Posterior Margin Research Articles

Ultrasonic Image Characteristics of Palatine Tonsils in Healthy Children and Analysis of Factors Influencing Image Quality.

To explore the ultrasonic image characteristics of palatine tonsils in healthy children and the factors affecting image quality. A total of 750 images of palatine tonsils were collected from 375 healthy children. According to ultrasonic image quality, the images were divided into three groups. Both systemic and local factors were analyzed among the different groups. The palatine tonsils showed quasi-circular or flat oval, low echo or light and dark band arrangement, a striped medium echo, and a clear boundary. Age, height, weight, body mass index, body surface area, distance from the skin to the posterior margin of the tonsils, thickness of the anterior soft tissue of the tonsils, and thickness of the anterior submandibular gland of the tonsils were significantly different among the different image quality groups (p < 0.05). Multivariate logistic regression analyses revealed that height, weight, thickness of the anterior soft tissue of the tonsils, and thickness of the anterior submandibular gland of the tonsils were independent factors affecting the quality of the ultrasonic images of the palatine tonsils. There are characteristic ultrasonic image manifestations of the palatine tonsils. Tonsil ultrasound image quality is affected by individual and local factors.

Elektroformica azquil gen. et sp. nov., a new formicine ant from Oligo-Miocene Mexican amber

A novel ant genus and species, Elektroformica azquil gen. et sp. nov. is described from Late Oligocene-Early Miocene Mexican amber. It is placed within the subfamily Formicinae based on the presence of an acidopore. It can be distinguished by its diminutive size, elongated scapes that extend beyond the head’s vertex by approximately double the length of the head, eyes located about 2/3 the distance between the mandible’s base and the head’s vertex. Additional diagnostic features include a distinctive keel-shaped clypeus, a prominently marked promesonotal groove, a discontinuous mesonotum with dorsal and declivitous edges, a curved propodeum lacking differentiated anterior and posterior margins, and a markedly reduced node on a thick petiole. Elektroformica azquil gen. et sp. nov. is in syninclusion with deciduous petals and filaments of a flower identified as cf. Hymenaea mexicana, along with elements closely associated with leaf litter and the soil environment. As an extinct taxon endemic to Oligo-Miocene deposits, Elektroformica azquil gen. et sp. nov. enriches the diversity within the subfamily Formicinae and offers valuable insights into the evolutionary history of formicine ants.

A new feather mite species of the genus Temnalges (Acariformes: Psoroptoididae) from coots, Fulica spp. (Gruiformes: Rallidae)

A new feather mite species, Temnalges fulicae sp. n. (Psoroptoididae: Pandalurinae), is described from two species of coots, Fulica americana Gmelin, 1789 (type host), in Canada, and F. atra Linnaeus, 1758, in Denmark. The new species is close to other species of the genus associated with rails (Rallidae), especially to T. megalonyx Gaud, 1968, in having a long spur-like process on tibia III in males, and the prodorsal and hysteronotal shields separated by a wide area of striated tegument in females. Males of Temnalges fulicae are most clearly distinguished from T. megalonyx in having the opisthosoma rounded and without terminal and lateral clefts, and the adanal shields narrow and short. In females, the prodorsal shield has a convex posterior margin, the hysteronotal shield is roughly rectangular, and setae 4a extend to the bases of setae ps3. Additionally, we provide a world checklist and a key to Temnalges species.

Laparoscopic-Assisted, Percutaneous Cryoablation: A Novel Technique for the Treatment of Abdominal Wall Soft Tissue Tumors.

