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Monanema joopi n. sp. is described from blood drawn from the heart of the murid Acomys (Acomys) spinosissimus in South Africa. It is characterised by a non-bulbous cephalic extremity, shared with only one of its five congeners, and a cylindrical tail with caudal alae and a spicular ratio of 2.7 in the male. As is typical for the genus, microfilariae are skin-dwelling. They are 185 to 215 micrometres long and have no refractory granules beneath their sheath. A key to the species of Monanema is presented and an amended generic description, based on the six currently known species, is proposed. Species of Monanema are primarily lymphatic and the low intensity of infection with M. joopi n. sp. in blood from the heart, might suggest that not all adults settle in the heart cavities. One might also consider that other, more susceptible rodents serve as hosts for this parasite as well. To date, the geographic range of Monanema includes North America, Africa and Australia, each with representatives of a different lineage. Given the present hypotheses on the evolutionary origin and subsequent migrations of rodents, we expect the origin of Monanema to be in the Palearctic-Oriental region.

The naked mole-rat ( Heterocephalus glaber ) and the Damaraland mole-rat ( Fukomys damarensis ) live in large colonies in underground tunnel systems in sub-Saharan Africa. Most members of the colonies are suppressed from reproduction and they are unlikely to reproduce during their lifetime. Only one female and a small number of males reproduce. This extreme cooperative social system has fascinated researchers since the naked mole-rat was first described as eusocial. Despite much research into the mechanisms of social suppression, the exact mechanisms are still unclear. Much evidence points towards high glucocorticoid concentrations caused by agonistic behaviour by the breeding female suppressing reproduction of non-breeders, but laboratory studies have not found any differences in glucocorticoids between breeders and non-breeders. There is, however, considerable evidence from field studies and other social mole-rats that social stress may indeed be an important factor of social suppression in social mole-rats and that those mechanisms are affected by the stability of the colony and environmental conditions. This review aims to provide a summary of the current knowledge of the relationship between environmental conditions, colony stability, glucocorticoids and reproductive suppression in social mole-rat species and suggests some avenues for future research.

The complex interaction between factors leading to amphibian declines is responsible for the inability to develop robust, standardized conservation action plans. Monitoring physiological stress responses in amphibians may provide an ideal tool to assist conservationists in this regard. This study aimed to validate dermal secretions as a robust matrix for monitoring glucocorticoid alterations in an African amphibian, the edible bullfrog ( Pyxicephalus edulis ). Both a biological (handling) and physiological (ACTH challenge) validation were conducted to determine which of five available enzyme immunoassays (EIAs) tested is most suited for monitoring alterations in dermal glucocorticoid (dGC) concentrations. Additionally, the most optimal body region for monitoring dGC concentrations in P. edulis was identified. To confirm the activation of the hypothalamic-pituitary-interrenal (HPI) axis following ACTH administration, urinary glucocorticoid metabolites (uGCM) were also quantified. The tested corticosterone EIA was the only assay able to monitor alterations in dGC concentrations following the handling event in P. edulis . Further validation during the ACTH challenge supported the corticosterone EIA in this regard. Dermal secretions collected from both the ventral and dorsal regions were suitable for monitoring dGC concentrations in both sexes. A considerable increase in uGCM concentrations following ACTH administration was found, suggesting that the dGC concentrations observed were derived from the HPI axis. This study offers further support for the use of dermal secretions as an important matrix for monitoring physiological stress, and thus general health, in amphibian species.

The first collection of unengorged and fully engorged larvae of Nuttalliella sp. (N. namaqua?) from the murid rodents Micaelamys namaquensis, Aethomys chrysophilus and Acomys spinosissimus in Limpopo Province and from M. namaquensis in the Northern Cape Province, South Africa, is documented. A total of nine larvae were collected from two M. namaquensis in the Soutpansberg mountain range in the Limpopo Province during April 2009. During the last week of September 2011, 221 larvae were collected from rodents at the same locality and 10 of 48 M. namaquensis, 6 of 12 Ae. chrysophilus and 3 of 14 Ac. spinosissimus were infested. One of the M. namaquensis harboured 53 larvae. Five larvae were collected from two M. namaquensis in the Northern Cape Province. Total genomic DNA was extracted from two larvae and a region of the 18S rRNA gene was sequenced for these. BLASTn searches revealed similarity between these specimens and the Nuttalliella sequences published on GenBank.

Many lizard species will shed their tail as a defensive response (e.g., to escape a putative predator or aggressive conspecific). This caudal autotomy incurs a number of costs as a result of loss of the tail itself, loss of resources (i.e., stored in the tail or due to the cost of regeneration), and altered behavior. Few studies have examined the metabolic costs of caudal autotomy. A previous study demonstrated that geckos can move faster after tail loss as a result of reduced weight or friction with the substrate; however, there are no data for the effects of caudal autotomy on locomotory energetics. We examined the effect of tail loss on locomotory costs in the Cape dwarf gecko Lygodactylus capensis ( approximately 0.9 g) using a novel method for collecting data on small lizards, a method previously used for arthropods. We measured CO(2) production during 5-10 min of exhaustive exercise (in response to stimulus) and during a 45-min recovery period. During exercise, we measured speed (for each meter moved) as well as total distance traveled. Contrary to our expectations, tailless geckos overall expended less effort in escape running, moving both slower and for a shorter distance, compared with when they were intact. Tailless geckos also exhibited lower excess CO(2) production (CO(2) production in excess of normal resting metabolic rate) during exercising. This may be due to reduced metabolically active tissue (tails represent 8.7% of their initial body mass). An alternative suggestion is that a change in energy substrate use may take place after tail loss. This is an intriguing finding that warrants future biochemical investigation before we can predict the relative costs of tail loss that lizards might experience under natural conditions.