Molecular phylogeny informs generic and subgeneric concepts in the Schizoptera Fieber genus group (Heteroptera : Schizopteridae) and reveals multiple origins of female-specific elytra

2017 ◽  
Vol 31 (2) ◽  
pp. 191 ◽  
Author(s):  
S. Leon ◽  
C. Weirauch

Wing dimorphism occurs in many genera of Schizopteridae Reuter, 1891 and other litter bugs (Heteroptera:Dipsocoromorpha), in both males and females. In the largest litter bug genus, Schizoptera Fieber, and closely related taxa, sexual wing dimorphism is observed in several species whereby males are macropterous, but females possess elytra, or hardened forewings – a feature that is rare outside of beetles and that we here refer to as female-specific elytra. Phylogenetic hypotheses for Schizoptera are unavailable, but are essential to reveal if female-specific elytra evolved once or multiple times within the genus and to test if the presence of elytra can reverse states to macropterous wings. In addition, generic and subgeneric concepts of this speciose genus-group have not been tested in a phylogenetic framework, and relationships with other schizopterid genera remain largely unknown. Our molecular phylogeny of Schizoptera and related genera documents that this genus is currently polyphyletic, and we raise the subgenus Kophaegis to generic rank to render Schizoptera monophyletic (Orthorhagus was recently elevated to genus). Relationships within Schizoptera reveal several well supported clades, some of them corresponding to currently recognised subgenera. To examine the value of previously used diagnostic features, we optimise 11 morphological characters on the molecular phylogeny and update generic and subgeneric diagnoses. Tracing transitions between macropterous and elytrous wing types, we show that female-specific elytra evolved at least seven times within Schizopteridae, four of those times within the Schizoptera genus-group, and that elytra reversed to macropterous wings at least twice. We propose that Schizopteridae may be an excellent model to study the selective pressures that have given rise to sexually dimorphic traits.

Zootaxa ◽  
2009 ◽  
Vol 2325 (1) ◽  
pp. 39-61 ◽  
Author(s):  
MARCELO DUARTE ◽  
ROBERT K. ROBBINS

Details of egg, larval, and pupal morphology are described and illustrated for Calycopis bellera (Hewitson) and C. janeirica (Felder), with a special emphasis on larval chaetotaxy. Wild-caught Calycopis females laid eggs on dead leaves in the laboratory, and the caterpillars successfully completed development on an artificial agar diet to which no leaves were added. Males and females of the sexually dimorphic C. bellera had been previously placed in different genera or different species groups. Calycopis janeirica had been chronically misidentified (and misspelled C. jeneirica). Males and females of this species appear to be correctly associated for the first time. Whereas C. bellera has five larval instars—as reported previously for C. caulonia—C. janeirica has four. Morphological characters of the immatures of C. bellera and C. janeirica are summarized in a table and compared with those of other reared Calycopis species.


2006 ◽  
Vol 84 (2) ◽  
pp. 225-241 ◽  
Author(s):  
M Manuel

The most recent advances concerning the phylogeny and evolution of calcareous sponges (Calcarea or Calcispongia) are reviewed here, in the light of the history of taxonomy of the group and conceptions about its evolution, starting from Haeckel's works at the end of the 19th century. Calcisponge phylogeny has recently started to be addressed using modern tools of phylogenetic reconstruction: cladistic analysis of morphological characters and molecular phylogeny (so far using 18S and 28S rDNA sequences). The monophyly of calcareous sponges is strongly supported in these works, as is their subdivision into two clades, Calcinea (whose proposed synapomorphy is the basal position of nuclei in choanocytes, with no relation to the flagella) and Calcaronea (whose possible synapomorphy is the formation of the amphiblastula larva through the original process of eversion of the stomoblastula). While the molecular phylogeny of Calcinea is still in its infancy because of insufficient taxonomic sampling, several lines are emerging for the phylogeny of Calcaronea, and these are in strong disagreement with the classification issued from the "traditional" morphological approach. Phylogenetic hypotheses also permit the reconstruction of morphological character evolution, which appears complex and subject to a high level of homoplasy.


