Hook Size Research Articles

Influence of Circle Hook Size on Catch Rate and Size of Red Grouper in Shallow Waters of the Southern Gulf of Mexico

AbstractHigh rates of undersized catch and discard mortality are common in fisheries for Red Grouper Epinephelus morio in the Gulf of Mexico and Atlantic Ocean. Reducing undersized catch rate in these fisheries requires more effective regulation of the minimum size limit (MSL). One potential method is to regulate hook selectivity for target species. Three circle hook sizes (11/0, 12/0, and 13/0) were tested to assess the effect of hook size on Red Grouper catch rate and size in the shallow waters of the Yucatan Peninsula coast, which is the primary fishing zone for the region's small‐scale grouper (family Epinephelidae) fishery. Red Grouper was always the numerically dominant species in catches (76–81%) for all hook sizes. Hook size did not affect mean catch rate. Significantly longer fish were caught in the 13/0 hook size treatment than in the 11/0 and 12/0 treatments, which did not differ. Nonetheless, when considering the MSL regulation applicable in Mexico's Red Grouper fishery (36.3 cm TL), high percentages of undersized Red Grouper were still caught, regardless of hook size. The hook sizes required in the Yucatan small‐scale fishery (10/0–12/0) provide little if any improvement in Red Grouper MSL regulation. Real improvement would require the effective release of undersized fish as well as a reduction in the number of undersized specimens caught and in potential cryptic sources of fish release mortality (e.g., barometric trauma). Furthermore, the current applicable Red Grouper MSL only really attempts to control growth overfishing and ignores recruitment overfishing.Received December 22, 2014; accepted September 3, 2015

Gear selectivity of fishery target resources in Lake Koka, Ethiopia: evaluation and management implications

We evaluated the statistical models that best describe the selectivity of common fishing gears used in Lake Koka for four freshwater species widely distributed in Ethiopia and elsewhere: tilapia Oreochromis niloticus (L.), catfish Clarias gariepinus (B.), common carp Cyprinus carpio (L.), and barb Labeobarbus intermedius (R.). Sampling was conducted from October 2012 to March 2013 using gillnets (60, 80, 100, and 120 mm stretched mesh), longlines (4/0, 6/0, and 8/0 hooks size), and a beach seine with covered codend. Size at maturity (L m) was determined for each species. The SELECT method was used to explore unimodal selectivity models for gillnet and longline gears, while the logistic function was used for beach seine. Results show that a log-normal model best described gillnet selectivity for all species, while a normal scale model best described longline selectivity for C. gariepinus. Gillnets with ≥100 mm mesh and longlines with >4/0 hooks could be safely used, as they allow target resources to attain L m before becoming vulnerable to fishing. The mesh size of the beach seine needs to be enlarged, as the estimated length of capture was much smaller than all L m values. The results have important management implications for protecting juveniles and mega-spawners of the studied species in Lake Koka and beyond.

Description and phylogenetic affinities of two new species of Nomadolepis (Eucestoda, Hymenolepididae) from Eastern Palearctic

Two new species of hymenolepidid cestodes belonging to the genus Nomadolepis are described from small mammals in western Siberia and the Far East, Russian Federation. Nomadolepis fareasta n. sp. is described from the striped dwarf hamster Cricetulus barabensis in Amurskaya Oblast' and Nomadolepis shiloi n. sp. is described from the Eurasian harvest mouse Micromys minutus from Novosibirskaya Oblast' and Amurskaya Oblast'. Nomadolepis fareasta n. sp. differs from Nomadolepis merionis, Nomadolepis ellobii and N. shiloi n. sp. in having a substantially longer strobila, longer cirrus-sac and wider ovary. Furthermore, N. fareasta n. sp. can be readily distinguished from its congeners by the arrangement of the testes and the number and size of rostellar hooks. Nomadolepis shiloi n. sp. differs from N. merionis, N. ellobii and N. fareasta n. sp. by the number and length of the rostellar hooks, the presence of irregular transverse anastomoses as well as the length of the cirrus-sac and position of the cirrus-sac in relation to the poral ventral osmoregulatory canal. Morphological differentiation of the two new species from morphologically similar Palearctic species of the related genus Rodentolepis (sensu lato) from rodents is also provided. Phylogenetic affinities of Nomadolepis were studied for the first time using partial sequences of the nuclear ribosomal 28S DNA gene. Phylogenetic analysis strongly supported the status of Nomadolepis as a separate genus closest to Pararodentolepis.

