Secondary Sexual Characteristics Research Articles

Demographic and evolutionary consequences of hunting of wild birds.

Hunting has a long tradition in human evolutionary history and remains a common leisure activity or an important source of food. Herein, we first briefly review the literature on the demographic consequences of hunting and associated analytical methods. We then address the question of potential selective hunting and its possible genetic/evolutionary consequences. Birds have historically been popular models for demographic studies, and the huge amount of census and ringing data accumulated over the last century has paved the way for research about the demographic effects of harvesting. By contrast, the literature on the evolutionary consequences of harvesting is dominated by studies on mammals (especially ungulates) and fish. In these taxa, individuals selected for harvest often have particular traits such as large body size or extravagant secondary sexual characters (e.g. antlers, horns, etc.). Our review shows that targeting individuals according to such genetically heritable traits can exert strong selective pressures and alter the evolutionary trajectory of populations for these or correlated traits. Studies focusing on the evolutionary consequences of hunting in birds are extremely rare, likely because birds within populations appear much more similar, and do not display individual differences to the same extent as many mammals and fishes. Nevertheless, even without conscious choice by hunters, there remains the potential for selection through hunting in birds, for example by genetically inherited traits such as personality or pace-of-life. We emphasise that because so many bird species experience high hunting pressure, the possible selective effect of harvest in birds and its evolutionary consequences deserves far more attention, and that hunting may be one major driver of bird evolutionary trajectories that should be carefully considered in wildlife management schemes.

Nutritional considerations for gender-diverse people: a qualitative mini review.

Dietitians working with gender-diverse people may require different skills and knowledge than those caring for cisgender men and women, as indicated by a growing body of literature that highlights gender-diverse people's unique experiences with and relationships to nutrition and eating behaviors. To provide insight into how dietitians can best serve this population, this mini review identifies and summarizes qualitative studies that investigate gender-diverse people's lived experiences and perspectives regarding nutrition, eating disorders, and access to eating-related healthcare services. Fourteen studies examining nutrition or eating behaviors among gender-diverse samples were selected through a systematic search and screening process: 11 focused on disordered eating or eating disorders and the remaining three focused on nutritional needs, nutritional knowledge, and food insecurity. Extracted themes included: using dietary restriction to suppress secondary sex characteristics or conform to societal norms; the impact of gender-affirming care on disordered eating; negative experiences with, and beliefs about, nutrition and eating disorders healthcare services; and suggestions for clinicians. Recommendations discuss the need for increased trans literacy among clinicians, the creation of safe spaces for gender-diverse people with eating disorders, and the importance of dual competencies in eating disorders treatment and gender-affirming care.

Flanged males have higher reproductive success in a completely wild orangutan population.

Male orangutans (Pongo spp.) exhibit bimaturism, an alternative reproductive tactic, with flanged and unflanged males displaying two distinct morphological and behavioral phenotypes. Flanged males are larger than unflanged males and display secondary sexual characteristics which unflanged males lack. The evolutionary explanation for alternative reproductive tactics in orangutans remains unclear because orangutan paternity studies to date have been from sites with ex-captive orangutans, provisioning via feeding stations and veterinary care, or that lack data on the identity of mothers. Here we demonstrate, using the first long-term paternity data from a site free of these limitations, that alternative reproductive tactics in orangutans are condition-dependent, not frequency-dependent. We found higher reproductive success by flanged males than by unflanged males, a pattern consistent with other Bornean orangutan (Pongo pygmaeus) paternity studies. Previous paternity studies disagree on the degree of male reproductive skew, but we found low reproductive skew among flanged males. We compare our findings and previous paternity studies from both Bornean and Sumatran orangutans (Pongo abelii) to understand why these differences exist, examining the possible roles of species differences, ecology, and human intervention. Additionally, we use long-term behavioral data to demonstrate that while flanged males can displace unflanged males in association with females, flanged males are unable to keep other males from associating with a female, and thus they are unable to completely mate guard females. Our results demonstrate that alternative reproductive tactics in Bornean orangutans are condition-dependent, supporting the understanding that the flanged male morph is indicative of good condition. Despite intense male-male competition and direct sexual coercion by males, female mate choice is effective in determining reproductive outcomes in this population of wild orangutans.