Percutaneous cryoablation is a first-line therapeutic option for primary neoplasms and metastatic lesions of the musculoskeletal system. Treatment of abdominal wall tumors is challenging as surgical resection can be highly morbid and necessitate complex reconstructive surgery; the efficacy of cryoablation for abdominal wall tumors may be limited by inadequate posterior margins owing to the proximity of intra-abdominal organs. With laparoscopy and insufflation, peritoneal structures can be safely mobilized away from the abdominal wall, allowing for adequate deep margin freeze and visualization of the ice ball. We present two patients with abdominal wall soft tissue tumors treated with a novel approach of laparoscopic-assisted, percutaneous ultrasound-guided cryoablation. Patient 1 is a 65-year-old female with metastatic extraskeletal myxoid chondrosarcoma, stable on systemic therapy, who presented with a new soft tissue metastasis to the abdominal wall. Resection would have necessitated a highly morbid complex abdominal wall reconstruction with mesh. Patient 2 is a 35-year-old female with a large abdominal wall desmoid tumor, diagnosed after miscarriage. Resection was relatively contraindicated owing to the morbidity of a complex abdominal wall reconstruction and concerns regarding potential future pregnancies after surgery. Both patients underwent procedures in the outpatient setting after discussion at multidisciplinary sarcoma tumor board. Laparoscopic enterolysis was performed to mobilize the bowel away from the abdominal wall, to allow direct visualization of the peritoneal aspect of the tumor, and to confirm adequacy of the posterior margin freeze of the lesion. Laparoscopic transversus abdominus preperitoneal (TAPP) blocks with local anesthetic were performed for postoperative pain control. Interventional radiology performed an ultrasound-guided cryoablation consisting of two freeze and thaw cycles. Both patients recovered well without complications and were without radiographic evidence of persistent or recurrent disease at 12 and 18 months postoperatively, respectively. We report a novel approach of laparoscopic-assisted cryoablation for the treatment of abdominal wall soft tissue tumors. This allowed for successful minimally invasive local control of these large tumors that would have otherwise required highly morbid resections with complex abdominal wall reconstruction and mesh repair.

Molecular phylogeny reveals a new genus and species of freshwater mussel (Bivalvia, Unionidae, Gonideinae) from Jiangxi, China

Freshwater mussels of the tribe Gonideini (Bivalvia: Unionidae: Gonideinae) constitute one of the most taxonomically diverse groups and serve as keystone species in riverine and lacustrine ecosystems across East Asia. A new genus and species of Gonideini (Bivalvia: Unionidae) is described from Jiangxi, China, as Pseudopostolata angulagen. et sp. nov. based on an integrative analysis of shell morphology and molecular data. The validity of the new genus and species is supported by distinct conchological features: a short, rounded anterior; a long, wide posterior; a slightly downward-curved dorsal margin; and a distinctly obtuse angle at the center of the posterior margin. The multi-locus (COI + 16S rRNA + 28S rRNA) phylogeny showed that the species formed a monophyletic group in the tribe Gonideini of the subfamily Gonideinae. Pseudopostolata angulagen. et sp. nov. is identified as the sister group to a clade comprising the genera Postolata, Cosmopseudodon, Obovalis, Ptychorhynchus, Parvasolenaia, and Koreosolenaia. We emphasize the significant morphological convergence in freshwater mussels, particularly within Gonideini, highlighting the necessity of an integrated taxonomic approach for accurate generic classification of this group.

A new genus of Ambositrinae (Hymenoptera, Diapriidae) from Rovno amber and remarks on the Eocene distribution of the subfamily

Arcanys rostratus Chemyreva gen. et sp. nov. is described from the Eocene Rovno amber in the tribe Betylini (subfamily Ambositrinae) as the first member of this tribe discovered in Europe – in amber and in recent fauna. This new genus differs from other genera of the Ambositrinae by a combination of such features as: the pleurostomal carinae positioned at right angles to each other, the absence of notauli, the propodeum with strongly elevated plicae but without median carina and carina along posterior margin, the fore wings with short marginal and stigmal veins, and the base of T2 deeply arcuated but without notches and elongate grooves. The distribution of the subfamily Ambositrinae is discussed.

Isolated Perianal Langerhans Cell Histiocytosis in a Human Immunodeficiency Virus-Positive Adult: A Rare Incidental finding

Abstract Introduction/Objective Langerhans cell histiocytosis (LCH) is a rare disorder characterized by abnormal proliferation of antigen-presenting cells, primarily Langerhans cells. Although it commonly affects bones, skin, and lungs, involvement of the gastrointestinal tract is rare. Specifically, isolated perianal LCH is exceptionally uncommon, with only a few documented cases reported in the literature. Here, we report a case of incidental perianal LCH in an adult HIV patient, highlighting the exceptional rarity and clinical importance of this occurrence. Methods/Case Report A 56-year-old Caucasian male with HIV underwent surgical resection of a 0.5 x 0.4 x 0.3 cm verrucous lesion on the posterior anal margin. His past medical history included granulomatous lymphadenitis, penile warts, and anal dysplasia. Microscopic examination of the excised tissue revealed Langerhans cells with characteristic features, including abundant eosinophilic cytoplasm and irregular nuclear membranes (resembling “coffee-bean” or “folded paper” appearance). Immunohistochemical analysis confirmed the diagnosis by demonstrating positivity for CD1a, S100, and CD68. The BRAF mutation was evaluated on the same paraffin-embedded block, which revealed the lack of the mutant BRAF V600E. PET-CT imaging showed no evidence of metastatic disease, emphasizing the isolated nature of the perianal LCH in this patient. Results (if a Case Study enter NA) NA Conclusion This case highlights the significance of recognizing and thoroughly evaluating rare and incidental conditions such as LCH in HIV patients. Our findings emphasize the importance of maintaining a high index of suspicion for LCH among healthcare providers and ensuring proper follow-up to rule out systemic involvement. Furthermore, there is a need for future studies to investigate the correlation between LCH and HIV. Given its rarity and diverse clinical presentation in immunocompromised individuals, a multidisciplinary approach, tailored treatment plans, and long-term surveillance with imaging modalities like PET/CT are essential for effectively managing adult-onset isolated LCH.

