Cucurbita pepo L. (Cucurbitaceae) was an integral component of the diet of Pre-Columbian Mesoamerican cultures and is an important cash crop with high cultural value in contemporaneous indigenous populations of Guatemala. Despite the increasing attention to native bees as pollinators of cucurbit crops, little is known about the diversity of bees that visit or pollinate these crops in many regions. Based on collections from 11 observational plots of C. pepo established in five localities and maintained by the local community across the Cloud Forest Corridor in Guatemala, we documented 27 bee species belonging to 14 genera in Apidae and Halictidae as floral visitors. Species composition was significantly different among plots and among localities; however, honey bees (Apis mellifera Linnaeus, 1758) (Apidae: Apini) and the stingless bee Partamona bilineata (Say, 1837) (Apidae: Meliponini) were the most abundant flower visitors in all plots and localities, accounting up to 80% of the total number of visits. Two species of squash bees were recorded, Peponapis apiculata (Cresson, 1878) and P. limitaris (Cockerell, 1906) (Apidae: Eucerini), but they were rare (3.4% of total number of specimens) across all plots and localities. Based on pollinator exclusion experiments as well as comparisons of fruit weight and seed number and weight, we confirmed the dependence of this crop on insect pollination and the role of honey bees and P. bilineata as main pollinators in the observational plots. Surveys of bees in the surrounding vegetation of the plots indicated a higher diversity (36 species of 28 genera) than in the plots; about 40% of these species are also common visitors of flowers of C. pepo.

Cases of final instar larvae of Brachycentrus kuwayamai Wiggins, Tani and Tanida, 1985 and B. americanus (Banks, 1899) (Brachycentridae) were observed in Hokkaido, northern Japan. Their cases were four-sided, tapered, and constructed of transversely arranged, narrow pieces of plant materials. Slender leaf pieces were fastened longitudinally on cases of final instar larvae of B. kuwayamai, but not on those of B. americanus. In B. kuwayamai, occurrence of the long pieces was variable in populations, with only 1–4 pieces on 32% of the larvae at one site, but 4–18 pieces on 100% of the larvae at another site. The longest attached piece was 3×the case length, and 23 pieces was the most found attached to a single case. This is the first report of attachment of long vegetal pieces to larval cases in the Brachycentridae.

The behavioral and ecological activities of Tachysphex tarsatus (Say, 1823), T. miwok Pulawski, 1988, T. musciventris Pulawski, 1982, and T. clarconis Viereck, 1906 were studied in spring 2010–2014 at Montana de Oro State Park and El Moro Elfin Forest, San Luis Obispo County, California. Adult wasps were active from late February (T. miwok)-March (T. miwok, T. clarconis, T. tarsatus) to April-early May (T. miwok)-late June (T. clarconis, T. tarsatus) in association with ample seasonal rainfall, moist malleable sand, reduced coastal fog, increased sunshine, flush of low growth flowering plants, and abundance of nymphal prey Caelifera (Orthoptera). The absence of these species in summer 2009–2014 was probably related to extremely limited rainfall, dry loose sand, frequent coastal fog, senescence of flowering plants, and substantially reduced number of nymphal prey Caelifera. Tachyphex amplus was active from July to September 2011–2012 under droughty summer climatic conditions. The five species have adapted to a treeless environment, moderately windy (13–24 mph) maritime climate, periodic fog, cool spring temperatures, and rainfall-deprived summers. Tachysphex miwok was univoltine and provisioned nests with early instar nymphal Conozoa texana (Bruner, 1889) and Oedaleonotus phryneicus Hebard, 1919 (Acrididae). Tachysphex tarsatus was uni- or bivoltine and stocked late instar nymphs and adults of the same acridid species in its nests. Tachysphex clarconis was also uni- or bivoltine but polyphagous, provisioning its nests with two families (Eumastacidae, Acrididae) and six genera of Caelifera. Eumastacidae (Morsea californica Scudder, 1898) is reported as a new host family for the genus Tachysphex in North America.

Spider-hunting wasps Trypoxylon (Trypargilum) lactitarse Saussure, 1867 and T. (Trypargilum) menkeanum Coville, 1982 were studied at the Organization for Tropical Studies field station at La Selva, Costa Rica. The wasps nested in trap-nests with tube of 6.4, 8.0, or 9.5 mm diameter. Nest structure, cocoon morphology, and differences between male and female provisions are described. Brood cells of T. lactitarse were provisioned with 5 to 19 spiders and those of T. menkeanum with 4 to 24 spiders. Most spiders were immature Araneidae, especially Eustala sp., but several other families of snare-building and wandering spiders were also among the prey. Male brood cells were more frequent in small diameter nests and at the inner end of nests. Female cells were more frequent in larger diameter nests and near the entrance. Mating almost always took place in the nest immediately before oviposition, but females were still able to determine the sex of the egg. Overall, the two species appear to be in direct competition for resources.