Internal Fixation Using Clavicle Hook Plates for Distal Clavicle Fractures

Background: To report the radiological and clinical outcomes of internal fixation using distal clavicle hook plates for distal clavicle fractures. Methods: From April 2008 to December 2012, 32 patients with distal clavicle fractures underwent surgery using an AO hook plate. The reduction was qualified and evaluated according to the radiological findings. The evaluation of the clinical outcomes was performed with the University of California at Los Angeles (UCLA) score, the Korean Shoulder score, and the visual analogue scale (VAS) pain score. Results: By radiological evaluation, we found that 31 of 32 patients showed anatomical reduction and solid bone union. Although we obtained satisfactory UCLA scores, Korean Shoulder Scale scores, and VAS pain scores, 12 cases of complications were present. We found 4 cases of osteolysis of the acromion, 1 case of nonunion, 3 cases of periprosthetic fractures, 3 cases of subacromial pain, and 1 case of skin irritation. We performed re-operations in 2 patients. Conclusions: To avoid complications associated with clavicle hook plates, choosing the appropriate hook size and bending of the hook according to the slope of the acromion undersurface is critical. Also, we believe that early removal of clavicle plates may help reduce complications.

Hooking locations in sea turtles incidentally captured by artisanal longline fisheries in the Eastern Pacific Ocean

Bycatch by longline fisheries, especially by artisanal small-scale fisheries, is one of the main conservation problems for some sea turtle populations around the world. Since 2004, a network of professionals under the “Eastern Pacific Regional Sea Turtle Bycatch Program” have been working with artisanal longline fishers in the Eastern Pacific Ocean (EPO) to reduce sea turtle bycatch and related mortality. Trials assessing circle hooks of different sizes and shapes, and different baits, have been conducted to determine the effectiveness in the reduction of sea turtle bycatch and changes in hooking location. In this paper, information from 1823 olive ridley sea turtles incidentally captured in the EPO were analyzed to assess how hook type (J, tuna hooks or circle hooks), hook size, bait type (squid or fish), turtle size and target species (tunas, sharks or mahi-mahi) affect hooking location on sea turtles. This were modeled with a Classification and Regression Tree using hooking location as a multinomial variable response (for 6 categories of hooking locations); and also as a binomial response (swallowed vs. non-swallowed) using a Generalized Linear Mixed Model (GLMM). Hook type and size, plus bait type, were the most important factors affecting hooking location, while turtle size and target species did not have any significant effect. J-hooks and tuna hooks had a much greater probability of being swallowed than circle hooks. In addition, as the hook size increased, the likelihood of swallowing it decreased. The use of fish bait in combination with larger circle hooks tended to produce higher proportions of external hookings. An increase in external or lower mandible hookings is preferred since these locations are assumed to be less dangerous for the animal's post-release survival, and because hooks and attached gear are easier to remove by well-trained fishermen.

