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Wednesday, July 20th, 2022
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| 9:18a | [Ichthyology • 2022] Astronotus mikoljii • A New Species of Astronotus (Teleostei: Cichlidae) from the Orinoco River and Gulf of Paria Basins, northern South America
Abstract Based on morphological and molecular analysis of Astronotus species, a new species is described from the Orinoco River and Gulf of Paria basins in Venezuela and Colombia. Morphologically, it differs from Astronotus crassipinnis and Astronotus ocellatus in pre-orbital depth, caudal peduncle depth, head width, and caudal peduncle length, with significant differences in average percentage values. Osteologically, it differs from the two described species by lacking a hypurapophysis on the parahypural bone (hypural complex) and having two or three supraneural bones. Another characteristic that helps diagnose the new species is the morphology of the sagitta otolith, which is oval with crenulated dorsal and ventral margins and a rounded posterior edge. Genetically, the new species is distinct from all the other lineages previously proposed for the genus, delimited by five single locus species delimitation methods, and also has unique diagnostic nucleotides. Phylogenetic analyses support the monophyly of the new species as well as all other species/lineages. Astronotus species have considerable genetic, anatomical, and sagitta otolith shape differences, but have few significant traditional morphometric and meristic differences, because there is high variability in counts of spines, soft dorsal-fin rays, and lateral-line scales. It is clear that this new species is genetically and anatomically differentiated from all other species within the genus, and deserves recognition as a new valid species. Keywords: DNA, fish, freshwater, morphometrics, osteology, sagitta otoliths, taxonomy
Astronotus mikoljii sp. nov. Diagnosis: The new species is distinguished from congeners by the following combination of characters: two or three supraneural bones (Fig. 4) (vs. two); absence of the spinous process (hypurapophysis) on the anterosuperior border of the parahypural bone (hypural complex) in Astronotus mikoljii sp. nov. (vs. present in A. ocellatus and A. crassipinnis) (Fig. 5). The sagitta otolith in A. mikoljii sp. nov. is oval, with strongly crenulated ventral and dorsal margins (vs. elliptical and smooth-lobed margins in A. crassipinnis, and elliptical and smooth-dentate margins A. ocellatus); the rostrum is projected with an elongated process, in A. mikoljii sp. nov. (vs. rostrum process short in A. crassipinnis and A. ocellatus); the posterior region of the sagitta otolith is rounded in A. mikoljii sp. nov. (vs. straight or flat in A. crassipinnis and A. ocellatus) (Fig. 6). The aspect ratio of sagitta otoliths in A. mikoljii sp. nov. (AR = 0.665) is higher than that of A. ocellatus (AR = 0.606), and A. crassipinnis (AR = 0.585), and the differences are statistically significant at P < 0.05. The roundness index was highest in A. mikoljii sp. nov. (Rd = 0.597) vs. A. ocellatus (Rd = 0.545) and A. crassipinnis (Rd = 0.543) (P < 0.05). Also the morphometric index showed higher values in A. mikoljii sp. nov. compared to A. ocellatus (0.837 vs. 0.767) and A. crassipinnis (0.735) (Suppl. material 1: Table S2). The new species also is distinguished from congeners by the following combination of morphometric characters: the mean head length of A. mikoljii sp. nov. (36.72% SL) is longer than that of A. crassipinnis (35.01% SL), and also A. ocellatus (33.26% SL); the mean diameter of the orbit of A. mikoljii sp. nov. (9.06% SL) is greater than that of A. ocellatus (7.36%SL) and that of A. crassipinnis (7.73% SL); the mean pre-orbital depth of A. mikoljii sp. nov. (14.22% SL) is greater than that of A. crassipinnis (10.14% SL) but less than that of A. ocellatus (15.91% SL); the mean snout length of A. mikoljii sp. nov. (11.53% SL) is longer than that of A. crassipinnis (5.36% SL), and A. ocellatus (10.67% SL) (Tables 1, 2).  