(248) Evaluation of Androgen Receptor Signaling and Saturation in Erectile Dysfunction

Abstract Introduction Testosterone (T) is a steroid hormone responsible for the development and maintenance of male secondary sex characteristics. T exerts this physiologic function throughout by binding to the androgen receptor (AR). It is unclear how AR function varies as a function of serum T. Objective We hypothesized that there is a saturation value for the AR above which excess serum T does not lead to increased binding or downstream signaling. This study evaluated whether varied serum T levels were associated with AR signaling in the penile tissue of men with erectile dysfunction (ED). Methods The mean age of participants was 61 (IQR 8.5) years. The mean serum T level was 300.2 (IQR 231.3). The results of the western blot showed that HO and PDE-5 signaling was decreased in men with serum T less than 200 ng/dL compared to those with serum T above 200, while AR and iNOS expression was decreased in men with serum T less than 300 ng/dL compared to those with serum T above 300. Results Within a wide range of serum T values, AR signaling was similar in penile tissue above 200-300 ng/dL. These findings provide a possible explanation for why PDE5 inhibitors are most effective in men with serum testosterone levels greater than 200 ng/dL, as our western blot results indicate that PDE-5 signaling is diminished in men with lower serum testosterone levels. This suggests that maintaining eugonadal levels of serum androgens is essential for optimal functioning of PDE-5 inhibitors. Conclusions Our findings suggest that there is a limit to the effect of serum testosterone levels on AR signaling, as the downstream activity appears to plateau beyond a certain point of receptor activation. Disclosure No.

A new Chinese Cyclogethes pollen beetle, with an updated key to species of the genus and notes on its phylogenetic positioning (Coleoptera: Nitidulidae: Meligethinae).

A peculiar new species of the genus Cyclogethes Kirejtshuk, 1979, C. tibialis sp. nov., is described from Southwestern China (Yunnan). The new species appears to be morphologically rather isolated from the other known members of this essentially Oriental genus (including half a dozen species from Northern Indian subcontinent, Northern Indochina, and Southwestern China). However, it could be more closely related to C. abnormis Kirejtshuk, 1979 from Northern India, Indochina, and Southwestern China, and to C. aldridgei Kirejtshuk, 1980 from Northern India and Nepal, from which it is easily distinguished by the more elongate body shape, and by the markedly sinuate hind tibiae in both sexes (a very unusual character state in Meligethinae, where only males of some species exhibit sexual secondary characters in the tibial shape). The new species also differs from other known taxa of the genus by the shape of the male and female genitalia. The larval hostplants of members of Cyclogethes are thus far unknown, although some clues, also involving the new species described herein, may suggest a relationship with small trees or shrubs of the family Asteraceae. Preliminary and incomplete molecular data on a studied member of the genus (C. abnormis) seems to not disagree with a phylogenetic positioning of Cyclogethes in a clade including the African genera Tarchonanthogethes Audisio & Cline, 2009, its allied Afrotropical taxa, and the Palaearctic genera Meligethes Stephens, 1830 and Brassicogethes Audisio & Cline, 2009. The article includes an updated identification key for all six known species of this genus and an updated map of their known geographic distribution.

A new species of the genus Celaenorrhinus Hbner, [1819] from Hainan, China (Lepidoptera, Hesperiidae).

A new species, Celaenorrhinus qianhanae Li & Liu sp. nov., is described from Hainan, China. Its unique genital characteristics and wing markings are compared with other congeneric species from this island and adjacent regions, including Vietnam and China, etc. In addition, its COI gene is sequenced for molecular analysis, and the secondary sexual character, hair tufts on hind tibiae, is discussed for comparison.

