scholarly journals Varying colour pattern, yet genetically similar: Pebble Crab Seulocia vittata (Stimpson, 1858) (Brachyura: Leucosiidae) from the southeastern coast of India

2020 ◽  
Vol 12 (5) ◽  
pp. 15612-15618
Author(s):  
Sanjeevi Prakash ◽  
Amit Kumar
Keyword(s):  
Cytochrome Oxidase ◽  
Molecular Analysis ◽  
Genetic Divergence ◽  
Sequence Divergence ◽  
Colour Pattern ◽  
Morphological Examination ◽  
Ecological Processes ◽  
Southeastern Coast ◽  
Palk Bay ◽  
Colour Patterns

Five adult specimens of leucosiid crab Seulocia vittata (Stimpson, 1858) were recently collected off the coast of Palk Bay, southern India.  Typical morphological examination revealed the presence of two colour patterns: grey and red.  Interestingly, molecular analysis based on the barcoding gene cytochrome oxidase sub unit I (COI) revealed that both grey and red colour patterns in S. vittata showed 0% sequence divergence between the specimens.  This indicates a situation of reverse cryptic behavior in this crab.  Surprisingly, the evolutionary and ecological processes leading to the absence of genetic divergence and variation in morphology (colour pattern) in S. vittata complex remain to be addressed.   

scholarly journals Dog colour patterns explained by modular promoters of ancient canid origin

2021 ◽  
Author(s):  
Danika L. Bannasch ◽  
Christopher B. Kaelin ◽  
Anna Letko ◽  
Robert Loechel ◽  
Petra Hug ◽  
...  
Keyword(s):  
Colour Pattern ◽  
Hair Cycle ◽  
Temporal And Spatial Distribution ◽  
Multiple Alleles ◽  
Haplotype Combination ◽  
Regulatory Modules ◽  
Regulatory Module ◽  
Temporal And Spatial ◽  
Selection For ◽  
Colour Patterns

AbstractDistinctive colour patterns in dogs are an integral component of canine diversity. Colour pattern differences are thought to have arisen from mutation and artificial selection during and after domestication from wolves but important gaps remain in understanding how these patterns evolved and are genetically controlled. In other mammals, variation at the ASIP gene controls both the temporal and spatial distribution of yellow and black pigments. Here, we identify independent regulatory modules for ventral and hair cycle ASIP expression, and we characterize their action and evolutionary origin. Structural variants define multiple alleles for each regulatory module and are combined in different ways to explain five distinctive dog colour patterns. Phylogenetic analysis reveals that the haplotype combination for one of these patterns is shared with Arctic white wolves and that its hair cycle-specific module probably originated from an extinct canid that diverged from grey wolves more than 2 million years ago. Natural selection for a lighter coat during the Pleistocene provided the genetic framework for widespread colour variation in dogs and wolves.

Molecular phylogeny of Clibanarius Dana, 1852 from the Indo-West Pacific: evolution of pereopod colour pattern and habitat adaptation

Crustaceana ◽  
2019 ◽  
Vol 92 (7) ◽  
pp. 799-839 ◽  
Author(s):  
Akihiro Yoshikawa ◽  
Kazuho Ikeo ◽  
Junichi Imoto ◽  
Wachirah Jaingam ◽  
Lily Surayya Eka Putri ◽  
...  
Keyword(s):  
Histone H3 ◽  
Hermit Crabs ◽  
Colour Pattern ◽  
12S Rrna ◽  
Habitat Adaptation ◽  
Soft Sediments ◽  
Mitochondrial 12S Rrna ◽  
Nuclear Histone ◽  
Colour Patterns ◽  
Hard Substrates

Abstract Species of hermit crabs in the genus Clibanarius Dana, 1852 have adapted to various environments in the intertidal areas, including hard substrates and soft sediments. These species often bear a close morphological resemblance to each other, therefore, the colouration on the pereopods can be one of the reliable characteristics to distinguish the species. However, the evolutionary relationships among species with different colour patterns and relationships between colour patterns and habitat adaptation have not previously been investigated. Therefore, we reconstructed the phylogenetic relationships among 19 species of Clibanarius based on mitochondrial [12S rRNA, 16S rRNA and cytochrome oxidase I] and nuclear [histone H3] DNA markers. The results suggest that the striped and solid colour elements have evolved multiple times independently, with the ancestral colour pattern potentially being scattered, bright colour spots with a bright colour band. Our findings also suggest that evolutionary adaptation from hard substrates to mudflats and soft sediments may have occurred at least twice.

scholarly journals Sexually dimorphic dorsal coloration in a jumping spider: testing a potential case of sex-specific mimicry

