The forest batis, Batis mixta, is two species: description of a new, narrowly distributed Batis species in the Eastern Arc biodiversity hotspot

The forest batis, Batis mixta, is a common bird of the forests of the Eastern Arc Mountains of Tanzania and in some adjacent montane and coastal forests. Through new collecting efforts in most of this range we documented a well-marked change in morphology in the middle of the range. Supplementary genetic studies of the historical population structure suggest connectivity among the south-western and northern/coastal populations, but not between these parapatric groups. It is concluded that two species are involved, and a new name B. crypta is proposed for the south-western populations. A marked genetic break also exists towards B. capensis sola in northern Malawi. The morphologically distinctive form reichenowi in south-eastern Tanzania is genetically nested within B. mixta, and for now we keep it as a subspecies of B. mixta.     

Lo Sviluppo Del Sistema Conduttore Di “Ginkgo Biloba” L.

Bupleurum gracile (M. Bieb.) DC. var. rollii Montel. ( ≡ Bupleurum rollii [Montel.] Moraldo) is lectotypified on a herbarium specimen kept in RO, revising the previous typification by S. Snogerup and B. Snogerup. An isolectotypes and 14 syntypes are also selected. Infraspecific variability and comparison with related Eastern species B. asperuloides Heldr. B. uechtritzianum S. Stoyanov and B. marschallianum C. A. Mey plus B. gracile D'Urv. are studied using morphometric and anatomical data. Notes on the ecology and distribution of the Italian endemic taxon are also provided.     

Seasonality and host utilization of the invasive fruit fly, Bactrocera invadens (Dipt., Tephritidae) in central Tanzania

Abstract:  The temporal occurrence of the invasive and economically important pest fruit fly, Bactrocera invadens was studied in three agro-ecological areas of Morogoro Region, central Tanzania, during 2004–2005. Weekly and monthly trappings were carried out with methyl eugenol, protein bait and synthetic food attractant. Bactrocera invadens was permanently present at low and mid-altitudes (380–520 m a.s.l.) with peak periods coinciding with the fruiting season of mango ( Mangifera indica ) and guava ( Psidium guajava ). At high altitude (1650 m a.s.l.) its incidence was only temporal and apparently the result of dispersal from lower altitudes after the mango fruiting season. Rearing results showed mango, loquat ( Eriobotrya japonica ), guava and grapefruit ( Citrus  ×  paradisi ) to be the favoured commercial host fruits. Other Citrus species, cucurbits, papaya ( Carica papaya ) and avocado ( Persea americana ) were less favoured.     

Coleopteran diversity and abundance in different habitats near Kihansi waterfall, in the Udzungwa Mountains, Tanzania

Coleoptera diversity at the family level was investigated along the Kihansi gorge near a 700 m high waterfall system which will be taken to hydropower use, and the current river flow will be diverted due to dam construction. The coleopteran communities of three micro-habitats: spray zone, forest site and riverine site were compared by sweepnetting and pitfall trap methods. The highest Coleopteran family level diversity was found in the spray zone where the Shannon–Weaver index of diversity was 0.71 (forest site 0.31; riverine site 0.50). Coleopterans were most abundant in the forest site where 44% of all sampled individuals were found (spray zone 31%; riverine site 23%). Most of less frequently recorded families were found in the spray zone. Coleoptera families were found to be unequally partitioned in all three micro-habitats. The highest percentage similarity index (85%) was found between forest and riverine sites (spray/forest 76%; spray/riverine 79%). Distributions of abundances of coleopteran families were significantly different between all studied habitats. The study revealed that the spray generated by the waterfall provide a special micro-habitat for Coleoptera. It is suggested that conservation efforts and monitoring in the study area using selected taxonomic indicator Coleopteran groups should be carried out in order to help to adjust mitigation measures.     

Monkey Abundance and Social Structure in Two High-Elevation Forest Reserves in the Udzungwa Mountains of Tanzania

The effects of human activity on population and social structure are a pantropical concern for primate conservation. We compare census data and social group counts from two forests in the Udzungwa Mountains, Tanzania. The main aim is to relate differences within and between the forests to current theory on the effect of human disturbance on primate abundance and group size. The survey reveals the presence of the restricted-range red colobus, Procolobus gordonorum, in New Dabaga/Ulangambi Forest Reserve (NDUFR). The primate community of NDUFR is impoverished compared to that in Ndundulu forest. Red colobus and black-and-white colobus (Colobus angolensis palliatus) abundance and group size are lowest in NDUFR. Fission-fusion of red colobus social groups may be occurring in previously logged areas of both forests. Our observations are consistent with current theory on the effect of habitat degradation and hunting on primates, but the relative effects of the 2 factors could not be differentiated. We pooled the results with previous data to show that abundance of red colobus in the Udzungwa Mountains is lowest at high elevations. Low red colobus group sizes appear to be related to human activity rather than elevation. Black-and-white colobus and Sykes monkeys (Cercopithecus mitis) show no relationship with elevation. Future studies will require more detailed information on vegetation, diet and ranging patterns to interpret fully intraspecific variation in population demography and social structure in the Udzungwa Mountains.     

Amphibian Diversity in East African Biodiversity Hotspots: Altitudinal and latitudinal Patterns

The Eastern Arc mountain chain and adjoining coastal forests of Tanzania and Kenya have been listed as world biodiversity hotspots. We report on an ongoing attempt to estimate amphibian diversity on the three best studied mountains of the Eastern Arc, the East Usambara, Uluguru and Udzungwa mountains of Tanzania, complemented by an estimate of diversity on the adjoining coastal lowland. This proves to be a complex task, which introduces a note of caution into evaluating global biodiversity estimates. Most amphibian species in eastern Tanzania occur on the coastal lowlands and are widely distributed, extending at least north or south of Tanzania and, to a variable extent, westwards to the elevated interior. Diversity patterns along the length of the lowlands are complex, with the presence of a Sahelian element in the extreme north. On the three Eastern Arc mountains studied, species turnover associated with rising altitude is greater than turnover associated with latitudinal distance between the mountain blocks, leading to greater altitudinal than latitudinal diversity in this equatorial region. A long-standing divergence is indicated between montane and lowland endemics. Although forest-associated species are not the largest contributor to the eastern Tanzanian total species diversity (some 48%), the uniqueness of these species both in lowland and montane forests, combined with their evident vulnerability to disturbance, makes them a subject for particular conservation concern, and justifies hotspot status for both montane and lowland forests.