Effect of wire diameter and hook location on second bond failure modes

Purpose – This paper aims to analyze the effect of Au wire size and location of hook during wire pulling test to identify the variation of results obtained. Design/methodology/approach – Two hook locations, namely, location A and location B were used to analyze the effect of hook location. Location A was the same as the hook location required by MIL-STD-883E standard, whereas location B was located near to the second bond. The correlation between new purposed failure modes and MIL-STD-883E standard was developed to reflect on the pull strength with the physical failure. Findings – It was observed that fine pitch Au wire has higher variation and lower process capability of pull strength. Au wire pulled by the hook at location B provides a more representative result compared to that at location A. Fifty per cent or more of Au remnant is required to be considered as a good and reliable Au wedge bond based on the new purposed failure modes. Originality/value – The evaluation of gold (Au) wedge bond requires a new proper wire pulling test method. This is due to the large variation obtained from the application of current practice of wire pulling test.

Revisiting Echinorhynchid Acanthocephalans in Lake Baikal with the Use of Scanning Electron Microscopy, with some Taxonomic Reconsiderations

Ten species of acanthocephalans are known from 30 species of fish in Lake Baikal. Three species in the family Echinorhynchidae were studied and reported: (1) Echinorhynchus salmonis Müller, 1784 ( = Metechinorhynchus salmonis (Müller 1784) Petrochenko, 1956), previously designated as Echinorhynchus salmonis baicalensis Bogolepova, 1957 (actually Dogiel and Bogolepova, 1957) that we consider invalid. Echinorhynchus s. baicalensis was studied from whitefish Coregonus lavaretus (Linnaeus, 1758) (Family Salmonidae) in Chivyrkui Bay and from Kessler's (sand) sculpin Leocottus kesslerii (Dybowski, 1874) (Family Cottocomephoridae) at Goryachinsk on the eastern shore of Lake Baikal in Pribaikalsk District, Republic of Buryatia. Our scanning electron microscopy observations demonstrate miniapical proboscis hooks, hooks with dorsal indentation, 2 anteroventral trunk bumps, and variable position of male and female gonopores, for the first time. (2) Echinorhynchus cinctulus (Porta, 1905) Amin, 2013 ( = Pseudoechinorhynchus borealis (von Linstow, 1901) Petrochenko, 1956) was studied from burbot, Lota lota (Linnaeus, 1758) (Family Lotidae) in Chivyrkui Bay and Khankh. The thorny hooks, inconsistencies in proboscis armature, hook size, dermal micropores, and position of male and female gonopores are reported. (3) Echinorhynchus truttae Schrank, 1788 ( = Metechinorhynchus truttae (Schrank, 1788) Petrochenko, 1956) was studied from L. kesslerii in Goryachinsk. Features of the proboscis, hooks, female gonopore, dermal micropores, and eggs are presented.

Four new species of Acanthobothrium van Benden, 1850(Cestoda: Onchoproteocephalidea) from the guitarfish, Rhynchobatus cf. djiddensis (Elasmobranchii: Rhynchobatidae), from the Persian Gulf and Gulf of Oman.

Four new species of Acanthobothrium van Beneden, 1850 are described from guitarfish, Rhynchobatus cf. djiddensis (Forsskål), collected from the Gulf of Oman and Persian Gulf. Acanthobothrium janineae sp. n., a category 1 species, differs from all congeners in category 1 by having a long vagina extending into the vas deferens and different, proglottid and testis number except Acanthobothrium hypermekkolpos Fyler et Caira, 2010. Acanthobothrium fylerae sp. n., a category 1 species, can be differentiated by a combination of characters including the total length, proglottid and testis number, cirrus sac shape, and the length of the vagina and ovarian lobes. Both new species are similar to A. hypermekkolpos reported from Rhynchobatus laevis (Bloch et Schneider) from Australia in their scolex proper length, hook size and muscular pad, respectively. Acanthobothrium asrinae sp. n., a category 1 species, differs from other category 1 species by the shape of its hooks and the position of the tubercle at the mid-length of the axial prongs; in this respect it resembles A. bartonae Campbell et Beveridge, 2002 reported from Australia. Acanthobothrium jamesi sp. n. is among six category 1 species with post-ovarian testes. It differs from these species by total length, proglottid and testis number and the extension of the ovarian lobes. Although it is thought that R. djiddensis occurs in the region, the identities of the hosts of the newly described Acanthobothrium species await verification. There are two forms of host in the region and were designated as R. cf. djiddensis 1 and R. cf. djiddensis 2. More taxonomic work and the use of molecular techniques are needed to resolve the true identity of the host species.

