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The Eocene catostomid fish (Cypriniformes: Catostomidae) from the Allenby Formation, British Columbia, Canada, is reviewed and revised based on recently collected specimens. The fish was originally recognized as a catostomid by Cope in 1893 and described as Amyzon brevipinne. Wilson comprehensively redescribed the species in 1977 based on a large collection. More specimens collected recently brought to light the need for a systematic revision of this species, different from all known Amyzon species in having a narrow frontal bone with elongated orbital notch, shallow and slender infraorbital series, broad opercle, and short and slender rib 4. It differs from the type species Amyzon mentale in having a shorter posteroventral process of the dentary and fewer dorsal fin rays. Given the differences from all known Eocene catostomid species, Amyzon brevipinne is herein assigned to a new genus as Wilsonium brevipinne. Phylogenetically, this species is resolved as the most basal taxon of Catostomidae. The small-sized fluvial specimens of Wilsonium brevipinne represent the first recognized dwarf catostomid species in the fossil record (maximum standard length ∼ 84 mm). It is also worth noting that Wilsonium gen. nov. differs from all known catostomids in the elongated orbital notch, shallow and slender infraorbital series and non-robust rib 4. These features are seen in some loaches and gyrinchelids. [ABSTRACT FROM AUTHOR]

The relationship between June sucker (Chasmistes liorus, Jordan, 1878) and Utah sucker (Catostomus ardens, Jordan & Gilbert, 1881) has been a matter of controversy since the mid 1900s. Chasmistes liorus is endemic to Utah Lake, UT and has a subterminal mouth adapted for pelagic feeding. Catostomus ardens is widely distributed throughout the Bonneville Basin and Upper Snake River Basin and has a ventral mouth adapted for benthic feeding. Chasmistes has been recognized as a separate ancient genus. Despite being morphologically distinct, no study has successfully identified residual genetic markers that separate these species. Of these studies, several have used a subset of mitochondrial genes, but no study has analyzed the complete mitochondrial genomes (mitogenomes) of these suckers (Pisces: Catostomidae). To further explore the genetic relationships between these species, we report the complete mitogenomes of Chasmistes liorus and Catostomus ardens. DNA was sequenced using an Illumina HiSeq 2500 system and mitogenomes were assembled and annotated using Geneious v. 2021.2 and MitoAnnotator, respectively. The mitogenomes of Chasmistes liorus and Catostomus ardens are both 16,623 bp and are ∼0.072% divergent. We examine the phylogenetic relationship between Chasmistes liorus and Catostomus ardens using 33 mitogenomes, representing 16 species, from Catostomidae. Our data suggest that Chasmistes liorus is sister to Catostomus ardens. Additional samples from multiple localities and/or cohorts of these species will allow us to better resolve the complicated phylogenetic relationships between these species. [ABSTRACT FROM AUTHOR]

The genetic diversity of the three major artificially propagated populations of Chinese sucker, an endangered freshwater fish species, was investigated using the sequences of mitochondrial DNA (mtDNA) control regions. Among the 89 individuals tested, 66 variable sites (7.26%) and 10 haplotypes were detected (Haplotype diversity Hd = 0.805, Nucleotide diversity π = 0.0287). In general, genetic diversity was lower in artificially propagated populations than in wild populations. This reduction in genetic diversity may be due to population bottlenecks, genetic drift and human selection. A stepping-stone pattern of gene flow was detected in the populations studied, showing much higher gene flow between neighbouring populations. To increase the genetic diversity, wild lineages should be introduced, and more lineages should be shared among artificially propagated populations. [ABSTRACT FROM AUTHOR]

In the literature, a reference terminology for labelling octopus arms exists, but a convention for the labelling of octopus suckers is so far lacking. The precise identification and subsequent ability to address a specific sucker is impossible without some type of convention. In this work, we propose an Octopus Sucker Identification Code, with three/five characters, depending on whether the octopus species has one or two rows of suckers. Specifically, two characters identify the arm to which the sucker belongs, one integer identifies the sucker position along the arm and two subscript characters (present in cases of octopus species with two rows of suckers) identify the adjacent arm towards which the sucker is faced. The proposed code allows the unequivocal identification of the suckers of any octopus arm of any octopus species. [ABSTRACT FROM PUBLISHER]

Banana Xanthomonas wilt (BXW) caused byXanthomonas campestrispv.musacearum(Xcm) is a devastating disease of bananas in Uganda and across the Great Lakes region of East and Central Africa. While use of disease-free suckers is recognized as important to control BXW, bacterial movement from infected mother plants to their suckers is not well understood. In this study, the movement of Xcm through the pseudostem of naturally and artificially infected bananas was examined. In naturally infected plants, samples of plant organs collected from susceptible cultivars ‘Kayinja’, ‘Nfuuka’ and Kivuuvu’ (Musa acuminata) at various stages of disease were analysed using a polymerase chain reaction assay employing Xcm specific primers.Xanthomonas campestrispv. musacearumwas detected in 70% of asymptomatic corms and suckers collected from each of the three susceptible cultivars. In ‘Kayinja’ and ‘Nakitembe’, Xcm was recovered from plant parts 20 cm away from the point of inoculation prior to symptom development. The population of Xcm was variable within and among the plant parts over time, with the highest number being recorded in the inoculated region for all cultivars. No disease was observed seven days after inoculation of the Xcm-resistant wild speciesM. balbisianaand Xcm was restricted to the point of inoculation. This study implies that by the time wilt symptoms are expressed, Xcm has migrated from the point of entry to most parts of the plants. Use of suckers from infected plants should be restricted as they are likely to be latently infected and could thus result in disease when transplanted. [ABSTRACT FROM PUBLISHER]