Interaction of 17α-ethinylestradiol and methyltestosterone in western mosquitofish (Gambusia affinis) across two generations

The interactions between estrogen and androgen in aquatic animals remain largely unknown. In this study, two generations (F0 and F1) of western mosquitofish (Gambusia affinis) were continuously exposed to 17α-ethinylestradiol (EE2, 10 ng/L), methyltestosterone (MT, 10 ng/L (MTL); 50 ng/L (MTH)), and mixtures (EE2+MTL and EE2+MTH). Various endpoints, including sex ratio (phenotypic and genetic), secondary sex characteristics, gonadal histology, and transcriptional profile of genes, were examined. The results showed that G. affinis exposed to MTH and EE2+MTH had a > 89.7 % of phenotypic males in F1 generation, with 34.5 and 50.0 % of these males originated from genetic females, respectively. Moreover, females from F0 and F1 generations exposed to MTH and EE2+MTH exhibited masculinized anal fins and skeletons. The combined effect of MT and EE2 on most endpoints was dependent on MT. Furthermore, significant transcriptional alterations in certain target genes were observed in both the F0 and F1 generations by EE2 and MT alone and by mixtures, showing some degree of interactions. These findings that the effects of EE2+MTH were primarily on the phenotypic sex of G. affinis in offspring generation suggest that G. affinis under chronic exposure to the binary mixture contaminated water could have sex-biased populations.

Mosaic Form of Turner Syndrome

Objective: To report a case of breast growth disorder in a mosaic form of Turner Syndrome. Turner syndrome is a chromosomal condition characterized by small height and primary ovarian insufficiency that affects one in every 2500 female births. Mosaicism is likely to occur when monosomy X develops in only a few cells during development. The clinical presentation of Turner syndrome mosaicism is atypical, with symptom severity varying based on the number of affected cells. This case discusses issues with secondary sex development, including mild hyperandrogenism, and explores how combination hormonal treatment can aid in enhancing secondary sex development.
 Method: Case Report.
 Case: A 21-year-old woman presented with chief complaint of the lack of breast enlargement. She exhibited normal genitalia internally and externally and had a regular menstrual cycle. Karyotyping revealed a mosaic pattern of 45, X/46, XX (1 percent/99%) with normal estradiol levels and elevated testosterone levels (indicating mild hyperandrogenism). The patient underwent two cycles of hormone therapy using Ethinyl Estradiol and Drospirenone, resulting in breast growth progression from Tanner stage 1 to Tanner stage 2.
 Conclusion: Mosaicism in Turner syndrome is plausible, and the severity of clinical symptoms correlates with the number of defective chromosomes. The presentation of Turner syndrome mosaicism varies, and therapy should be tailored to address specific symptoms. While breast development is observed in some girls with Turner Syndrome, instances of breast growth disorder may occur, involving estrogen activity and estrogen receptor sensitivity. Although the exact cause of impaired breast growth remains unknown, administering estrogen in such cases can improve secondary sexual characteristics.
 Keywords: mild hyperandrogenism, mosaicism, turner syndrome

The value of luteinizing hormone basal values and sex hormone-binding globulin for early diagnosis of rapidly progressive central precocious puberty.

This study aimed to investigate the diagnostic value of luteinizing hormone (LH) basal values and sex hormone-binding globulin (SHBG) for rapidly progressive central precocious puberty (RP-CPP). A total of 121 girls presenting with secondary sexual characteristics were selected from the Department of Pediatric Endocrinology, Lianyungang Clinical Medical College of Nanjing Medical University, from May 2021 to June 2023. The children were followed up for 6 months and were divided into three groups: RP-CPP group (n=40), slowly progressive central precocious puberty (SP-CPP) group (n=40), and premature thelarche (PT) group (n=41). The differences in LH basal values and SHBG among girls in the three groups were compared. ROC curves were drawn to analyze the value of LH basal values and SHBG in identifying RP-CPP. Significant differences were observed in age, height, predicted adult height (PAH), weight, body mass index (BMI), bone age (BA), BA-chronological age (CA), LH basal, LH peak, FSH basal, LH peak/FSH peak, estradiol (E2), testosterone, and SHBG levels between the RP-CPP group and the SP-CPP and PT groups (P < 0.05). The LH basal value in the RP-CPP group was higher than that in the SP-CPP group and the PT group, while SHBG levels were lower than in the latter two groups, and these differences were statistically significant (P < 0.05). When the LH basal value was ≥0.58 IU/L and SHBG was ≤58.79 nmol/L, the sensitivity for diagnosing RP-CPP was 77.5% and 67.5%, and the specificity was 66.7% and 74.1%. Detection of basal LH and SHBG levels allows for early diagnosis of the progression of central precocious puberty.

