Junior Synonym Research Articles

Phylogenetic relationships of Neogene hamsters (Mammalia, Rodentia, Cricetinae) revealed under Bayesian inference and maximum parsimony

There is an ongoing debate about the internal systematics of today’s group of hamsters (Cricetinae), following new insights that are gained based on molecular data. Regarding the closely related fossil cricetids, however, most studies deal with only a limited number of genera and statements about their possible relationships are rare. In this study, 41 fossil species from the Late Miocene to the Pliocene, belonging to seven extinct cricetine genera, Collimys, Rotundomys, Neocricetodon, Pseudocricetus, Cricetulodon, Apocricetus and Hattomys are analysed in a phylogenetic framework using traditional maximum parsimony and Bayesian inference approaches. Following thorough model testing, a relaxed-clock Bayesian inference analysis is performed under tip-dating to estimate divergence times simultaneously. Furthermore, so-called ‘rogue’ taxa are identified and excluded from the final trees to improve the informative value of the shown relationships. Based on these resulting trees, the fit of the topologies to the stratigraphy is assessed and the ancestral states of the characters are reconstructed under a parsimonious approach and stochastic character mapping. The overall topologies resulting from Bayesian and parsimonious approaches are largely congruent to each other and confirm the monophyly of most of the genera. Additionally, synapomorphies can be identified for each of these genera based on the ancestral state reconstructions. Only Cricetulodon turns out to be paraphyletic, while ‘Cricetulodon’ complicidens is a member of Neocricetodon. Lastly, this work makes a contribution to a debate that went on for decades, as the genus Kowalskia can be confirmed as junior synonym of Neocricetodon.

Review of hymenolepidids associated with the tribe Sudarikovinini Spassky, 1991 (Eucestoda, Hymenolepididae), with descriptions of two unrecognized species from the Shaw's jird Meriones (Pallasiomys) shawi (Duvernoy) (Rodentia: Muridae: Gerbillinae) from Northern Africa.

The taxonomic position of the hymenolepidid cestode genera Paraoligorchis Wason et Johnson, 1977 and Sudarikovina Spassky, 1951 from gerbils and ground squirrels from Africa, Southwest Asia and South Asia is clarified based on re-examination of type and voucher materials. The generic diagnosis of Sudarikovina is amended. The main corrections for diagnostic characters at the generic level include: irregularly-spaced transverse anastomoses of ventral osmoregulatory canals; presence of both specimens with dextral genital pores and specimens with sinistral genital pores; vagina clearly covered externally by a dense layer of intensely-stained cells; young uterus reticulate and fully-developed uterus with a labyrinthine structure. The previously proposed generic character of a minimum number of testes per proglottis of species of Sudarikovina is reduced to 3. The genus Paraoligorchis is recognized as a junior synonym of Sudarikovina. For the type species of Paraoligorchis, P. taterae Wason et Johnson, 1977, the replacement name Sudarikovina wasojohni nom. nov. is proposed, thus resolving the secondary homonymy of the transferred species and its senior homonym S. taterae Hunkeler, 1972. The validity of the tribe Sudarikovinini sensu Spassky (1991), to which Paraoligorchis and Sudarikovina had been attributed, cannot be resolved due the lack of molecular data. The cestode specimens from Shaw's jird, Meriones (Pallasiomys) shawi (Duvernoy) from Algeria and Tunisia, initially designated as Hymenolepis sp. by Joyeux (1923) and Hymenolepis procera Janicki, 1904 by Joyeux & Foley (1930), represent undescribed species of Sudarikovina, which are described in this study as Sudarikovina pentatesticulata sp. n. and S. tetratesticulata sp. n., respectively. The main diagnostic characters of the two new species, which distinguish them from their congeners, are the number and the size of the testes.

