scholarly journals An overview of the sexual dimorphism in Echiniscus (Heterotardigrada, Echiniscoidea), with the description of Echiniscus masculinus sp. nov. (the virginicus complex) from Borneo

2020 ◽  
Vol 96 (1) ◽  
pp. 103-113
Author(s):  
Piotr Gąsiorek ◽  
Katarzyna Vončina ◽  
Łukasz Michalczyk
Keyword(s):  
New Species ◽  
Sexual Dimorphism ◽  
Southeast Asia ◽  
Current Knowledge ◽  
The Body ◽  
Genetic Evidence ◽  
Body Proportions ◽  
Dioecious Species

Members of the genus Echiniscus C.A.S. Schultze, 1840 are mostly unisexual, with thelytokously reproducing females. Therefore, every newly described dioecious species in the genus is particularly interesting. Here, we describe Echiniscus masculinussp. nov. from Gunung Kinabalu, the highest peak of Borneo and the entire Southeast Asia. The new species belongs in the predominantly parthenogenetic E. virginicus complex, and its females are confusingly similar to females of the pantropical E. lineatus Pilato et al., 2008, another member of this group. However, genetic evidence and noticeable sexual dimorphism clearly delineate the new species. Males of E. masculinussp. nov. are unlike females in the body proportions, cuticular sculpturing, and appendage configuration. The new discoveries provide a justification to review the current knowledge about evolution and forms of sexual dimorphism within Echiniscus.

scholarly journals SEXUAL DIMORPHISM IN PSEUDOPUS APODUS (REPTILIA: SAURIA: ANGUIDAE) FROM THE STEPPE CRIMEA

2018 ◽  
Vol 19 ◽  
pp. 1-21
Author(s):  
Oleg V. Kukushkin ◽  
Igor V. Dovgal
Keyword(s):  
Sexual Dimorphism ◽  
Morphometric Parameters ◽  
The Body ◽  
Body Proportions ◽  
Reliable Determination ◽  
Kerch Peninsula ◽  
The Crimea ◽  
Males And Females ◽  
Almost All

The current paper is focused on sexual dimorphism of a giant glass lizard, or sheltopusik, Pseudopus apodus apodus (Pallas, 1775) from its northernmost populations inhabiting the Crimea. In total, 72 P. apodus individuals (45 males and 27 females) were collected at the Kerch Peninsula during 2013–2017. To estimate the variability, 13 morphometric parameters and 18 indices characterizing the head and body proportions were used. It was found that males and females differed significantly by means of almost all parameters, except the body and tail sizes. Besides that, the differences by 10 ratios characterizing head proportions were revealed as well. However, a reliable determination of the lizard sex using linear sizes and/or ratios values seems to be impossible because of the strong overlap of the variability ranges in both sexes. At the same time, the use of the canonical discriminant analysis by the complex of morphometric parameters and by ratios has shown that the males and females in both datasets are classified correctly basing on the sex with an accuracy approximating 100%. The differences in the allometric growth of males and females partially define the sexual dimorphism of P. apodus on head size and shape. A sex-related differences in the development of at least one pair of parameters (head and snout lengths) were clearly evident, since isometry was established for males, while allometry ‒ for females. Moreover, the systems of correlation between the body and head parts differ in both sexes. Thus, male characterisitics correlate significanly, while the female ones were less toughly connected, and some pairs of parameters did not correlate at all.

A taxonomic revision of Asthenodipsas malaccana Peters, 1864 (Squamata: Pareidae) with a description of a new species from Borneo

Zootaxa ◽  
2020 ◽  
Vol 4729 (1) ◽  
pp. 1-24
Author(s):  
EVAN S.H. QUAH ◽  
L. LEE GRISMER ◽  
KELVIN K.P. LIM ◽  
M.S. SHAHRUL ANUAR ◽  
KIN ONN CHAN
Keyword(s):  
New Species ◽  
Southeast Asia ◽  
Taxonomic Status ◽  
Taxonomic Revision ◽  
The Body ◽  
Malay Peninsula ◽  
Snake Species ◽  
Black Patch ◽  
True Diversity ◽  
A New Species

