scholarly journals A ZZ/ZW sex chromosome system in a new species of the genus Parodon (Pisces, Parodontidae)

Caryologia ◽  
2002 ◽  
Vol 55 (2) ◽  
pp. 139-150 ◽  
Author(s):  
Liano Centofante ◽  
Luiz Antonio Carlos Bertollo ◽  
Orlando Moreira-Filho
2021 ◽  
Vol 15 (4) ◽  
pp. 467-505
Author(s):  
Dmitry A. Gapon ◽  
Valentina G. Kuznetsova ◽  
Anna Maryańska-Nadachowska

A new species, Rhaphidosoma paganicumsp. nov. (Heteroptera: Reduviidae: Harpactorinae: Rhaphidosomatini), is described from the Dry Zone of Myanmar. It is the fifth species of Rhaphidosoma Amyot et Serville, 1843, known from the Oriental Region, and the first record of the genus for Myanmar and Indochina. The structure of the external and internal terminalia of the male and female is described and illustrated in detail. The completely inflated endosoma is described for the first time in reduviids. The complex structure of the ductus seminis is shown; it terminates with a voluminous seminal chamber which opens with a wide secondary gonopore and may be a place where spermatophores are formed. The new species is compared with all congeners from the Oriental Region and Western Asia. It is characterised by the absence of distinct tubercles on the abdominal tergites of the male, the presence only two long tubercles and small rounded ones on the abdominal tergites VII and VI, respectively, in the female, the presence of short fore wing vestiges which are completely hidden under longer fore wing vestiges, and other characters. In addition to the morphological description, an account is given of the male karyotype and the structure of testes of Rh. paganicumsp. nov. and another species of Harpactorinae, Polididus armatissimus Stål, 1859 (tribe Harpactorini). It was found that Rh. paganicumsp. nov. has a karyotype comprising 12 pairs of autosomes and a multiple sex chromosome system (2n♂=24A+X1X2X3Y), whereas P. armatissimus has a karyotype comprising five pairs of autosomes and a simple sex chromosome system (2n♂=10A+XY). The males of these species were found to have seven and nine follicles per testis, respectively. FISH mapping of 18S ribosomal DNA (major rDNA) revealed hybridisation signals on two of the four sex chromosomes (Y and one of the Xs) in Rh. paganicumsp. nov. and on the largest pair of autosomes in P. armatissimus. The presence of the canonical “insect” (TTAGG)n telomeric repeat was detected in the chromosomes of both species. This is the first application of FISH in the tribe Raphidosomatini and in the genus Polididus Stål, 1858.


Zootaxa ◽  
2017 ◽  
Vol 4303 (1) ◽  
pp. 140
Author(s):  
LUCAS HENRIQUE BONFIM SOUZA ◽  
ANTONIO DOMINGOS BRESCOVIT ◽  
DOUGLAS ARAUJO

Studies on spider chromosomes are very scarce, with 44 spider families without any cytogenetically analyzed species. Nevertheless, chromosomal characteristics can be useful for species delimitation, such as the sex chromosome system (SCS), which is particularly diverse in spiders. In this study, we describe Synotaxus jaraguari n. sp., based on male and female specimens from midwestern Brazil. This species has a distinctive “horn” in the male ocular area and seems related to a group of species that includes Synotaxus monocerus (Caporiacco, 1947), S. itabaiana Santos & Rheims, 2005 and S. siolli Santos & Rheims, 2005. We also present the first karyotype study on Synotaxidae. The mitotic and meiotic cells of S. jaraguari n. sp. revealed 2n♂ = 22 + XY and 2n♀ = 22 + XX telocentric chromosomes. This is the ninth spider species with a XY/XX SCS, which is extremely rare in the group. 


Zootaxa ◽  
2008 ◽  
Vol 1693 (1) ◽  
pp. 27 ◽  
Author(s):  
JUAN A. ZARAGOZA ◽  
FRANTI“EK ŠÿÁHLAVSKÝ

Roncus montsenyensis sp. nov. is described from Montseny Natural Park (Catalonia, Spain). The new species is geographically and morphologically close to Roncus cadinensis Zaragoza, 2007, but can be separated from it by palpal morphometrics, the chelal microsetae pattern and karyology. The diploid number was found to be 2n=16 in R. montsenyensis, with only biarmed chromosomes. The diploid number was found to be 2n=38 in R. cadinensis, with a predominance of acrocentric chromosomes. Both species possess the XY sex chromosome system and the X and Y chromosomes are only weakly differentiated.


ZooKeys ◽  
2020 ◽  
Vol 1007 ◽  
pp. 85-128
Author(s):  
David R. Maddison

Two new species of Bembidion are described from river shores in North America. One, Bembidion mimbressp. nov., from the Gila River watershed in the lands of the Mimbres culture in New Mexico and Arizona, is closely related to the widespread Bembidion levigatum. DNA sequences from several linkage groups and morphology provide evidence of the distinctiveness of B. mimbres. The second, Bembidion corgenomasp. nov., has been the subject of recent genomic and transcriptomic studies. It belongs in the Bembidion transversale subgroup, and occurs from California north to British Columbia, east to Montana and Nevada. The B. transversale subgroup as a whole is reviewed, and morphological characters that distinguish B. corgenoma from the similar and sympatric B. transversale and B. erosum are described and illustrated. DNA sequences of these three species show no consistent differences in 28S, COI, CAD, and Topoisomerase, and a coalescent species delimitation analysis reveals no notable structure within the complex. This is the first known trio of species within Bembidion for which those genes provide no clear signal of species boundaries. A neotype is designated for the one name in the group that lacks a primary type, Bembidium haplogonum Chaudoir. Chromosomes of the new species and their relatives are as is typical for Bembidion, with eleven pairs of autosomes and an XY/XX sex chromosome system.


2018 ◽  
Vol 49 (3) ◽  
pp. 241-298 ◽  
Author(s):  
Claudia Hemp ◽  
Klaus-Gerhard Heller ◽  
Elżbieta Warchałowska-Śliwa ◽  
Beata Grzywacz ◽  
Andreas Hemp

Two new genera of East African Acrometopini are erected: the monotypicPeronurellan. gen. withP. centralisn. sp. from Miombo woodlands in central Tanzania, andTenerasphagan. gen. for a morphological uniform group of species formerly included inHoratosphaga,T. chyuluensisn. sp.,T. mbulun. sp.T. nanyuki,T. nudan. comb,T. meruensisn. comb,T. teneran. comb andT. bazeletaen. comb. Additional species are described in the generaAltihoratosphaga,LamecosomaandPeronura. Keys to African genera of Acrometopini and species of the genusTenerasphagaare provided. We review the male calling songs and the morphology of the acoustical apparatus and discuss how the morphology of the stridulatory files explains the complicated song patterns and elements. All Acrometopini species showed a plesiomorphic karyotype with a diploid chromosome number of 2n = 31 and a X0 sex chromosome system in males.


1983 ◽  
Vol 94 (9-10) ◽  
pp. 591-593
Author(s):  
Kostas Papanicolaou ◽  
Stella Kokkini
Keyword(s):  

1983 ◽  
Vol 94 (3-4) ◽  
pp. 165-172
Author(s):  
T. R. Dudley
Keyword(s):  

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