Two fancy spines and a collar: a taxonomic review of the myrmecomorphic spider genus Mazax O. Pickard-Cambridge, 1898 (Araneae: Corinnidae: Castianeirinae) in South America

The South American species of the myrmecomorphic spider genus Mazax O. Pickard-Cambridge, 1898 (Castianeirinae, Corinnidae) are revised for the first time, increasing the number of known species from South America from two to six and the number of species in the genus from seven to 11. Here, we reevaluate the identity of Apochinomma acanthaspis Simon, 1896, propose its transfer to Mazax, and consider M. akephaloi Perger & Pett, 2022 as a junior synonym of M. acanthaspis comb. nov. Additional documentation of M. ramirezi Rubio & Danişman, 2014 is provided. The species M. pax Reiskind, 1969 and M. spinosa (Simon, 1898) are recorded from South America for the first time. Three new species are proposed, all based on both sexes: Mazax mokana sp. nov. and M. leonidas sp. nov. from Colombia, and M. tembe sp. nov. from Brazil. Emended diagnoses of the genus and of all six known South American species, as well as a key to males and females for all 11 species in the genus, are provided.

A rapid and parallel Late Pleistocene/Holocene morphological radiation in a predaceous planktonic water flea: the case of Bythotrephes (Cladocera: Cercopagididae)

Abstract The predatory cladoceran Bythotrephes is one of North America’s most successful and impactive invasive species in freshwater plankton communities. The taxonomic status of the genus Bythotrephes Leydig, 1860 (Crustacea: Cladocera: Cercopagididae) has remained unclear and a subject of intensive debate for over 150 years. We applied an integrative taxonomy approach with multi-gene analysis (mitochondrial COI and 12S genes, and nuclear 18S and 28S genes) on 80 individuals (representing at least four morphospecies) from various regions spanning the genus distribution (North America, Europe, and Asia) to resolve the taxonomic status of species within Bythotrephes. The results of our study strongly support the hypothesis of a single species—Bythotrephes longimanus Leydig, 1860, and ecological morphs should be accepted as junior synonyms. Our work also elucidates the very recent radiation of Bythotrephes, which may have begun rapidly and parallel during the Late Pleistocene, or even after the last glaciation. Finally, we provide a comprehensive biogeographic reconstruction of Bythotrephes dispersal within the Holarctic realm. Europe likely served as a dispersal centre for Bythotrephes from where they spread relatively recently (possibly, less than 10 kyr) and we distinguish five possible dispersal events in its evolutionary history.

Mitogenomic analysis of the position of the Azygiidae and constituent genera, with a new species of Azygia

The Azygiidae Looss, 1899 is a family of digeneans with a Holarctic distribution in which members of some genera mature in marine elasmobranchs while others occur only in freshwater teleosts. Some have questioned whether the marine genus Otodistomum Stafford, 1904 indeed belongs to the same family as the freshwater azygiid genera, namely Azygia Looss, 1899, Proterometra Horsfall, 1933, and Leuceruthrus Marshall and Gilbert, 1905. We present phylogenetic analyses based on mitochondrial genomes, rDNA operons, and partial Cox1 cytochrome c oxidase I sequences from North American and Asian species that support the monophyly of Azygiidae, and placement of Azygioidea in the suborder Hemiurata, in contrast to recently published mitochondrial genome phylogenies. All phylogenies indicate that Azygia includes Leuceruthrus, which we therefore propose to be a junior synonym, together with suppression of the Leuceruthrinae. The status of Proterometra was equivocal, with support in some but not all analyses of 28S, but not in other markers. We describe a new species of Azygia from northeastern North America. Our results confirm the morphological variability of adults in Azygia, with worm size positively correlated with host size in Azygia angusticauda. Phylogenies suggest a marine origin for the Azygiidae, and a Palearctic origin for freshwater azygiids, with a single trans-Atlantic radiation to the Nearctic.

Revised taxonomy of Synodontis catfishes (Siluriformes: Mochokidae) from the Lake Tanganyika basin reveals lower species diversity than expected

Abstract Synodontis Cuvier, 1816 is a species-rich group of African catfishes. Prior to this analysis, 13 species of Synodontis were recognized from Lake Tanganyika and its tributaries, composing the only extant lacustrine radiation of the genus, with a unique origin of obligate brood parasitism among all fishes. Species differentiation and phylogenetic relationships of this group remained largely unresolved. Herein, the taxonomy of Synodontis in the Lake Tanganyika basin is revised, including redescriptions of all species and an updated identification key. Genetic (mitochondrial and nuclear genomic markers) and morphological data suggest a lower species diversity than previously recognized, supporting the distinction of 10 Synodontis species in the lake basin. Based on our findings, we recognize Synodontis grandiops, Synodontis ilebrevis, and Synodontis lucipinnis as junior synonyms of Synodontis multipunctatus, Synodontis polli, and Synodontis petricola, respectively. No recent material of Synodontis dhonti and Synodontis tanganyicae (with Synodontis lacustricolus as a synonym) was available. Morphometric/meristic data suggest their close relationship to Synodontis granulosus. Sequencing of historical specimens inferred S. tanganyicae as sister to S. granulosus but with a 1.7% divergence based on mitochondrial data. In contrast to previous studies, phylogenomic data support the lacustrine assemblage of Synodontis in Lake Tanganyika as monophyletic.