A reappraisal of the taxonomic status of the Dark-necked Slug Snake (Asthenodipsas malaccana Peters, 1864) across its range revealed that populations from Borneo are not conspecific with true A. malaccana from the Thai-Malay Peninsula and Sumatra, and is therefore described herein as new. Asthenodipsas borneensis sp. nov. can be distinguished from A. malaccana and other congeners by the absence of a preocular and suboculars, seven or eight supralabials with 3rd and 4th in contact with orbit, 4–7 infralabials with 2nd or 3rd pair in contact, two pairs of posterior inframaxillaries, 15/15/15 rows of dorsal scales, presence of sharp vertebral keel, divided subcaudals, maximum recorded SVL=441 mm, 166–179 ventrals, 35–48 subcaudals, head white to greyish brown and dorsum beige to orange-brown with a conspicuous dark-brown or black patch on the neck followed by multiple, narrow, vertical, dark bands along the rest of the body and tail. This discovery adds to a growing number of new slug snake species recently described from Southeast Asia and highlights the underestimated diversity in this family, especially in Borneo. Taxonomic revisions of the reptiles and amphibians of Borneo are still needed before the true diversity of the island and the relationships of the various taxa can be fully understood. 

Four new species and an identification key for Stygodesmodora Blome, 1982 (Nematoda: Spiriniinae) from the continental shelf off northeastern Brazil 

Zootaxa ◽  
2017 ◽  
Vol 4294 (1) ◽  
pp. 46
Author(s):  
ALEXANDRE L. LARRAZÁBAL-FILHO ◽  
PATRÍCIA F. NERES ◽  
ANDRÉ M. ESTEVES
Keyword(s):  
New Species ◽  
Sexual Dimorphism ◽  
Continental Shelf ◽  
The Body ◽  
Identification Key ◽  
Northeastern Brazil ◽  
Marine Nematodes ◽  
Undescribed Species ◽  
Potiguar Basin

Four previously undescribed species of marine nematodes were collected on the continental shelf of the Potiguar Basin in northeastern Brazil. Stygodesmodora amphidialis sp. n. has a large fovea amphidialis, long cephalic setae, globular spermatic cells, 6–8 tubular supplements and button-like caudal papillae. Stygodesmodora paramphidialis sp. n. is similar but can be differentiated by the presence of a bipartite lumen and a fovea amphidialis smaller than in S. amphidialis sp. n. Stygodesmodora robusta sp. n. has a relatively robust body, strongly annulated cuticle, one large dorsal tooth and a small ventral tooth, one row of nine ventrally placed precloacal setae, and arched spicules. Stygodesmodora potiguensis sp. n. has the cuticle strongly annulated, many setae along the body, supplements absent, and sexual dimorphism in the size of the fovea amphidialis. These four new species increase to seven the number of taxa known in the genus. 

Five new species of Parapercis (Perciformes: Pinguipedidae) from southeast Asia and northwest Australia

Zootaxa ◽  
2017 ◽  
Vol 4320 (1) ◽  
pp. 121
Author(s):  
JEFFREY W. JOHNSON ◽  
HIROYUKI MOTOMURA
Keyword(s):  
New Species ◽  
Southeast Asia ◽  
Western Australia ◽  
The Philippines ◽  
The Body ◽  
Andaman Sea ◽  
Single Specimen ◽  
Pectoral Fin ◽  
Caudal Fin ◽  
Northwest Australia

Five new species of sandperch (Pinguipedidae: Parapercis) from southeast Asia and northwest Australia are described. Parapercis soliorta sp. nov., known from a single specimen acquired from the Iloilo Central Market, taken off Iloilo, Panay Island, Philippines, is readily distinguished by a unique colour pattern including a series of nine brilliant yellow-ringed red spots along the body and caudal fin. Parapercis rubricaudalis sp. nov. is described from 15 specimens trawled between Dampier and Cape Leveque, Western Australia in 70–119 m and a single specimen taken by aquarium fish collectors off Zambales, Luzon, Philippines. It has the posterior end of the opercular ridge armed with two or three strong spines, the margin of the preopercle, subopercle and interopercle strongly serrated, and colouration including six broad irregular orange to reddish bands across the body, and the pelvic fins and lower third of the caudal fin crimson-red. A complex of three closely related species, Parapercis flavipinna sp. nov. from the Philippines, Parapercis caudopellucida sp. nov. from Myanmar and Parapercis hoi sp. nov. from northwest Australia and the Philippines, share a series of six or seven irregular dusky double blotches along the sides, a series of small black spots along the base of the soft dorsal-fin, a pair of dusky blotches on the caudal-fin base, and mostly similar meristic values. Parapercis hoi sp. nov. is known from four specimens trawled off Broome, Western Australia, in 97–109 m and one specimen trawled in the Sibuyan Sea, Philippines, in 73–84 m. It may be distinguished from its two closest congeners by cycloid cheek scales, a distinctive anal-fin colouration, and lower pectoral-fin ray, gill raker and lateral-line scale counts. Parapercis caudopellucida sp. nov., trawled in 125–129 m in the Andaman Sea off southern Myanmar, is described from two specimens. It differs from its two closest congeners most obviously by cycloid cheek scales, caudal-fin colouration, and the presence of a dusky bar extending posteroventrally from the tip of the maxilla to the anteroventral edge of the preopercle. Parapercis flavipinna sp. nov. is described from two specimens acquired from the Iloilo Central Market, taken off Iloilo, Panay Island, in the Philippines. It is distinguished most readily by the presence of ctenoid cheek scales and colouration including rows of bright yellow spots on the anal and caudal fins, a yellow upper lip, a series of yellow streaks and spots on the head, and fleshy pectoral-fin base with a large dark purplish grey blotch followed by a distinct white-edged black bar. 