Clinical value of transperineal ultrasound in evaluating the effects of different delivery methods on the primipara pelvic floor structure and function

To evaluate the effects of different delivery methods on the pelvic floor structure and function among primiparas by transperineal ultrasound, with a view to providing guidance for early postpartum intervention. Primiparas who underwent postpartum examination with transperineal ultrasound were recruited. Subjects were divided according to mode of delivery (vaginal and cesarean delivery). General information (including age, pre-pregnancy BMI and neonatal weight) were collected, and transperineal ultrasound was performed to measure such indicators as the levator hiatus areas in resting, constrictive anal and maximum Valsalva states, the posterior vesicourethral angles and distances between vesical neck and posterior inferior margin of pubic symphysis in resting and maximum Valsalva states, as well as the vesical neck mobility and urethral rotation angle in maximum Valsalva state. The inter-group differences in ultrasound indicators between the resting and Valsalva states were compared to analyze the postpartum incidences of pelvic floor dysfunctions like stress urinary incontinence, urethral funnel formation, bladder prolapse and uterine prolapse in primiparas. The levator hiatus areas in resting, constrictive anal and maximum Valsalva states were all larger in the vaginal delivery group than in the cesarean delivery group (P < 0.05). Compared to the cesarean delivery group, the vaginal delivery group exhibited larger posterior vesicourethral angles in resting and maximum Valsalva states (P < 0.05). The distances between vesical neck and posterior inferior margin of pubic symphysis were greater in the cesarean delivery group than in the vaginal delivery group at both resting and maximum Valsalva, with that at maximum Valsalva showing significant inter-group difference (P < 0.05). The vaginal delivery group exhibited greater vesical neck mobility and urethral rotation angle at maximum Valsalva compared to the cesarean delivery group (P < 0.05). The incidences of stress urinary incontinence, urethral funnel formation, bladder prolapse and uterine prolapse were all higher in the vaginal delivery group than in the cesarean delivery group, with the stress urinary incontinence and bladder prolapse incidences showing significant inter-group differences (P < 0.05). With transperineal ultrasound, various pelvic floor indicators of primiparas can be clearly measured and, through these ultrasound indicators, the effects of different delivery methods on the pelvic floor function can be evaluated, which is conducive to early clinical detection and intervention of postpartum pelvic floor dysfunctions, thus facilitating the early postpartum treatment.

The ankylosaurid neomorphic skull elements

Ankylosaurids but not nodosaurids possess a suite of neomorphic elements fused to the posterior border of the skull roof. Previous authors have offered conflicting descriptions of these elements, leading to ongoing confusion over their morphology, developmental origin, and homologies. They have been described both as secondary dermal additions and as outgrowths of known skull elements. However, they are demonstrably neomorphic and were incorporated into the skull early in ankylosaurid evolution. The six elements—three per side—are herein termed the supranuchal, postsquamosal, and postquadratojugal and form the posterior margin of the skull on each side (in some taxa, the parietal also reaches the posterior border). They do not overlie the squamosal or quadratojugal but rather articulate with them. Other neomorphic elements including the supraorbitals and supranarial ossifications have been described previously. The squamosal proper is a small element in the skull roof with a well-defined cotylus ventrally for articulation with the quadrate. The three neomorphs likely originated as a cervical half-ring or simply as a series of six cervical osteoderms situated just posterior to the skull in ancestral ankylosaurs.

