American Museum Novitates

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The Novitates (Latin for "new acquaintances"), published continuously and numbered consecutively since 1921, are short papers that contain descriptions of new forms and reports in zoology, paleontology, and geology. New numbers are published at irregular intervals.
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    A new species of Ululodes owlfly (Ascalaphidae: Ululodinae) from Cave Creek Canyon in the Chiricahua Mountains of Arizona (American Museum novitates, no. 4010)
    (American Museum of Natural History., 2024-03-12) Jones, Joshua R.; Johnson, Samantha Valerie.; Jensen, Jeremy B.
    A new species of Ululodes owlfly from the Chiricahua Mountains of southeast Arizona is described. Support for the evolutionary independence of the species from congeners is established along two lines of evidence: statistical measures of distances among COI sequences and comparative anatomy. The new species, U. chiricahuensis, is characterized via formal description and diagnosis, images, and a distribution map. A key to the owlfly species of Cave Creek Canyon is presented. Competing hypotheses for the biogeographic origins of U. chiricahuensis are discussed, as well as possible tests for their resolution.
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    The phylogeny of the species of the genus Agelaia Lepeletier, 1836, one of the basalmost groups of Epiponini, with notes on male genitalia (Hymenoptera: Vespidae; Polistinae) (American Museum novitates, no. 4009)
    (American Museum of Natural History., 2024-02-23) Andena, Sergio Ricardo.; Noll, Fernando B. (Fernando Barbosa); Daza, Mario N.; Carpenter, James M. (James Michael), 1956-
    A cladistic analysis of the species of the Neotropical social wasp genus Agelaia Lepeletier, 1836, was performed employing female morphology and nest architecture data. Analysis resulted in a single cladogram with length 339, consistency index 0.22, and retention index 0.60, supporting Agelaia as monophyletic. Agelaia bequaerti and A. anceps are raised to specific rank. Male genitalia of A. angulata, A. areata, A. cajennensis, A. centralis, A. flavipennis, A. fulvofasciata, A. multipicta, A. ornata, A. pallipes, A. panamaenis, A. testacea, A. timida, A. vicina, and A. yepocapa are depicted and described, including comparative remarks. A revised identification key is provided.
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    An enigmatic euchelicerate from the Mississippian (Serpukhovian) and insights into invertebrate preservation in the Bear Gulch Limestone, Montana (American Museum novitates, no. 4008)
    (American Museum of Natural History., 2024-02-01) Bicknell, Russell D. C.; Kimmig, Julien.; Smith, Patrick M. (Patrick Mark); Scherer, Torsten.
    The Bear Gulch Limestone houses a diverse, exceptionally preserved marine fauna from the early Carboniferous. A wealth of vertebrate and invertebrate forms has previously been recorded from this deposit, including fish, annelids, and several arthropods. To expand the record of Bear Gulch marine arthropods, a new enigmatic, possibly blind euchelicerate, Titanoprosoma edgecombei, gen. et sp. nov., is described. The new euchelicerate taxon displays a hypertrophied, ovate, and structureless prosoma—a morphology unique among marine euchelicerates. We explore how the large prosoma and lack of ocular structures reflect possible adaptations to an infaunal, burrowing lifestyle. This species represents the fourth euchelicerate genus described from the Bear Gulch Limestone, further highlighting the impressive disparity of marine arthropods preserved in the deposit. The addition of novel invertebrate forms found in previously unknown museum material suggests that the Bear Gulch Limestone likely houses a still undocumented diversity of Carboniferous arthropods.
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    A new species of Cyphocharax Fowler (Teleostei: Curimatidae) from the Rio Xingu, Brazil (American Museum novitates, no. 4007)
    (American Museum of Natural History., 2024-01-23) Netto-Ferreira, Andre L.; Nogueira, Acácio F.; Melo, Bruno F.; Dutra, Guilherme M.
    A new species of the curimatid genus Cyphocharax is described from the Rio Xingu, Amazon basin. This species is readily distinguished from congeners by the presence of a dark, round blotch on the caudal peduncle and by the high density of iridophores on the ventrolateral portion of the body, resulting in a strongly countershaded pattern. Molecular phylogenetic analyses support the recognition of the new species and suggest that it is nested within the Curimatella alburna clade. Ancestral state reconstruction suggests independent evolutionary origins of the blotched caudal peduncle and the countershaded ventrolateral flanks among curimatid fishes.