Three new species of the genus Nemophora Hoffmannsegg (Lepidoptera, Adelidae) from Southeast Asia

Zootaxa ◽  
2020 ◽  
Vol 4767 (3) ◽  
pp. 477-484
Author(s):  
MIKHAIL V. KOZLOV
Keyword(s):  
New Species ◽  
Southeast Asia ◽  
The Body ◽  
The Other ◽  
Three New Species ◽  
White Colour

Three new, beautifully patterned species of the genus Nemophora Hoffmannsegg are described from Myanmar (N. alba sp. nov.), Indonesia (N. decoratella sp. nov.) and Borneo (N. bruneiella sp. nov.). Nemophora alba differs from all known Nemophora species by white colour of the body, including head, thorax, abdomen, legs, and larger part of wings. Nemophora bruneiella and N. decoratella share two possible synapomorphies, which distinguish them from other Nemophora species: forewing with four to five compact small dark brown spots along dorsum, and basal field of forewing with silver-white triangular spot adjacent to internal border of fascia. The taxonomic affinities of the described species with the other members of the genus Nemophora remain unknown. 

New loricariid fishes from headwaters on Serra da Mantiqueira and Complexo do Espinhaço, Minas Gerais State, Brazil (Teleostei: Siluriformes: Loricariidae)

Zootaxa ◽  
2019 ◽  
Vol 4586 (3) ◽  
pp. 401 ◽  
Author(s):  
JOSÉ C. DE OLIVEIRA ◽  
OSVALDO T. OYAKAWA
Keyword(s):  
New Species ◽  
Sexual Dimorphism ◽  
Rio Grande ◽  
First Record ◽  
Minas Gerais ◽  
The Body ◽  
Minas Gerais State ◽  
Adipose Fin ◽  
Three New Species ◽  
Cadeia Do Espinhaço

Three new species, of three different genera of loricariids, are described from the headwaters of Serra da Mantiqueira and Cadeia do Espinhaço, in Southeastern Minas Gerais State, Brazil. In this region, the Serra da Mantiqueira and the Complexo do Espinhaço are the highest points of the Brazilian Shield and delimits the headwaters of four drainages: São Francisco, Paraná, Doce and Paraíba do Sul basins. Harttia intermontana, n. sp., is described from the headwaters of the Rio Doce basin and is the first record of the genus in this basin. The new species can be distinguished from its congeners by the pattern of abdominal covering, presence of preanal plates, presence and pattern of ornamentation of canal plate, and some characteristics related to sexual dimorphism. Pareiorhaphis togoroi, n. sp., is described from the headwaters of the Rio das Mortes basin, tributary to the Rio Grande, in the upper Rio Paraná drainage, and represents the first record of the genus to this drainage, thus expanding its geographic distribution. It can be distinguished from most congeners by the absence of preadipose azygous plates, and characteristics related to secondary sexual characters of mature males: presence of odontodes on the lateral margin of head plus the absence of long hypertrophied odontodes on pectoral-fin spine. Neoplecostomus pirangaensis, n. sp., is described from the headwaters of the Rio Piranga, Rio Doce basin. The new species differs from all congeners by the much-reduced dermal platelets on the abdomen, devoid of developed odontodes between the insertions of the pectoral and pelvic fins. Neoplecostomus pirangaensis can also be distinguished from all congeners, except N. botucatu and N. paranensis, due to the complete absence of vestiges of the adipose fin (vs. vestiges, or adipose fin moderate to well developed and always present). The new species differs from N. botucatu by the absence of conspicuous dark spots all over the body and the presence of common dorsal bands in juveniles, and almost totally black in adults. It differs from N. paranensis by the bigger and less numerous teeth. Additionally, the new species differs from Neoplecostomus doceensis by the absence of enlarged fleshy folds between dentaries, and absence of a lateronasal plate. 