2021 ◽  
Vol 8 (6) ◽  
pp. 210308
Author(s):  
Collette Cook ◽  
Erin C. Powell ◽  
Kevin J. McGraw ◽  
Lisa A. Taylor
Keyword(s):  
Colour Pattern ◽  
Sexually Dimorphic ◽  
Sham Control ◽  
Jumping Spider ◽  
Negative Results ◽  
Potential Case ◽  
Opposite Sex ◽  
Colour Patterns ◽  
Hymenopteran Insects ◽  
Predation Rates

To avoid predation, many animals mimic behaviours and/or coloration of dangerous prey. Here we examine potential sex-specific mimicry in the jumping spider Habronattus pyrrithrix . Previous work proposed that males' conspicuous dorsal coloration paired with characteristic leg-waving (i.e. false antennation) imperfectly mimics hymenopteran insects (e.g. wasps and bees), affording protection to males during mate-searching and courtship. By contrast, less active females are cryptic and display less leg-waving. Here we test the hypothesis that sexually dimorphic dorsal colour patterns in H. pyrrithrix are most effective when paired with sex-specific behaviours. We manipulated spider dorsal coloration with makeup to model the opposite sex and exposed them to a larger salticid predator ( Phidippus californicus ). We predicted that males painted like females should suffer higher predation rates than sham-control males. Likewise, females painted like males should suffer higher predation rates than sham-control females. Contrary to expectations, spiders with male-like coloration were attacked more than those with female-like coloration, regardless of their actual sex. Moreover, males were more likely to be captured, and were captured sooner, than females (regardless of colour pattern). With these unexpected negative results, we discuss alternative functional hypotheses for H. pyrrithrix colours, as well as the evolution of defensive coloration generally.

scholarly journals Genetic divergence in mitochondrial DNA of Anopheles nuneztovari (Diptera: Culicidae) from Brazil and Colombia

2000 ◽  
Vol 23 (1) ◽  
pp. 71-78 ◽  
Author(s):  
Vera Margarete Scarpassa ◽  
Silvia Geurgas ◽  
Ana Maria L. Azeredo-Espin ◽  
Wanderli Pedro Tadei
Keyword(s):  
Mitochondrial Dna ◽  
Genetic Divergence ◽  
Nucleotide Diversity ◽  
Haplotype Diversity ◽  
Sequence Divergence ◽  
Brazilian Amazon ◽  
Restriction Endonucleases ◽  
Separate Species ◽  
Geographic Populations

In the present study, we have examined the variability in Anopheles nuneztovari mitochondrial DNA of three populations from the Brazilian Amazon and one from western Colombia (Sitronela), using four restriction endonucleases (BclI, ClaI, HindIII, SstI). The haplotype diversity (h) was slightly elevated in all populations (0.5000 to 0.6765), whereas the nucleotide diversity (pi) was lower in the Sitronela population (0.0029) and higher in populations from the Brazilian Amazon (0.0056 to 0.0098). The degree of sequence divergence (delta) estimated within the Brazilian Amazon and that in Sitronela (0.0329 to 0.0371) suggests that these geographic populations of A. nuneztovari may eventually constitute separate species. The low sequence divergence values among the three Brazilian Amazon populations (0.0012 to 0.0031) indicate that these populations are genetically similar. These results are consistent with those recently reported for allozymes of these same populations.

scholarly journals Scrapie-resistant sheep show certain coat colour characteristics

2009 ◽  
Vol 91 (1) ◽  
pp. 39-46 ◽  
Author(s):  
R. M. SAWALHA ◽  
L. BELL ◽  
S. BROTHERSTONE ◽  
I. WHITE ◽  
A. J. WILSON ◽  
...  
Keyword(s):  
Maximum Likelihood ◽  
Linear Model ◽  
Morphological Diversity ◽  
Coat Colour ◽  
Unintended Consequences ◽  
Colour Pattern ◽  
Reverse Pattern ◽  
Colour Patterns ◽  
Log Linear ◽  
The Relationship

SummarySusceptibility to scrapie is known to be associated with polymorphisms at the prion protein (PrP) gene, and this association is the basis of current selective programmes implemented to control scrapie in many countries. However, these programmes might have unintended consequences for other traits that might be associated withPrPgenotype. The objective of this study was to investigate the relationship betweenPrPgenotype and coat colour characteristics in two UK native sheep breeds valued for their distinctive coat colour patterns. Coat colour pattern, darkness and spotting andPrPgenotype records were available for 11 674 Badgerfaced Welsh Mountain and 2338 Shetland sheep. The data were analysed with a log–linear model using maximum likelihood. Results showed a strong significant association ofPrPgenotype with coat colour pattern in Badgerfaced Welsh Mountain and Shetland sheep and with the presence of white spotting in Shetland sheep. Animals with the ARR/ARR genotype (the most scrapie resistant) had higher odds of having a light dorsum and a dark abdomen than the reverse pattern. The implication of these associations is that selection to increase resistance to scrapie based only onPrPgenotype could result in change in morphological diversity and affect other associated traits such as fitness.