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    A phylogenetic approach to the neotropical social wasp genus Leipomeles Möbius, 1856 (Vespidae: Epiponini), with a new identification key (American Museum novitates, no. 4006)
    (American Museum of Natural History., 2023-12-19) Somavilla, Alexandre; Santos Vieira, Gabriel; Andena, Sergio Ricardo; Noll, Fernando B. (Fernando Barbosa); Carpenter, James M. (James Michael), 1956-
    Leipomeles Möbius, 1856, is a neotropical genus of swarm-founding wasps extending from Costa Rica to the middle of Brazil, with four species described. A combined phylogenetic analysis using female and male morphology, and nest architecture was performed with the program TNT. Leipomeles is supported as monophyletic with the following relationships among species: (L. pusilla + L. albogrisea) + (L. spilogaster + L. dorsata). A new identification key for the genus is also presented.
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    A remarkable species of drosophilid fly (Diptera) with “mandibles” (American Museum novitates, no. 4005)
    (American Museum of Natural History., 2023-12-19) Grimaldi, David A.
    A distinctive species in the family Drosophilidae, Drosophila ancora Okada, 1968, is redescribed from specimens from Vietnam, and transferred to the genus Dichaetophora Duda sensu lato. It is exceptional among Diptera for its labellar sclerites that in males have grown into a pair of heavily sclerotized, pointed lobes at the tip of the labellum, producing what appear to be chewing mandibles. This is analogous to the condition in the dolichopodid Melanderia Aldrich, but there it is not sexually dimorphic. The structures are doubtfully used in male-male aggression or in postcopulatory mate guarding. Based on their shapes and fit, it is proposed that the “mandibles” are used by males to grasp the tip of the female oviscapt during courtship or for the male to grasp the female wing edge while mounted.
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    Ex vivo three-dimensional reconstruction of Acutiramus : a giant pterygotid sea scorpion (American Museum novitates, no. 4004)
    (American Museum of Natural History., 2023-11-20) Bicknell, Russell D. C.; Kenny, Katrina; Plotnick, Roy E.
    Pterygotid eurypterids include some of the largest aquatic arthropods in the fossil record and are known from middle Silurian to Middle Devonian deposits across the globe. These forms primarily preserve as mostly two-dimensional impressions, a situation that has impacted the accurate reconstruction of pterygotid ventral structures and organization. By documenting specimens displaying important dorsal and ventral structures from both Acutiramus—a larger, well-documented pterygotid genus—and other pterygotids, we reconstruct Acutiramus in three-dimensions (3D) to more thoroughly understand the functional morphology and limb arrangement of these large eurypterids. With this comprehensive 3D reconstruction, we demonstrate a much more anterior insertion of appendages II–V, a near-horizontal orientation of appendages II–VI coxae, the presence of reduced appendage II, and a labrum and epistomel region. The labrum and epistomel sections are identified as the locality for cheliceral articulation. This model also uncovers the streamlined nature and low-profile morphology of Acutiramus. We use our model to explore the morphofunctionality of pterygotid eurypterids, including their feeding strategies, addressing a conundrum inherent in previous pterygotid reconstructions.
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    Glacial relicts? A new scorpion from Mount Olympus, Greece (Euscorpiidae: Euscorpius) (American Museum novitates, no. 4003)
    (American Museum of Natural History., 2023-11-09) Blasco-Aróstegui, Javier.; Prendini, Lorenzo.
    Mediterranean mountains and Pleistocene glacial cycles are responsible for much of the unique biodiversity of the Western Palearctic, acting respectively as refugia and drivers of diversification. Mount Olympus, a legendary Greek landmark, is a perfect example. This massif provided a glacial refugium for many species, resulting in a unique biota. In the present contribution, a new euscorpiid scorpion with a distinctive morphology, Euscorpius olympus, sp. nov., is described from an isolated population in the foothills of Mount Olympus. This new species raises the number of species in the genus Euscorpius Thorell, 1876, to 74, in Greece to 32, and in the vicinity of Mount Olympus, to three. The roles of climatic oscillations, altitudinal gradients and habitat heterogeneity on the diversity and distributions of the three species occurring around Mount Olympus are briefly discussed.
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    Ancistrocerus capra (de Saussure, 1857), a valid species, not a synonym of A. antilope (Panzer, 1798) (Hymenoptera: Vespidae: Eumeninae) (American Museum novitates, no. 4002)
    (American Museum of Natural History., 2023-10-19) Fateryga, A. V. (Alexander V.), 1984-; Carpenter, James M. (James Michael), 1956-; Fateryga, Valentina V.