The Hemerodromiinae (Diptera: Empididae) of New Zealand  II. Chelipoda Macquart

Zootaxa ◽  
2007 ◽  
Vol 1537 (1) ◽  
pp. 1-88 ◽  
Author(s):  
ADRIAN R. PLANT
Keyword(s):  
New Species ◽  
New Zealand ◽  
Sexual Dimorphism ◽  
Structure Function ◽  
Current Knowledge ◽  
Cladistic Analysis ◽  
The Other ◽  
Male Characters ◽  
High Incidence ◽  
Male Genital

The genus Chelipoda Macquart in New Zealand is revised; full descriptions and keys are provided for all 38 species and 22 new species are recognized: C. aritarita sp. n., C. atrocitas sp. n., C. australpina sp. n., C. brevipennis sp. n., C. cornigera sp. n., C. cycloseta sp. n., C. didhami sp. n., C. dominatrix sp. n., C. ferocitrix sp. n., C. fuscoptera sp. n., C. gracilis sp. n., C. lateralis sp. n., C. macrostigma sp. n., C. mediolinea sp. n., C. monorhabdos sp. n., C. puhihiroa sp. n., C. rakiuraensis sp. n., C. rangopango sp. n., C. tainuia sp. n., C. tangerina sp. n., C. ultraferox sp. n. and C. venatrix sp n. Lectotypes are designated for C. oblinita Collin and C. oblata Collin. Lectotypes and paralectotypes are designated for C. abdita Collin, C. abjecta Collin, C. consignata Collin, C. delecta Collin, C. inconspicua Collin, C. interposita Collin, C. longicornis Collin, C. moderata Collin, C. modica Collin, C. recurva Collin, C. secreta Collin and C. trepida Collin. C. recurva Collin syn. n. is designated a junior synonym of C. mirabilis Collin. A high incidence of profound sexual dimorphism is reported and structure-function relationships of exaggerated male characters are explored. Cladistic analysis resolved two clades characterised by degree of thoracic elongation, male genital flexion, fusion of cerci with epandrial lobes and shape of cell cup. It is hypothesized that one lineage gave rise to Palaearctic and Nearctic forms while the other lineage has a ‘Gondwanan’ distribution. Loss of crossvein dm-cu in Phyllodromia Zetterstedt is interpreted as a homoplasy which has occurred in both lineages of Chelipoda and of no generic significance. Relationships with other Chelipoda-like genera Ptilophyllodromia Bezzi and Monodromia Collin are discussed and current knowledge of diversity, distribution, ecology and behaviour is summarised.

Revision of the Australian Eviphididae (Acari: Mesostigmata)

Zootaxa ◽  
2010 ◽  
Vol 2596 (1) ◽  
pp. 1
Author(s):  
R. B. HALLIDAY
Keyword(s):  
New Species ◽  
Sexual Dimorphism ◽  
The Body ◽  
Dorsal Shield ◽  
Typical Member ◽  
The Third ◽  
Unidentified Species ◽  
Males And Females ◽  
Rich Fauna ◽  
Mite Family

The Australian fauna of the mite family Eviphididae (Acari: Mesostigmata) is revised. A total of 14 species is recorded, 10 of which are described as new: Alliphis halleri (G. & R. Canestrini), A. transversus sp. nov., Evimirus pentagonius Karg, E. scutellatus sp. nov., E. uropodinus (Berlese), Scarabaspis masani sp. nov., S. orientalis (Berlese), S. sternalis sp. nov., S. victoriensis sp. nov., Thinoseius helenae sp. nov., T. jarretti sp. nov., T. papillatus sp. nov., T. peltatus sp. nov., and T. variabilis sp. nov.. These species occur in soil, leaf litter, dung, compost, and seaweed, where they appear to prey on nematodes. A key for identification of these genera and species is provided. Several of the new species have character states that are unusual for their genera. In Alliphis transversus, the first pair of sternal lyrifissures are large, and oriented transversely to the long axis of the body, instead of obliquely, as is normal for the genus. Scarabaspis sternalis is unusual in having the third pair of sternal pores on the sternal shield. It also shows extensive geographic variation in the amount of ornamentation of the dorsal shield. Scarabaspis victoriensis has only one of the setae on coxa I modified into a flat oval-shaped disc instead of both, as is usual for the genus. Scarabaspis masani has normal setiform setae on both coxae I and II, but otherwise appears to be a typical member of the genus. The five species of Thinoseius described here show strong sexual dimorphism, which makes it impossible to associate the males and females of some species. Deutonymphs of an unidentified species of Thinoseius sp. are recorded as phoretic on flies of the genus Thoracochaeta (Sphaeroceridae). The eviphidid fauna of Australia is much smaller than that of Europe. This appears to be the result of the absence of small or monotypic genera, and the fact that Australian native mammals do not produce large quantities of wet dung suitable for the development of a rich fauna of coprophilous mites and dung beetles.