A new species of larval Caeculisoma (Trombidiformes: Erythraeidae) from Brazil with a key to species

Larvae of Caeculisoma brazilensis Noei & Šundić sp. nov. (Trombidiformes: Erythraeidae) collected from Brazil, is described and illustrated. This is the second species of the genus from Brazil. A key to the larval species of Caeculisoma of the world is presented and the key to world genera of larval Callidosomatinae are amended. We suggest considering Iguatonia seemani Xu & Jin, 2020 as a junior synonym of Dambullaeus jianfengensis Xu & Jin, 2020.

A new species of the Prophaethontidae (Aves, Phaethontiformes) from the early Eocene London Clay

ABSTRACT We report new specimens of the stem group phaethontiform Prophaethon from the early Eocene London Clay of Walton-on-the-Naze (Essex, UK). The two partial skeletons are distinctly smaller than a previously described record of Prophaethon from this locality, which was assigned to P. shrubsolei. Even though some extant aquatic birds show a pronounced sexual dimorphism in size, this is considered unlikely to explain the size disparity of the Prophaethon fossils from Walton-on-the-Naze and the new specimens are here described as P. waltonensis, sp. nov. The distal end of the humerus of the new species differs from that of other Phaethontiformes in the presence of a small but well-defined processus supracondylaris dorsalis. With regard to this feature, it shows a resemblance to the humerus of the Procellariiformes, which is unexpected in light of the recently proposed hypothesis that the sister taxon of the Phaethontiformes are the terrestrial Eurypygiformes. Finally, we comment on prophaethontid remains from the late Paleocene of Kazakhstan, which were assigned to the taxa Zhylgaia Nessov, 1988 and Tshulia Nessov, 1988. We synonymise the latter with the former taxon and also consider it possible that Zhylgaia Nessov, 1988 is a junior synonym of Prophaethon Andrews, 1899.

A review of the types of some Otostigmus (Parotostigmus) (Scolopendromorpha, Scolopendridae, Otostigminae) of the Andes mountain range

Some species of the subgenus Parotostigmus Pocock, 1895 from South America are revised. Previously, 20 species and two subspecies of Parotostigmus were considered to be distributed throughout the Andes from Venezuela to Argentina, but after this study, thirteen species and one subspecies remain valid. Twelve types were examined (O. insignis Kraepelin, 1903, O. muticus Karsch, 1888, O. pococki Kraepelin, 1903, O. silvestrii Kraepelin, 1903, O. lavanus Chamberlin, 1957, O. mesethus Chamberlin, 1957, O. leior Chamberlin, 1955, O. parvior Chamberlin, 1957, O. volcanus Chamberlin, 1955, O. calcanus Chamberlin, 1944, O. amazonae Chamberlin, 1914 and O. bürgeri monsonus Chamberlin, 1957). O. lavanus syn. nov. is a junior synonym of O. insignis; O. parvior syn. nov. is a synonym of O. mesethus; O. amazonae syn. nov. and O. calcanus syn. nov. are synonyms of O. muticus, O. volcanus syn. nov. is a synonym of O. leior; and O. bürgeri monsonus syn. nov. is a synonym of Rhysida celeris (Humbert & Saussure, 1870). A lectotype and a paralectotype are here designated to O. mesethus. Two species, O. scabricauda (Humbert & Saussure, 1870) and O. rex Chamberlin, 1914, previously reported from Colombia, Peru and Brazil, were excluded from the Andean region.

