Mitogenomics of Vetigastropoda: insights into the evolution of pallial symmetry

The nucleotide sequences of the complete or nearly complete mitochondrial (mt) genomes of seven vetigastropods were determined: Angaria neglecta (Angarioidea), Phasianella solida (Phasianelloidea), Granata lyrata (Seguenzioidea), Tegula lividomaculata and Bolma rugosa (Trochoidea), Diodora graeca (Fissurelloidea) and Lepetodrilus schrolli (Lepetodriloidea). While the mt genomes of the superfamilies Angarioidea, Phasianelloidea, Seguenzioidea and Trochoidea conform generally to the ancestral gene order of Vetigastropoda and Gastropoda, those of the superfamilies Fissurelloidea and Lepetodriloidea have suffered important rearrangements. The gene order of the mtDNA of Chrysomallon squamiferum, a representative of Neomphalina, was also analysed since it has been proposed to be closely related to Vetigastropoda, and showed a distinct arrangement. The reconstructed phylogenies recovered Neomphalina as a distinct gastropod lineage that is the sister group (only with moderate bootstrap support) of a clade including Vetigastropoda and Neritimorpha + Caeno‐gastropoda while the relative position of Heterobranchia and Patellogastropoda in the gastropod tree could not be determined definitively due to their long branches. Within the monophyletic Vetigastropoda, the superfamily Fissurelloidea was recovered as the sister group of two lineages, one including Lepetodriloidea as the sister group of Seguenzioidea + Halitoidea, the other including Phasianelloidea, Angarioidea and Trochoidea without resolved relationships. The long branches of Fissurelloidea were found to introduce significant tree instability in phylogenetic reconstruction. The new phylogeny supports that the loss of the right pallial gill occurred multiple times in vetigastropod evolution as previously suggested and that Phasianelloidea, Angarioidea and Trochoidea radiated from a common asymmetric (single‐gilled) ancestor that lived in the middle Palaeozoic.     

Phylogenetic relationships among six vetigastropod subgroups (Mollusca, Gastropoda) based on 18S rDNA sequences

Complete 18S rDNA sequences were determined for 10 vetigastropods in order to investigate the phylogeny of Vetigastropoda, which is controversial. These sequences were analyzed together with published sequences for nine other vetigastropods and two nerites. With the two nerites as outgroups, the phylogeny was inferred by three analytical methods, neighbor-joining, maximum likelihood, and maximum parsimony. The 18S rDNA sequence data support the monophyly of four vetigastropod superfamilies, the Pleurotomarioidea, the Fissurelloidea, the Haliotoidea, and the Trochoidea. The present results yield the new branching order: (Pleurotomarioidea (Fissurelloidea ((Scissurelloidea, Lepetodriloidea) (Haliotoidea, Trochoidea)))) within the vetigastropod clade.     

A Molecular Phylogenetic Investigation of Bakuella,Anteholosticha, and Caudiholosticha (Protista,Ciliophora, Hypotrichia) Based on Three‐Gene Sequences

Traditionally classifications of the Urostyloida have been mainly based on morphology and morphogenesis. Recent molecular phylogenetic analyses have been largely based on single‐gene data for a limited number of taxa. Consequently, incongruence has arisen between the morphological/morphogenetic and the molecular data. In this study, the three phylogenetic markers (SSU rDNA, ITS1‐5.8S‐ITS2 region, and LSU‐rDNA) of three urostyloid genera represented by four species (Bakuella granulifera, Anteholosticha monilata, Caudiholosticha sylvatica, and C. tetracirra) were sequenced to investigate their phylogeny. The results show that: (1) all three genera should be regarded as the members of the order Urostyloida within the subclass Hypotrichia, as indicated by morphological characters; (2) phylogenetic analyses and sequence similarities both indicate that neither Anteholosticha nor Caudiholosticha are monophyletic and the systematic assignment of both genera awaits further evaluation; and (3) Bakuella has a closer relationship with Urostyla than with bakuellids (e.g. Apobakuella and Metaurostylopsis), suggesting Bakuella may belong to the family Urostylidae rather than the family Bakuellidae.     