    Ancistrocerus capra was described by de Saussure in 1857 from North America and then was synonymized with the Palaearctic A. antilope (Panzer, 1798) by Bequaert in 1944. Although these species share a combination of two characters (impunctate and shining metapleuron and lateral surface of the propodeum and a bifurcate apex of the aedeagus) not known in other species of Ancistrocerus, they are clearly different in the structure of the clypeus (especially in the male) and the male genitalia (structure of the volsella, general shape of the aedeagus, and the structure of its ventral lobe). Thus, A. capra is again recognized as a distinct species in the present contribution. This species is distributed in the United States and Canada while A. antilope has a trans-Palaearctic distribution. Two subspecies of A. antilope known from North America are synonymized with A. capra: A. antilope navajo Bequaert, 1925 (new synonymy), and A. antilope allegrus Bequaert, 1944 (new synonymy); the taxonomic status of A. capra spenceri Bequaert, 1944, remains unclear. Bionomics of A. antilope and A. capra are similar; particularly, these species share an association with apparently the same species of symbiotic mites, Kennethiella trisetosa (Cooreman, 1942) (Sarcoptiformes: Winterschmidtiidae), and an unusual mating behavior correlated with this association (first of all, several copulations per pair). A difference, however, exists in the number of generations per year and the sex ratio: A. antilope has a single (overwintering) generation with a female-biased sex ratio while A. capra has an overwintering generation with a male-biased sex ratio and a summer one with a female-biased sex ratio.
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    On the taxonomic identity of Sturnira nana Gardner and O’Neil, 1971 (Chiroptera: Phyllostomidae), from Ecuador, with the description of a new species of Sturnira (American Museum novitates, no. 4001)
    (American Museum of Natural History., 2023-10-17) Yánez-Fernández, Viviana; Marchán-Rivadeneira, M. Raquel; Velazco, Paúl M.; Burneo, Santiago F.; Tinoco, Nicolás; Camacho, M. Alejandra
    The lesser yellow-shouldered bat, Sturnira nana, is a member of the most diverse genus of the New World leaf-nosed bats (Phyllostomidae). This species was considered endemic to Peru until 2009 when researchers captured a series of individuals in the Cordillera del Cóndor of southeastern Ecuador and identified them as S. nana. To assess the taxonomic status of this Ecuadorian population in relation to S. nana from Peru, we analyzed cytochrome b gene sequences and craniodental measurement data. In addition, we used principal component analysis to elucidate differences in climatic niches. Our analyses suggest that populations currently identified as S. nana from Ecuador and Peru are genetically, morphologically, and ecologically divergent. Herein, we formally describe the population of small Sturnira from Ecuador as a new species.
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    Systematic revision of the whip spider family Paracharontidae (Arachnida: Amblypygi) with description of a new troglobitic genus and species from Colombia (American Museum novitates, no. 4000)
    (American Museum of Natural History., 2023-06-28) Moreno-González, Jairo A.; Gutierrez Estrada, Miguel; Prendini, Lorenzo
    The ancient, enigmatic whip spider family Paracharontidae Weygoldt, 1996, representing the basalmost lineage of the arachnid order Amblypygi Thorell, 1883, is revised. The monotypic West African genus Paracharon Hansen, 1921, from Guinea Bissau, is redescribed, based on a reexamination and reinterpretation of the newly designated lectotype. A new troglobitic whip spider, Jorottui ipuanai, gen. et sp. nov., is described from a cave system in the upper basin of the Camarones River in the La Guajira Department of northeastern Colombia. This new taxon is the second extant representative of Paracharontidae and the first outside Africa. It is unambiguously assigned to the family based on several characters shared with Paracharon caecus Hansen, 1921, notably a projection of the anterior carapace margin, the tritosternum not projecting anteriorly, similar pedipalp spination, a reduced number of trichobothria on the tibia of leg IV, and cushionlike female gonopods. A detailed examination confirmed the absence of ocelli in both genera and the presence of three (Paracharon) vs. four (Jorottui, gen. nov.) prolateral teeth on the basal segment of the chelicera, the dorsalmost tooth bicuspid in both genera. The male gonopods of Paracharontidae are described for the first time. Paracharonopsis cambayensis Engel and Grimaldi, 2014, is removed from Paracharontidae and placed incertae sedis in Euamblypygi Weygoldt, 1996; amended, comparative diagnoses are presented for Paracharontidae and Paracharon; and previous interpretations of various diagnostic characters for Paracharontidae are discussed.
