Morphological diversity of stylets in Kolhymorbis (Mollusca: Pulmonata: Segmentinidae)

2017 ◽  
Vol 26 (2) ◽  
pp. 215-222
Author(s):  
E.V. Soldatenko

The taxonomy of freshwater pulmonates (Hygrophila) relies heavily on morphology of their reproductive system, most notably on the characters of the copulatory apparatus. For this reason, taxonomically important components of the copulatory apparatus such as penial stylets have always received much attention in the morphological studies on Hygrophila. The present study describes the stylets of Kolhymorbis bogatovi Zatrawkin et Moskvicheva in Zatrawkin, 1985 and K. shadini Starobogatov et Streletzkaja, 1967 and compares them with the previously described stylet of K. angarensis (Dybowski et Grochmalicki, 1925). The lengths of the stylets vary within the genus from 20 to 30 μm. In K. bogatovi, the stylet is a trough-shaped plate with a distal portion twisted 110° counterclockwise with respect to the proximal portion. The stylet of K. shadini is also a trough-shaped plate, but its walls are curved in such a way that the stylet forms a hollow cone with a beveled tip. The slit between the opposite lateral flanks of the stylet is wide proximally, but narrows down distally. The stylets of all three Kolhymorbis species differ markedly in their shape. The trough-shaped stylet of K. angarensis most likely represents the plesiomorphic state; the stylet of K. bogatovi may have originated from this type of stylet by increasing the curvature of the walls and counterclockwise twisting of the distal portion of the stylet. The cone-shaped stylet of K. shadini may have evolved from the plesiomorphic type by widening of the proximal portion and by even more pronounced curving of the walls throughout the length of the stylet without distal twisting. The penial stylets of Kolhymorbis species are compared with those of Palaearctic genera of the family Segmentinidae Baker, 1945 and the taxonomic utility of the stylet characters is evaluated.

Zootaxa ◽  
2021 ◽  
Vol 4903 (2) ◽  
pp. 285-295
Author(s):  
CARLOS A. M. MARTINS ◽  
WHANDENSON M. DO NASCIMENTO ◽  
LIVANIO C. DOS SANTOS ◽  
CÉLIO MAGALHÃES ◽  
ALLYSSON P. PINHEIRO

A new species of pseudothelphusid crab of the tribe Kingsleyini Ortmann, 1897, from the southern Amazon region in the state of Rondônia, Brazil, is described and illustrated. Fredius avilai n. sp. can be readily distinguished from its congeners by the following characters of the male first gonopod: mesial lobe elongated, convoluted, proximal portion directed laterally, distal portion sharply recurved in abdominal direction; marginal process rounded, not projected over distal opening of spermatic channel, merging with distal portion of abdominal surface after a shallow depression; lateral suture well demarcated along mesoabdominal surface of stem, distal portion directed inwards. The assignment of the new species to the genus Fredius Pretzmann, 1967 and its affinities with another closed related species are discussed. 


2009 ◽  
Vol 18 (1) ◽  
pp. 11-16
Author(s):  
E.V. Soldatenko ◽  
A.A. Petrov

The morphology of the copulatory apparatus and associated cuticular structures in Planorbis planorbis was studied by light microscopy, SEM, TEM and confocal laser scanning microscopy. The significance of these cuticular structures for the taxonomic status of the species and for the systematics of the family Planorbidae in general is discussed.


1955 ◽  
Vol 87 (9) ◽  
pp. 382-399 ◽  
Author(s):  
I. Rivard

In studies of sawflies, the family Pamphiliidae has been much neglected especially from the morphological stand point. Yuasa (1922) made a study of the larvae, but the genus Cephalcia was dealt with rather briefly. Ross (1937) and Benson (1945) made comparative morphological studies of the adults and showed the phylogenetic position of the family. More recently, Middlekauff (1953) published a description of Cephalcia marginata, a pine web-spinning sawfly which was the subject of the present study.