Nadus overlaeti (Navás, 1931) redescribed—new to the fauna of Mozambique, Namibia and Tanzania (Neuroptera: Myrmeleontidae)

Two species used to be included in the African genus Nadus: Nadus overlaeti (Navás, 1931) and Nadus sudanensis Navás, 1935. Following our revision of the genus, we propose that Nadus sudanensis Navás, 1935 (syn.nov.) should be a new junior synonym of Nadus overlaeti (Navás, 1931). The monobasic genus and species are redescribed. Several photographs illustrate morphological features. The distribution, habitat, and seasonal activity of the species are given.

A revision of the Afrotropical hover fly genus Afroxanthandrus Kassebeer, 2000 (Diptera, Syrphidae), with the description of two new species and one new synonymy

The hover fly (Diptera: Syrphidae) genus Afroxanthandrus Kassebeer, 2000 is revised based on morphological and molecular characters. Two new species, Afroxanthandrus comorosensis sp. nov., and Afroxanthandrus conopeum sp. nov. are described, while Xanthandrus magnificus Thompson, 2019 is a new junior synonym of Afroxanthandrus congensis (Curran, 1938). We also redescribe A. congensis stat. rev. and A. longipilus stat. rev. and report additional distribution records for both species.

Black flies (Diptera: Simuliidae) in the Galapagos Islands: Native or adventive?

Invasive species are a threat to ecosystems worldwide, but determining if a species is adventive or native is not always straightforward. The black flies that inhabit the Galapagos Islands, long known as Simulium ochraceum, are blood-feeding pests of humans and livestock. They first came to the attention of residents in 1989, suggesting a recent arrival. Earlier colonization, however, has been suggested, based largely on polymorphic genetic loci. To address questions of origin, provenance, and length of residency, we conducted a macrogenomic analysis of the polytene chromosomes of the S. ochraceum complex from seven sites in the Galapagos Islands and 30 sites in mainland Ecuador, Central America, and the Caribbean. Among 500 analyzed larvae, we discovered 88 chromosomal rearrangements representing 13 cytoforms, at least seven of which are probably full species. All evidence points to a single, cohesive cytoform with full species status in the Galapagos, conspecific with mainland populations, and widely distributed in the Neotropical Region. It has an identical, nearly monomorphic banding sequence with 10 novel fixed inversions and a subtle but unique Y-linked chromosomal rearrangement across all populations sampled in the Galapagos, the mainland, and the Caribbean. We recalled the name Simulium antillarum from synonymy with S. ochraceum and applied it to the Galapagos black flies, and we established that wolcotti is a junior synonym of antillarum. The time(s) and mode(s) of arrival of S. antillarum in the Galapagos remain uncertain, although the wide geographic distribution, including islands in the Caribbean, suggests that the species is an adept colonizer. Regardless of how long it has been in the archipelago, S. antillarum might have assumed a functional role in the streams of San Cristobal, but otherwise has had a detrimental effect on humans and livestock and potentially on the unique birds and mammals of the Galapagos Islands.

A revision of recent taxonomic changes to the eyelash palm pitviper, Bothriechis schlegelii (Serpentes, Viperidae)

The taxonomy of the Bothriechis schlegelii species group has recently been expanded, nearly doubling the number of recognized species within this genus. However, the validity of these new species, defined primarily by mitochondrial DNA and without a robust evaluation of nuclear DNA and morphological data, warrants critical reassessment. This study re-examines the integrative data used in the initial analysis and employs additional visualizations of the genetic and morphological datasets. The results suggest that the genetic differences previously interpreted as species boundaries may instead reflect clinal variation, not independent lineages. Furthermore, DELINEATE species delimitation analysis and morphological assessments challenge the distinction of the proposed taxa. The findings indicate that only three species in the B. schlegelii group should be maintained as valid (B. nigroadspersus, B. schlegelii, and B. supraciliaris), while most taxa proposed by Arteaga et al. (2024) should be considered junior synonyms, or at most, as subspecies. This has significant implications for conservation priorities and resource allocation. In highlighting the need for a cautious and thorough approach to species delimitation, this study contributes to the broader discussion of taxonomic practices, the issue of taxonomic inflation, and their impact on biodiversity conservation.