A new medium-sized rupicolous Cnemaspis Strauch, 1887 (Squamata: Gekkonidae) of the C. bangara clade from granite boulder habitats in Krishnagiri, Tamil Nadu, India

Zootaxa ◽  
2021 ◽  
Vol 4969 (2) ◽  
pp. 351-366
Author(s):  
ISHAN AGARWAL ◽  
TEJAS THACKERAY ◽  
AKSHAY KHANDEKAR
Keyword(s):  
New Species ◽  
Tamil Nadu ◽  
Sequence Divergence ◽  
Colour Pattern ◽  
Systematic Sampling ◽  
Anterior Portion ◽  
True Diversity ◽  
Granite Boulder ◽  
Paravertebral Region ◽  
Fourth Member

We describe a new species of the Cnemaspis bangara clade from a rocky hillock near Kugai Periya Mariamman Temple, Krishnagiri fort, Krishnagiri District of Tamil Nadu, India. Cnemaspis krishnagiriensis sp. nov. can be diagnosed from all other peninsular Indian congeners by its medium body size (maximum SVL 40 mm), heterogeneous dorsal pholidosis, spine-like tubercles absent on flanks; presence of four femoral pores on each thigh separated on either side by nine or 10 poreless scales from three continuous precloacal pores in males; tail with enlarged, strongly keeled, conical tubercles forming four whorls on anterior portion, six tubercles in first whorl, four tubercles in second to fourth whorls, enlarged tubercles restricted to only paravertebral region on rest of the tail; median row of sub-caudals smooth and distinctly enlarged, and a unique colour pattern. The new species can be diagnosed from members of C. bangara clade by the number of dorsal tubercles rows at mid-body, the number of enlarged tubercles in paravertebral rows, the number of ventral scales across belly at mid-body, the number longitudinal ventral scales from mental to cloaca, the number of femoral and precloacal pores and poreless scales separating these series, and subtle colour pattern differences; besides 9.2–17.6 % uncorrected ND2 sequence divergence. Cnemaspis krishnagiriensis sp. nov. is the fourth member of the recently described bangara clade and is the first that is known to be distributed <900 m asl.. The discovery of yet another endemic species of Cnemaspis from lower elevations of the Mysore Plateau once again highlights the need of dedicated systematic sampling to uncover the true diversity of Cnemaspis. We also address a nomenclatural issue related to the recently described Cnemaspis stellapulvis Khandekar, Thackeray & Agarwal. 

Cautery-induced colour patterns in Precis coenia (Lepidoptera: Nymphalidae)

Development ◽  
1985 ◽  
Vol 86 (1) ◽  
pp. 191-203
Author(s):  
H. F. Nijhout
Keyword(s):  
Computer Simulations ◽  
Hind Wing ◽  
Wing Surface ◽  
Colour Pattern ◽  
Physiological Conditions ◽  
Classical Work ◽  
Pattern Determination ◽  
Colour Patterns ◽  
Experimental Findings ◽  
Precis Coenia

Cautery of the dorsal hind wing in the butterfly, Precis coenia, induces the formation of a concentric colour pattern around the site of injury. The induced pattern is identical in pigmentation to the eyespots that normally develop on this wing surface. This response to cautery also occurs, though much less dramatically, on the ventral forewing. In addition to the peculiar response to cautery, the dorsal hindwing of Precis also develops a series of unique pattern aberrations in response to coldshock. These consist of irregular elongation of the anterior eyespot along the proximodistal axis of the wing. In the most dramatic aberrations the eyespot field covers the entire anterior half of the wing surface. An analysis is presented that attempts to reconcile the effects of cautery on the Precis hindwing with the very different morphological effects of cautery on the colour pattern of Ephestia kühniella, described by Kühn & Von Engelhardt. Computer simulations reveal that the finding presented in this paper, as well as the classical work on Ephestia, can both be explained by assuming that the site of cautery becomes a sink for one of the morphogens involved in colour pattern determination. The experimental findings furthermore indicate that minor perturbations of the wing epidermis can evoke the physiological conditions that attend normal eyespot determination. It is shown that this interpretation also helps to explain the unusual pattern modifications following coldshock.

