Butterflies (Lepidoptera: Papilionoidea) of Mount Kilimanjaro: Nymphalidae subfamilies Libytheinae,Danainae, Satyrinae and Charaxinae

This paper, which presents an annotated checklist of the ‘lower Nymphalidae’ (Libytheinae, Danainae, Satyrinae, Charaxinae), is the fourth in a series on the butterfly fauna of Mount Kilimanjaro. Four genera of lower Nymphalidae (Danaus, Amauris, Bicyclus, Charaxes), with a total of 11 included species, are known or believed to occur within the main forest zone, from c. 1800 to 2800 m. Of these, only three species of Charaxes (Charaxes berkeleyi, Charaxes ansorgei, Charaxes xiphares) may be restricted locally to this primary forest. The lower slopes fauna, below 1800 m, is considerably richer, with a total of 11 genera and 41 species listed (8 species of which extend into the forest zone). Possible additional species, dubious earlier records, problems with African subspecies of Danaus chrysippus, a need for more work on certain Satyrinae, and classification of the genus Charaxes are discussed. An identification key to the subfamilies of Nymphalidae, and the 19 genera of Libytheinae, Danainae, Satyrinae, Charaxinae that occur in Tanzania, together with a key to the adults of all the species of these four subfamilies considered to occur or have occurred on Kilimanjaro, with 206 colour images, are included as online Supplementary Information.     

Eustigmaeus floridensis sp. nov., a new mite species of the genus Eustigmaeus Berlese, 1910 (Acari: Stigmaeidae) from citrus in Florida

Eustigmaeus floridensis sp. nov. is described and illustrated based on female specimens collected from citrus trees in Florida, USA. The new species is closely related to Eustigmaeus arcuata, Eustigmaeus segnis and Eustigmaeus microsegnis, all known to occur in Florida. Eustigmaeus floridensis sp. nov. can be distinguished by larger dimples associated with setae sce, d₂ and e₁ containing at least four or more vacuoles centrally; dorsal body setae broadly lanceolate and feather-like, except c₂, which is slender; anogenital area with striae and one pair of serrated aggenital (ag1) and three pairs of serrated pseudanal (ps_1?3) setae. A key to the Eustigmaeus species known to occur across USA is also provided.     

Baronia brevicornis caterpillars build shelters to avoid predation

In at least 18 Lepidoptera families, caterpillars build shelters that mainly serve to regulate microclimate (humidity, temperature) and/or to avoid predation. We aimed to explore the function of the tubular structures built with the leaves of the host plant, Acacia cochliacantha Humboldt and Bonpland ex Willdenow (Fabaceae), by a lepidopteran endemic to Mexico, Baronia brevicornis Salvin. We experimentally evaluated whether tubular structure building behaviour is induced by high temperature or predator odour, and if shelters reduce or enhance predation of B. brevicornis caterpillars. We used Calosoma angulatum as predator. Our analyses showed that caterpillars did not make the tubular structures in response to high temperature. We also found no difference in predators’ visual recognition of sheltered versus unsheltered caterpillars. Caterpillars did not build shelters but they moved more often when exposed to predator odour. Unsheltered caterpillars were more frequently consumed when predators were allowed to interact with sheltered and unsheltered caterpillars. Hence, the tubular structures built by B. brevicornis are most likely a strategy for reducing predation, for example by C. angulatum.     

Swimming and bipedal bottom-running in the pig-nosed turtle Carettochelys insculpta Ramsay, 1886

The pig-nosed freshwater turtle Carettochelys insculpta Ramsay, 1886 has paddle-shaped foreflippers that resemble those of sea turtles. These turtles exhibit a wide range of swimming capabilities. As well as swimming by the action of synchronized foreflippers alone, they sometimes used alternate hindlimb action at the same time. They could swim by ipsilaterally synchronized action of all four limbs, or by hindlimb action alone (combined with stabilizer/lift function of the foreflippers). The turtles also showed flexibility in bottom-walking. Besides the ipsilaterally synchronized quadrupedal action characteristic of other freshwater turtles, they exhibited a bipedal walking mechanism never previously described. Propelled by alternate action of the hindlimbs, the animals held the head and plastron above the substratum, with the large foreflippers acting to provide anterior lift and stability against roll and yaw. Because both hindlimbs were sometimes off the substratum simultaneously during bipedal locomotion, their duty factors were < 0.5, implying a bipedal run.     