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    Description of two new Labeo (Labeoninae; Cyprinidae) endemic to the Lulua River in the Democratic Republic of Congo (Kasai ecoregion) : a hotspot of fish diversity in the Congo basin (American Museum novitates, no. 3999)
    (American Museum of Natural History., 2023-05-18) Liyandja, Tobit L. D.; Stiassny, Melanie L. J.
    Labeo mbimbii, n. sp., and Labeo manasseeae, n. sp., two small-bodied Labeo species, are described from the lower and middle reaches of the Lulua River (Kasai ecoregion, Congo basin) in the Democratic Republic of Congo. The two new species are members of the L. forskalii species group and are genetically distinct from all other species of that clade. Morphologically they can be distinguished from central African L. forskalii group congeners except L. dhonti, L. lukulae, L. luluae, L. parvus, L. quadribarbis, and L. simpsoni in the possession of 29 or fewer (vs. 30 or more) vertebrae and from those congeners by a wider interpectoral, among other features. The two new species are endemic to the Lulua River and, although overlapping in geographical range and most meristic and morphometric measures, are readily differentiated by differing numbers of fully developed supraneural bones, predorsal vertebrae, snout morphology, and additional osteological features. The description of these two species brings the total of Labeo species endemic to the Lulua basin to three. The third endemic species, L. luluae, was previously known only from the juvenile holotype, but numerous additional specimens have now been identified. The cooccurrence of 14 Labeo species in the Lulua River, three of which are endemic, highlights this system as a hotspot of Labeo diversity in the Congo basin and across the continent.
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    New discovery of rhyncholites and conchorhynchs (cephalopod jaw elements) from the Upper Cretaceous Mount Laurel Formation of Delaware (American Museum novitates, no. 3998)
    (American Museum of Natural History., 2023-05-10) Tajika, Amane; Anderson, Lian; Ikuno, Kenji; Landman, Neil H.; Koyasu, Hiromichi
    Rhyncholites and Conchorhynchs are the calcitic elements of upper and lower jaws of cephalopods, respectively. Rhyncholites and conchorhynchs occur in relatively high abundance and are widely distributed, with a long geological range, extending from the Triassic to the Miocene. While rhyncholites and conchorhynchs are relatively common in Europe, there are only a few reports from North America. Here, we document 24 specimens of rhyncholites and 12 specimens of conchorhynchs from the Upper Cretaceous Mount Laurel Formation in Delaware. The specimens were found in isolation and, thus, identifying the taxon to which the rhyncholites and conchorhynchs belong is difficult. However, the Cretaceous nautilid Eutrephoceras occurs in the same formation, suggesting that the rhyncholites and conchorhynchs may belong to this taxon. We performed a morphometric analysis of these structures based on linear measurements. Our results reveal that some morphological parameters in rhyncholites are correlated with size. Additionally, our specimens exhibit high intraspecific variation, which may have been overlooked in previous studies.
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    Exceptional species diversity of Drosophilidae (Diptera) in a neotropical forest (American Museum novitates, no. 3997)
    (American Museum of Natural History., 2023-05-10) Grimaldi, David A.; Richenbacher, Courtney
    The highest single-site species diversity known thus far in the world for Drosophilidae is in Costa Rica, based on findings in this report. A total of 352 species of Drosophilidae (Diptera) were found in a cloud forest (1580 m) in Zurquí de Moravia, San José Province (hereafter “Zurquí”), based on 2908 specimens collected continuously for one year, using eight trapping and collecting methods. There are currently 305 described species from Costa Rica. Zurquí is at the edge of a large, protected area and was the site of an All-Diptera inventory project. For this study, drosophilid specimens were identified to genus/subgenus, sorted to morphospecies, and their abundances plotted by collection method: Malaise traps, flight intercept traps, baited traps, light and yellow pan traps, emergence traps, and hand collecting with nets. The standard method used by drosophilists, bait trapping, captured a small fraction of species. Malaise traps captured 87% of all species, and 41% of the 352 species were captured only this way. Emergence traps captured a surprising diversity (47 species) of Diathoneura and Drosophila, establishing that leaf litter/humus is an important breeding site for some taxa. Combining all collection methods, 11 species were abundant, as defined by 50 or more specimens, and comprised 35% of all specimens in the study; two-thirds (66%) of all species were rare, as defined by five or fewer specimens. Comparisons are made to other well-collected sites and regions around the world. Lowland to mid-montane forests on the eastern slopes of the Andes may be the most diverse area for Drosophilidae, a family that is exemplary for studying the ecology and evolution of tropical diversity.