Zootaxa ◽  
2009 ◽  
Vol 2186 (1) ◽  
pp. 1-120 ◽  
Author(s):  
JOSHUA R. JONES ◽  
LEWIS L. DEITZ

Ledrinae represent a relatively small subfamily within the very large and diverse leafhopper family Cicadellidae. Prior to this study, the subfamily contained approximately 450 species in 5 tribes and 73 genera distributed worldwide, but primarily in Australia, Africa, and the Indomalayan region. Several authors have suggested Ledrinae are not monophyletic, and recent studies based on molecular and morphological data have called the existing classification into question. The goals of this study were to collect and analyze morphological data under rigorous phylogenetic criteria in order to test the monophyly of Ledrinae, provide robust definitions for the subfamily and its tribes, and provide a phylogenetic framework for understanding relationships among these leafhoppers. New phylogenetic hypotheses are presented here regarding the monophyly of Ledrinae and its included tribes. A total of 235 morphological characters were coded for 60 species from 31 genera in the tribes Ledrini and Petalocephalini, 5 species from the tribes Stenocotini, Thymbrini, and Xerophloeini, and 10 species selected as outgroups from various other cicadellid subfamilies. Data were analyzed in PAUP*, resulting in a single completely resolved topology with many well-supported nodes. Ledrinae, as previously defined, were found to be polyphyletic with respect to Stenocotini, Thymbrini, and various ledrine genera, which were placed with the outgroup taxa. Stenocotini and Thymbrini were placed with Tartessinae, agreeing with results of other recent studies. Rubria, Hespenedra, and the Afrorubria genus group formed independent lineages within Ledrinae. The tribe Xerophloeini was placed as a basal lineage within Ledrinae closely associated with the Afrorubria group. Ledrini and Petalocephalini, as previously defined, did not form monophyletic lineages, but were randomly interspersed (paraphyletic) with respect to one another. Stenocotini and Thymbrini are here removed to the subfamily Tartessinae, and Petalocephalini is made a synonym of Ledrini. The new tribes Afrorubrini, Hespenedrini, and Rubrini are described within Ledrinae by the first author, and several new informal genus groups are named. Within Ledrini, Epiclinata Metcalf is made a synonym of Tituria Stål, Epiclinata planata (Fabricius) and Epiclinata flavomarginata Kuoh & Cai are moved to Tituria, Tituria obtusa Walker is moved to Thlasia Germar, and two additional species are included in Latycephala McKamey as new combinations. Taxa placed outside of Ledrinae in this analysis are removed to other subfamilies or considered unplaced within Cicadellidae. This newly revised classification strengthens hypotheses that the Ledrinae are a very old group within Cicadellidae. As here defined, the subfamily includes five tribes with a total of 38 genera and approximately 300 species.


2017 ◽  
Vol 31 (3) ◽  
pp. 233 ◽  
Author(s):  
Carlos E. Santibáñez-López ◽  
Ricardo Kriebel ◽  
Prashant P. Sharma

Morphology still plays a key role in the systematics and phylogenetics of most of the scorpion families and genera, including the Diplocentridae Karsch, 1880. The monophyly of this family, and the monophyly of its two subfamilies is supported by morphological characters; however, neither hypothesis has been tested using molecular data. The lack of a molecular phylogeny has prevented the study of the evolution of morphology within the family. Here, we examine the morphological evolution of several key character systems in diplocentrid systematics. We tested the monophyly of the Diplocentridae, and subsequently the validity of its two subfamilies using a five-locus phylogeny. We examined the variation and evolution of the shape of the carapace, the external surface of the pedipalp patella and the retrolateral surface of the pedipalp chelae of males and females. We also examined the phylogenetic signal of discrete and continuous characters previously reported. We show that Diplocentridae is monophyletic, but Nebinae is nested within Diplocentrinae. Therefore, Nebinae is synonymised with Diplocentrinae (new synonymy). Finally, we show that a new character system proposed here, tarsal spiniform and macrosetal counts, retains high phylogenetic signal and circumscribes independently evolving substructures within this character system.