Two new species of the genus Quindina Roewer, 1914 (Opiliones: Nomoclastidae) from Colombia: phylogenetic relationships and notes on their nest architecture

ABSTRACT Quindina Roewer, 1914 is a nomoclastid genus with 11 described species behaviourally characterised by its remarkable nest-building behaviour. In this paper we describe two new Colombian species of the genus from the western range of the Northern Andes, based on genital morphology and external characters. In addition, we explore their phylogenetic relationships using a phenotypic matrix with 96 characters, three newly proposed, and 55 terminals including all described species of Quindina and a wide outgroup sample across the suborder Laniatores. Quindina sanantonio sp. n. (type locality: Valle del Cauca, Santiago de Cali, San Antonio Forest) can be diagnosed by having two olive-green patches behind the ocularium and on the lateral portion of areas II and III, connected on the posterior margin of area III. Quindina horologium sp. n. (type locality: Risaralda, Santuario, Planes de San Rafael) can be diagnosed by having an hourglass-shaped dorsal pattern, beginning as two emerald-green patches next to the ocularium and continuing to the posterior margin of area III. Both species build nests without walls on the underside of leaves (ie flattened nest type), a previously unknown nest architecture for the genus. The phylogenetic analysis confirmed the monophyly of Quindina. The two new species, herein described, were recovered as basally branching within the genus. The inferred ancestral state for the nest architecture was the flattened nest type. We provide an updated key for the Colombian species of the genus Quindina and an updated distribution map. http://www.zoobank.org/urn:lsid:zoobank.org:pub:4C811186-3FAC-4F65-81BD-A5720513551E.

Australian radiographers’ digital era practice in selecting the image receptor angle for female body habitus for the mediolateral oblique view of the breast

IntroductionCorrect alignment of the image receptor (IR) in mammography for the mediolateral oblique (MLO) view of the breast is fundamental to enable the maximum inclusion of breast tissue. This study aims to assess Australian radiographers' knowledge and digital era practice in selecting the IR angle for female body habitus in the MLO view of the breast. MethodsAn online survey was distributed to all members of the Australian Society of Medical Imaging and Radiation Therapy (ASMIRT) through their electronic newsletter and via direct email to radiographers holding the Certificate of Mammographic Practice (CMP). Descriptive analysis was undertaken, and a Pearson's chi-squared test of independence was used to compare associations between academic qualification and IR selection data. A value of p < 0.05 was deemed statistically significant. ResultsA total of 107 valid surveys were returned; 67.3 % reported using the posterior lateral margin to select the IR angle. For linear body habitus, 44.9 % reported using 50°; for all other body habitus, participants most commonly used 45° (59.1 %); 85.1 % used a range of angles between 40 and 55°; 16.8 % recognised the link between correct IR angle selection and breast tissue inclusion. ConclusionThe range of angles used in practice has reduced in the digital era; the frequency of the use of 45° across all body habitus may reflect tube angle movement automation. Few radiographers recognised the important link between correct selection of IR angle and breast tissue inclusion on the image. Implications for practiceUnderstanding of the link between IR angle selection and image quality enhances current practice in the digital era to maximise the inclusion of breast tissue and minimise the potential of missed breast cancer.

311. PROGNOSTIC VALUE OF DIFFERENT CIRCUMFERENTIAL MARGIN SITES IN OESOPHAGEAL CANCER: A 10-YEAR COHORT STUDY

Abstract Background There’s a growing interest towards the prognostic value of circumferential resection margin (CRM) involvement in oesophageal cancers. However, there is no sufficient data about the association of the site-specific CRM and survival. In this study, we analysed the influence of different involved CRM sites on survival. Methods This study included patients who had curative oesophagectomy for oesophageal cancer between 2010 till June 2021. Follow up till April 2022 was achieved. Patients with involved proximal or distal margins were excluded. The sites of CRM were defined anatomically to anterior (pericardial), posterior (aorta), lateral (pleurae). The outcomes between different CRM margins were retrospectively analysed. The long-term follow up data was obtained via direct contact with the patients during our oncological clinics, cross-checked with our hospital/national patients’ electronic databases. Results 117 patients had CRM-positive after curative oesophagectomy during the study period. 33 cases had multi-involved CRM sites, while 84 patients had single involved CRM site. Posterior margins were the most common involved site 37/117 (31.6%). No differences in baseline pathological criteria (pT, pN stages and type of cancer) and neoadjuvant therapy. Positive anterior margins carried the worst overall (OS) and disease-free (DFS) survival compared to lateral and posterior margins (OS: 29 vs 41 vs 32 months respectively, p-value 0.37, DFS: 19.2 vs 32.1 vs 28.7 months respectively, p-value 0.39). Multi-involved CRM sites led to worse OS and DFS in comparison with single involved CRM site (OS: 19 vs 32 months respectively, p-value 0.008, DFS: 12.1 months vs 27.6 months respectively, p-value 0.05). Conclusion The site of involved CRM should be rigorously assessed in oesophagectomy specimens. The involved margin sites within CRM had different survival rates, with inferiority towards anterior resection margins. Larger studies are required to better evaluate the prognostic significance of various CRM sites.