Magnetic resonance imaging for proper diagnosis and management of Müllerian duct anomalies

The objective of this study was to highlight the importance of magnetic resonance imaging (MRI) in achieving an accurate early diagnosis and facilitating precise treatment planning for Müllerian duct anomalies (MDAs). To discuss this topic, we present two case reports.Case 1: a 19-year-old nulliparous female presented with primary amenorrhea and normal secondary sexual characteristics. Vaginal inspection revealed a shortened vagina, but no discernible cervix. Transvaginal ultrasound (US) subsequently showed an oval structure initially thought to be the cervix, but no visible uterus or ovaries. MRI eventually confirmed a diagnosis of Mayer–Rokitansky–Küster–Hauser (MRKH) syndrome, with an absence of a uterus, cervix and upper section of the vagina, and the presence of a median fibrous remnant. Case 2: a 24-year-old nulliparous female presented with severe dysmenorrhea and uterine tenderness upon physical examination. Initial US evaluation pointed to bilateral hydrosalpinx. Pelvic MRI finally confirmed a left unicornuate uterus with a rudimentary non-communicating right cavity and associated hematosalpinx. The patient underwent surgical removal of the right rudimentary horn and fallopian tube.These cases demonstrate how MRI yields a much more detailed evaluation of the anatomy of the pelvic region. Early diagnosis and appropriate treatment can significantly reduce the risk of complications and enhance outcomes.

Gender Affirming Hormone Treatment for Trans Adolescents: A Four Principles Analysis

Gender affirming hormone treatment is an important part of the care of trans adolescents which enables them to develop the secondary sexual characteristics congruent with their identified genders. There is an increasing amount of empirical evidence showing the benefits of gender affirming hormone treatment for psychological health and social well-being in this population. However, in several countries, access to gender affirming hormone treatment for trans adolescents has recently been severely restricted. While much of the opposition to gender affirming hormone treatment for trans adolescents has in part been ideologically motivated, it also reflects a debate about whether there are harms that outweigh the benefits of the treatment. Accordingly, a systematic and comprehensive philosophical analysis of the ethics of gender affirming hormone treatment for trans adolescents is needed. Herein, I offer such an analysis that draws on the four principles of biomedical ethics by Tom Beauchamp and James Childress. Based on the considerations of beneficence, nonmaleficence, autonomy, and justice, I argue that the provision of access to gender affirming hormone treatment for consenting trans adolescents is ethically required and that the current restrictions to such treatment are ethically wrong.

A new subterranean species of Entomoculia Croissandeau, 1891 from the Canary Islands, Spain (Coleoptera, Staphylinidae, Leptotyphlinae)

The genus Entomoculia Croissandeau, 1891, is the only representative of the subfamily Leptotyphlinae present in the Canary Islands and is composed by only two species: E. (Stenotyphlus) canariensis Outerelo, 1982, from La Gomera and E. (Stenotyphlus) lauricola Outerelo &amp; Hernández, 1989, from Tenerife, both found in deep soil (= endogean) habitats. In this paper, we describe Entomoculia (Stenotyphlus) vulcanicasp. nov., the third Canarian species of the genus, which is reported for the first time from Gran Canaria and has been found in the mesovoid shallow substratum “MSS”. This new species has some of the characteristics that are specific to Canarian species of the genus Entomoculia, such as the lack of a denticle or spiniform process on the male metatrochanters. However, it is a remarkable species as it is the only known species of the genus with a tridentate labrum, as the labrum is monodentate in the species so far known from Canary Islands and bidentate in non-Canary species. We provide a key to Canarian species and illustrations of the habitus and the primary and secondary sexual characters of the male. We also describe the sampling techniques used and provide detailed information on habitat characteristics and associated arthropod fauna.