On new genera and species of crack-leg spiders (Araneae, Udubidae) from Madagascar

Two new genera, Tabiboka gen. nov. and Zorascar gen. nov., are described to accommodate five new Udubidae species from Madagascar: Tabiboka milleri gen. et sp. nov. (type species; ♂♀), T. milloti gen. et sp. nov. (♂♀), T. polotowae gen. et sp. nov. (♂♀), Zorascar pasunepipe gen. et sp. nov. (type species; ♂♀) and Z. pasunepomme gen. et sp. nov. (♀). In addition, two new species of Zorodictyna Strand, 1907 are described: Zorodictyna almae sp. nov. (♂♀) and Z. silvadavilae sp. nov. (♂♀). Uduba inhonesta Simon, 1906 is declared to be a junior synonym of Zorodictyna oswaldi (Lenz, 1891). The descriptions of the new species are complemented with a phylogenetic analysis to tentatively place them into an existing phylogenetic framework. Phylogenetic analyses based on COI and 16S rRNA genes and morphological data show that they are separate species and confirm their familial and supraspecific placement within the Udubidae. The new species are further described using high quality colored photographs, drawings, SEM and (for Zorascar gen. nov. ssp.) by the use of X-Ray micro-computed tomography to recreate virtual 3D models without destroying the original specimens. A dichotomous key to identify Malagasy Ububidae is provided. Whereas many undescribed Udubidae remain in Madagascar, the phylogenetic and generic arrangement that we present here succinctly summarizes the higher classification of Madagascar Udubidae.

Taxonomic notes on Prothemus Champion (Coleoptera: Cantharidae), with descriptions of two new species from China and Vietnam

Prothemus longiphysus Wittmer, 1995 is considered as a junior synonym of P. sanguinosus (Farimaire, 1900). Meanwhile, P. angustioripennis (Pic, 1927), originally described in Cantharis, is removed from the synonym of P. sanguinosus and reinstated as a valid species. Besides, two new species are discovered and described under the names of P. biprominens sp. nov. and P. venustiformis sp. nov. In addition, the macrophotographs of aedeagi and female internal genitalia are firstly provided for the following species: P. sanguinosus, P. purpureipennis (Gorham, 1889), P. chinensis Wittmer, 1987, P. kiukianganus (Gorham, 1889), P. limbolarius (Fairmaire, 1900) and P. monochrous (Fairmaire, 1900). A key to the Prothemus species from Nanling National Natural Reserve, China is provided.

Recent non-marine ostracods (Crustacea) from New Caledonia (Melanesia, Pacific Ocean)

The New Caledonian Archipelago is a hot spot for biodiversity and endemism. Here, we report on new records of nine species from localities on the main island, Grande Terre, and illustrate these: Ilyodromus viridulus (Brady, 1886), Stenocypris hislopi Ferguson, 1969, S. macedonica Petkovski & Meisch, 1996¸ S. malayica Victor & Fernando, 1981, Bradleytriebella lineata (Victor & Fernando, 1981), Hemicypris pyxidata (Moniez, 1892), Heterocypris incongruens (Ramdohr, 1808), Cypridopis vidua (O.F. Müller, 1776) and Limnocythere stationis Vávra, 1891. We also provide redescriptions and illustrations of the valves and carapace of Stenocypris marginata Daday, 1910 sensu Méhes, 1939, Cypris granulata Daday, 1898 and Kennethia major (Méhes, 1939); for the latter species also including some soft parts. Therefore, twenty two certain species have thus far been reported from the New Caledonian Archipelago. The status of seven uncertain species is also discussed. Previous records of Stenocypris major (Baird, 1859) from Grande Terre, mainly by Méhes, are here considered to belong to S. hislopi. We propose to reject the presence of Cyprinotus cingalensis Brady, 1886 in New Caledonia and suggest to consider Cypridopsis sarasini Méhes, 1939 as an “uncertain species” (sensu Meisch et al. 2019). We also argue that Eucypris wolffhuegeli Méhes, 1914 might be a synonym of H. incongruens and suggest that Strandesia rouxi Méhes, 1939 might be considered a junior synonym of an existing species, pending further research.