Calliobothrium Narsisae n. sp. (Tetraphyllidea: Calliobothriidae) from the Triakid Shark Mustelus mosis Hemprich and Ehrenberg from the Persian Gulf, with a Note on Its Specific Proglottisation Process and a Key to the Species of the Genus.

The members of the tetraphyllidean genus Calliobothrium exhibit a high degree of host specificity in the shark genus Mustelus. In the Indian Ocean, where M. mosis occurs dominantly, there is no information on Calliobothrium. The purpose of this study was the evaluation of the Calliobothrium species in M. mosis in the Persian Gulf, northwestern Indian Ocean. Nine specimens of Mustelus mosis were caught from the Persian Gulf. The tapeworms isolated were stained, measured, and the line drawings were made. Calliobothrium narsisae n. sp. is described and differs from C. creeveyae in the intact, rather than the three-lobed, posterior bothridial margins, from C. tylotocephalum in possessing three, rather than one, suckers per bothridial muscular pad, from C. nodosum in possessing the elongated, rather than robust and thorn-like, hooks, from C. shirozame in a maximum number of four, rather than three, dorsal and four, rather than three, ventral laciniations along the strobila, and from its other congeners in possessing three, rather than two, dorsal and three, rather than two, ventral laciniations in the anteriormost immature proglottids. A key to the species of the genus is presented and the proglottisation process, by the germinative zone placed in the terminal part of the worm at least in some stages of growth to maturity, is discussed. The description of C. narsisae n. sp., which brings the total number of valid species of Calliobothrium to 10, also indicates that the germinative zone is not always at the anterior to strobila and in this new species it is placed in the terminal part of the worm at least in some stages of growth to maturity.

First Azygiid Reported from Africa or a Characiform Fish: Plenivitellinum kifi n. gen., n. sp. (Digenea: Azygiidae) Infecting the Gut of African Tigerfish, Hydrocynus vittatus Castelnau, 1861 (Characiformes: Alestidae) from the Kavango River.

This paper aims to describe Plenivitellinum kifi n. gen., n. sp. (Digenea: Azygiidae) infecting the gastrointestinal tract of the African tigerfish, Hydrocynus vittatus Castelnau, 1861 (Characiformes: Alestidae) in the Kavango River, Namibia. We revise the diagnosis of Azygiidae Lühe, 1909 to accommodate this new species. The worm was heat-killed, fixed in 10% neutral buffered formalin, stained in Van Cleave's and Ehrlich's hematoxylins, cleared in clove oil, and mounted on glass slide using Canada balsam. The new azygiid resembles species of Otodistomum Stafford, 1904 by having an elongate body, a ventral sucker that is wider than the oral sucker and that is in the anterior half of the body, a pre-testicular ovary, a uterus that primarily occupies the inter-caecal space between the ovary and the ventral sucker, and a vitellarium that is restricted to the hindbody and that is confluent posteriorly in the post-testicular region. The new genus differs from all species of Azygiidae by having the combination of a ventral sucker that is wider than the oral sucker (vs. narrower), an elongate prostatic sac that extends posteriad to near the posterior margin of the ventral sucker (vs. an ovoid prostatic sac that is wholly anterior to or slightly overlaps the anterior margin of the ventral sucker), a vitellarium that nearly fills the post-testicular space and that extends posteriad beyond the caecal tips (vs. a vitellarium that is separate posteriorly or that is restricted to the anterior half of the post-testicular space and does not extend posteriad beyond the caecal tips), and an I-shaped excretory bladder (vs. Y-shaped). This study documents the first record of an azygiid from Africa and the first record of an azygiid infecting a characiform fish.