Analysis of the differentially expressed genes in the combs and testes of Qingyuan partridge roosters at different developmental stages

BackgroundThe sexual maturity of chickens is an important economic trait, and the breeding of precocious and delayed puberty roosters is an important selection strategy for broilers. The comb serves as an important secondary sexual characteristic of roosters and determines their sexual precocity. Moreover, comb development is closely associated with gonad development in roosters. However, the underlying molecular mechanism regulating the sexual maturity of roosters has not yet been fully explored.ResultsIn order to identify the genes related to precocious puberty in Qingyuan partridge roosters, and based on the synchrony of testis and combs development, combined with histological observation and RNA-seq method, the developmental status and gene expression profile of combs and testis were obtained. The results showed that during the early growth and development period (77 days of age), the development of combs and testis was significant in the high comb (H) group versus the low comb (L) group (p < 0.05); however, the morphological characteristic of the comb and testicular tissues converged during the late growth and development period (112 days of age) in the H and L groups. Based on these results, RNA-sequencing analysis was performed on the comb and testis tissues of the 77 and 112 days old Qingyuan Partridge roosters with different comb height traits. GO and KEGG analysis enrichment analysis showed that the differentially expressed genes were primarily enriched in MAPK signaling, VEGF signaling, and retinol metabolism pathways. Moreover, weighted correlation network analysis and module co-expression network analysis identified WNT6, AMH, IHH, STT3A, PEX16, KPNA7, CATHL2, ROR2, PAMR1, WISP2, IL17REL, NDRG4, CYP26B1, and CRHBP as the key genes associated with the regulation of precocity and delayed puberty in Qingyuan Partridge roosters.ConclusionsIn summary, we identified the key regulatory genes of sexual precocity in roosters, which provide a theoretical basis for understanding the developmental differences between precocious and delayed puberty in roosters.

The Amalgamated Sophomore-Gonadoblastoma

Gonadoblastoma emerges as a benign gonadal neoplasm composed of germ cells and descendants of sex cord-stromal cells reminiscent of immature granulosa cells and Sertoli cells. Neoplasm is preponderantly associated with disorders of sexual development wherein majority (~80%) of neoplasms articulate phenotypic females. Tumefaction expounds primary amenorrhea and delayed sexual maturation with delayed development of genitalia and emergence of secondary sexual characters. Gonadoblastoma locus appears to be situated adjacent to Y centromere wherein TSPY gene is implicated in carcinogenesis. Commonly discerned distinct morphological configurations appear comprised of spherical or irregular clusters of immature Sertoli cells admixed with germ cells and circumscribing basement membrane. Intervening stroma exhibits enlarged, polygonal cells simulating Leydig cells admixed with focal calcification. Germ cells appear immune reactive to p53, placental alkaline phosphatase (PLAP), CD117/c-KIT and VASA protein or encoded testis specific Y protein. Testicular gonadoblastoma requires segregation from neoplasms such as Sertoli cell tumour. Genetic karyotyping is an essential investigation for distinguishing individuals with intersex disorders and potential occurrence of gonadoblastoma. Surgical extermination is a recommended mode of therapy for alleviating gonadoblastoma.

Substantiation of the methodology for assessing the biological age of adolescents.

