Physical and genetic maps have been used for chromosomal localization of genes in vectors of infectious diseases. The availability of polytene chromosomes in malaria mosquitoes provides a unique opportunity to precisely map genes of interest. We report physical mapping of two actin genes on polytene chromosomes of the major malaria vector in Amazon Anopheles darlingi. The clones with the actin genes sequences were obtained from a cDNA library constructed from RNA isolated from adult females and males of An. darlingi. Each of the two clones was mapped to a unique site on the chromosomal arm 2L in subdivisions 21A (clone pl05-A04) and 23B (clone pl17-G06). The obtained results together with previous mapping data provide a suitable basis for comparative genomics and for establishing chromosomal homologies among major malaria vectors.

In this work we characterise the properties of the object SDSS J020536.84-081424.7, an extended nebular region with projected extension of 14 × 14 kpc$\rm ^2$ in the line of sight of the ETG Mrk 1172, using unprecedented spectroscopic data from MUSE. We perform a spatially resolved stellar population synthesis and estimate the stellar mass for both Mrk 1172 (1 × 1011 M⊙) and our object of study (3 × 109 M⊙). While the stellar content of Mrk 1172 is dominated by an old (∼ 10 Gyr) stellar population, the extended nebular emission has its light dominated by young to intermediate age populations (from ∼ 100 Myr to ∼ 1 Gyr) and presents strong emission lines such as: Hβ, [O iii] λ, λ4959, 5007Å, Hα, [N ii] λ, λ6549, 6585Å and [S ii] λ, λ6717, 6732Å. Using these emission lines we find that it is metal-poor (with Z ∼ 1/3 Z⊙, comparable to the LMC) and is actively forming stars (0.70 M⊙ yr−1), especially in a few bright clumpy knots that are readily visible in Hα. The object has an ionised gas mass ≥3.8 × 105 M⊙. Moreover, the motion of the gas is well described by a gas in circular orbit in the plane of a disk and is being affected by interaction wtih Mrk 1172. We conclude that SDSS J020536.84-081424.7 is most likely a dwarf irregular galaxy (the dIGal).

We present a spatially resolved stellar population analysis of 61 jellyfish galaxies and 47 control galaxies observed with ESO/MUSE attempting to understand the general trends of the stellar populations as a function of the stripping intensity and mass. This is the public sample from the GASP programme, with 0.01 < z < 0.15 and 8.9 < log (M⋆/M⊙) < 12.0. We apply the spectral population synthesis code fado to fit self-consistently both the stellar and nebular contributions to the spectra of the sources. We present 2D morphological maps for mean stellar ages, metallicities, gas-phase oxygen abundances, and star formation rates for the galaxies with Integrated Nested Laplace Approximation (inla), which is efficient in reconstructing spatial data of extended sources. We find that “extreme stripping” and “stripping” galaxies are typically younger than the other types. Regarding stellar and nebular metallicities, the “stripping” and “control passive” galaxies are the most metal-poor. Based on the phase space for jellyfish cluster members we find trends in ages, metallicities, and abundances with different regions of the diagram. We also compute radial profiles for the same quantities. We find that both the stripping and the stellar masses seem to influence the profiles, and we see differences between various groups and distinct mass bins. The radial profiles for different mass bins present relations already shown in the literature for undisturbed galaxies, i.e., profiles of ages and metallicities tend to increase with mass. However, beyond ∼0.75 effective radius, the ages of the most massive galaxies become similar to or lower than the ages of the lower mass ones.

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Jellyfish are the most extreme cases of galaxies undergoing ram-pressure stripping. In order to analyse the stellar populations distribution along these galaxies, we have performed stellar population synthesis in data cubes of jellyfish from the GASP programme, using both Starlight and FADO codes.