The tiger shrimp Penaeus monodon is a native species of the Indo-Pacific Ocean that was introduced to promote its cultivation in several American countries, including Colombia. As a result of inappropriate aquaculture practices, it has established itself in the wild in almost all the Colombian Caribbean Sea. To evaluate the genetic diversity, population structure, and origin of the founder populations, samples from three sites in the Colombian Caribbean were analyzed from 10 microsatellite loci and the mitochondrial DNA Control Region. Genetic diversity similar to native populations was found to be present in three relatively discrete populations and their origin is related to natural populations from Thailand, the Philippines, Taiwan and China. We discuss how oceanographic conditions and culture systems of tiger shrimp facilitated the success of biological invasion processes in marine ecosystems of the Colombian Caribbean.

The comparative phylogeography of marine species with contrasting dispersal potential across the southern Caribbean Sea was evaluated by the presence of two putative barriers: the Magdalena River plume (MRP) and the combination of the absence of a rocky bottom and the almost permanent upwelling in the La Guajira Peninsula (ARB + PUG). Three species with varying biological and ecological characteristics (i.e., dispersal potentials) that inhabit shallow rocky bottoms were selected: Cittarium pica (PLD < 6 days), Acanthemblemaria rivasi (PLD < 22 days), and Nerita tessellata (PLD > 60 days). We generated a set of SNPs for the three species using the ddRad-seq technique. Samples of each species were collected in five locations from Capurganá to La Guajira. For the first time, evidence of a phylogeographic break caused by the MRP is provided, mainly for A. rivasi (AMOVA: Φ_CT = 0.420). The ARB + PUG barrier causes another break for A. rivasi (Φ_CT = 0.406) and C. pica (Φ_CT = 0.224). Three populations (K = 3) were identified for A. rivasi and C. pica, while N. tessellata presented one population (K = 1). The Mantel correlogram indicated that A. rivasi and C. pica fit the hierarchical population model, and only the A. rivasi and C. pica comparisons showed phylogeographic congruence. Our results demonstrate how the biological traits of these three species and the biogeographic barriers have influenced their phylogeographic structure.

Pneumonia caused by Pneumocystis jirovecii poses a serious threat, particularly to immunocompromised patients such as those with HIV/AIDS, transplant recipients, or individuals undergoing chemotherapy. Its diagnosis is challenging because current methods, such as microscopy and certain molecular tests, have limitations in sensitivity and specificity, and require specialized equipment, which delays treatment initiation. In this context, CRISPR-Cas12-based methods offer a promising alternative: they are rapid, highly specific, sensitive, and low-cost, enabling more timely and accessible detection, even in resource-limited settings. We developed a simple and rapid detection platform based on the CRISPR-Cas12 coupled with lateral flow strips. A guide RNA was designed against DHPS, β-tubulin, and mtLSU rRNA genes. The guide corresponding to β-tubulin showed high sensitivity in the detection of P. jirovecii to produce a detectable fluorescence signal within the first 20–30 min. In addition, it demonstrated high specificity for P. jirovecii when DNA from other microorganisms was used. When coupled with lateral flow strips, high sensitivity and specificity were also observed for detecting positive samples, without the need for genetic amplification. CRISPR-Cas12 successfully detected P. jirovecii infection in an initial diagnostic application, demonstrating the potential of this method for integration into public health diagnostic systems, particularly in field, due to its adaptability, speed, and ease of use.