THE FINE STRUCTURE OF THE CTENIDIAL SENSE ORGANS (BURSICLES) OF VETIGASTROPODA (ZEUGOBRANCHIA, TROCHOIDEA) AND THEIR FUNCTIONAL AND PHYLOGENETIC SIGNIFICANCE

The fine-structure of the bursicles of members of all threesubgroups of Vetigastropoda (Fissurelloidea, Pleurotomarioidea,Trochoidea) is described. Specific sensory elements (paddlecilia) suggest a chemo-sensory function of the sense organs.This agrees with earlier physiological results which demonstratedthe role of bursicles in detecting predatory sea-stars. Similarpockets in the (secondary) gill-leaflets of the Pseudococculinidae,are not homologous with the bursicles. The lack of bursiclesin group-B hot-vent limpets and in Neomphalus excludes thesegroups from the Vetigastropoda. The bursicles are regarded asa synapomorphic character of the vetigastropod groups provingtheir evolutionary unity. (Received 13 June 1986;     

Systematic revision of Entomobryidae (Collembola) by integrating molecular and new morphological evidence

Entomobryidae, the largest collembolan family, is traditionally classified at suprageneric level using a limited set of morphological structures, such as scales, antennal segmentation. Most tribal and subfamilial delimitations appear, however, disputable in the light of recent works. Integrating molecular and morphological evidence, we propose here a revision of the systematics of the family. In addition to traditional taxonomic characters, tergal specialized chaetae (S‐chaetae) are newly introduced, and their patterns are shown to be diversified at all levels from species to subfamilies. S‐chaetotaxic pattern on phylogenetic tree shows that evolution of S‐chaetae is not parallel between the different terga and that their patterns coincide well with the known molecular phylogeny, providing a powerful tool for the systematics of Entomobryidae. Orchesellinae sensu Soto‐Adames et al. (Annals of the Entomological Society of America, 101, 2008, 501); is divided into three subfamilies: Orchesellinae s. s., Bessoniellinae and Heteromurinae, the latter two upgraded from the original tribal level. Entomobryinae sensu Szeptycki (Morpho‐Systematic Studies on Collembola. IV. Chaetotaxy of the Entomobryidae and its Phylogenetical Significance, 1979), is no longer divided into scaled and unscaled tribes, and Lepidosira‐group is transferred from Seirinae to Entomobryinae. A key to subfamilies and tribes and a comparison with previous classifications of the Entomobryidae are provided. This study greatly improves the understanding of primary and secondary characters and erects the fundamental framework for the taxonomy of Entomobryidae.     

Endoscopy of gastropods: A novel view of the mantle cavities and gills of the keyhole limpet Diodora aspera and the abalone Haliotis rufescens

The gills, or ctenidia, of marine gastropods serve as the sites for respiratory gas exchange. Cilia on the surface provide the pump that moves water through the mantle cavity and enhance diffusion. Because the gills are housed inside the shell, it is difficult to view them while they are functioning. Published images of gills show contracted, fragile structures that are distorted by the processes of dissection and preservation. Members of the families Fissurellidae (keyhole limpets) and Haliotidae (abalone) have openings in their shells through which water enters and/or exits. I inserted an endoscope connected to a video camera into the openings of the shells of living, non‐anaesthetized individuals of the fissurellid Diodora aspera and the haliotid Haliotis rufescens. In both species, the dorsal afferent branchial vessel of the afferent gill axis appeared large and inflated, as did the leaflets that extended from either side of the axis. In D. aspera, the leaflets appeared to fill the mantle cavity and responded to touch, particles, and dye in the water by contracting quickly and slowly re‐extending. In contrast, the gills of H. rufescens did not noticeably respond to disturbance. On the other hand, these gills showed a regular pattern of pleats that had not been described in the extensive anatomical literature of these common and economically significant animals. These results provide a novel view of the gastropod mantle cavity as a dynamic space filled by the gills, which divide the mantle cavity into distinct incurrent and excurrent chambers and produce a laminar flow of water through the cavity. J. Morphol. 276:787–796, 2015. © 2015 Wiley Periodicals, Inc.     

Phylogeny and reclassification of the Caucasigenini radiation from the Caucasus region (Gastropoda,Hygromiidae)

The Caucasigenini is an endemic radiation of hygromiid land snails from the Caucasus region. A phylogenetic analysis of morphological characters of the genitalia and the shell showed that the morphological characters are insufficient for resolving the relationships within the Caucasigenini. Convergences of the few parsimony informative characters in other groups of the Hygromiidae demonstrate that these characters are not reliable indicators of phylogenetic relationships. Phylogenetic analyses of sequences of cox1, 16S rDNA, 5.8S rDNA, ITS2 and 28S rDNA revealed several well‐supported groups. The relationships among these groups could not be resolved. It is likely that these groups originated in a rapid radiation during the uplift of the Caucasus. Based on the molecular phylogeny, we propose a new classification of the species of the Caucasigenini and establish a new genus, Lazicana gen. n.     