Aim: To substantiate the methodology for assessing the biological age of adolescent high schoolers (boys and girls). Materials and Methods: Boys aged 14-15 (n = 102) and girls aged 12-13 (n = 101) were studied. The choice of these age groups is explained by the presence of the most significant individual differences in morphological and functional characteristics in these adolescents. Methods: anthropometry, somatometry, somatoscopy, tonometry, spirometry, dynamometry, Stange's test, Rufier and Robinson indices. The interaction of the results of different methods of assessing biological age was conducted on one sex-age sample using factor analysis (principal components method). Results: It has been established that the biological age of adolescents can be reliably determined using a set of three components: an assessment of the level of physical development, the index of heterochronicity, and the degree of manifestation of secondary sexual characteristics (for boys with a probability of 90.2 %, for girls - 92.1 %). The percentage ratio of these components has sexual peculiarities. Methodologies for assessing biological age for scientific purposes and rapid assessment for use in the practice of physical education and sports have been proposed. The indicators of rapid assessment are body length and the degree of hair development in the axilla. The reliability of the rapid assessment is 81.4 % for boys and 83.2 % for girls. Conclusions: Developing adequate physical activities for adolescents of different biological ages will help improve the physical health of the younger generation.

The Role of Hormonal Imbalances in Amenorrhea

Amenorrhea, the absence of menstrual periods in women of reproductive age, is a multifaceted and clinically significant gynecological condition that can have various underlying causes and far-reaching implications for a woman’s overall health and well-being. This abstract provides a concise overview of amenorrhea, encompassing its classification, etiology, clinical presentation, and management. Amenorrhea can be categorized into two primary types: Primary and secondary. Primary amenorrhea refers to the absence of menstruation by the age of 16 years in the presence of normal secondary sexual characteristics, or by the age of 14 years with no signs of puberty. Secondary amenorrhea, on the other hand, is characterized by the cessation of regular menstruation for at least three cycles or six months in women with a history of regular menstruation. The etiology of amenorrhea is diverse and may be attributed to various factors including hormonal imbalances, structural abnormalities in the reproductive tract, excessive exercise, stress, and eating disorders. Polycystic ovary syndrome (PCOS) and hypothalamic amenorrhea are common hormonal causes, while Asherman’s syndrome and structural abnormalities in the uterus are anatomical factors contributing to amenorrhea. The clinical presentation of amenorrhea varies depending on its underlying cause but often includes symptoms such as changes in weight, hair growth patterns, and breast development. An accurate diagnosis requires a comprehensive evaluation, which may involve hormonal assays, imaging studies, and sometimes a biopsy. The management strategies for amenorrhea depend on this cause. Hormone therapy, lifestyle modifications, and surgical interventions are recommended to address hormonal imbalances, structural abnormalities, or other contributing factors. Psychosocial support and counseling play crucial roles in the management of amenorrhea, especially when related to eating disorders or psychological stress.

Efeitos anátomo-fisiológicos da castração pré-púbere em felinos (Felis catus) – revisão de literatura

Pre-pubertal castration in felines is a highly effective strategy for managing stray animal populations, thereby benefiting both public health and animal welfare. It helps prevent unwanted pregnancies, minimizes human-stray animal conflicts, and curtails the spread of diseases transmitted through mating. However, this practice has sparked debates among veterinarians and pet owners due to potential adverse effects. Surgical and anesthetic complications, including hypothermia and hypoglycemia, are concerns during pediatric procedures. There is also a possibility of altered development of secondary sexual characteristics, although these changes typically do not impact the animals' overall well-being. Metabolically, neutered cats tend to gain weight, raising the risk of obesity and diabetes mellitus. Skeletal concerns involve delayed bone closure, yet bone density remains largely unaffected. Lower urinary tract issues, like incontinence or obstruction, may also arise, albeit through complex mechanisms. Despite these concerns, the benefits of pre-pubertal castration in managing overpopulation and reproductive diseases outweigh the risks. With vigilant veterinary care and post-operative management, adverse effects can be mitigated, underscoring the importance of this practice in controlling stray cat populations.

