Introduction and importance Gallstone ileus is an uncommon complication of cholelithiasis. It is usually presented as a small bowel obstruction. Elderly patients are commonly affected. The diagnosis is challenging, since needs a high index of suspicion and imagenology is key. Surgery is the mainstay management, most commonly performed by laparotomy, but laparoscopy is summing cases. Nevertheless the approach is still controversial. We report a gallstone ileus case, that was managed totally laparoscopic in our medium complex public institution. Case presentation An 71 years-old male patient, with symptomatic cholelithiasis, consulted in emergency department with symptoms and signs of small bowel obstruction. Computed tomography of abdomen and pelvis showed the classical Rigler's triad. Totally laparoscopic enterolithotomy alone was performed successfully. Postoperative evolution was without incidents, being discharge at fifth day. Clinical discussion Gallstone ileus represents around 0,3–0,5% of cholelithiasis complications. Mostly affect elderly women patients, with comorbidities. Mortality and morbidity is still high nowadays. The classical management of gallstone ileus is the open surgery, but the laparoscopic approach has been described and it can be done. Conclusion The laparoscopic management of gallstone ileus is effective and secure procedure and seems reasonable to attempt if the conditions and skills are available.

Despite its theoretical relationship, the effect of body size on the performance of species distribution models (SDM) has only been assessed in a few studies, and to date, the evidence shows unclear results. In this context, Chilean fishes provide an ideal case to evaluate this relationship due to their short size (fishes between 5 cm and 40 cm) and conservation status, providing evidence for species at the lower end of the worldwide fish size distribution and representing a relevant management tool for species conservation. We assessed the effect of body size on the performance of SDM in nine Chilean river fishes, considering the number of records, performance metrics, and predictor importance. The study was developed in the Bueno and Valdivia basins of southern Chile. We used a neural network modeling algorithm, training models with a cross-validation scheme. The effect of fish size on selected metrics was assessed using linear models and beta regressions. While no relationship between fish size and the number of presences was found, our results indicate that the model specificity increases with fish size. Additionally, the predictive importance of Riparian Vegetation and Within-Channel Structures variables decreases for larger species. Our results suggest that the relationship between the grain of the dataset and the home range of the species could bias SDM, leading in our case, to overprediction of absences. We also suggest that evolutionary adaptation to low slopes among Chilean fishes increases the relevance of riparian vegetation in the SDMs of smaller species. This study provides evidence on how species size may bias SDM, which could potentially be corrected by adjusting the model grain.

Highlights

Despite its theoretical relationship, the effect of body size on the performance of species distribution models (SDM) has only been assessed in a few studies of terrestrial taxa. We aim to assess the effect of body size on the performance of SDM in river fish. We study seven Chilean freshwater fish, using models trained with three different sets of predictor variables: ecological (Eco), anthropogenic (Antr) and both (Eco+Antr). Our results indicate that the performance of the Eco+Antr models improves with fish size. These results highlight the importance of two novel predictive layers: the source of river flow and the overproduction of biotopes by anthropogenic activities. We compare our work with previous studies that modeled river fish, and observe a similar relationship in most cases. We discuss the current challenges of the modeling of riverine species, and how our work helps suggest possible solutions.

Despite its theoretical relationship, the effect of body size on the performance of species distribution models (SDM) has only been assessed in a few studies of terrestrial taxa. We aim to assess the effect of body size on the performance of SDM in river fish. We study seven Chilean freshwater fish, using models trained with three different sets of predictor variables: ecological (Eco), anthropogenic (Antr) and both (Eco+Antr). Our results indicate that the performance of the Eco+Antr models improves with fish size. These results highlight the importance of two novel predictive layers: the source of river flow and the overproduction of biotopes by anthropogenic activities. We compare our work with previous studies that modeled river fish, and observe a similar relationship in most cases. We discuss the current challenges of the modeling of riverine species, and how our work helps suggest possible solutions.