Molecular phylogeny and systematics of Dipodoidea: a test of morphology‐based hypotheses

Lebedev, V.S., Bannikova, A.A., Pagès, M., Pisano, J., Michaux, J.R. & Shenbrot, G.I. (2012). Molecular phylogeny and systematics of Dipodoidea: a test of morphology‐based hypotheses. —Zoologica Scripta, 42, 231–249. The superfamily Dipodoidea (Rodentia, Myomorpha) in its current interpretation contains a single family subdivided into six subfamilies. Four of them include morphologically specialized bipedal arid‐dwelling jerboas (Dipodinae – three‐toed jerboas, Allactaginae – five‐toed jerboas, Cardiocraniinae – pygmy jerboas and Euchoreutinae – long‐eared jerboas), the other two are represented by more generalized quadrupedal taxa (Zapodinae – jumping mice and Sminthinae – birch mice). Despite considerable effort from morphologists, the taxonomy as well as the phylogeny of the Dipodoidea remains controversial. Strikingly, molecular approach has never been envisaged to investigate these questions. In this study, the phylogenetic relationships among the main dipodoid lineages were reconstructed for the first time using DNA sequence data from four nuclear genes (IRBP, GHR, BRCA1, RAG1). No evidence of conflict among genes was revealed. The same robustly supported tree topology was inferred from the concatenated alignment whatever the phylogenetic methods used (maximum parsimony, maximum‐likelihood and Bayesian phylogenetic methods). Sminthinae branches basally within the dipodoids followed by Zapodinae. Monophyletic Cardiocraniinae is sister to all other jerboas. Within the latter, the monophyly of both Dipodinae and Allactaginae is highly supported. The relationships between Dipodinae, Allactaginae and Euchoreutinae should be regarded as unresolved trichotomy. Morphological hypotheses were confronted to findings based on the presented molecular data. As a result, previously proposed sister group relationships between Euchoreutes and Sicista, Paradipus and Cardiocraniinae as well as the monophyly of Cardiocaniinae + Dipodinae were rejected. However, the latter association is consistently supported by most morphological analyses. The basis of the obvious conflict between genes and morphology remains unclear. Suggested modifications to the taxonomy of Dipodoidea imply recognition of three families: Sminthidae, Zapodidae and Dipodidae, the latter including Cardiocraniinae, Euchoreutinae, Allactaginae and Dipodinae as subfamilies.     

The higher‐level phylogenetic relationships of the Eumeninae (Insecta,Hymenoptera, Vespidae), with emphasis on Eumenes sensu lato

Cladistic analyses were carried out to infer the phylogenetic relationships among taxa that were originally part of the large genus Eumenes. Terminals belonging to other eumenine lineages were also included, as well as terminals from other vespid subfamilies. Analyses under equal weights and implied weights were carried out, and better results were obtained with the latter. The results corroborated the monophyly of Eumeninae, and recovered Zethini sensu lato as the sister‐lineage to the remaining eumenines. Eumenes sensu lato as originally recognized is paraphyletic relative to Odynerus sensu lato. A natural classification at the tribal level congruent with the phylogenetic results may be proposed, and the names Zethini, Odynerini, and Eumenini are already available. This is the most comprehensive phylogeny of the Eumeninae to date. A new generic synonymy is Alfieria Giordani Soika, 1934 = Delta de Saussure, 1855.     

Untangling phylogenetic,geometric and ornamental imprints on Early Triassic ammonoid biogeography: a similarity‐distance decay study

Ammonoids are diverse and widespread fossil, externally shelled cephalopods that flourished for more than 300 Myr before their total extinction 65 Ma ago. In spite of two centuries of intensive scientific studies, their mode(s) of life and long‐distance dispersal abilities remain poorly known. Here, we address this by focusing on the latitudinal distribution of Early Triassic (approximately 250 Myr) ammonoids through similarity‐distance decay analyses. We examine and compare rates of similarity‐distance decay between various groups with respect to systematics, shell geometry and ornamentation to untangle phylogenetic, geometric and ornamental imprints on the observed biogeographical pattern. Our data do not support any phylogenetic and shell ornamentation influence, but rather demonstrate the significant effect of (sub‐)adult shell geometry on the similarity–distance decay: most evolute morphs tend to have been more endemic than most involute forms. This contrasts with the classic hypothesis that long‐distance ammonoid dispersal mainly occurred during the earliest planktonic stages, and thus that (sub‐)adult morphological characteristics should not constrain large‐scale biogeographical patterns of ammonoids. Although direct control by Sea Surface Temperature can be discarded, this result may indicate that at least some adult Triassic ammonoid morphs were skilled active swimmers capable of achieving long‐distance migration, as observed for some present‐day coleoid cephalopods. □Ammonoid, dispersal, similarity‐distance decay, morphology, phylogeny, biogeography, Triassic.     