We examined between-reader precision of age estimates of scales and pectoral fin rays for 123 highfin carpsuckers (Carpiodes velifer), 174 quillback carpsuckers (C. cyprinus), and 135 river carpsuckers (C. carpio). Precision of age estimates was assessed through measures of agreement, the coefficient of variation (CV), and a confidence rating. Exact agreement between readers was higher for fin rays (highfin carpsucker = 82.1%; quillback carpsucker = 75.9%; river carpsucker = 77.0%) than scales (highfin carpsucker = 69.5%, quillback carpsucker = 68.9%; river carpsucker = 71.1%). In addition, CV was lower for fin rays (highfin carpsucker = 2.28; quillback carpsucker = 2.43; river carpsucker = 2.90) than scales (highfin carpsucker = 2.95; quillback carpsucker = 3.00; river carpsucker = 3.46). Fin rays were also assigned a higher confidence rating (i.e., mean readability, 0-3 with 3 being high; highfin carpsucker = 2.22; quillback carpsucker = 1.95; river carpsucker = 1.92) than scales (highfin carpsucker = 1.53; quillback carpsucker = 1.51; river carpsucker = 1.68). [ABSTRACT FROM AUTHOR]

Resource selection analyses of telemetry data are often conducted on categorical measurements of use and availability. Refinement of early resource selection analysis techniques has resulted in use of individuals as the sample unit rather than the number of telemetry detections. However, the minimum number of telemetry detections required for an individual animal to be included as a sample unit must reflect the number of detections needed to accurately describe the individual's resource use. We developed a method to determine the minimum number of detections required to accurately describe categorical resource use of an animal. The mean standard selection ratio (MSSR) described herein can be used to effectively design telemetry projects and efficiently allocate field resources by knowing, a priori, the number of telemetry detections needed to explain resource selection for individual animals and ultimately for an animal population. Additionally, the MSSR technique can be used following data collection to determine the detection level needed for inclusion of individuals in categorical resource selection analyses. [ABSTRACT FROM AUTHOR]

Fishes were collected in four mainstem reaches and eight tributary reaches in the Keya Paha River basin during May and June 2002. Most reaches were characteristically run habitats with sand substrates and riparian pastures. Data were combined with historical records to construct a basin-wide ichthyofaunal list which comprised 38 species from seven families. Dominant species were sand shiners (Notropis ludibundus; 47%), red shiners (Cyprinella lutrensis; 37%), and brassy minnows (Hybognathus hankinsoni; 8%). Dominant game species were bluegill (Lepomis machrochirus) and channel catfish (Ictalurus punctatus). We found one species previously listed as rare in South Dakota-plains topminnow (Fundulus sciadicus), and four species not previously found in the Keya Paha River - silver chub (Macrhybopsis storeriana), river carpsucker (Carpiodes carpio), northern pike (Esox lucius), yellow perch (Perca flavescens). [ABSTRACT FROM AUTHOR]

Presents a study which investigated the abundance biological characteristics of the blue sucker in the James River and the Big Sioux River, South Dakota. Materials and methods; Results; Discussion.

Presents a study that detected the historic levels of genetic diversity in the Chinese sucker (Myxocyrinus asiaticus Bleeker) by using DNA fingerprinting on blood samples collected between 1949 and 1952. Comparison of the historic DNA with that of breeding stock from 2002; Impact of overfishing and large dams on the wild populations of the Chinese sucker; Demonstration of reduced genetic variability in a farmed population of the Chinese sucker by DNA fingerprinting.

In this study, the complete mitogenome sequence of Chinese sucker Myxocyprinus asiaticus (Cypriniformes, Catostomidae) has been amplified and sequenced by employing long polymerase chain reaction method. The mitogenome, consisting of 16,636 base pairs (bp), had the typical vertebrate mitochondrial gene arrangement, including 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs genes, and a noncoding control region (CR). CR of 944 bp length is located between tRNAPro and tRNAPhe. The overall base composition of M. asiaticus is 28.62% for A, 27.90% for C, 24.8% for T, and 18.70% for G, with a slight AT bias of 53.40%. The complete mitogenome may provide important DNA molecular data for further phylogenetic analyses for higher taxa of teleost fishes especially for the members of Cypriniformes. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome ofIctiobus cyprinelluswas first determined by a polymerase chain reaction-based sequencing method in this study. The mitochondria was 16,611 bp in length, including 13 protein genes, 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes and 1 control region. All genes were encoded on the heavy strain except for ND6 and eight tRNA genes. The gene arrangement ofI. cyprinelluswas similar to those found in the other Catostomidae species. Base composition of the heavy strain was A (29.40%), T (24.86%), C (27.96%), G (17.78%) and with A + T bias of 54.26%. [ABSTRACT FROM AUTHOR]