Etymology: The specific name is given to honor Mr. Ivan Mikolji, Venezuelan explorer, artist, author, underwater photographer, and audiovisual producer, in recognition for being a tireless and enthusiastic diffuser of the biodiversity and natural history of freshwater fishes, conservation of aquatic ecosystems of Venezuela and Colombia, and for logistic support for this work. Since 2020, Ivan Mikolji has been recognized as Associate Researcher of the Museo de Historia Natural La Salle, from the Fundación La Salle de Ciencias Naturales, in Caracas, Venezuela. Common names: In Spanish and indigenous local languages, names which are known for Astronotus mikoljii sp. nov. in Venezuela are pavona, vieja, cupaneca, Oscar, mijsho (Kariña), boisikuajaba (Warao), hácho (Pumé = Yaruro), phadeewa, jadaewa (Ye’Kuana = Makiritare), perewa, parawa (Eñepá = Panare), yawirra (Kúrrim = Kurripako), kohukohurimï, kohokohorimï, owënawë kohoromï” (Yanomami = Yanomamï) (Barandiarán 1962; Mago 1967, 1970c; Novoa et al. 1982; Obregón et al. 1984; Román 1985; Novoa 1986; Román 1988; Bedoya 1992; Mattei-Müller et al. 1994; Lasso and Machado-Allison 2000; Mosonyi 2002; Machado-Allison 2003; Vispo and Knab-Vispo 2003; Mattei-Müller and Serowe 2007; Brito et al. 2011) and pavo real, carabazú, Oscar, mojarra, mojarra negra, eba (Puinave), Itapukunda (Kurripako), uan (Tucano) in Colombia (Sánchez 2008). The suggested common name for this species in the aquarium hobby is “Mikolji’s Oscar” in English, “Oscar de Mikolji ‘’ in Spanish.  Alfredo Perez Lozano, Oscar M. Lasso-Alcalá, Pedro S. Bittencourt, Donald C. Taphorn, Nayibe Perez and Izeni Pires Farias. 2022. A New Species of Astronotus (Teleostei, Cichlidae) from the Orinoco River and Gulf of Paria Basins, northern South America. ZooKeys. 1113: 111-152. DOI: 10.3897/zookeys.1113.81240  | ||||||||
| 11:15a | [Herpetology • 2022] Desmognathus gvnigeusgwotli, D. kanawha & D. mavrokoilius • Nomenclatural Solutions for Diagnosing ‘Cryptic’ Species using Molecular and Morphological Data facilitate A Taxonomic Revision of the Black-bellied Salamanders (Urodela: Pl
Abstract To be available under the International Code of Zoological Nomenclature, nomina erected after 1930 must “be accompanied by a description or definition that states in words characters that are purported to differentiate the taxon” (Article 13.1.1). For many so-called ‘cryptic’ species, this may prove difficult when relying on external morphology. Yet, such species are likely to be diagnosable by (fixed or variable) differences in DNA sequences, which can also be treated as characters and described in words. While recent authors have proposed such methods, they have rarely been adopted as the primary diagnostic implement in vertebrates. Additionally, morphometrics may reveal subtle but distinct variation in size and shape, which may not be dispositive for identifying individual specimens but can nonetheless characterize overall differences between species. We employ these techniques here to revise the taxonomy of the Black-bellied Salamanders Desmognathus folkertsi and Desmognathus ‘quadramaculatus’ from the southern Appalachian Mountains of the eastern United States. While the former was diagnosed by a variety of morphological and molecular characters, the latter was poorly characterized and subsequently found to consist of two distantly related clades of six genetic lineages. Recent nomenclatural work found that the nomen Salamandra quadramaculata Holbrook, 1840 was unavailable for this species and that no valid nomen had ever been applied at the species level. We erect three new species and resurrect one junior synonym to account for species-level geographic genetic variation in the group. All nomina are diagnosed with explicit reference to fixed or varying allelic differences at mitochondrial and nuclear loci, quantitative variation in overall size and shape from linear morphometrics, and qualitative description of color-pattern variation. Despite their gross similarity, we hypothesize that subtle, as-yet undetected phenotypic variation exists between these species, which may be revealed by geometric morphometrics, 3D scanning, and other data such as physiology and behavior. We also utilize recently developed technologies to present DNA-sequence data for these species in a compact, reproducible format to permanently associate the observed characters with the original description, with several thousand base pairs taking up only a few cm2. These approaches may prove useful for future descriptions of amphibians with highly similar external phenotypes. Keywords: validity, molecular characters, availability, convergence, phenotype, Amphibia