Zootaxa ◽  
2017 ◽  
Vol 4237 (3) ◽  
pp. 583
Author(s):  
TAKUJI TACHI

Sexual dimorphism is a phenomenon in which the male and female of a species differ in features of the external morphology such as size, shape, colour, or the development of appendages. In the Diptera, stalked compound eyes, leg modifications and wing patterns are well-known examples of sexual dimorphism (McAlpine 1979; Zeil 1983; Adler & Adler 1991; Meyerrochow & Reid 1994; Wilkinson & Dodson 1996; Sivinski 1997; Baker & Wilkinson 2001; Eberhard 2002; Puniamoorthy et al. 2008). Males and females of sexually dimorphic species are often described as separate species due to the dissimilarity in external characters, thus leading to problems in identification and proper association of the sexes. In contrast to characters that are usually involved in sexual dimorphism, leg chaetotaxy is considered one of the invariable character systems, irrespective of sex, in the tribe Siphonini of the Tachinidae, and is thus widely used in keys to genera and species (O’Hara 1989; Andersen 1996). Species’ identification by DNA barcoding has been used in various groups of organisms (Hebert et al. 2003; Ratnasingham & Hebert 2013). In insects, males, usually more easily identified by morphological characters (e.g., postabdominal features) than females, are often used for barcoding. The identification of females will improve as sequence data accumulate, such as data from pairs collected in copula. In this paper, I describe sexual dimorphism in the Japanese endemic species of tachinid fly Ceromya glaucescens Tachi & Shima, 2000 of the tribe Siphonini, and use molecular and morphological data for the identification of this species. Sequence data of C. silacea (Meigen, 1824) are also included for comparison. 


2015 ◽  
Vol 36 (4) ◽  
pp. 327-338 ◽  
Author(s):  
Colin Strine ◽  
Inês Silva ◽  
Bartosz Nadolski ◽  
Matthew Crane ◽  
Curt Barnes ◽  
...  

Total body size for arboreal vipers is normally biased toward small males and larger females. We evaluated sexual dimorphism in adult and sub-adultTrimeresurus macrops, a small, arboreal green pit viper commonly found in Southeast Asia, but severely understudied. We evaluated morphological characters of 139 adultT. macropsobtained by active and opportunistic searches at Sakaerat Biosphere Reserve in northeast Thailand, from May 2012 to October 2014. We compared 7 external characters including residual index (Ri) and scaled mass index (SMI) between male and femaleT. macrops. Body length measurements and mass differed between males and females. Females had greater snout-vent length, body mass and head length and width, while males had greater tail lengths. A postocular stripe was always present on males, but never on females. Male head size was negatively correlated with SMI, which may reveal intersexual competition inT. macrops. Sexually dimorphic characters inT. macropsmay have evolved through intraspecific resource partitioning.


2020 ◽  
Vol 45 (4) ◽  
pp. 767-778
Author(s):  
Eranga Wettewa ◽  
Nick Bailey ◽  
Lisa E. Wallace

Abstract—Species complexes present considerable problems for a working taxonomy due to the presence of intraspecific variation, hybridization, polyploidy, and phenotypic plasticity. Understanding evolutionary patterns using molecular markers can allow for a more thorough assessment of evolutionary lineages than traditional morphological markers. In this study, we evaluated genetic diversity and phylogenetic patterns among taxa of the Platanthera hyperborea (Orchidaceae) complex, which includes diploid (Platanthera aquilonis) and polyploid (Platanthera hyperborea, P. huronensis, and P. convallariifolia) taxa spanning North America, Greenland, Iceland, and Asia. We found that three floral morphological characters overlap among the polyploid taxa, but the diploid species has smaller flowers. DNA sequence variation in a plastid (rpL16 intron) and a nuclear (ITS) marker indicated that at least three diploid species have contributed to the genomes of the polyploid taxa, suggesting all are of allopolyploid origin. Platanthera convallariifolia is most like P. dilatata and P. stricta, whereas P. huronensis and P. hyperborea appear to have originated from crosses of P. dilatata and P. aquilonis. Platanthera huronensis, which is found across North America, has multiple origins and reciprocal maternal parentage from the diploid species. By contrast, P. hyperborea, restricted to Greenland and Iceland, appears to have originated from a small founding population of hybrids in which P. dilatata was the maternal parent. Geographic structure was found among polyploid forms in North America. The area of Manitoba, Canada appears to be a contact zone among geographically diverse forms from eastern and western North America. Given the geographic and genetic variation found, we recommend continued recognition of four green-flowered species within this complex, but caution that there may be additional cryptic taxa within North America.


