The genus Helicotylenchus in the grassland biome of South Africa

The genus Helicotylenchus is widespread in South Africa with 25 of the 33 Helicotylenchus species in the grassland biome. With 23 species reported from uncultivated areas, 14 species from crop plants and 10 species from the grasses grown on sports fields, Helicotylenchus is ideally suited for a study on the impact of cultivation on nematode diversity.This paper was initially delivered at the Annual Congress of the Biological Sciences Division of the South African Academy for Science and Art, ARC-Plant Protection Research Institute, Roodeplaat, Pretoria, South Africa on 01 October 2010.http://www.satnt.ac.zaam2014ab201

Global Retinoblastoma Presentation and Analysis by National Income Level

Importance: Early diagnosis of retinoblastoma, the most common intraocular cancer, can save both a child's life and vision. However, anecdotal evidence suggests that many children across the world are diagnosed late. To our knowledge, the clinical presentation of retinoblastoma has never been assessed on a global scale. Objectives: To report the retinoblastoma stage at diagnosis in patients across the world during a single year, to investigate associations between clinical variables and national income level, and to investigate risk factors for advanced disease at diagnosis. Design, Setting, and Participants: A total of 278 retinoblastoma treatment centers were recruited from June 2017 through December 2018 to participate in a cross-sectional analysis of treatment-naive patients with retinoblastoma who were diagnosed in 2017. Main Outcomes and Measures: Age at presentation, proportion of familial history of retinoblastoma, and tumor stage and metastasis. Results: The cohort included 4351 new patients from 153 countries; the median age at diagnosis was 30.5 (interquartile range, 18.3-45.9) months, and 1976 patients (45.4) were female. Most patients (n = 3685 84.7%) were from low-and middle-income countries (LMICs). Globally, the most common indication for referral was leukocoria (n = 2638 62.8%), followed by strabismus (n = 429 10.2%) and proptosis (n = 309 7.4%). Patients from high-income countries (HICs) were diagnosed at a median age of 14.1 months, with 656 of 666 (98.5%) patients having intraocular retinoblastoma and 2 (0.3%) having metastasis. Patients from low-income countries were diagnosed at a median age of 30.5 months, with 256 of 521 (49.1%) having extraocular retinoblastoma and 94 of 498 (18.9%) having metastasis. Lower national income level was associated with older presentation age, higher proportion of locally advanced disease and distant metastasis, and smaller proportion of familial history of retinoblastoma. Advanced disease at diagnosis was more common in LMICs even after adjusting for age (odds ratio for low-income countries vs upper-middle-income countries and HICs, 17.92 95% CI, 12.94-24.80, and for lower-middle-income countries vs upper-middle-income countries and HICs, 5.74 95% CI, 4.30-7.68). Conclusions and Relevance: This study is estimated to have included more than half of all new retinoblastoma cases worldwide in 2017. Children from LMICs, where the main global retinoblastoma burden lies, presented at an older age with more advanced disease and demonstrated a smaller proportion of familial history of retinoblastoma, likely because many do not reach a childbearing age. Given that retinoblastoma is curable, these data are concerning and mandate intervention at national and international levels. Further studies are needed to investigate factors, other than age at presentation, that may be associated with advanced disease in LMICs. © 2020 American Medical Association. All rights reserved

A check list of the pseudoscorpions of South Africa (Arachnida: Pseudoscorpiones)

A check list of the Pseudoscorpiones of the class Arachnida of South Africa is presented. A total of 135 species and 10 subspecies of pseudoscorpions are known from South Africa, represented by seven superfamilies, 15 families and 65 genera. This represents about 4.4 of the world fauna. Of the 135 species, 97 species (73 ) are known only from South Africa, 33 species have a wider distribution pattern throughout the Afrotropical Region and three are cosmopolitan. This study forms part of the South African National Survey of Arachnida (SANSA)

Revision of the Afrotropical crab-spider genus Parabomis Kulczyński, 1901 (Araneae: Thomisidae)

