Arthropoda, Volume 4, Issue 2 (June 2026) – 5 articles

In this contribution, we describe a new species from the Estación de Biología Chamela (IBUNAM), located in Jalisco, Mexico. Mastigoproctus claritae sp. nov. has a stridulatory organ like M. mexicanus and M. xetame. However, it is distinguished from these species by the presence of a proventral marginal smooth keel in the chelicerae, a retrolateral surface pedipalp femur with congregated and blunt cristulae, a prodorsal margin spine S3 that is longer than the other spines in males, and symmetric, peanut-shaped spermatheca seminal receptacles in females. Mastigoproctus claritae sp. nov. represents the twenty-third species of the genus and the twelfth species documented in Mexico. Full article

Balancing of macronutrient intake assumes that animals change their food preferences to increase consumption of the deficient nutrients and/or decrease consumption of nutrients in excess. Harvestmen are generalist predators that consume mostly soft-bodied insects, but they supplement this with plant-derived food such as berries (omnivory). In spite of this, they are often carbohydrate-limited in their natural habitats. As aphids have higher sugar content than most other insect prey, they are a potential source of sugar. We hypothesized that sugar-deficient harvestmen have increased preference for aphids relative to other insect prey (fruit flies) and consume more aphids than sugar-satiated harvestmen. Likewise, we hypothesized that protein-deficient harvestmen would show increased consumption of aphids relative to a pure sugar source (dried grape pulp). The former hypothesis was confirmed but the latter was not. Carbohydrate-deprived harvestmen (Leiobunum gracile) consumed 1.9 times more aphids than nutritionally balanced ones (p = 0.0004). Consumption of dried grape was increased in carbohydrate-deficient harvestmen, while protein deficiency did not increase consumption of aphids. These results indicate that aphids may be used as a carbohydrate source if no better alternative is available, but they are unable to relieve a deficiency in protein. We suggest that carbohydrate deprivation in predators may enhance aphid control. Full article

Kroyeria species (Siphonostomatoida: Kroyeriidae) are currently represented by 20 valid species. One of these is K. minuta described from the milk shark off India. However, the original description has some uncertainties and atypical features and therefore a re-description is needed. Kroyeria species were collected from milk sharks off South Africa, and amongst these were some specimens of K. minuta as well as a new species of Kroyeria. This work therefore combines a re-description of K. minuta as well as a description of K. confusa n. sp. from the milk shark off South Africa. The most distinguishing feature of K. minuta is the structure of the legs, especially that of leg 2 in the female. The new species shares characteristics with K. rhophemophaga and K. triakos but differs mainly with respect to the morphology of the legs. Thus, the number of valid Kroyeria species is now 21, and the number of reported Kroyeria species from South African waters increases to 13 with the addition of K. confusa n. sp. and the newly reported K. minuta. Full article

Environmental DNA (eDNA) offers a promising, non-invasive approach for monitoring infectious agents in aquaculture. While molecular techniques for detecting shrimp pathogens are well established in host tissues, there is a lack of standardized protocols for pathogen detection from environmental samples using conventional PCR. In this study, we developed and validated a universal conventional PCR protocol for monitoring DNA from major viral and bacterial shrimp pathogens within pond water and sediment samples. The method was applied to two commercial shrimp farms in Mexico, where eDNA was extracted from field-collected water and sediment. Using published primer sets, we successfully amplified DNA sequences corresponding to six key pathogens—Infectious hypodermal and hematopoietic necrosis virus (IHHNV), Baculovirus penaei (BP), Monodon baculovirus (MBV), Shrimp hemocyte iridescent virus (SHIV), Candidatus Hepatobacter penaei (NHP-B), and Acute hepatopancreatic necrosis disease (AHPND)-causing Vibrio spp.—in environmental samples. Sequencing of PCR amplicons confirmed 93–100% identity to previously reported pathogen strains, highlighting the method’s reliability. Pathogen detection rates varied by site, sample type, and date, with the percentage of positive samples ranging from 11.1% to 77.7%. Notably, this is the first report of SHIV DNA detection from environmental samples in the Americas, highlighting its value for pathogen surveillance even in the absence of documented outbreaks. This protocol offers a cost-effective and scalable tool for pathogen surveillance in shrimp aquaculture, enhancing early disease detection and contributing to improved biosecurity and risk assessment frameworks. Full article

Five new species of Schizomida are described from the Ecuadorian Andes and the Amazonian ecoregion in three different genera: in Colombiazomus, Colombiazomus karsticus n. sp. (female); in Hansenochrus, Hansenochrus maicun. sp. (male) and Hansenochrus pastaza n. sp. (female); and in Surazomus, Surazomus colonso, n. sp. (male, female) and Surazomus yasunin. sp. (male, female). A distribution map of all newly described species is presented. Full article