown. All known immature stages of Merodon feed on underground storage organs (bulbs, rhizomes and corms) of geophytes of the families Asparagaceae, Iridaceae and Amaryllidaceae. Of 160 known Merodon species, to date, the pupal stages have been described for only four: M. equestris (Fabricius), M. bombiformis Hull, M. luteihumerus Marcos-García, Vujić & Mengual, and M. geniculatus Strobl. During field investigations in Đerdap National Park, Serbia, Merodon puparia were found in the ground near the bulbs of Ornithogalum umbellatum L. (Asparagaceae). DNA barcoding revealed that they belonged to the species M. aureus Fabricius and M. avidus (Rossi). Analysis of museum material from the Bavarian State Collection of Zoology in Germany revealed the puparium of an additional species, M. rufus Meigen. In our study we provide for the first time descriptions of the puparia of these three Merodon species. The main diagnostic morphological characters of the pupal spiracles and posterior respiratory processes are described using scanning electron microscopy, and cephalopharyngeal skeletons using binocular microscopy. In addition, puparium morphology of M. aureus, M. avidus and M. rufus is compared with known puparia of four other Merodon species and with the third larval stage of M. hurkmansi Marcos-García, Vujić & Mengual. 

Three new species, two new genera, and new family Biphragmosagittidae (Сhaetognatha) from Southwest Pacific Ocean

2011 ◽  
Vol 20 (1) ◽  
pp. 161-173
Author(s):  
A.P. Kassatkina
Keyword(s):  
New Species ◽  
Type Species ◽  
Morphological Characters ◽  
The Body ◽  
New Order ◽  
New Genera ◽  
New Family ◽  
The Family ◽  
Three New Species

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.

scholarly journals Molecular Correlation between Larval, Deutonymph and Adult Stages of the Water Mite Arrenurus (Micruracarus) Novus

Life ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 108
Author(s):  
Pedro María Alarcón-Elbal ◽  
Ricardo García-Jiménez ◽  
María Luisa Peláez ◽  
Jose Luis Horreo ◽  
Antonio G. Valdecasas
Keyword(s):  
Culex Pipiens ◽  
Adult Stage ◽  
Gravid Female ◽  
Morphological Characters ◽  
Species Level ◽  
Life Stages ◽  
Water Mite ◽  
Molecular Correlation ◽  
The Common ◽  
Morphological Transformations

The systematics of many groups of organisms has been based on the adult stage. Morphological transformations that occur during development from the embryonic to the adult stage make it difficult (or impossible) to identify a juvenile (larval) stage in some species. Hydrachnidia (Acari, Actinotrichida, which inhabit mainly continental waters) are characterized by three main active stages—larval, deutonymph and adult—with intermediate dormant stages. Deutonymphs and adults may be identified through diagnostic morphological characters. Larvae that have not been tracked directly from a gravid female are difficult to identify to the species level. In this work, we compared the morphology of five water mite larvae and obtained the molecular sequences of that found on a pupa of the common mosquito Culex (Culex) pipiens with the sequences of 51 adults diagnosed as Arrenurus species and identified the undescribed larvae as Arrenurus (Micruracarus) novus. Further corroborating this finding, adult A. novus was found thriving in the same mosquito habitat. We established the identity of adult and deutonymph A. novus by morphology and by correlating COI and cytB sequences of the water mites at the larval, deutonymph and adult (both male and female) life stages in a particular case of ‘reverse taxonomy’. In addition, we constructed the Arrenuridae phylogeny based on mitochondrial DNA, which supports the idea that three Arrenurus subgenera are ‘natural’: Arrenurus, Megaluracarus and Micruracarus, and the somewhat arbitrary distinction of the species assigned to the subgenus Truncaturus.

The immature stages of Smicridea (Rhyacophylax) gladiator Flint 1978 (Trichoptera: Hydropsychidae), with notes on distribution and bionomics

Zootaxa ◽  
2017 ◽  
Vol 4358 (2) ◽  
pp. 375
Author(s):  
GLEISON ROBSON DESIDÉRIO ◽  
ANA MARIA PES ◽  
NEUSA HAMADA ◽  
JORGE LUIZ NESSIMIAN
Keyword(s):  
Amazon Basin ◽  
New Records ◽  
Brazilian Amazon ◽  
First Record ◽  
Immature Stages ◽  
Life Stages ◽  
State Information ◽  
Amazonas State

Immature stages of many Brazilian Smicridea species remains unknown, and efforts to describe all life stages are required. In this paper, the larva and pupa of Smicridea (Rhyacophylax) gladiator Flint 1978, associated with adults through the metamorphotype method, are described and illustrated. In addition, the known distribution of this species is extended in the Brazilian Amazon Basin with new records from Amazonas state and the first record in Pará state. Information about its bionomics is also provided. 