Paleobiology ◽  
2016 ◽  
Vol 43 (1) ◽  
pp. 68-84 ◽  
Author(s):  
Bradley Deline ◽  
William I. Ausich

AbstractA priori choices in the detail and breadth of a study are important in addressing scientific hypotheses. In particular, choices in the number and type of characters can greatly influence the results in studies of morphological diversity. A new character suite was constructed to examine trends in the disparity of early Paleozoic crinoids. Character-based rarefaction analysis indicated that a small subset of these characters (~20% of the complete data set) could be used to capture most of the properties of the entire data set in analyses of crinoids as a whole, noncamerate crinoids, and to a lesser extent camerate crinoids. This pattern may be the result of the covariance between characters and the characterization of rare morphologies that are not represented in the primary axes in morphospace. Shifting emphasis on different body regions (oral system, calyx, periproct system, and pelma) also influenced estimates of relative disparity between subclasses of crinoids. Given these results, morphological studies should include a pilot analysis to better examine the amount and type of data needed to address specific scientific hypotheses.


2015 ◽  
Author(s):  
Sive Finlay ◽  
Natalie Cooper

Morphological diversity is often studied qualitatively. However, to truly understand the evolution of exceptional diversity, it is important to take a quantitative approach instead of relying on subjective, qualitative assessments. Here, we present a quantitative analysis of morphological diversity in a Family of small mammals, the tenrecs (Afrosoricida, Tenrecidae). Tenrecs are often cited as an example of an exceptionally morphologically diverse group. However, this assumption has not been tested quantitatively. We use geometric morphometric analyses of skull shape to test whether tenrecs are more morphologically diverse than their closest relatives, the golden moles (Afrosoricida, Chrysochloridae). Tenrecs occupy a wider range of ecological niches than golden moles so we predict that they will be more morphologically diverse. Contrary to our expectations, We find that tenrec skulls are only more morphologically diverse than golden moles when measured in lateral view. Furthermore, similarities among the species-rich Microgale tenrec Genus appear to mask higher morphological diversity in the rest of the Family. These results reveal new insights into the morphological diversity of tenrecs and highlight the importance of using quantitative methods to test qualitative assumptions about patterns of morphological diversity.


Zootaxa ◽  
2018 ◽  
Vol 4444 (4) ◽  
pp. 437 ◽  
Author(s):  
DMITRY SIDOROV ◽  
ZHONGE HOU ◽  
BORIS SKET

Three new species of the family Gammaridae—Gammarus troglomorphus, sp. n., G. parvioculatus, sp. n. from Lebap Province of Turkmenistan and Tadzocrangonyx alaicus, sp. n. from Batken Region of Kyrgyzstan are described and illustrated. Morphological studies of a closely related Turkmenistan population of G. cf. subaequalis-Garlyk, probably conspecific with Gammarus subaequalis Martynov, 1935 was provided. The affinity of new species to concerned taxa is discussed. To define phylogenetic position of mentioned species DNA barcode data are obtained. Gammarus troglomorphus and G. parvioculatus are close neighbors but exceedingly different morphologically. Gammarus troglomorphus is a troglobiont; G. parvioculatus is an eutroglophile, but with exception of slightly smaller eyes, not troglomorph. Both found only within small areas in the extreme East of Turkmenistan. Gammarus cf. subaequalis-Garlyk seems to extend from the same region far into the eastern Kyrgyzstan. 


Zootaxa ◽  
2021 ◽  
Vol 4992 (1) ◽  
pp. 1-89
Author(s):  
ADRIAN ARDILA-CAMACHO ◽  
CALEB CALIFRE MARTINS ◽  
ULRIKE ASPÖCK ◽  
ATILANO CONTRERAS-RAMOS