Effect of bait and gear type on channel catfish catch and turtle bycatch in a reservoir

Hoop nets have become the preferred gear choice to sample channel catfish Ictalurus punctatus but the degree of bycatch can be high, especially due to the incidental capture of aquatic turtles. While exclusion and escapement devices have been developed and evaluated, few have examined bait choice as a method to reduce turtle bycatch. The use of Zote™ soap has shown considerable promise to reduce bycatch of aquatic turtles when used with trotlines but its effectiveness in hoop nets has not been evaluated. We sought to determine the effectiveness of hoop nets baited with cheese bait or Zote™ soap and trotlines baited with shad or Zote™ soap as a way to sample channel catfish and prevent capture of aquatic turtles. We used a repeated-measures experimental design and treatment combinations were randomly assigned using a Latin-square arrangement. Eight sampling locations were systematically selected and then sampled with either hoop nets or trotlines using Zote™ soap (both gears), waste cheese (hoop nets), or cut shad (trotlines). Catch rates did not statistically differ among the gear–bait-type combinations. Size bias was evident with trotlines consistently capturing larger sized channel catfish compared to hoop nets. Results from a Monte Carlo bootstrapping procedure estimated the number of samples needed to reach predetermined levels of sampling precision to be lowest for trotlines baited with soap. Moreover, trotlines baited with soap caught no aquatic turtles, while hoop nets captured many turtles and had high mortality rates. We suggest that Zote™ soap used in combination with multiple hook sizes on trotlines may be a viable alternative to sample channel catfish and reduce bycatch of aquatic turtles.

Histopathological and morphological studies on natural Cysticercus fasciolaris infection in liver of Wistar rats.

Descriptive morphology of multifocal hepatic cysts found in eight of forty five (17.78%) Wistar rats sacrificed during pharmacological studies related to herbal formulations was studied. The creamish to white cysts were of varying sizes, ranging from 3-8mm in diameter. Morphological studies of these cysts depicted the presence of metacestodes of Taenia taeniaeformis i.e. Cysticercus fasciolaris inside them. The scolex of metacestode revealed four suckers and rostellum armed with two distinct rows of characteristic pen knife shaped hooks (characteristics of taeniid cestodes). The average size of large hooks was 392.92±10.12µ and that of small hooks was 240.64±14.26µ. The average size of suckers was 304.36±12.33µ. Histopathology of hepatic tissue surrounding the cysts revealed zones of fatty change, inflammation, granulation tissue and metaplasia. However, the histopathology of stomach and small intestines didn't show any significant lesions.

Hook selectivity of Giant Trevally (Caranx ignobilis) and Nakedbreast Trevally (Carangoides gymnostethus) (Carangidae) caught in the hook-and-line fishery off Negombo, Sri Lanka

In the present study, an attempt was made to quantify hook selectivity of two carangid species (Caranx ignobilis and Carangoides gymnostethus) which were predominantly caught in the hook-and-line fishery off Negombo, Sri Lanka. As the length frequency data of C. ignobilis and C. gymnostethus recorded by hook size were skewed towards the larger fish, a modification of Baranov-Holt method for gillnet selection was employed. For both species there were positive significant relationships (p<0.001) between the hook size and optimal length while selection range was negatively related to hook size (p<0.001). DOI: http://dx.doi.org/10.4038/sljas.v16i0.6712 Sri Lanka J. Aquat. Sci. 16 (2011): 11-26

Effect of Pin Length on Hook Size and Joint Properties in Friction Stir Lap Welding of 7B04 Aluminum Alloy

Friction stir lap welding of 7B04 aluminum alloy was conducted in the present paper, and the effect of pin length on hook size and joint properties was investigated in detail. It is found that for each given set of process parameters, the size of hook defect on the advancing side shows an “M” type evolution trend as the pin length is increased. The affecting characteristics of pin length on joint properties are dependent on the heat input levels. When the heat input is low, the fracture strength is firstly increased to a peak value and then shows a decrease. When the heat input is relatively high, the evolution trend of fracture strength tends to exhibit a “W” type with increasing the pin length.