Glyptothorax pongoensis, a new species of rheophilic catfish (Sisoridae) from the Brahmaputra River drainage, Nagaland, India

ABSTRACT Glyptothorax pongoensis, sp. n. is described from the Yongmon River in Nagaland, India. The new species can be distinguished from its congeners in the Indian subcontinent by the following combination of characters: an ovate-shaped thoracic adhesive apparatus with skin ridges present over the entire apparatus, including the subulate-shaped median depression; presence of plicae on the ventral surface of the pectoral fin spine and the first ray of the pelvic fin; W-shaped anterior nuchal plate element; dorsal-fin origin nearer to the snout tip than to the origin of the adipose fin; posterior margin of dorsal spine rugose with 4–5 ridges, tuberculate skin, and nasal barbel not reaching eye when adpressed. http://www.zoobank.org/urn:lsid:zoobank.org:pub:5D71008D-5D28-4C77-9FA2-D5074DDA7BC9

New species of Kontrimavichusia Makarikov &amp; Binkienė, 2022 (Eucestoda: Hymenolepididae) from arvicoline rodents (Rodentia: Cricetidae) from the North Caucasus

Two previously unrecognized species attributable to the genus Kontrimavichusia Makarikov &amp; Binkienė, 2022 in arvicoline rodents from the North Caucasus are described. Kontrimavichusia testiculata sp. nov. is described from Microtus majori (Thomas, 1906) from the northwestern Caucasus (Republic of Adygeya and Karachay-Cherkess Republic, Russia) and Kontrimavichusia hobergi sp. nov. is described from Microtus daghestanicus (Shidlovsky, 1919) from the central Caucasus (Republic of North Ossetia, Russia). Kontrimavichusia testiculata is readily distinguishable from K. asymmetrica (Janicki, 1904) and K. hobergi in having a larger number of testes (4–6 per proglottis), larger suckers and a longer cirrus and cirrus-sac. In addition, the new species differs from its congeners by the position of the cirrus-sac with regard to the poral osmoregulatory canals and position of distal end of the rostellar pouch relative to the posterior margins of the suckers. Kontrimavichusia hobergi can be readily distinguished from its congeners by the arrangement of the testes in a triangle and the position of the cirrus-sac with regard to the poral osmoregulatory canals. In addition, this previously unrecognized species differs from K. asymmetrica and K. testiculata by the smaller dimensions of the fully developed strobila and a narrower ovary. The cirrus-sac of K. hobergi is larger than that in K. asymmetrica but smaller than that in K. testiculata. We also used partial sequences of the nuclear ribosomal 28S rRNA gene and mitochondrial nad1 gen to justify the generic arrangement and independent status of these two new species which are characterized in the current manuscript.

Dutrapona, a new genus and three new species of Gyponini (Insecta: Hemiptera: Cicadellidae) from Central and South America

A new leafhopper genus of the tribe Gyponini, Dutrapona gen. nov., is proposed and described based on males of three newly described species from Central and South America: Dutrapona tenuis sp. nov. (type species) from Alajuela, Costa Rica, Dutrapona reticulata sp. nov. from Napo, Ecuador, and Dutrapona zahniseri sp. nov. from Coclé, Panama. The new genus resembles genera of the Hecalapona complex in sharing characteristics such as: body yellow without maculae and dorsoventrally flattened, crown moderately produced with anterior margin rounded and projected over anterior margins of eye, crown-face transition distinct and thin, maxillary plates narrow and not extending to clypeus apex and forewing with narrow appendix. However, Dutrapona gen. nov. can be distinguished from other Gyponini genera by the combination of the following of characteristics: ocelli positioned closer to midline and posterior margin of the crown, crown-face transition spatulate with two well defined carinae, male sternite VIII longer than wide, male pygofer with a pair of small caudal denticulated processes, subgenital plates short, and aedeagus with a pair of basilateral elongate processes.

Reducing the Wallacean and the Haeckelian Deficits in Apobaetis Day, 1955 (Ephemeroptera: Baetidae).

