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One hundred eighty-three individuals of Glossogobius aureus, native to Lake Taal, Philippines, were collected in 2021–2022. Of these, 4 endohelminths were found and identified: Andracantha gravida (Acanthocephala: Polymorphidae), Schyzocotyle acheilognathi (Platyhelminthes: Bothriocephalidae), Azygia sp. (Platyhelminthes: Azygiidae), and Opegaster minima (Platyhelminthes: Opecoelidae). These helminths represent new host records for G. aureus and provide novel contributions to the recent Philippine parasite biodiversity listing. Among these 4 helminths, Azygia sp. was the most prevalent, had the highest percent dominance and mean intensity, and had a broader range followed by S. acheilognathi, A. gravida, and O. minima, respectively. These findings highlight the need to further explore Lake Taal's parasitofauna, especially with regard to the invasion of S. acheilognathi, and the transmission specificity of O. minima, which can be utilized as a keystone parasite biomarker and in return aid in the management and conservation efforts in Lake Taal. [ABSTRACT FROM AUTHOR]

Lotic ecosystems in urban areas are severely impacted by anthropogenic environmental stressors, such as deforestation and nutrient pollution, due to socioeconomic activities in the catchment. To work out measures for identification and mitigation of concurrent multiple stressors to a stream system, it is necessary to assess the relative importance of impacts by the individual stressors. Here we aimed to discriminate the covarying effects of nutrient pollution and deforestation on benthic macroinvertebrate communities in an urbanised tropical stream system. In the Silang-Santa Rosa Subwatershed (SSRS) of Laguna de Bay, benthic macroinvertebrates and physicochemical environments were investigated at 13 sites varying in human population density, riparian canopy, and land-use pattern as indicated by geographic information systems in the catchment. Regression and multivariate analyses were performed to identify the drivers of the biodiversity loss and understand its underlying mechanisms. In the SSRS, where rapid economic growth took place without updating poorly installed wastewater treatment plants (WWTPs), domestic activity indicated by human population density in the catchment was the primary factor in generating heavy phosphorous loadings (mean total phosphorus = 0.91; range = 0–1.50 mg/l) that caused hypoxia (mean dissolved oxygen = 2.98; range = 0.13–6.27 mg/l) in stream waters and subsequently reduced macroinvertebrate diversity (mean H' = 0.91; SD ± 0.61). Nutrient and organic pollution and riparian deforestation explained 53.5% and 9.7% of the variation of benthic macroinvertebrate communities in SSRS, respectively. Given such scenario, additional WWTPs servicing urban developments and improved riparian canopy cover in the SSRS can be both strategic and cost-effective in the initial steps of environmental mitigation in urbanised streams, especially in rapidly developing countries. [ABSTRACT FROM AUTHOR]

We performed the first host-parasite survey of the Philippine crocodile, Crocodylus mindorensis , a critically endangered species for which ecological information is lacking. We collected by gastric lavage samples of the stomach contents of crocodiles (n = 10) residing at the Palawan Wildlife Rescue and Conservation Center in Puerto Princesa, Palawan, Philippines. The only parasite detected was an acanthocephalan, which was identified as Neorhadinorhynchus nudus (n = 68), a parasite typically found in the marine fish species consumed by three crocodile individuals. Given the known hosts of N. nudus , its parasitism of C. mindorensis in captivity is likely established by consumption of marine fish. Our findings have implications for the conservation management of C. mindorensis , particularly in terms of preventing introduction of parasites that could lead to development of infectious disease or alter the fitness of captive animals. Unlabelled Image • The first to record parasite of the gastrointestinal tract of Philippine crocodile • Three Crocodylus mindorensis were parasitized by one species of acanthocephalan • The parasite was identified as Neorhadinorhynchus nudus , a parasite of marine fish [ABSTRACT FROM AUTHOR]