Estimation of Hook Selectivity of Red Snapper and Vermilion Snapper from Fishery‐Independent Surveys of Natural Reefs in the Northern Gulf of Mexico

AbstractImplementation of circle hook regulations in the Gulf of Mexico will impact the length structure and age structure of the snapper–grouper fishery catch as well as demographic data for stock assessments; therefore, an understanding of circle hook selectivity patterns is critical. Indirect selectivity analysis of the vertical‐line catch of Red Snapper Lutjanus campechanus and Vermilion Snapper Rhomboplites aurorubens showed that for both species, there were significant differences in mean FL among hook sizes, broad length frequency distributions, and wide selectivity curves. Although the results suggest that hook size regulations could be a useful management strategy for targeting desired size‐classes of these snappers, the broadly overlapping length distributions indicate that undersized catch would not be eliminated. Selectivity curves generated from the different families of distributions produced equally good fit to the data and provided a basis for evaluating various selectivity curves when the size structure of the sampled population is unknown. If the size structure of the population is known, then the use of direct selectivity methods is recommended. Right‐skewed distributions generally fit the data best, suggesting that hook regulations are likely to be more effective if the desired goal is to reduce the amount of undersized catch by eliminating small hook sizes. Conversely, elimination of large hooks appears to be less likely to reduce the catch of larger size‐classes because mouth gape is likely the primary limiting factor and small hooks can catch large fish. Catch rates were significantly different among hook sizes; thus, regulations based on hook size could impact fishing effort and change the dynamics of how the snapper–grouper fishery is prosecuted. Tradeoffs between moderate improvements in size‐class targeting, changes in effort, and various components of fishing mortality (i.e., catch and regulatory discards) will require further investigation through simulation modeling or field experimentation.Received April 23, 2014; accepted September 16, 2014

Experimental Assessment of Circle Hook Performance and Selectivity in the Northern Gulf of Mexico Recreational Reef Fish Fishery

AbstractCircle hooks are required when targeting reef fishes in the U.S. federal waters of the Gulf of Mexico. However, limited data is available to evaluate circle hook performance (e.g., hooking location and catch rate) or selectivity in this fishery. Therefore, a fishing experiment was conducted to test the performance of a range of circle hook sizes (2/0 and 4/0 Mustad 39940BLN and 9/0, 12/0, and 15/0 Mustad 39960D) in the recreational reef fish fishery, as well as to estimate hook selectivity directly for Red Snapper Lutjanus campechanus, the most targeted reef fish in the northern Gulf of Mexico. Reef fish communities were surveyed with a micro remotely operated vehicle equipped with a laser scaler and then fished with one of five circle hook sizes. Hooking location typically was in the jaw for all hooks examined, with the mean percentage of jaw hooking being 94.1% for all reef fishes and 92.9% for Red Snapper. Fish size generally increased with hook size but at the cost of a reduced catch rate. The percentage of the catch constituted by Red Snapper decreased from 73% for 2/0 hooks to 60% for 9/0 hooks but then increased to 84% for 15/0 hooks. Dome‐shaped (exponential logistic) selectivity functions resulted when fitting candidate models to hook‐specific Red Snapper size at catch and remotely operated vehicle laser‐scaled size distribution data. While Red Snapper median size at full selectivity increased with circle hook size, the difference in that parameter between the smallest and largest hooks was only 66 mm, or a difference of approximately one age‐class. Results of this study suggest that mandating the use of large (e.g., ≥12/0) circle hooks would have relatively little effect on either Red Snapper catch rate or selectivity but would decrease the catch rate for other reef fishes, which would be problematic during closed Red Snapper seasons when fishermen attempt to target other species.Received February 19, 2014; accepted July 29, 2014

