Concerted variation in melanogenesis genes underlies emergent patterning of plumage in capuchino seedeaters

Coloration traits are central to animal communication; they often govern mate choice, promote reproductive isolation and catalyse speciation. Specific genetic changes can cause variation in coloration, yet far less is known about how overall coloration patterns—which involve combinations of multiple colour patches across the body—can arise and are genomically controlled. We performed genome-wide association analyses to link genomic changes to variation in melanin (eumelanin and pheomelanin) concentration in feathers from different body parts in the capuchino seedeaters, an avian radiation with diverse colour patterns despite remarkably low genetic differentiation across species. Cross-species colour variation in each plumage patch is associated with unique combinations of variants at a few genomic regions, which include mostly non-coding (presumably regulatory) areas close to known pigmentation genes. Genotype–phenotype associations can vary depending on patch colour and are stronger for eumelanin pigmentation, suggesting eumelanin production is tightly regulated. Although some genes are involved in colour variation in multiple patches, in some cases, the SNPs associated with colour changes in different patches segregate spatially. These results suggest that coloration patterning in capuchinos is generated by the modular combination of variants that regulate multiple melanogenesis genes, a mechanism that may have promoted this rapid radiation.

Comparative Characterization of Eastern Carrot Accessions for Some Main Agricultural Traits

Background: Unevaluated open-pollinated germplasm represents a promising source of variability to face the problems of worldwide food production under a changing environment. In carrots, this is particularly true for black carrot accessions, which are the most relevant among Eastern carrot germplasm due to their high anthocyanin content and, concomitantly, antioxidant capacity. Methods: In the present work, a comparative characterization was conducted for the first time on 11 Eastern carrot landraces and Night Bird ‘F1’ as the reference cultivar, grown under glasshouse conditions at temperatures up to 33 °C. Results: Some landraces showed their potential for ulterior evaluation in terms of plant and taproot size, plant compactness, specific leaf area and leaf area ratio, among other traits. The highest anthocyanin and flavonoid contents were found in the reference cultivar, whereas remarkable differences in these variables were observed for the rest of accessions, which in turn may correlate with very distinct coloration patterns. Premature bolting and taproot shape abnormalities were also recorded. Mineral composition analysis showed the nutritional potential of Eastern carrot leaves, which displayed higher concentration than taproot tissue for several macro- and micronutrients. Moreover, several accessions had higher nutrient concentrations than the reference cultivar, which also highlights their profitability. Conclusions: This work contributes to the knowledge on Eastern black carrot germplasm by characterizing some of its main agricultural traits, and opens up the prospect for complementary evaluation on high-yield accessions.

Use of Different Metal Oxide Coatings in Stainless Steel Based ECDs for Smart Textiles

Electrochromism is the ability of a material to selectively change its coloration under the influence of an external electric current/potential and maintain it even after the power source has been disconnected. Devices that use such a mechanism are known as electrochromic devices (ECDs). Over the years, significant effort has been invested into the development of flexible ECDs. Such electrochromic tapes or fibers can be used as smart textiles. Recently, we utilized a novel geometrical approach in assembling electrochromic tapes which does not require the use of optically transparent electrodes. The so-called inverted sandwich ECD configuration can employ various color-changing mechanisms, e.g., intercalation, redox reactions of electrolytes or reactions on electrode surfaces. One of the most frequently used electrochromic metal oxides is WO3. However, other metal oxides with different coloration responses also exist. In this paper, we explore the use of V2O5 and TiO2 in metal-tape-based ECDs in the inverted sandwich configuration and compare their performance with WO3-based devices. Morphological features of metal oxide thin layers were investigated with scanning electron microscopy (SEM), and the performance of the tapes was investigated electrochemically and spectroscopically. We demonstrate that well-established preparation techniques (e.g., sol–gel synthesis) along with coating approaches (e.g., dipping) are adequate to prepare optically nontransparent fiber electrodes. Depending on the metal oxide, flexible electrochromic fiber devices exhibiting different coloration patterns can be assembled. Devices with TiO2 showed little coloration response, while much better performance was achieved in the case of V2O5 and WO3 ECDs.