Proctocaecum blairi sp. nov. (Digenea, Cryptogonimidae) from the freshwater crocodile, Crocodylus johnstoni, in Northern Territory, Australia

2010 ◽  
Vol 55 (3) ◽  
Author(s):  
Vasyl Tkach ◽  
Scott Snyder
Keyword(s):  
New Species ◽  
Relative Length ◽  
Anterior Testis ◽  
Northern Territory ◽  
The Body ◽  
Body Proportions ◽  
Diagnostic Features ◽  
Crocodylus Johnstoni ◽  
Freshwater Crocodile ◽  
Australian Freshwater

AbstractProctocaecum blairi sp. nov. is described from specimens found in the intestine of an Australian freshwater crocodile, Crocodylus johnstoni, from Northern Territory, Australia. The most important diagnostic features of the new species are the body proportions and size, the position of the pharynx (relative length of the prepharynx and oesophagus), the relative length and position of the vitelline fields, and the number, shape and size of the circumoral spines. The new species is morphologically most similar to Proctocaecum atae, P. elongatum, P. crocodili, P. gairhei and Acanthostomum slusarskii. It differs from all of these species in having a much longer prepharynx, and differs from both P. atae and P. crocodili in having a much longer body and posteriorly situated vitelline fields. Proctocaecum blairi sp. nov. differs from P. elongatum in having a shorter body, a greater forebody to hindbody ratio, a much smaller ventral sucker, and a higher number of circumoral spines (23 vs 21 in P. elongatum). The new species differs from P. gairhei in possessing a much larger body length:width ratio and an ovary separated from the anterior testis by a seminal receptacle. Acanthostomum slusarskii lacks a gonotyl and has fewer circumoral spines than the new species. Proctocaecum blairi sp. nov. is the third species of Proctocaecum and the fourth cryptogonimid species known from crocodiles in Australia.

scholarly journals Sexual dimorphism in the electric knifefish, Gymnorhamphichthys rondoni (Rhamphichthyidae: Gymnotiformes)

2019 ◽  
Vol 49 (3) ◽  
pp. 213-220
Author(s):  
Elisa Queiroz GARCIA ◽  
Jansen ZUANON
Keyword(s):  
Sexual Dimorphism ◽  
Body Height ◽  
Principal Component ◽  
The Body ◽  
Vertical Line ◽  
Head Length ◽  
Genital Papilla ◽  
Adult Males ◽  
Dioecious Species ◽  
Males And Females

ABSTRACT Sexual dimorfism refers to morphological differences between males and females of a species. It may be a result of different selection pressures acting on either or both sexes and may occur in any sexually-reproducing dioecious species, including fishes. We analyzed 63 females and 63 adult males of Gymnorhamphichthys rondoni (Gymnotiformes) collected by us or deposited in museum collections. Sex was identified through abdominal dissection. We measured length from snout to posterior end of anal-fin, anal-fin length, distance from anus to anal-fin origin, distance from genital papilla to anal-fin origin, body width at beginning of anal-fin, and head length. Morphometric data submitted to a Principal Component Analysis (PCA) grouped males and females according to variables related to body size (along the first component) and to head length and body height along the second and third components. Females were larger than males, whereas males had proportionally larger heads and higher bodies than females. The urogenital papilla of males and females showed differences in shape, size and relative position on the body. The female papilla was elongated horizontally, larger than that of males, and was located on a vertical line below the eye, while the papilla of the males was vertically elongated and located on a vertical line below the operculum. To our knowledge, this is the first recorded case of sexual dimorphism in a species of Rhamphichthyidae, a condition that is now known in all the currently recognized families of Gymnotiformes.

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