During an ongoing project aiming to understand the dynamics of Ephemeroptera biodiversity in the Doce River Basin after the disaster, an unusual large number of Apobaetis Day, 1955 were analyzed. The occurrence of Apobaetis is quite relevant, since the combination of factors such as its small body size and its habitat preferences makes their collection difficult and its presence often neglected. For the first time in science, adults of Apobaetis irai De Lima, Massariol, Cruz & Hamada, 2022 and Apobaetis fiuzai Salles & Lugo-Ortiz, 2002 are described and diagnosed. Apobaetis irai can be easily distinguished, among other characteristics by turbinate portion of compound eyes touching each other along midline; abdominal terga II-III and V-VII with well-marked lines on lateral and posterior margins; posterior margin of subgenital plate with projection broadly rounded to slightly truncate. Apobaetis fiuzai are diagnosed by turbinate portion of compound eyes touching each other posteriorly; mesothorax brown, except for broad cream marks on anterior margin of PSp and SLS, SSLi tinged with white, posterior corner of SMS with a red spot; abdominal terga II-VI translucent orangish-brown, terga VII-X brown, terga II-III and VI with conspicuous red medial mark; posterior margin of subgenital plate with subtriangular projection, apex narrowly truncate; forceps base wider at base, inner irregular edges. The new records of A. irai and A. fiuzai extend the distribution of Apobaetis within Minas Gerais and Espírito Santo States, Brazil. Furthermore, it is reported for the first time cases of gynandromorphs for Apobaetis.

A new genus of Herpyllobiidae (Copepoda: Cyclopoida) from a deep-living annelid (Polychaeta: Sigalionidae).

A taxonomic study of deep-sea polychaetes collected at a depth of 2,805 m off the northern coast of California revealed a scaleworm of the family Sigalionidae with an attached parasitic copepod. The copepod represents an undescribed genus of the family Herpyllobiidae, comprising mesoparasitic copepods chiefly recorded from polychaetes of the family Polynoidae. Blakerius gen. nov. diverges from the other herpyllobiid genera by its possession of 1) a chalice-shaped ectosoma with several protuberances along the posterior margin and a long cylindrical shaft with a hyaline coating and integumental sculpturing, a short stalk with a small, anteriorly placed sclerotized ring, 2) a relatively large, discoid-shaped endosoma with digitiform process, and 3) attached male copepodids with 3-segmented antennules, containing limbless sac-like males. The new genus is compared with other herpyllobiids. This discovery increases the number of known herpyllobiid genera to six and is the first record of a herpyllobiid parasitizing a sigalionid polychaete.urn: lsid: zoobank.org:pub:5E31FEED-D3EB-460E-AEA4-02A9D3A778D6.

Biomechanical Study of Symmetric Bending and Lifting Behavior in Weightlifter with Lumbar L4-L5 Disc Herniation and Physiological Straightening Using Finite Element Simulation.

Physiological curvature changes of the lumbar spine and disc herniation can cause abnormal biomechanical responses of the lumbar spine. Finite element (FE) studies on special weightlifter models are limited, yet understanding stress in damaged lumbar spines is crucial for preventing and rehabilitating lumbar diseases. This study analyzes the biomechanical responses of a weightlifter with lumbar straightening and L4-L5 disc herniation during symmetric bending and lifting to optimize training and rehabilitation. Based on the weightlifter's computed tomography (CT) data, an FE lumbar spine model (L1-L5) was established. The model included normal intervertebral discs (IVDs), vertebral endplates, ligaments, and a degenerated L4-L5 disc. The bending angle was set to 45°, and weights of 15 kg, 20 kg, and 25 kg were used. The flexion moment for lifting these weights was theoretically calculated. The model was tilted at 45° in Abaqus 2021 (Dassault Systèmes Simulia Corp., Johnston, RI, USA), with L5 constrained in all six degrees of freedom. A vertical load equivalent to the weightlifter's body mass and the calculated flexion moments were applied to L1 to simulate the weightlifter's bending and lifting behavior. Biomechanical responses within the lumbar spine were then analyzed. The displacement and range of motion (ROM) of the lumbar spine were similar under all three loading conditions. The flexion degree increased with the load, while extension remained unchanged. Right-side movement and bending showed minimal change, with slightly more right rotation. Stress distribution trends were similar across loads, primarily concentrated in the vertebral body, increasing with load. Maximum stress occurred at the anterior inferior margin of L5, with significant stress at the posterior joints, ligaments, and spinous processes. The posterior L5 and margins of L1 and L5 experienced high stress. The degenerated L4-L5 IVD showed stress concentration on its edges, with significant stress also on L3-L4 IVD. Stress distribution in the lumbar spine was uneven. Our findings highlight the impact on spinal biomechanics and suggest reducing anisotropic loading and being cautious of loaded flexion positions affecting posterior joints, IVDs, and vertebrae. This study offers valuable insights for the rehabilitation and treatment of similar patients.