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In the Neotropical Region, the mosquitoes, grouped in the tribe Sabethini (Arthropoda, Insecta, Diptera: Culicidae) are considered of medical importance by the role that some species may have in arbovirus transmission; also, because they are good bioindicators. More than 400 species are currently recognised and are mainly associated with forest areas. The tribe Sabethini is poorly studied and the information about diversity and distribution for species relating to it is scarce. In Colombia, 54 species of the tribe are known; however, several geographical areas have not been included in the studies for this group and data for recent field collections are not available; therefore, the records are outdated. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The Colombian Bajo Cauca region is an important malaria endemic area. • A variety of human activities seems to influence Anopheles species composition. • Larval habitats derived from human activities facilitated vector establishment. • Anopheles nuneztovari , An. darlingi and An. braziliensis were the most abundant species. Abstract Environmental variations associated with alterations derived from human activities affect mosquito abundance and composition. The objective of this study was to evaluate species abundance, composition, biting behavior and human biting rates for Anopheles specimens collected in localities of an important malaria endemic region in NW Colombia. A total of 2041 specimens belonging to nine species were collected in six malaria endemic localities of the Bajo Cauca region. Anopheles braziliensis was the most abundant species (n = 850, 41.7%) and exhibited the highest human biting rate (64.8 b.p.n), followed by the primary vectors Anopheles nuneztovari (n = 614, 30%) and Anopheles darlingi (n = 368, 18%). Biting activity of the main malaria vectors An. nuneztovari and An. darlingi and the opportunistic species An. braziliensis suggests high biting exposure for humans, mainly from 19:00 h to 23:00 h, and therefore, increased malaria risk at these hours. Regarding mosquito species, Puerto Astilla locality in Nechí municipality exhibited the highest α diversity, but in general, diversity in all localities was low. This information provides the bases for the implementation of targeted and effective vector control interventions directed to reduce human vector-contact. [ABSTRACT FROM AUTHOR]

Anopheles nuneztovari is an important Colombian malaria vector widespread on both sides of the Andean Mountains, presenting morphological, behavioral and genetic heterogeneity throughout the country. The aim of this study was to evaluate whether the population structure and distribution of An. nuneztovari in Colombia are associated with ecological and physical barriers present in a heterogeneous landscape. Further, differences in behavior were addressed. A total of 5392 specimens of An. nuneztovari were collected. Mitochondrial and nuclear marker analyses detected subdivision among the northwest-west, northeast and east populations. For both markers, isolation by distance (~ 53%) and isolation by resistance (> 30%) were determinants of population genetic differentiation. This suggests that physical barriers, geographical distance and ecological differences on both sides of the Andean Mountains promoted the genetic differentiation and population subdivision of An. nuneztovari in Colombia. This species showed the highest biting activity after 20:00 h; indoor and outdoor preferences were found in all localities. These results indicated that the most effective interventions for controlling vector populations on both sides of the Andes need to be region-specific. [ABSTRACT FROM AUTHOR]

Abstract The Arribalzagia Series of the Anopheles Subgenus comprises morphologically similar species or members of species complexes which makes correct species identification difficult. Therefore, the aim of this work was to discriminate the morphospecies of the Arribalzagia Series present in Colombia using a multilocus approach based on ITS2, COI and CAD sequences. Specimens of the Arribalzagia Series collected at 32 localities in nine departments were allocated to seven species. Individual and concatenated Bayesian analyses showed high support for each of the species and reinforced the previous report of the Apicimacula species Complex with distribution in the Pacific Coast and northwestern Colombia. In addition, a new molecular operational taxonomic unit-MOTU was identified, herein denominated near Anopheles peryassui , providing support for the existence of a Peryassui species Complex. Further, the CAD gene, just recently used for Anopheles taxonomy and phylogeny, demonstrated its power in resolving phylogenetic relationships among species of the Arribalzagia Series. The divergence times for these species correspond to the early Pliocene and the Miocene. Considering the epidemiological importance of some species of the Series and their co-occurrence in malaria endemic regions of Colombia, their discrimination constitutes an important step for vector incrimination and control in the country. Highlights • Species of the Arribalzagia Series were discriminated by a multilocus approach. • The CAD gene evidenced phylogenetic relationships among these species. • The existence of the Apicimacula Complex was corroborated. • A new MOTU near Anopheles peryassui was detected in NW Colombia. [ABSTRACT FROM AUTHOR]

• Anopheles nuneztovari had the highest human biting rate in a Pacific region locality. • Anopheles darlingi had the highest human biting rate in a Bajo Cauca locality. • Detection of blood feeding sources showed that humans were the most common host. • Anopheles nuneztovari showed a preference for feeding on dogs. • An. darlingi showed preference for pigs, dogs and Galliformes, rather than humans. Malaria is an important public health problem, caused by Plasmodium parasites which are transmitted by female Anopheles mosquitoes that bite humans to obtain blood. The aim of this work was to identify the blood feeding sources of Anopheles female mosquitoes and calculate their entomological indices in relation to Plasmodium transmission. Mosquitoes were collected in malaria endemic localities of the Bajo Cauca and Pacific regions of Colombia using human landing catch and barrier screens, from 18:00 to 24:00 hr, in 2018–2021. Animal censuses within a radius of ∼250 m were carried out at each sampling site. A total of 2018 Anopheles specimens were collected and the most abundant species were Anopheles (Nys.) darlingi and Anopheles (Nys.) nuneztovari. The highest human biting rate was 77.5 bites per person per night (b/p/n) for An. nuneztovari in Córdoba-Pacific and 17.5 b/p/n for An. darlingi in Villa Grande-Bajo Cauca. Both species were active mainly in indoor unwalled rooms of the houses. Only An. nuneztovari from Córdoba-Pacific was infected with Plasmodium , with an entomological inoculation rate of 91.25 infective bites per year. Detection of blood feeding sources demonstrate that humans were the most common host, however, An. nuneztovari showed a preference for feeding on dogs and An. darlingi on pigs, dogs and Galliformes, rather than humans. These results contribute to entomological surveillance information and provide valuable data that can be used to tailor effective control interventions to minimize human-vector contact in these malaria endemic regions. [ABSTRACT FROM AUTHOR]