Finike Körfezi’nde Sargoz (Diplodus sargus L.,1758) Balığı Avcılığında Kullanılan Dip Paraketasının Seçiciliği

In this study, the selectivity of different hook size in the bottom longline which used for catc-hing white seabream (Diplodus sargus L., 1758) in Finike Bay were compared. In the calcula-tion of selectivity parameters of fishhooks, Holt (1963) method was used. 13 fishing operation were carried out during study period, a total number of 200 hooks used in each fishing opera-tion and 293 number of fishes was captured during study period. Selectivity parameters were calculated for white seabream for two hooks gap size of which are 0.72 and 0.63. The optimum capture length (Lopt) for 0.72 and 0.63 cm gap size were de-termined as 23.31 and 20.40 respectively, also the selectivity factor was determined as 32.37. A linear relationship between fish sizes and the gap size of hooks was found.

A historical review of selectivity approaches and retrospective patterns in the Pacific halibut stock assessment

The Pacific halibut stock assessment has proven to be a particularly challenging application for the estimation of selectivity. Contributing factors include: extremely pronounced temporal changes in length-at-age, a steep vulnerability curve for commonly used hook sizes, a minimum length limit, relatively late (∼age 6–10) appearance of fish in survey and fishery data, and geographic heterogeneity in demographic parameters coupled with pronounced spatial trends in population abundance over time and significant ontogenetic migration over the stock range. Historical stock assessments have variously modeled selectivity as a function of length or age, employing nonparametric forms in attempting to account for these various factors. Despite these efforts, a strong retrospective bias in model results occurred during three separate time periods; each of which ultimately required modification of the selectivity parameterization to ameliorate that bias. This paper provides a summary of historical approaches, and the methods employed to address the most recent retrospective pattern.

New cold-water coral occurrences in the Eastern Ionian Sea: Results from experimental long line fishing

Our knowledge on the cold-water corals (CWCs) occurring in the deep waters of Eastern Ionian Sea (E. Mediterranean) has improved with new species records and information related to their occurrence, abundance, distribution, morphological and other characteristics. Data were collected from accidental coral catches during experimental long-line fishing using two different hook sizes (No. 7 targeting hake and No. 9 targeting blackspot seabream). Eight coral taxa were identified, with new records for the E. Ionian Sea for Antipathes dichotoma, Desmophyllum dianthus, Swiftia pallida and Pennatula phosphorea. CWCs occurred in 72% of the long lines and most of them were entire and live (except Leiopathes glaberrima). The most frequently caught coral group was Antipatharia. Isidella elongata and A. dichotoma presented the highest abundance. The main bulk of the corals was caught between 500 and 600m depth. Some of the identified corals (L. glaberrima and I. elongata) seemed to have more close relationships with some species of the fish assemblage (Galeus melastomus, Helicolenus dactylopterus) inhabiting the study area. Species richness and coral catch in numbers were higher for the smaller hook size (No. 9), which caught the larger entire living colonies of A. dichotoma, L. glaberrima and I. elongata. As a result, the corals collected during the present study, characterized by slow growth rates and high longevities, could be considered vulnerable to the gear used in blackspot seabream fishery; this implies the need for more research, monitoring, protection and sustainable management.

