Intestinal helminths of four species of skinks (Mabuya) (Sauria: Scincidae) from southern Africa

Intestinal helminths are reported from four species of scincid lizards from southern Africa: Mabuya occidentalis, Mabuya spilogaster, Mabuya striata and Mabuya variegata. The helminth fauna consisted of one species of Cestoda, Oochoristica truncata and five species of Nematoda, Abbreviata paradoxa, Maxvachonia dimorpha, Parapharyngodon rotundatus, Spauligodon petersi and Thubunaea fitzsimonsi. All findings represent new host records. Ascarid larvae were also found. It appears that Mabuya is infected by generalist helminths that occur in other species of African lizards.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat v.9 was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

Helminths in

Entomelas duellmani n. sp. (Rhabditida: Rhabdiasidae) from the lungs and Skrjabinodon cartagoensis n. sp. (Oxyurida: Pharyngodonidae) from the intestines of Mesaspis monticola (Sauria: Anguidae) are described and illustrated. E. duellmani is the sixth species assigned to the genus and is the third species described from the Western Hemisphere. It is easily separated from other neotropical species in the genus by pre-equatorial position of its vulva. Skrjabinodon cartagoensis is the 24th species assigned to the genus and differs from other neotropical species in the genus by female tail morphology

The coordination of heart and gill rhythms in \u3cem\u3eLimulus\u3c/em\u3e

WhenLimulus is exposed to hypoxia both heart rate and ventilation rate decrease together (Fig. 1, Fig. 2A). Hypoxia ultimately leads to cessation of ventilation and concomitant bradycardia. When oxygen is reintroduced into an oxygen free aquarium ventilation resumes rapidly, with a parallel increase in heart rate (Fig. 1, Fig. 2B). Covariation of heart and gill activity similar to that in hypoxia experiments also occurs during the normal respiratory behavior patterns ofLimulus, such as intermittent ventilation, swimming, hyperventilation and gill cleaning. The covariation of heart and ventilation rates is especially evident during transitions of intermittent ventilation (alternating periods of apnea and ventilation, Fig. 3). Covariation is also evident during the large increases in ventilation frequency which occur during hyperventilation and swimming (Fig. 4). Gill cleaning is a centrally determined motor sequence which consists of rhythmic flicking of the inner lobes of a gill plate between the book gill lamellae of the plate on the opposite side. During this behavior there is a marked slowing of the heart rate which is at least as great as the decrease in rate seen during periods of apnea (Figs. 5 and 6). Changes in heart rate associated with ventilatory activity do not appear to be caused by the metabolic demand resulting from such activity (Fig. 7). In addition to frequency covariation of the heart and ventilation rates, there can also be phase coordination of the two rhythms. When the two are close to the same frequency or to harmonic frequencies, the heart often maintains a phase preference with respect to the concurrent gill interval over a considerable period of time (Fig. 8). These results suggest that there are common tonic inputs to both the cardiac ganglion and the central pattern generators for the various ventilatory behaviors, which modulate the frequencies of both simultaneously. Both the frequency covariation and phase communication between the two systems may serve to increase the efficiency of the respiratory-circulatory interactions