Phylogenetic analysis of cuckoo wasps (Hymenoptera: Chrysididae) reveals a partially artificial classification at the genus level and a species‐rich clade of bee parasitoids

Cuckoo wasps (Hymenoptera: Chrysididae) are a species‐rich family of obligate brood parasites (i.e. parasitoids and kleptoparasites) whose hosts range from sawflies, wasps and bees, to walking sticks and moths. Their brood parasitic lifestyle has led to the evolution of fascinating adaptations, including chemical mimicry of host odours by some species. Long‐term nomenclatural stability of the higher taxonomic units (e.g. genera, tribes, and subfamilies) in this family and a thorough understanding of the family's evolutionary history critically depend on a robust phylogeny of cuckoo wasps. Here we present the results from phylogenetically analysing ten nuclear‐encoded genes and one mitochondrial gene, all protein‐coding, in a total of 186 different species of cuckoo wasps representing most major cuckoo wasp lineages. The compiled data matrix comprised 4946 coding nucleotide sites and was phylogenetically analysed using classical maximum‐likelihood and Bayesian inference methods. The results of our phylogenetic analyses are mostly consistent with earlier ideas on the phylogenetic relationships of the cuckoo wasps' subfamilies and tribes, but cast doubts on the hitherto hypothesized phylogenetic position of the subfamily Amiseginae. However, the molecular data are not fully conclusive in this respect due to low branch support values at deep nodes. In contrast, our phylogenetic estimates clearly indicate that the current systematics of cuckoo wasps at the genus level is artificial. Several of the currently recognized genera are para‐ or polyphyletic (e.g. Cephaloparnops, Chrysis, Chrysura, Euchroeus, Hedychridium, Praestochrysis, Pseudochrysis, Spintharina, and Spinolia). At the same time, our data support the validity of the genus Colpopyga, previously synonymized with Hedychridium. We discuss possible solutions for how to resolve the current shortcomings in the systematics of cuckoo wasp genera and decided to grant Prospinolia the status of a valid genus (Prospinolia stat.n. ) and transferring Spinolia theresae [du Buysson 1900] from Spinolia to Prospinolia (Prospinolia theresae stat.restit. ). We discuss the implications of our phylogenetic inferences for understanding the evolution of host associations in this group. The results of our study not only shed new light on the evolutionary history of cuckoo wasps, but also set the basis for future phylogenomic investigations on this captivating group of wasps by guiding taxonomic sampling efforts and the design of probes for target DNA enrichment approaches.     

A molecular analysis of the Gelechiidae (Lepidoptera,Gelechioidea) with an interpretative grouping of its taxa

We re‐examine the higher level phylogeny and evolutionary affinities of the family Gelechiidae (Lepidoptera: Gelechioidea) based on DNA sequence data for one mitochondrial gene (cytochrome c oxidase subunit I) and seven nuclear genes (Elongation Factor‐1α, wingless, Ribosomal protein S5, Isocitrate dehydrogenase, Cytosolic malate dehydrogenase, Glyceraldehyde‐3‐phosphate dehydrogenase and Carbamoylphosphate synthase domain protein). Fifty‐two taxa representing nearly all established subfamilies and tribes of Gelechiidae, and about 10% of described gelechiid genera, in addition to five outgroup taxa were sequenced. Data matrices (6157 bp total) were analysed under model‐based evolutionary methods (Maximum Likelihood and Bayesian Inference), resulting in novel high‐level phylogenetic interrelationships. The best supported cladogram divided the Gelechiidae into six distinct clades corresponding to the subfamilies Anacampsinae, Dichomeridinae, Apatetrinae, Thiotrichinae, Anomologinae and Gelechiinae (+ Physoptilinae, which were not available for study). The results suggest the following adjustments in gelechiid interrelationships: Brachmini is nested within Dichomeridinae; Anarsiini is the sister group of Chelariini; Pexicopiinae is the sister group of Apatetrinae, here suggested to be treated as a tribe Pexicopiini of Apatetrinae. A new subfamily Thiotrichinae ( subfam.n. ) is proposed on the basis of the resurrected genus Thiotricha Meyrick ( gen.rev. ), which includes Macrenches Meyrick, Palumbina Rondani and Polyhymno Chambers. Gelechiidae display a wide array of life‐history strategies, but the diversity in patterns of larval mode of life has direct phylogenetic correlation only below subfamily level, suggesting multiple origins and/or frequent reversals for traits such as external or internal feeding and leaf mining within the family.     