Genetics of white color and iridophoroma in “Lemon Frost” leopard geckos

The squamates (lizards and snakes) are close relatives of birds and mammals, with more than 10,000 described species that display extensive variation in a number of important biological traits, including coloration, venom production, and regeneration. Due to a lack of genomic tools, few genetic studies in squamates have been carried out. The leopard gecko, Eublepharis macularius, is a popular companion animal, and displays a variety of coloration patterns. We took advantage of a large breeding colony and used linkage analysis, synteny, and homozygosity mapping to investigate a spontaneous semi-dominant mutation, “Lemon Frost”, that produces white coloration and causes skin tumors (iridophoroma). We localized the mutation to a single locus which contains a strong candidate gene, SPINT1, a tumor suppressor implicated in human skin cutaneous melanoma (SKCM) and over-proliferation of epithelial cells in mice and zebrafish. Our work establishes the leopard gecko as a tractable genetic system and suggests that a tumor suppressor in melanocytes in humans can also suppress tumor development in iridophores in lizards.

A Revised Description of the Larva of Leptocerina pauliani (Ross 1957 (Trichoptera: Leptoceridae), an Endemic Species of La Réunion Island

Leptocerina is an endemic Afrotropical genus of Trichoptera, with 19 species documented but only five partially described at the larval stage. The first description of Leptocerina pauliani (Ross 1957) larva by Marlier & Marlier (1982) included very few illustrations, making comparisons with other species challenging. I present a revised description of the L. pauliani larval stage, using specimens collected from the River Marsouins in La Réunion Island. I apply a focus stacking approach for emphasizing coloration patterns and providing a detailed description of larval characters. Criteria for distinguishing L. pauliani from the other species of Leptocerina already described or partially described for the larval stage are discussed.

Taxonomic key to the snakes (Squamata: Ophidia) species of the Itajaí Valley, Santa Catarina, Brazil

Snakes represent the richest Reptile group in Brazil, amounting to 412 species and 40% of them are endemic for the country. This great richness combined with the poor taxonomic knowledge makes the identification a difficult process. To correctly identify a specimen, guides, taxonomic revisions, identification keys, and consulting specialists are the most used methods. Identification keys are based on separation and segregation of characters, where the chosen paths lead to the appropriate taxa. These tools are normally used by students and non-taxonomists. Also, they can be very helpful with the general public, where they can identify the species with simple characters. This study aims to develop keys for the snakes from the State of Santa Catarina state, Brazil, focusing on the Itajaí Valley species. We surveyed 351 specimens deposited in Universidade Regional de Blumenau Zoological Collection (CZFURB), Universidade Federal de Santa Catarina (CHUFSC), and Natural History Museum of Capão da Imbuia (MHNCI) herpetological collections. Characters including pholidosis, dentition, and coloration patterns were examined from the 46 snake species registered from Itajaí Valley.

The larva of Rhyacophila albardana McLachlan 1879, including a discriminatory matrix to the Rhyacophila larvae with comb-shaped gills of Austria, Germany and Switzerland (Rhyacophilidae, Trichoptera)

Final instar larvae collected in the Rißbach (Isar catchment, Bavaria) were positively associated with adults of Rhyacophila albardana by barcoding; final instar larvae and adults of this species also were collected at the same time and site in the Lech River (Austria) in the absence of confusing species. These collections and associations enabled a description of the hitherto unknown larva of this species. We present information on the morphology of the larva and illustrate the most important diagnostic features. This dataset is included in a discriminatory matrix of the other larvae with comb-shaped gills (Rhyacophila Hyperrhyacophila Group) known so far from Austria, Germany, and Switzerland. Species can be separated by coloration patterns of the head and prosternum morphology. Rhyacophila albardana is known from Austria, France, Germany, Italy, and Switzerland (Neu et al. 2018).

Genetics of white color and iridophoroma in "Lemon Frost" leopard geckos

Coloration patterns promote survival and reproductive success in the animal kingdom. Despite their importance, wide gaps exist in our understanding of the genetic and evolutionary mechanisms that underpin them. The leopard gecko, Eublepharis macularius, is a popular companion animal, and displays a variety of coloration patterns. We investigated a spontaneous semi-dominant mutation, known as "Lemon Frost", that causes extensive white color in leopard gecko skin. Although "Lemon Frost" individuals are aesthetically appealing, more than 80% of them develop tumors of white color (i.e., iridophoroma) 0.5 to 5 years after birth. To identify the gene that regulates white color and is likely also responsible for the iridophoroma, we genotyped 220 animals, including 33 homozygous mutants, with short-read sequencing. We used synteny, linkage analysis and homozygosity mapping to localize the mutation to a strong candidate gene, SPINT1, a tumor suppressor previously implicated in human skin cutaneous melanoma (SKCM) as well as in over-proliferation of epithelial cells in mice and zebrafish. Our work establishes the leopard gecko as a tractable genetic system and suggests that a tumor suppressor in melanocytes in humans can also suppress tumor development in iridophores in lizards.