Brendon E. Boudinot

Bio: Brendon E. Boudinot is an academic researcher from University of California, Davis. The author has contributed to research in topics: Biology & Hymenoptera. The author has an hindex of 9, co-authored 25 publications receiving 266 citations. Previous affiliations of Brendon E. Boudinot include The Evergreen State College & University of Utah.

Contributions to the knowledge of Formicidae (Hymenoptera, Aculeata): a new diagnosis of the family, the first global male-based key to subfamilies, and a treatment of early branching lineages

Abstract: The diagnosis of the Formicidae is revised, including five new, unreversed apomorphies, of which one is a unique synapomorphy. The first global male-based key to all subfamilies is provided and illustrated, and all ant subfamilies are diagnosed for males on a global scale for the first time. Three lineages of “basal ants” are assessed in detail: the Amblyoponinae, Leptanillinae, and Martialinae. The males of Martialis heureka (Martialinae) and Apomyrma (Amblyoponinae) are described. The Martialinae and Leptanillinae are diagnosed based on males, and additional diagnostic traits for the male of Amblyoponinae and worker of Martialis are provided. The placement of Scyphodon and Noonilla in the Formicidae and Leptanillinae is confirmed. Morphological characters of the Amblyoponinae, the Leptanillinae, and the Martialinae are contrasted, and potentially homologous apomorphies are signaled.

The male genitalia of ants: musculature, homology, and functional morphology (Hymenoptera, Aculeata, Formicidae)

Abstract: The genitalia of male ants are interpreted in the context of the broader Hymenoptera. For the first time muscle homologies are established for twenty six species of ants in nine subfamilies: Amblyoponinae, Cerapachyinae, Dolichoderinae, Ecitoninae, Ectatomminae, Formicinae, Leptanilloidinae, Myrmicinae and Ponerinae. Fifteen muscles in total are found in the external genitalia of male ants and all are homologous with the musculature of basal Hymenoptera (Schulmeister 2001). Secondary fusion, reduction or losses of muscles have occurred in different lineages. From generalized to derived, the functional morphology and qualitative mechanics of three taxa, Formica obscuripes Forel 1886, Messor andrei Mayr (1886) and Labidus coecus Latreille (1802) are described and compared. Special reference is made to the Ecitoninae, where the work of Birket-Smith (1981) is reinterpreted and volsellar homology is clarified. The true digitus of Labidus is revealed to be a small sclerite at the base of the distal volsellar element which is re-identified as the cuspis.

Central American ants of the genus Megalomyrmex Forel (Hymenoptera: Formicidae): six new species and keys to workers and males.

Abstract: Megalomyrmex Forel is a distinctive lineage of Neotropical ants, some of which are specialized parasites or predators of the fungus-growing ants Attini. Here we review and key the Central American fauna. Six new species are described from both female castes: M. brandaoi sp. n., M. fungiraptor sp. n., M. longinoi sp. n., M. milenae sp. n., M. megadrifti sp. n. and M. osadrifti sp. n. A worker-based key to all Central American species is presented, and all species are illustrated. Megalomyrmex drifti Kempf is redescribed and the first descriptions of queens for M. miri Brandao and M. foreli Emery are provided. New biological information, several new geographic records, and a discussion of the species-group schema of Brandao (1990) are presented. The male sex of Megalomyrmex is diagnosed at the genus-level and keyed to species for the Central American fauna, where known. The male of each species treated in the key is diagnosed, described, or redescribed. Males are known for fourteen out of twenty total Central American Megalomyrmex species. A distinct but unassociated male is described and keyed (M. male 01). The males of M. miri Brandao and M. wettereri Brandao are described for the first time, and the distinctness of these two species is confirmed. One potential synapomorphy of Megalomyrmex present in males and workers is the presence of a carina which posteriorly delimits the basalmost region of the petiolar dorsum.

Cretaceous ants shed new light on the origins of worker polymorphism.

Abstract: Polymorphism refers to two or more clearly different phenotypes coexisting in the population of a species. It has been observed and studied among ants, bees, wasps, termites, dung beetles and stag beetles (Trible and Kronauer, 2017; Zhao et al., 2019). Size and shape variation of these holometabolic insects, especially ants, usually happen in larval development rather than adult stage. Worker polymorphism, continuous variation of body sizes, is considered as a significant feature of advanced insect societies and the reason of castes differentiation in ant eusociality. Variation in individual sizes influences not only the behavioral repertoire of individuals, but also the trophic ecology, energetic efficiency of the colony (Peeters and Ito, 2015). Size-variable worker polymorphism is also associated with increased behavioral specialization and caste determination in colony (Trible and Kronauer, 2017). For example, major workers having larger body and mandibles usually take charge of defense or food transportation; but dwarf workers having smaller body usually take care of eggs and trophallaxis. However, it is hard to elucidate early polymorphism within worker caste due to sparse fossil evidence because of difficulties to identify workers to be co-species or to confirm whether they are cocolony. Engel and Grimaldi supposed that Haidomyrmex Dlussky, 1996 should be a kind of “major” worker as a subcaste of workers for its special mandibles (Engel and Grimaldi, 2005). But subsequent studies suggested that workers with such unique cranio-mandibular were common in all castes rather than “major” workers (Perrichot et al., 2008). Thus, polymorphism of worker ants has never been described in fossils hitherto. The earliest confirmed fossil ants can be dated to the late Albian (ca. 100 Mya). Several taxa of stem-group ants reported from mid-Cretaceous Burmese amber (ca. 99 Mya) suggest that the eusociality appeared at least in the midCretaceous. For example, the type species of Zigrasimecia (Barden and Grimaldi, 2013), Z. tonsora is a dealate gyne, while all specimens, reported as the other species in Zigrasimecia (Perrichot, 2014), Z. ferox are workers. Herein, we provide further characters for Z. ferox based on additional two alate specimens from Kachin (Hukawng Valley) of Northern Myanmar, ca. 99 Mya. (Figure 1A and B, Figure S1A and B in Supporting Information). We assign these two alate gynes within Zigrasimecia based on typical dense mandibular brush and clypeal combs. They differ from Z. tonsora in that Z. tonsora has a concavity on the external surface of the mandible near the apex, while these two alate gynes and workers of Z. ferox without concavity. They also conform with Z. ferox in having a steep posterior margin of the propodeum and the right angle of ventral surface of gastral segment I. Moreover, referring to venational no-

Principles of Insect Morphology

Abstract: THE author of this book ranks as the foremost American worker on insect morphology. His contributions on the subject are notable for their clarity and originality of thought, and the appearance of a volume, embodying his ideas in comprehensive form, is sure of a hearty welcome. In its preparation, Mr. Snodgrass has incorporated the results of much first-hand study with those of many recent investigators in the same field. He has produced an outstanding book wherein knowledge of facts is combined with that of function and, at the same time, theoretical conceptions of the origins and relationships of organs and parts are not overlooked. Principles of Insect Morphology By R. E. Snodgrass. (McGraw-Hill Publications in the Zoological Sciences.) Pp. ix + 667. (New York and London: McGraw-Hill Book Co., Inc., 1935.) 36s. net.

The Structure of Nematodes

Abstract: The egg the exoskeleton growth and moulting the epidermis musculature the nervous system the pseudocoelom the secretory-excretory system the digestive system the reproductive system nematode pathology.