Phylogenetic significance of the kinethmoid‐associated Y‐shaped ligament and long intercostal ligaments in the Cypriniformes (Actinopterygii: Ostariophysi)

Liao, T.Y. & Kullander, S.O. (2012). Phylogenetic significance of the kinethmoid‐associated Y‐shaped ligament and long intercostal ligaments in the Cypriniformes (Actinopterygii: Ostariophysi). —Zoologica Scripta, 42, 71–87. The phylogenetic significance of the Y‐shaped and long intercostal ligaments in the Cypriniformes is examined using character optimization in 184 species representing 20 non‐ostariophysan teleost species, five ostariophysan orders, seven cypriniform families and 14 cyprinid subfamilies. Character states were optimized on the phylogenetic trees of previous studies. Given the topology of Saitoh et al. (2011) , the Y‐shaped ligament, connecting the kinethmoid to the ethmoid complex, is shown to be a synapomorphy for the Cyprinidae, with reversals observed in the Cyprininae, Danioninae, Gobioninae and Psilorhynchinae. The condition of the Y‐shaped ligament is consistent within most subfamilies with a few exceptions. Despite the exceptions, the Y‐shaped ligament may be considered as a diagnostic character distinguishing cyprinid subfamilies with otherwise similar morphology, that is, the Danioninae and Opsariichthyinae. The long intercostal ligament, connecting five to eight ribs and ascending from the subdistal end of the fifth rib, is present in the Catostomidae and all cyprinid subfamilies, except for the Psilorhynchinae and two developmentally truncated genera, Danionella and Paedocypris. In addition to these two cypriniforme families, the long intercostal ligament is homoplastically present in some catfishes. Given the topology of Saitoh et al. (2011) , presence of the long intercostal ligament is a synapomorphy of Cyprinidae+Catostomidae. Some shorter ligaments are also present in the Cypriniformes and Chilodus gracilis (Characiformes), near the base of the anterior ribs and only occurring anterodorsally to the putative line of the long intercostal ligament even when it is absent.     

Cenozoic mystery birds – on the phylogenetic affinities of bony‐toothed birds (Pelagornithidae)

Mayr, G. (2011) Cenozoic mystery birds – on the phylogenetic affinities of bony‐toothed birds (Pelagornithidae). —Zoologica Scripta, 40, 448–467. The extinct Cenozoic bony‐toothed birds (Pelagornithidae) are characterized by the occurrence of unique spiky projections of the osseous jaws and are among the most distinctive neornithine taxa. Earlier authors considered these marine birds to be most closely related to ‘Pelecaniformes’ or Procellariiformes, but recent phylogenetic analyses resulted in a sister group relationship to Anseriformes. This latter hypothesis was, however, coupled with a non‐monophyly of galloanserine or even neognathous birds, which is not supported by all other current analyses. The character evidence for anseriform affinities of pelagornithids is thus reassessed, and it is detailed that the alleged apomorphies cannot be upheld. Pelagornithids lack some key apomorphies of galloanserine birds, and analysis of 107 anatomical characters did not support anseriform affinities, but resulted in a sister group relationship between Pelagornithidae and Galloanseres. By retaining a monophyletic Galloanseres, this result is in better accordance with widely acknowledged hypotheses on the higher‐level phylogeny of birds. The (Pelagornithidae + Galloanseres) clade received, however, only weak bootstrap support, and some characters, such as the presence of an open frontoparietal suture, may even support a position of Pelagornithidae outside crown‐group Neognathae.     