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    New fossil giant panda relatives (Ailuropodinae, Ursidae) : a basal lineage of gigantic Mio-Pliocene cursorial carnivores (American Museum novitates, no. 3996)
    (American Museum of Natural History., 2023-03-14) Jiangzhou, Qigao; Flynn, John J. (John Joseph), 1955-; Wang, Shiqi (Paleontologist); Hou, Sukuan; Deng, Tao (Paleontologist)
    Among the fossil members of the giant panda subfamily of ursid carnivorans, Ailuropodinae, one group of species is of giant size, those of Indarctos. Indarctos species have some dental resemblances to and may be closely related to Agriotherium, although there are other clear differences between these taxa, and no known species has definitive shared derived traits that could link these two genera. Here we describe a rich suite of fossil material from both North America and eastern Asia, all belonging to a new genus, Huracan, which possesses characters shared with both Agriotherium and Indarctos but also has diagnostic autapomorphies. The new taxon was distributed widely in the Holarctic during the latest Miocene, including at least four species: the type species Huracan schneideri (previously Agriotherium schneideri) from the latest Hemphillian (Hh4) and possibly early Blancan North American Land Mammal “Ages” (NALMAs), North America; H. coffeyi from the early Late Hemphillian (Hh3) NALMA, North America; H. qiui, sp. nov., from the Baodean Asian Land Mammal “Age” (ALMA), northern China; and H. roblesi from the MN13 zone (latest Miocene–earliest Pliocene) of Spain. Huracan is the nearest sister taxon to Agriotherium, the latter herein considered to be an ailuropodine (in the tribe Agriotheriini) rather than a hemicyonid, and the common ancestor of both genera evolved from Indarctos (with resultant paraphyly of that taxon) or another Indarctos-like ailuropodine bear, likely in eastern Asia. The dentitions of Huracan and Agriotherium both are more specialised for carnivory than most Indarctos species, indicating a radiation of diverse ecological carnivores earlier in the history of the later-diverging, highly specialized herbivores in the giant panda lineage. Their postcranial morphology suggests that species in both genera (Huracan and Agriotherium) were more cursorial than species assigned to Indarctos, and thus well adapted to more open habitats. These derived traits may explain the worldwide replacement of Indarctos species by Huracan and Agriotherium species during the latest Miocene, in response to significant global cooling and expansion of C4 grasslands that occurred at that time.
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    A key to the Pacific genera of Eumeninae (Hymenoptera: Vespidae) (American Museum novitates, no. 3995)
    (American Museum of Natural History., 2023-03-01) Carpenter, James M. (James Michael), 1956-
    A key to the genera of the Eumeninae occurring in Oceania is presented. Hitherto there has been no published key to these genera, making routine identification difficult. New combinations are Pararrhynchium atrum emifasciatum (Giordani Soika), Pararrhynchium simillimum (Giordani Soika), Parodynerus mariannensis (Bequaert and Yasumatsu), and Phimenes solomonis malaitensis (van der Vecht).
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    Revision of the North American Hallodapini (Insecta: Hemiptera: Heteroptera: Miridae: Phylinae) (American Museum novitates, no. 3994)
    (American Museum of Natural History., 2023-02-17) Wyniger, Denise; Schuh, Randall T.; Henry, Thomas J.
    The North American Hallodapini are revised. Cyrtopeltocoris Reuter includes 12 species, five of which (C. brailovskyi, n. sp., C. fractifasciatus, n. sp., C. hallodapoides, n. sp., C. nudipronotum, n. sp., and C. pronotosus, n. sp.) are described as new. Five nominal species of Cyrtopeltocoris and three commingled species of Sericophanes Reuter are placed in synonymy, and a neotype is designated for C. mexicanus Carvalho and Costa. Phoradendrepulus Polhemus and Polhemus, described based on brachypterous males and females, is synonymized under Cyrtopeltocoris, new synonymy, and P. myrmecomorphus Polhemus and Polhemus is synonymized under C. ajo Knight. The new genus Neocyrtopeltocoris, described to include Sericophanes triangularis Knight (with Sericophanes albomaculatus Knight, S. fuscicornis Knight, and S. nevadensis Knight treated as junior synonyms) and N. froeschneri, n. sp., is placed in the Hallodapini. We provide habitus images, illustrations, measurements, and distribution maps for all taxa; genitalic illustrations for most taxa; and a key to the species of Cyrtopeltocoris and Neocyrtopeltocoris to aid in identification.