The immature stages of the genus Trepobates Uhler (Hemiptera: Heteroptera: Gerridae), with an identification key to instars and the description of the nymphs of T. taylori (Kirkaldy)

Zootaxa ◽  
2011 ◽  
Vol 2733 (1) ◽  
pp. 1 ◽  
Author(s):  
SUSANA AMANDA KONOPKO ◽  
SILVIA ANA MAZZUCCONI
Keyword(s):  
Antennal Segment ◽  
Identification Key ◽  
Colour Pattern ◽  
Immature Stages ◽  
Viii And Ix ◽  
Colour Patterns ◽  
First Time

The egg and five instars of Trepobates are described based on examined material of T. taylori and published information of T. inermis, T. knighti, T. panamensis, T. pictus, T. subnitidus and T. trepidus. The characters most useful in identifying nymphs I– V of Trepobates are: the width of the head; the lengths of the antennae, femora 1–3, tibiae 2–3 and tarsus 2–3; the Y-shaped ecdysial line of the head; the colour patterns of the proand mesonotum; and the urosternites VIII and IX. A key to the five nymphal instars of Trepobates is provided. The five instars of T. taylori are described and illustrated for the first time, with emphasis on the morphometry and colour pattern of selected structures, and chaetotaxy of the antennae; the egg is figured and redescribed. The characters useful in identifying nymphs I–V of this species are: the colour pattern of the head; the chaetotaxy of the antennal segment I; the lengths of the antennal segment III and mesonotum; and the width of the pronotum. Differences between sexes in nymphs IV and V are presented.

scholarly journals Phenotypic variation in Heliconius erato crosses shows that iridescent structural colour is sex-linked and controlled by multiple genes

2018 ◽  
Vol 9 (1) ◽  
pp. 20180047 ◽  
Author(s):  
Melanie N. Brien ◽  
Juan Enciso-Romero ◽  
Andrew J. Parnell ◽  
Patricio A. Salazar ◽  
Carlos Morochz ◽  
...  
Keyword(s):  
Phenotypic Variation ◽  
Genetic Basis ◽  
Sex Chromosome ◽  
Scattering Data ◽  
Colour Pattern ◽  
Structural Colour ◽  
X Ray Scattering ◽  
Multiple Genes ◽  
Colour Patterns ◽  
Blue Reflectance

Bright, highly reflective iridescent colours can be seen across nature and are produced by the scattering of light from nanostructures. Heliconius butterflies have been widely studied for their diversity and mimicry of wing colour patterns. Despite iridescence evolving multiple times in this genus, little is known about the genetic basis of the colour and the development of the structures which produce it. Heliconius erato can be found across Central and South America, but only races found in western Ecuador and Colombia have developed blue iridescent colour. Here, we use crosses between iridescent and non-iridescent races of H. erato to study phenotypic variation in the resulting F 2 generation. Using measurements of blue colour from photographs, we find that iridescent structural colour is a quantitative trait controlled by multiple genes, with strong evidence for loci on the Z sex chromosome. Iridescence is not linked to the Mendelian colour pattern locus that also segregates in these crosses (controlled by the gene cortex ). Small-angle X-ray scattering data show that spacing between longitudinal ridges on the scales, which affects the intensity of the blue reflectance, also varies quantitatively in F 2 crosses.

Multi-instar descriptions of cave dwelling Erythraeidae (Trombidiformes: Parasitengona) employing an integrative approach

Zootaxa ◽  
2019 ◽  
Vol 4717 (1) ◽  
pp. 137-184 ◽  
Author(s):  
SAMUEL GEREMIAS DOS SANTOS COSTA ◽  
HANS KLOMPEN ◽  
LEOPOLDO FERREIRA DE OLIVEIRA BERNARDI ◽  
LUCIANA CARDOSO GONÇALVES ◽  
DANTE BATISTA RIBEIRO ◽  
...  
Keyword(s):  
Life Cycle ◽  
Cytochrome Oxidase ◽  
Molecular Analysis ◽  
Species Delimitation ◽  
Morphological Changes ◽  
Molecular Data ◽  
Coi Gene ◽  
Integrative Approach ◽  
Larval Instars ◽  
Individual Host

The life cycle of Parasitengona includes major morphological changes precluding an instar association based only on the morphology. This makes rearing and/or molecular data necessary to associate the heteromorphic instars. Most of the described species are known from either post larval instars or larva. Following a previous study on Palearctic Erythraeidae, in the present study the instar association was made through an integrative approach including rearing trials and molecular analysis of the cytochrome oxidase I (COI) gene with the Bayesian Generalized Mixed Yule Coalescent (bGMYC) algorithm for species delimitation. Two new cave dwelling Erythraeidae (Trombidiformes: Parasitengona) species are described Lasioerythraeus jessicae sp. nov. and Leptus sidorchukae sp. nov. including all active instars. Additionally, a complete description of the previously unknown adults of Charletonia rocciai Treat & Flechtmann, 1979 is provided with notes on the larva and deutonymph. We also demonstrate experimentally that Ch. rocciai larvae are not attached to the same individual host during the entire feeding stage. We discuss the presence of troglomorphisms in Le. sidorchukae sp. nov.; and the distribution of the species. 

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