Revision of the nomenclature status and taxonomic implications of two Lepidion species (Gadiformes: Moridae)

Lepidion lepidion and Lepidion eques are two nominal species of the genus Lepidion (Moridae) from the Mediterranean Sea and the North Atlantic Ocean, respectively. Following the publication of the latter species, several authors highlighted the morphological similarities between them, questioning their taxonomic relationship. Despite these reasonable doubts, the two species have long been considered as valid and separate species. Since the 2010s, a series of integrative studies, combining morphological and molecular analyses, have demonstrated that L. eques is a junior synonym of L. lepidion. However, the former has continued to be used inconsistently in biodiversity databases and ichthyological literature. Thus, while the “Catalog of fishes” immediately incorporated this new status, the databases “FishBase” and “WoRMS” did not, maintaining the validity of both species. Consequently, in the scientific literature, only a few authors adhere to the synonymy relationship, naming the Atlantic species as L. lepidion, while most maintain the older nomenclature of L. eques. These two nominal species represent an interesting case study on the application of taxonomic nomenclature and how the different criteria for incorporating new species affect the scientific community.

Synonymic notes in the Southeast Asian genus Lutera Westwood, 1875 (Coleoptera: Scarabaeidae: Rutelinae)

To resolve the taxonomic confusion surrounding two Asian Rutelinae species, Lutera nigromaculata Ohaus, 1900 and L. nigrita Ohaus, 1930, all primary types of relevant taxa have been revisited. A redescription of L. nigromaculata is given, and diagnosis and color illustrations are provided for both L. nigromaculata and L. nigrita. Parastasia ohausi Chûjô, 1966 (new synonym), an unnecessary replacement name for and junior objective synonym of L. nigromaculata, was found in a neglected publication by the late Michio Chûjô. A lectotype is designated for L. nigromaculata guttata (Frey, 1970) (new synonym) which is recognized as another junior synonym of L. nigromaculata. All known distribution records of the two species are mapped, and L. nigromaculata is newly recorded from India and Vietnam. The exact location of “Lakhon” in Indo-China, which is currently Nakhon Phanom of Thailand, is also discussed.

The genus Argopistes Motschulsky from Japan and Taiwan, with descriptions of three new species from Taiwan (Coleoptera, Chrysomelidae, Galerucinae, Alticini).

Four previously described species of Argopistes are recognized and redescribed from Japan and Taiwan: A.biplagiatus Motschulsky, 1860, A.rufus Chen, 1934, A.tsekooni Chen, 1934, and A.unicolor Jacoby, 1885. Three new species from Taiwan, A.jungchani sp. nov., A.tsoui sp. nov., and A.yuae sp. nov., are described. Descriptions of species include illustrations of aedeagi, antennae, gonocoxae, abdominal ventrite VIII, and spermathecae. Argopistesrufus Chen, 1934, stat. nov. is raised to species status from a variety of A.biplagiatus Motschulsky, 1860. Argopistescoccinelliformis Csiki, 1940, syn. nov. and A.ryukyuensis Shigetoh & Suenaga, 2022, syn. nov. are proposed as junior synonyms of A.rufus Chen, 1934 Lectotypes are designated for A.undecimmaculata Jacoby, 1885, A.unicolor Jacoby, 1885, and A.biplagiatusvar.rufus Chen, 1934.

Revision of the Chinese termite genus Peribulbitermes (Blattodea, Isoptera, Termitidae): A new synonym of Ahmaditermes

The genus Peribulbitermes is a small genus in Nasutitermitinae comprising three species distributed only in China. Type specimens of Peribulbitermes dinghuensis Li, 1985 and Peribulbitermes jinghongensis Li, 1985 are obtained in our study. After examining the morphological characters of the specimens, it is found that P. jinghongensis cannot be differentiated from P. dinghuensis by the diagnostic characters reported in original description. We propose that P. jinghongensis is the junior synonym of P. dinghuensis. Additionally, molecular phylogenetic relationships of Peribulbitermes, with its morphologically similar genera, Bulbitermes, Ahmaditermes and Nasutitermes, as well as other nine genera in Nasutitermes Group of Nasutitermitinae were analysed based on mitochondrial COI, COII and 16S rRNA genes. The results show that the relationship between Peribulbitermes and Ahmaditermes is the closest. Peribulbitermes should be downgraded to synonymy of Ahmaditermes. P. dinghuensis and Peribulbitermes parafulvus (Tsai and Chen, 1963) should be transferred to Ahmaditermes as Ahmaditermes dinghuensis and Ahmaditermes parafulvus.