Twenty-three species of the genera Aspistomella Hendel, 1909, Polyteloptera Hendel, 1909, and Ulivellia Speiser, 1929 occurring in South America (Colombia, Peru, Bolivia, and Brazil) form a monophyletic lineage sharing certain combinations of plesiomorphies and apomorphies with similar larval biology. The name Aspistomella Hendel, 1909 is a new senior subjective synonym of Paraphyola Hendel, 1909. The group of genera is extended by the addition of six known species, Aspistomella angustifrons (Hendel, 1909) comb. nov., A. crucifera (Hendel, 1909) comb. nov., A. lobioptera Hendel, 1909, A. heteroptera Hendel, 1909, A. lunata (Hendel, 1909) comb. nov., Polyteloptera apotropa Hendel, 1909, and Ulivellia inversa Speiser, 1929, and 17 previously unknown species. Aspistomella duo Kovac, Kameneva & V. Korneyev, sp. nov., A. enderleini Kameneva & V. Korneyev, sp. nov., A. garleppi Kameneva & V. Korneyev, sp. nov., A. obliqua Kameneva, V. Korneyev & Savaris, sp. nov., A. pachitea Kameneva & V. Korneyev, sp. nov., A. quinquincisa Kameneva & V. Korneyev, sp. nov., A. sachavaca Smit & Kameneva, sp. nov., A. schnusei Kameneva & V. Korneyev, sp. nov., A. steyskali Kameneva & S. Korneyev, sp. nov., A. teresensis Araújo, V. Korneyev & Savaris, sp. nov., A. tres Kovac, Kameneva & V. Korneyev, sp. nov., Ulivellia amnoni Smit, sp. nov., U. arcuata Kovac & Kameneva, sp. nov., U. laetitiae Smit, sp. nov., U. pseudinsolita Kameneva & V. Korneyev sp. nov., and U. tenoris Kovac & Kameneva sp. nov. are described. A key to the genera and species is given. Among the Lipsanini, this group of genera is easily recognised by the combination of an enlarged, anteriorly produced epistome (lower part of the face) and a low clypeus (in the other lipsanine genera the clypeus is high and the epistome is not enlarged), which supports its monophyly, and the differentiated short parafrontal setulae and long and strong frontal and interfrontal setae, which is a synapomorphy of a larger monophyletic lineage that also includes Chaetopsis Loew, 1868 and related taxa, as well as Amethysa Macquart, 1835, Euphara Loew, 1868 and their relatives. As far as is known, most species of this larger lineage are associated with various Poaceae plants. The species included here in the Aspistomella group are also associated with neotropical tall grasses: bamboo (Guadua) and wild cane (Gynerium). Aspistomella and Ulivellia larvae inhabit water-filled internode cavities (= “bamboo phytotelmata”) of living bamboo culms of Guadua angustifolia. Newly emerged larvae use tunnels made by lepidopteran borers (Crambidae caterpillars) to penetrate the hard bamboo walls. Aspistomella and Ulivellia larvae are saprophagous and adapted to an aquatic lifestyle. The last instar larvae jump easily and pupate in the soil. The external morphology, cuticular sensilla and cephalopharyngeal skeletons of the third instar larvae of five Aspistomella and Ulivellia species (one with unknown adult stage) were studied by light and scanning electron microscopy. The main features that allow the identification of larvae and puparia are the unique posterior spiracles and the structure of the abdominal creeping welts. The morphological characteristics of Aspistomella and Ulivellia larvae are compared with other Lipsanini and their feeding habits with other ulidiids. An identification key for Aspistomella and Ulivellia is given. The adaptations to life in bamboo phytotelmata found in both neotropical Aspistomella and Ulivellia and in oriental members of the closely related family Tephritidae are discussed.