The phylogeny and revised classification of Machaerotidae,the tube‐making spittlebugs (Hemiptera: Auchenorrhyncha: Cercopoidea)

Machaerotidae (Hemiptera: Auchenorrhyncha: Cercopoidea) is a taxonomically small but morphologically diverse family of spittlebugs with approximately 115 described species in 31 genera and an exclusively Palaeotropical distribution. Results are presented of the first molecular phylogenetic investigation of Machaerotidae, examining relationships among the currently recognized subfamilies and tribes, as well as determining the phylogenetic placement of the genera Enderleinia Schmidt, Neuromachaerota Schmidt, Labramachaerota Bell & Cryan, and Kyphomachaerota Bell & Cryan. DNA nucleotide sequence data from eight loci (12s rDNA, 16s rDNA, 18S rDNA, 28S rDNA, histone 2A, histone 3, wingless and NADH Dehydrogenase subunit 4) were analysed to reconstruct the phylogeny. The evidence generated in this study supports the following systematic conclusions: (i) Machaerotidae is a monophyletic family; (ii) Machaerotini, Hindoloidini (with the new inclusion of Kyphomachaerota), and Enderleiniini (excluding Kyphomachaerota and Apomachaerota Schmidt) are monophyletic tribes; (iii) the genus Apomachaerota was recovered as the most anciently diverged lineage of extant Machaerotidae, and a new subfamily (Apomachaerotinae subfam.n. ), is proposed on the basis of its phylogenetic placement as sister lineage to all other extant Machaerotidae.     

Molecular phylogeny of Nitidulidae: assessment of subfamilial and tribal classification and formalization of the family Cybocephalidae (Coleoptera: Cucujoidea)

We present a molecular phylogeny of Nitidulidae based on thirty ingroup taxa representing eight of the ten currently recognized subfamilies. Approximately 10 K base pairs from seven loci (12S, 16S, 18S, 28S, COI, COII and H3) were used for the phylogenetic reconstruction. The phylogeny supports the following main conclusions: (i) Cybocephalidae are formally recognized as a distinct family not closely related to Nitidulidae and its constituent taxa are defined; (ii) Kateretidae are sister to Nitidulidae; (iii) Cryptarchinae are monophyletic and sister to the remaining nitidulid subfamilies; (iv) subfamily Prometopinae stat. res. is reinstated and defined, to accommodate taxa allied to Axyra Erichson, Prometopia Erichson and Megauchenia MacLeay; (v) Amphicrossinae, Carpophilinae and Epuraeinae are shown to be closely related taxa within a well‐supported monophyletic clade; (vi) tribal affinities and respective monophyly within Nitidulinae are poorly resolved by our data and must be more rigorously tested as there was little or no support for prior morphologically based tribes or genus‐level complexes; (vii) Nitidulinae are found to be paraphyletic with respect to Cillaeinae and Meligethinae, suggesting that they should either be subsumed as tribes, or Nitidulinae should be divided into several subfamilies to preserve the status of Cillaeinae and Meligethinae; (viii) Teichostethus Sharp stat. res. is not a synonym of Hebascus Erichson and the former is reinstated as a valid genus. These conclusions and emendations are discussed in detail and presented within a morphological framework.     

Cryptic yet colorful: anatomy and relationships of a new genus of Cerithiidae (Caenogastropoda,Cerithioidea) from coral reef drop‐offs

Cerithium koperbergi is a rare gastropod of the family Cerithiidae from the tropical Indo‐West Pacific. The species has a small, unusual shell and often inhabits deeper water, fore‐reef habitats that are atypical for the genus. Anatomical investigations reveal that it possesses a combination of features heretofore considered diagnostic of two main cerithiid subfamilies: Cerithiinae and Bittiinae. While the shell is bittiine, the animal lacks mesopodial pedal glands and possesses a seminal receptacle (vs. a spermatophore bursa) in the lateral lamina of the oviduct, which are considered to be cerithiine features. Re‐evaluation of the anatomy of Bittium reticulatum, the type species of Bittium, indicates the defining anatomical difference in oviduct anatomy between the two subfamilies does not stand up to closer scrutiny. Partial mitochondrial cytochrome c oxidase I (COI) sequences support the interpretation that C. koperbergi is a species complex around the western Pacific rim comprising three divergent mitochondrial lineages. Bayesian analysis of partial mitochondrial COI and 16S rRNA sequences confirm the placement of the C. koperbergi complex within a monophyletic Bittiinae, despite the apparent absence of a unifying anatomical feature. Species in the C. koperbergi complex are here united in Pictorium nov. gen. and two species are described as new. It is hypothesized that features of the midgut may be diagnostic of the Bittiinae, but more comparative data are needed.