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    Bundles of sperm : structural diversity in scorpion sperm packages illuminates evolution of insemination in an ancient lineage (American Museum novitates, no. 3993)
    (American Museum of Natural History., 2022-12-13) Vrech, David E.; Peretti, Alfredo V.; Prendini, Lorenzo; Mattoni, Camilo I.
    The spermatozoa of scorpions are often bundled together, forming a type of sperm conjugation known as a sperm package. Sperm packages may be found inside the testes and seminal vesicles but vanish in the female atrium, leaving free spermatozoa. Previous studies, based on a limited number of taxa, suggested a diversity of sperm package morphology across the order Scorpiones C.L. Koch, 1850. However, the sperm packages of most scorpion taxa remained unknown. The present study provides the first systematic survey of sperm package morphology across the order, covering 89 exemplar species in 66 genera and 19 families representing all suprafamilial ranks, with a more detailed investigation of the family Bothriuridae Simon, 1880. Whereas all exemplar species of scorpions exhibit sperm packages, Buthida Soleglad and Fet, 2003, including Chaerilidae Pocock, 1893, and most Buthidae C.L. Koch, 1837, present unorganized sperm or loosely organized bundles. Although the details vary, three main types of sperm packages may be recognized in all other families: single folded; straight; and multiple folded. Subtypes may be identified according to general shape and folding patterns, mainly among sperm packages that are folded multiple times. Single-folded sperm packages are the most common type observed in the order. Although most sperm packages lack a covering, a conspicuous secretion sheath may be evident, e.g., in some Chactidae Pocock, 1893. Sperm packages vary in length from 112–354 μm and bent sperm packages are not necessarily longer than straight sperm packages. Four exemplar species of Bothriuridae reveal that variation in sperm count within a single sperm package is consistent with the count derived in spermatogenesis. The diversity of sperm packages suggests a path from free spermatozoa, via bent sperm packages, to other forms. Sperm packages may aid in the transport, cooperation, competition, and survival of spermatozoa. The diverse morphology, function, and evolution of sperm packages merit further investigation.
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    Systematic review and cranial osteology of Petersius with redescription of P. conserialis (Teleostei: Alestidae) from the Rufiji and Ruvu rivers of Tanzania (American Museum novitates, no. 3992)
    (American Museum of Natural History., 2022-11-15) Melo, Bruno F. 1987-; Stiassny, Melanie L. J.
    We review the systematics of the monotypic alestid genus Petersius and provide a taxonomic redescription of P. conserialis from eastern Tanzania. Morphological investigation includes direct observation and examination of radiographed and μCT-scanned data from type and non-type specimens. We delimit the taxon’s geographic distribution along the lowland regions of the Rufiji and Ruvu river basins in Tanzania and provide information on ecology, sexual dimorphism, and ontogenetic variation. Petersius is herein diagnosed by the possession of a unique cuspidation patterning of the inner-row premaxillary dentition and a distinctively shaped anterodorsal margin of the supraoccipital crest. It shares with some species of Phenacogrammusa sigmoid-shaped process on the dorsal margin of the second infraorbital, a feature lacking in other alestid taxa. Additional features of potential utility for ongoing investigation of relationships among alestid genera include the possession of contralateral premaxillae separated by the anteromedial process of the mesethmoid and without interdigitations connecting the medial surfaces of the premaxillae; four, occasionally five or six, small outer-row premaxillary teeth implanted alternately with those of the inner row; a dentary lacking a pair of conical inner-row teeth proximal to the symphysis; a dorsal posttemporal fossa that is smaller than the ventral fossa; a median third posttemporal fossa located entirely within the epioccipital; a truncate dorsomedial cranial fontanel; and a complete circumorbital series forming an uninterrupted ring around the orbit in adult specimens.
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    A new genus with two new species of Colombian harvestmen (Opiliones: Stygnidae: Stygninae) (American Museum novitates, no. 3991)
    (American Museum of Natural History., 2022-09-16) Villarreal Manzanilla, Osvaldo; Kury, Adriano B.; Colmenares, Pío A.
    Fortia, gen. nov., a new genus of Stygnidae with two new Colombian species, is diagnosed and described. Two possibly sympatric species Fortia jedi, sp. nov., and Fortia sith, sp. nov. (both from the Sierra Nevada de Santa Marta, Magdalena, Colombia), are described and illustrated. Relationships of the new genus are discussed.