The Afrotropical spider genus Parabomis Kulczyński, 1901 is revised. Members of Parabomis are some of the smallest thomisids known, and occur from Eritrea in the north of Africa to South Africa in the south, but are absent from Madagascar. Prior to this study, three species were known, namely P. levanderi Kulczyński, 1901 (Eritrea, ♂), P. martini Lessert, 1919 (Tanzania, ♂♀) and P. anabensis Lawrence, 1928 (Namibia, ♀). Parabomis anabensis sp. nov. is here recognized as a junior synonym of P. martini and four new species are described: P. elsae sp. nov. from South Africa (♂♀), P. megae sp. nov. from Zimbabwe (♂♀), P. pilosus sp. nov. from Botswana (♂♀) and P. wandae sp. nov. from Ghana (♂♀). A key to the six species is provided. The monotypic Afrotropical genus Felsina Simon, 1895, only known from its type species, F. granulum Simon, 1895, resembles Parabomis closely is known only from juveniles

New records of Cladomelea from South Africa, including the first records of C. longipes (O. Pickard-Cambridge, 1877) (Araneae, Araneidae) outside its type locality

We present the first records of the bolas spider, Cladomelea longipes (O. Pickard-Cambridge, 1877), beyond its type locality, resulting in a considerable extension of its geographic range in Africa. We compare C. longipes with the two other species of Cladomelea known from South Africa, C. akermani Hewitt, 1923 and C. debeeri Roff & Dippenaar-Schoeman, 2004. Images of live specimens and a distribution map are provided. Cladomelea longipes is very rare locally but has a relatively large geographical distribution in the Afrotropical Region

The effect of elevation and time on mountain spider diversity: a view of two aspects in the Cederberg mountains of South Africa

Aim Our aim is to test if long-term patterns in α alpha and ß beta diversity along an elevational transect on two aspects of a mountain are consistent through time using spiders as model organisms, quantify the role of elevation and time (seasonal and inter-annual) in explaining these patterns and partition the relative contribution of nestedness, species turnover and species loss in explaining these diversity patterns. Location The transect is across the Cederberg mountains in the Cape Floristic Kingdom, Western Cape, South Africa and is constituted by 17 sites with an elevational range of 1900 m on two aspects of the mountain (east and west). Methods Spider assemblages were sampled biannually (wet and dry seasons) over 6 years. Four replicates per site, each consisting of a 5 x 2 pitfall grid, were sampled for 5 days sessions. Generalized linear mixed models with Poisson error structure for species richness (alpha diversity), binomial error structure for beta diversity (Jaccard dissimilarity ßcc and its partitioned components, ß-3 and ßrich), and Gaussian error structure for beta diversity values standardized by a null model (SES) were used to model the effects of elevation and season on these two indices respectively. Results Although varying considerably between years, spider alpha diversity had a hump-shaped pattern on the western aspect and U-shaped on the eastern aspect. However, season interacted with elevation to produce more complex patterns during the dry season. There was no significant nestedness except for two instances on the western aspect. Replacement accounted for 60–70% of beta diversity between sites, and elevational distance decay in beta diversity was the result of increased turnover on the western aspect and increased species loss on the eastern aspect. Standardized patterns suggest that there are no effects of season on beta diversity except for a decreased distance decay during the dry season on the western aspect. Main conclusions Large-scale predictors of spider alpha diversity explained small amounts of variation in spider diversity, pointing to the importance of local and stochastic processes. Regional turnover of spider diversity is mainly the result of niche processes, suggesting localized adaptation of taxa, further supported by the lack of nestedness in assemblages

Aseasonal reproduction in the Hottentot golden mole, Amblysomus hottentotus (Afrosoricida: Chrysochloridae) from KwaZulu-Natal, South Africa

The Hottentot golden mole, Amblysomus hottentotus, is a subterranean mammal that exhibits aseasonal breeding. Reproductive organs of golden moles that had been killed on a monthly basis over a period of one year were examined. Reproductive tract measurements and body mass of each individual was measured and ovarian and testicular histology investigated. Body mass of males was significantly higher than that of females. Ovarian and testicular volume as well as seminiferous tubule diameter did not vary statistically on a seasonal basis. Graafian follicles and corpora lutea were present in the ovaries for nine months of the year, suggesting that ovulation can occur in any month. Despite the lack of seasonality, there appears to be enhanced follicular development during the warm, wet summer months. The litters tend to be small, mean ± S.E.: 2.0 ± 0.1 (range 1.0–3.0).Keywords: reproductive organs, histology, body mass, litter siz