 R. Alexander Pyron and David A. Beamer. 2022. Nomenclatural Solutions for Diagnosing ‘Cryptic’ Species using Molecular and Morphological Data facilitate A Taxonomic Revision of the Black-bellied Salamanders (Urodela, Desmognathus ‘quadramaculatus’) from the southern Appalachian Mountains. Bionomina. 27(1); 1-43. DOI: 10.11646/bionomina.27.1.1  | ||||||||
| 2:48p | [PaleoOrnithology • 2022] Cryptogyps lacertosus • A New Look at An Old Australian Raptor places “Taphaetus” lacertosus de Vis 1905 in the Old World vultures (Accipitridae: Aegypiinae)
Abstract The Australian Pleistocene fossil record of the Accipitridae (hawks, eagles and Old World vultures) is sparse and poorly known. Only two extinct confirmed accipitrid species have been described for this time period; both have received little investigation since their description. One is “Taphaetus” lacertosus de Vis, 1905, described from a distal humerus and a quadrate from north-eastern South Australia. While this species was verified as an accipitrid in subsequent studies, its more precise taxonomic affinities have remained conjectural. In this study, a new analysis incorporating newly referred material and phylogenetic analyses using a wide range of accipitriforms reveals that the lectotype humerus of “T.” lacertosus is an Old World vulture in the subfamily Aegypiinae. The associated quadrate, one of two original syntypes from which de Vis named this species, is of an indeterminate species of ardeid. We erect the novel genus Cryptogyps, to accommodate the species ‘lacertosus’, as it cannot be placed in Taphaetus de Vis, 1891, because the type species of this genus, Uroaetus brachialis de Vis, 1889, was transferred back to the genus Uroaetus, a synonym of Aquila Brisson, by de Vis in 1905. Further, U. brachialis is now considered a synonym of Aquila audax (Latham, 1801). Moreover, Taphaetus de Vis, 1891 is a senior homonym of Taphaetus de Vis, 1905, type species Taphaetus lacertosus de Vis, 1905, making the 1905 version of the genus unavailable. Newly referred fossils from Wellington Caves (NSW) and the Nullarbor Plains (WA) reveal this taxon had a wide geographical range across Pleistocene Australia. The referred tarsometatarsus lacks hyper-developed trochleae, indicating that Cryptogyps lacertosus (de Vis, 1905) comb. nov., was probably a scavenger like other aegypiines. Identification of Cryptogyps lacertosus as an aegypiine significantly expands the palaeogeographical range of the Old World vultures, hitherto unknown in Australia. The avian guild of large, obligate scavenging birds of prey, is currently absent in the modern Australian biota, but its former presence is not surprising given the megafauna-rich communities of the Pleistocene. Key words: Pleistocene fossil birds, Accipitriformes, extinction, scavengers, biogeography, Australia --novataxa_2022-Mather_Lee_et_Worthy__@Ellenaetus.jpg) --novataxa_2022-Mather_Lee_et_Worthy__@Ellenaetus.jpg) Cryptogyps Mather, Lee and Worthy 2022 gen. nov. Type species: ‘Taphaetus’ lacertosus de Vis, 1905: Annals of the Queensland Museum 6: 4, pl. 1, fig. 1. Etymology: The name is derived from a combination of the Ancient Greek words ‘kryptós’ (hidden) and ‘gýps’ (vulture), in reference to the fact that this taxon was known for over 100 years but was generally believed to be an eagle. Cryptogyps also relates to the word ‘crypt’, a word used to describe an underground burial chamber, referencing the discovery of the new material in caves. Conclusion: “Taphaetus” lacertosus de Vis, 1905, is confirmed to be a valid species of extinct accipitrid, for which the new genus Cryptogyps is erected. Cryptogyps lacertosus (de Vis, 1905) is shown to be an aegypiine vulture that was widespread in southern Australia in the middle to late Pleistocene. The presence of Old World vultures (Aegypiinae) among Pleistocene Australian accipitrids indicates that their taxonomic and ecological diversity was significantly greater then than it is today; the extinction of Cryptogyps lacertosus likely had a distinct impact on those ancient ecosystems. --novataxa_2022-Mather_Lee_et_Worthy__@Ellenaetus.jpg) Ellen K. Mather, Michael S. Y. Lee and Trevor H. Worthy. 2022. A New Look at An Old Australian Raptor places “Taphaetus” lacertosus de Vis 1905 in the Old World vultures (Accipitridae: Aegypiinae). Zootaxa. 5168(1); 1-23. DOI: 10.11646/zootaxa.5168.1.1 --novataxa_2022-Mather_Lee_et_Worthy__@Ellenaetus.jpg) --novataxa_2022-Mather_Lee_et_Worthy__@Ellenaetus.jpg) |
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