Steinernema borjomiense n. sp. (Rhabditida: Steinernematidae), a new entomopathogenic nematode from Georgia

Nematology ◽  
2018 ◽  
Vol 20 (7) ◽  
pp. 653-669 ◽  
Author(s):  
Oleg Gorgadze ◽  
Elena Fanelli ◽  
Manana Lortkhipanidze ◽  
Alberto Troccoli ◽  
Medea Burjanadze ◽  
...  
Keyword(s):  
New Species ◽  
18S Rrna ◽  
Entomopathogenic Nematode ◽  
Phylogenetic Analyses ◽  
Tail Length ◽  
Morphological Characters ◽  
18S Rrna Gene ◽  
The Body ◽  
Rrna Gene ◽  
A New Species

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.

scholarly journals II.—Notes on Chondrosteus acipenseroides, Agassiz

1887 ◽  
Vol 4 (6) ◽  
pp. 248-257 ◽  
Author(s):  
R. H. Traquair
Keyword(s):  
The Body ◽  
Transitional Form ◽  
Additional Species ◽  
The Subject

The now well-known Liassic Acipenseroid fish Chondrosteus acipenseroides was named by Agassiz in 1843, but not described by him. It subsequently formed the subject of an elaborate memoir by Sir Philip Grey-Egerton, Bart., in which, besides giving a minute account of the structure of the genus, he named two additional species—C. pachyurus and C. crassior. Putting the results of Sir Philip's investigations as briefly as possible, he maintained that while “in all essential points” Chondrosteus resembled the recent Sturgeon, nevertheless in certain others, and notably in the structure of the opercular and hyoid regions, it constituted a transitional form towards the more ordinary Ganoids. Moreover, the skin of the body presented the same naked condition seen in the recent Polyodon.

Entomophilic nematodes, Diploscapter coronatus and Oscheius tipulae from Afghanistan

Zootaxa ◽  
2021 ◽  
Vol 4926 (3) ◽  
pp. 401-416
Author(s):  
MOHAMMAD HUSSAIN FALAHZADAH ◽  
EBRAHIM SHOKOOHI ◽  
GHOLAM HOSSEIN MORAVEJ ◽  
PHATU WILLIAM MASHELA ◽  
ABDUL KHALID MADADI ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Genetic Distance ◽  
Galleria Mellonella ◽  
Morphological Characters ◽  
Molecular Data ◽  
Soil Samples ◽  
The Body ◽  
Morphometric Data ◽  
Molecular Approaches ◽  
The Relationship

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. 

scholarly journals Reproductive diapause in Nysius huttoni White (Heteroptera Lygaeidae)

2002 ◽  
Vol 55 ◽  
pp. 308-311
Author(s):  
X.Z. He ◽  
Q. Wang ◽  
A. Carpenter
Keyword(s):  
Life Cycle ◽  
Immature Stages ◽  
Life Stages ◽  
Reproductive Diapause ◽  
Entire Life ◽  
Entire Life Cycle ◽  
Adult Females ◽  
Critical Photoperiod

The induction of reproductive diapause of Nysius huttoni was studied in the laboratory at 20 1C and 60 10 RH under a series of photoperiod regimes 168 h 1410 h 1212 h and 1014 h lightdark Reproductive diapause was considered to have occurred if females failed to lay eggs for 50 days after emergence The sensitivity of different life stages to diapauseinducing photoperiods varied When newly emerged females whose immature stages had been reared at 168 h were transferred to 1014 h and 1212 h 467 and 793 of them entered reproductive diapause respectively However when fifth instar nymphs were transferred from 168 h to 1014 h and 1212 h 100 of adult females entered reproductive diapause If the entire life cycle was maintained at 1014 h and 1212 h 667 and 400 of females entered reproductive diapause respectively The critical photoperiod for reproductive diapause was estimated to lie between 1311 h and 135105 h

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