Anglers' perceptions of recreational fisheries and fisheries management in Mallorca

The growing relevance of recreational fisheries has increased the need for acceptable, workable and sustainable policies. Identifying the regulatory preferences and perceptions of anglers can assist in determining fishers' behaviors and improving the management of coastal fisheries. In this case study of Mallorca Island, Spain, we investigated anglers' perceptions using data obtained from questionnaires. The anglers' responses were somewhat contradictory. They reported pleasure as a main motivation, although fish consumption was also deemed very important. Anglers reported a positive attitude toward licensing, managers, and management rules. They appreciated fishing access restrictions (e.g., closed seasons and marine protected areas MPAs), but they did not consider these restrictions to be effective. The management option that was least favored but considered to be the most effective was that of catch-and-release, which sets minimum size restrictions and requires the release of 20% of captures. A hook size restriction was considered an effective and positive measure, although most anglers admitted that they did not know the hook size they used. If one control measure was to be eliminated, the anglers' preferences were split between removing bag limits and ending the catch and release policy for some sizes and species. Anglers' understanding of management measures was limited and based primarily on person-to-person communication. Communication with managers was functionally unidirectional and primarily consisted of an instruction booklet issued with each fishing license. The use of electronic communication tools (i.e., web pages) was very low. The quality of communication between fisheries agencies and the fishing public may challenge management credibility and affect compliance with regulations.

Trypanorhynch cestodes from elasmobranchs from the Gulf of Oman, with the description of Prochristianella garshaspi n. sp. (Eutetrarhynchidae)

In a study on the order Trypanorhyncha Diesing, 1863, a total of 35 specimens belonging to nine species of elasmobranch in the Gulf of Oman, was examined. The following trypanorhynch species were identified: Pterobothrium lesteri Campbell & Beveridge, 1996, Otobothrium carcharidis (Shipley & Hornell, 1906), Eutetrarhynchus platycephali Palm, 2004, Parachristianella indonesiensis Palm, 2004, Pa. monomegacantha Kruse, 1959 and Prochristianella mooreae Beveridge, 1990. Prochristianella garshaspi n. sp. is described from Pastinachus sephen (Forsskål) and Rhinoptera sp. The new species is allocated to the genus Prochristianella Dollfus, 1946 on the basis of the presence of two bothria, prebulbar organs, and a heteroacanthous typical tentacular armature with relatively few hooks in each principal row, hollow hooks increasing in size from antibothrial and then decreasing towards the bothrial surface of the tentacle, hooks 1 and 1' being separated, and a basal swelling with characteristic billhooks increasing in size towards the bothrial surface. The lack of microscopically visible microtriches on the scolex distinguishes the new species from P. hispida (Linton, 1890), P. clarkeae Beveridge, 1990, P. thalassia (Kovaks & Schmidt, 1980), P. multidum Friggens & Duszynski, 2005 and P. cairae Schaeffner & Beveridge, 2012. Prochristianella garshaspi n. sp. can be distinguished from the remaining species within the genus by a combination of the following morphological features: the presence of numerous gland-cells within the tentacular bulbs, the number of rows on the basal swelling, the number of hooks per half spiral row, the size of the principal hooks, the number of the testes and the presence of an external seminal vesicle.

The molecular and morphometrical description of a new diplozoid species from the gills of the Garra rufa (Heckel, 1843) (Cyprinidae) from Turkey—including a commentary on taxonomic division of Diplozoidae

The paper presents a description of Paradiplozoon bingolensis sp. n. from the gills of Garra rufa Heckel, 1843 (Cyprinidae) collected from the Göynük Stream, a tributary of the Murat River, Turkey. This is the first diplozoid species to be described from G. rufa. P. bingolensis is distinguished from the other valid species in the genus by the combination of the morphology of the sclerites of its clamps and by the size of the central hooks. Even molecular characterization based on variability of the second internal transcribed spacer (ITS2) of the ribosomal DNA region provided additional support of separation of this new species from the valid ones. The sequences were compared with previously published ITS2 sequences of other diplozoid species. Subsequent analysis demonstrated the uniqueness of this new parasite species and revealed uncertainties in the current taxonomic division of the Diplozoidae that are commented in the text.