Влияние феминизирующей заместительной гормональной терапии на риски онкологических заболеваний, венозной тромбоэмболии и остеопении: Систематический обзор

Hormone replacement therapy (HRT) is a standard approach to medical care for patients with gender incongruence. HRT is aimed at suppression of primary and secondary sex characteristics of the sex assigned at birth and development of characteristics of the desired sex. HRT in trans women (TW) usually consists of estrogen preparations and antiandrogens. Epidemiological studies demonstrate that HRT reduces gender dysphoria, improves psycho-social outcomes and health-related quality of life. However, concerns about safety of this therapy are widespread both among patients and doctors. The systematic review seeks to elucidate the impact of feminizing HRT on risks of cancer, venous thromboembolism (VTE) and osteopenia among TW. Systematic search in Web of Science, Scopus and PubMed with keywords: “transgender” OR “transsexual” OR “gender dysphoria”, as well as “cancer”; “thromboembolism” OR “thromboembolic”; “osteoporosis” OR “bone”. Results: (a) Feminizing HRT does not enhance risks of cancer among TW. Slight increase in cancer prevalence can probably be attributed to lifestyle factors, especially smoking. (b) Modern schemes of feminizing HRT that do not contain ethinylestradiol are safe with regards to VTE. There's not enough data to understand the relationship between progestines and VTE risks. Continuation of HRT during the perioperative period probably does not increase risks of VTE during and after the surgery. (c) Results for impact of feminizing HRT on bone health are mixed. Suppression of androgens without replacement with estrogens clearly reduces bone mineral density (BMD) both among adults and adolescents.

Magnetic Resonance Imaging Findings in Mayer- Rokitansky-Küster-Hauser (MRKH) Syndrome: A Report of Two Cases

Introduction: Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome is a kind of Müllerian duct anomaly characterized by the absence or underdevelopment of the uterus and the top two-thirds of the vagina. MRKH syndrome is characterized by primary amenorrhea in young women who exhibit typical development of secondary sexual characteristics and normal external genitalia. These individuals have normal and functioning ovaries and a karyotype of 46, XX. Gonadal dysgenesis is the most prevalent cause of primary amenorrhea, followed by this condition. This case report aims to elaborate on MRI findings in females with typical and atypical types of MRKH syndrome. Case Description: The authors describe two female patients who presented with primary amenorrhea, normal external genitalia, and typical secondary sexual characteristics. These patients underwent MRI to identify the uterine and vaginal structure and additional non-gynaecologic abnormalities. Conclusion: MRI is the best imaging technique for the accurate evaluation of pelvic anatomy, uterine aplasia, uterine development, vaginal structure, and location of the ovaries, hence essential in the diagnosis, classification, and surgical planning of MRKH syndrome.

A revision of the millipede family Paracortinidae (Diplopoda, Callipodida).

The taxonomy of the family Paracortinidae Wang & Zhang, 1993 is revised based on literature, old and recently collected material. A new genus Crassipetalum Akkari & Stoev, gen. nov. is described, to accommodate a new species Crassipetalummagnum Akkari & Stoev, gen. nov. et sp. nov. and a recently described species Crassipetaluminflatum (Chen, Zheng & Jian, 2023), comb. nov. The genus Scotopetalum Shear, 2000 hitherto described for the Vietnamese species S.warreni Shear, 2000 and subsequently synonymised with the genus Paracortina Wang & Zhang, 1993 is here resurrected and supplemented with another species, S.chinensis (Stoev & Geoffroy, 2004), comb. nov., ex Paracortinachinensis Stoev & Geoffroy, 2004. The status of the fourth genus in the family, Angulifemur Zhang, 1997, is reconfirmed. Based on recently collected specimens from China, two new species of the genus Paracortina are described: P.asciformis Akkari & Stoev, sp. nov. (Sichuan Prov., Lixian County) and P.kabaki Akkari & Stoev, sp. nov. (Yunnan, Shangrila County). The Vietnamese species Paracortinamultisegmentata Stoev & Geoffroy, 2004 and Paracortinakyrang Nguyen, Stoev, Nguyen & Vu, 2023 are considered of uncertain taxonomic position within Paracortinidae. Differential diagnoses for the proposed genera as well as for all the species are presented, and descriptions or descriptive notes for all the species are provided, using a standardised terminology, and when possible, accompanied by micrographs of the habitus and gonopod structures. An identification key based on gonopod structures is proposed for all the members of the family. A discussion on species affinities, secondary sexual characters, troglomorphic characters, geographical distribution, and habitat preferences are also provided together with a distribution map for all members of the family.