Amblysomus septentrionalis (Roberts, 1913)

Russell A. Mittermeier & Don E. Wilson, 2018, Chrysochloridae, Handbook of the Mammals of the World – Volume 8 Insectivores, Sloths and Colugos, Barcelona: Lynx Edicions, pp. 180-203 : 196

3.

Highveld Golden Mole

Amblysomus septentrionalis

French: Taupe-dorée du Highveld / German: Highveld-Goldmull / Spanish: Topo dorado del Alto Veld

Taxonomy. Amblysomus corriae septentrionalis Roberts, 1913 ,

“Wakkerstroom,” Mpumalanga, South Africa .

Amblysomus septentrionalis traditionally was recognized as a subspecies of A. iris (now incorporated into A. hottentotus and A. corriae ). It was raised to full species by G. N.

Bronner in 1996 based on unique chromosomal number among chrysochlorids and distinct craniometric properties from sister species A. hottentotus and A. robustus . Monotypic.

Distribution. E South Africa, known from Barberton, Ermelo, and Wakkerstroom areas of Mpumalanga Province and Heilbron, Parys, and Harrismith of NE Free State, and Swaziland (Piggs Peak and Mbabane).

Descriptive notes. Head-body 114-135 mm (males) and 105-145 mm (females), hindfoot 13-20 mm (males) and 12-17 mm (females); weight 52-86 g. The Highveld Golden Mole is medium-sized and second largest species of Amblysomus . It has pronounced sexual dimorphism, with males on average larger than females. Size and pelage are similar to the Robust Golden Mole (A. robustus ) and the Drakensberg Golden Mole (A. longiceps). Pelage of the Highveld Golden Mole is dark reddish brown dorsally, lighter on flanks, and pale brown to orange ventrally. Pale yellow cheek patches extend laterally to subdermal eyes. Skull is elongated, zygomatic arches lack broad plates sweeping backward, mallei of inner ears are relatively small and unspecialized, and bullae are not externally evident. M? are absent, molar talonids are well developed, and P1 are sectorial (bicuspid) rather than molariform (tricuspid). Claws on forefeet are well developed but less robust than those of the Robust Golden Mole; claw on third digit is largest. Chromosomal complement has 2n = 34 and FN = 62.

Habitat. Mainly grasslands and edges of marshes in high-elevation southern African savanna only in Moist Sandy Highveld Grassland and Wet Cold Highveld Grassland biomes at elevations of ¢.1600-1800 m. Highveld Golden Moles can be common in well-irrigated farmlands, gardens, and golf courses and apparently at lower densities in exotic plantations. They are found in thickets of oldwood trees ( Leucosidea sericea, Rosaceae ) on banks of streams in valleys but avoid scrubby vegetation in kloofs (steep-sided, wooded ravine) and along rocky ridges, where Sclater’s Golden Mole ( Chlorotalpa sclateri ) predominates. Highveld Golden Moles are generally restricted to friable soils in valleys and on mountainsides, where they can occur in sympatry with Rough-haired Golden Moles ( Chrysospalax villosa).

Food and Feeding. The Highveld Golden Mole is insectivorous, feeding mainly on subterranean invertebrates, particularly earthworms and pupae.

Breeding. Highveld Golden Moles breed throughout the year but mainly in wet summer months (November-March), and they have 1-2 young/litter. Young are altricial at birth and raised in grass-lined nests in deep nesting chambers.

Activity patterns. Highveld Golden Moles construct two-tiered burrow system, with subsurface foraging tunnels and deeper (15-30 cm) tunnels leading to latrines and grass-lined nesting chambers. They are predominantly nocturnal, with activity declining rapidly at dawn and leading to daily torpor until late afternoon. Subsurface activity peaks in wet summer months (November—-March) and declines substantially in dry winter months (May—August).

Movements, Home range and Social organization. Adult Highveld Golden Moles appear to be solitary. They can be locally common; trapping data suggest densities of 3 ind/ha at one locality in the Wakkerstroom district.

Status and Conservation. Classified as Near Threatened on The IUCN Red List. The Highveld Golden Mole is currently known from twelve localities, with an estimated area of occupancy of only 2500 km?. It has not been found in any provincial or national nature reserves. Based on current estimates of area of occupancy, global population is over 10,000 individuals, although it appears to be declining. Inferred major threats include habitat degradation associated with mining for shallow coal deposits to fuel power stations in its high-elevation grassland habitats. Rehabilitation attempts at these sites have not been successful. Farming and agroforestry (exotic pine and eucalypt plantations) have also affected habitat but do not appear to pose a major threat. Predation by domestic pets and persecution by gardeners and greenkeepers could be localized threats. Research is currently underway to acquire data on distributional limits. Additional data are needed to understand densities, ecology, behavior, and reproduction of the Highveld Golden Mole.

Bibliography. Bernard et al. (1994), Bronner (1995a, 1996, 2000, 2013b), Mynhardt et al. (2015), Rampartab (2015b), Roberts (1951).

Figures

0. Yellow Golden Mole (Calcochloris obtusirostris), 1. Hottentot Golden Mole (Amblysomus hottentotus), 2. Robust Golden Mole (Amblysomus robustus), 3. Highveld Golden Mole (Amblysomus septentrionalis), 4. Marley’s Golden Mole (Amblysomus marleyi), 5. Fynbos Golden Mole (Amblysomus corriae), 7. Congo Golden Mole (Huetia leucorhina), 8. Somali Golden Mole (Huetia tytonis), 9. Gunning’s Golden Mole (Neamblysomus gunningi), 10. Juliana’s Golden Mole (Neamblysomus julianae), 11. Arend’s Golden Mole (Carpitalpa arendsi), 12. Sclater’s Golden Mole (Chlorotalpa sclateri), 13. Duthie’s Golden Mole (Chlorotalpa duthieae), 14. Stuhlmann’s Golden Mole (Chrysochloris stuhlmanni), 15. Cape Golden Mole (Chrysochloris asiatica), 16. Visagie’s Golden Mole (Chrysochloris visagier), 17. Rough-haired Golden Mole (Chrysospalax villosa), 18. Giant Golden Mole (Chrysospalax trevelyani), 19. De Winton’s Golden Mole (Cryptochloris wintoni), 20. Van Zyl's Golden Mole (Cryptochloris zyli), 21. Grant's Golden Mole (Eremitalpa grant)

Distribution. E South Africa, known from Barberton, Ermelo, and Wakkerstroom areas of Mpumalanga Province and Heilbron, Parys, and Harrismith of NE Free State, and Swaziland (Piggs Peak and Mbabane).