Author(s):  
A. P. Sukhorukov ◽  
M. A. Kushunina

Kochia monticola was previously considered as a synonym for the widely distributed Irano-Turanian Panderia pilosa. After the merger of Kochia and Panderia with Bassia based on molecular phylogeny, K. monticola remained a synonym of Bassia pilosa. We claim that Bassia monticola, a name proposed by Kuntze (1891) for K. monticola, should be separated from B. pilosa based on morphological characters and localised distribution in mountainous regions of Iran, Iraq, Syria, and Lebanon at altitudes 1800–2600 m a. s. l.


Genes ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 379
Author(s):  
Hou-Hong Zhang ◽  
Yu-Cheng Xie ◽  
Han-Jing Li ◽  
Ji-Chong Zhuo ◽  
Chuan-Xi Zhang

Intersex(ix), a gene involved in the sex-determining cascade of Drosophila melanogaster, works in concert with the female-specific product of doublesex (dsx) at the end of the hierarchy to implement the sex-specific differentiation of sexually dimorphic characters in female individuals. In this study, the ix homolog was identified in the brown planthopper (BPH), Nilaparvata lugens, which contained two splice variants expressed in both female and male insects. We found that Nlix played a vital role in the early nymphal development of BPH, showing an accumulated effect. RNAi-mediated knockdown of Nlix at 4th instar led to the external genital defects in both sexes, consequently resulting in the loss of reproductive ability in female and male individuals. After dsRNA injection, the males were normal on testes, while the females had defective ovarian development. Nlix was also required for early embryogenesis. Notably, when the dsNlix microinjection was performed in newly emerged females, the copulatory bursas were abnormally enlarged while the other tissues of the reproductive system developed normally. Our results demonstrated the pleiotropic roles of Nlix in embryogenesis and development of the reproductive system in a hemimetabolous insect species.


1990 ◽  
Vol 3 (1) ◽  
pp. 145
Author(s):  
DJ Colgan

This paper is a review of the use of information regarding the presence of duplicate genes and their regulation in systematics. The review concentrates on data derived from protein electrophoresis and restriction fragment length polymorphism analysis. The appearance of a duplication in a subset of a group of species implies that the members of the subset belong to the same clade. Suppression of the duplication may render this clade apparently paraphyletic, but may itself be informative of relations within the lineage through patterns of loss of expression in all, or some tissues, or through restrictions of the formation of functional heteropolymers in polymeric enzymes. Examples are given of studies which have used such information to establish phylogenetic hypotheses at the family level, to identify an auto- or allo-polyploid origin of polyploid species and to determine whether there have been single or multiple origins of such species. The likelihood of homoplasy in the patterns of appearance and regulation of duplicates depends on the molecular basis of the duplication. In particular, the contrast between the expected consequences of tandem duplication and the expression of pseudogenes emphasises the value of determining the mechanism of the original duplication. Many instances of sporadic gene duplication are now known, and polyploidisation is a common event in the evolutionary history of both plants and animals. So the opportunities to discover duplicationrelated characters will arise in many systematic studies. A program is presented to increase the chances that such useful information will be recognisable during the studies.


Sign in / Sign up

Export Citation Format

Share Document