Adult external morphology of the extant raptorial Mantispoidea (Insecta: Neuroptera: Mantispidae and Rhachiberothidae) is compared emphasizing the morphology of the subfamily Symphrasinae as a key group to understand the phylogenetic relationships among the members of the superfamily. Plega dactylota Rehn, 1939 is thoroughly characterized in order to exemplify the morphology of the Symphrasinae. Additionally, following a review of the literature and examination of comparative material of Dilaridae, Berothidae, Rhachiberothidae and all Mantispidae subfamilies, a new interpretation of the components of the raptorial apparatus (i.e., head, prothorax, grasping forelegs, as well as integumentary specializations) is presented. Also, wing venation for these groups is reinterpreted, and new homology hypotheses for wing venation are proposed based on tracheation and comparative analyses. Given the high morphological divergence on the genital sclerites within the Mantispoidea, plus the confusing previous usage of neutral terminology and terms referring to appendages across taxonomic and morphological studies, we attempt to standardize, simplify, and situate terminology in an evolutionary context under the “gonocoxite concept” (multi-coxopod hypothesis). The remarkable morphological similarity of the genital sclerites of Symphrasinae and Rhachiberothidae (sensu U. Aspöck & Mansell 1994) with the Nallachinae (Dilaridae) was taken as a starting point to understand the morphology of other Mantispidae subfamilies. Based on these morphological comparisons, we provide a revised phylogenetic analysis of Mantispoidea. This new phylogenetic analysis supports a sister group relationship between the family Rhachiberothidae, comprising Rhachiberothinae and Symphrasinae, and the family Mantispidae, including the subfamily Mantispinae and its sister taxa Drepanicinae and Calomantispinae, which may represent a single subfamily. Based on these analyses, raptorial condition probably evolved a single time in these insects and subsequently became diversified in the two sister clades of the raptorial Mantispoidea.  


2009 ◽  
Vol 34 (3) ◽  
pp. 443-454 ◽  
Author(s):  
Dietmar Quandt ◽  
Sanna Huttunen ◽  
Ray Tangney ◽  
Michael Stech

Although the Lembophyllaceae has undergone considerable revision during the last century, the generic and familial level relationships of this pleurocarpous moss family are still poorly understood. To address this problem, a generic revision of the Lembophyllaceae based on molecular data was undertaken. We analyzed two plastid markers, the trnL-trnF and the psbT-psbH region in combination with the ITS2 of nuclear ribosomal DNA. The molecular data reveal that the current circumscription of the family is too narrow and that several genera previously placed in the Lembophyllaceae should be reincluded. The family includes: Bestia, Camptochaete, Dolichomitra, Dolichomitriopsis, Fallaciella, Fifea, Isothecium, Lembophyllum, Looseria stat. nov., Pilotrichella, Rigodium, Tripterocladium, and Weymouthia. Looseria contains a single species: Looseria orbiculata comb. nov. Acrocladium is excluded and provisionally accommodated in the Lepyrodontaceae. Generic limits supported by the molecular data support a return to the early twentieth century family concept of Brotherus. The analyses indicate that the segregate genus Orthostichella is distinct from its parent genus Pilotrichella, probably at the family level. Whereas Pilotrichella is resolved within the Lembophyllaceae, Orthostichella clusters with Porotrichum and Porothamnium forming a clade (OPP-clade) sister to the remaining Neckeraceae and Lembophyllaceae. Hence, the Neckeraceae is paraphyletic. Recognition of the OPP-clade as a new family is desirable but awaits the results of detailed ongoing morphological studies.


1929 ◽  
Vol 20 (2) ◽  
pp. 209-224 ◽  
Author(s):  
F. G. Sarel-Whitfield

The Sudan dura (millet) bug, Agonoscelis versicolor, F., a member of the family Pentatomidae, Hemiptera Heteroptera (Rhynchota), is an important pest of millet. Its depredations vary from year to year, depending chiefly upon the rainy season, but every few years it causes serious losses of millet (Sorghum vulġare and Sorghum sp.), which is the main food crop of the Northern Sudan.This bug is widely distributed in Africa, but so far as the writer is aware, it is only in the Sudan that it occurs as a serious pest of grain, or, indeed, as a serious pest at all. In view of this, and the little work that has been done upon it, it was felt advisable, when a severe outbreak took place in 1927, not only to concentrate upon the control but also to effect as complete a study as possible of the bionomics and essential morphology of the bug.Upon completion of the work it was found better to publish the results as two separate papers : (1) A Sudan Government Entomological Bulletin, giving an account of the bug as a pest in the Sudan, the control measures carried out, the bionomics and parasites ; and (2) a paper for publication in a scientific journal giving the results of the morphological studies, and their relation and application to the bionomics of the insect. The present paper is the result of the latter study.


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