Diversity and dispersal history of the talitrids (Crustacea: Amphipoda: Talitridae) of Bermuda

Five taxa of talitrid amphipods were found in the archipelago of Bermuda, of which three were recorded there for the first time. Four of these are supralittoral wrack generalists: Platorchestia monodi BOLD:AAB3402, (a unique Molecular Operational Taxonomic Unit according to the Barcode Index Number system), a related species recognized by molecular methods, Platorchestia platensis BOLD:AAA2949, Mexorchestia carpenteri carpenteri BOLD:AAC1491 and Tethorchestia antillensis; and one a terrestrial leaf-litter generalist: Talitroides alluaudi. A key is provided to discriminate between the formally described talitrids of Bermuda. Dispersal mechanisms from the American continent to Bermuda were considered for all taxa based on species distributions along the North American Atlantic coast and also investigated by molecular methods, using genetic population differentiation and haplotype network analysis based on the barcode region of cytochrome c oxidase subunit I gene. For P. monodi BOLD:AAB3402 the genetic results suggest that some dispersal events occurred before human colonization of Bermuda but are equivocal about the source population and therefore the direction of dispersal. Some very recent synanthropic dispersal is possible with this species. For the other two species studied genetically, P. platensis BOLD:AAA2949 and M. c. carpenteri BOLD:AAC1491, the small population samples analysed support dispersal to Bermuda from the American mainland, before human occupation of Bermuda, although the available sample size was limited for these species. The available limited direct, non-genetic evidence supports synanthropic transport for Talitroides alluaudi. Platorchestia monodi BOLD:AAB3402 is found in the same wrack habitat as P. platensis BOLD:AAA2949 on Bermuda, apparently without interbreeding. No evidence was found that driftwood specialist talitrids had become established in Bermuda.     

New insights on the external features of egg capsules and embryo development in the squid Loligo vulgaris

The embryonic development of the squid Loligo vulgaris was observed from 183 egg masses collected from special devices deployed throughout Cabrera National Park (Baleares Islands, western Mediterranean Sea). Sequence alignment analysis of the cytochrome oxidase I gene revealed that all embryos belonged to L. vulgaris. In total, 549 egg capsules were examined. Viable egg capsules (n = 420) were classified into one of five maturation stages according to the primary external features. The length of the viable egg capsules varied between 40 and 170 mm, and increased with embryonic development. The non-viable capsules (n = 129) were categorized into four groups: I (Ginger root), non-viable II and III, and empty egg capsule (IV). The percentage of non-viable capsules (i.e. grades I, II and III) was 92.25%. Empty capsules accounted for 7.75% of the total non-viable egg capsules. Embryonic development was classified into a second scale of eight stages. Egg capsule stage and embryonic stage were significantly related (n = 420; p < 0.001), facilitating the determination of the embryo developmental phase based on the outward appearance of the egg capsules. The embryo development stage based on the external features of the egg capsules might constitute an innovative tool for in situ embryological data collection. This new method is neither time consuming nor invasive, and could be helpful in fishing cruises, for scuba diving visual census in natural habitats and for laboratory culture. Slight variability in the developmental embryonic stages within egg capsules from the same egg mass was identified. The origin of this asynchrony is discussed. Chronological appearance of organs was similar to that of the six loliginid species previously examined. However, some developmental changes in the timing or rate of events (heterochronies) were observed: Hoyle’s organ was formed earlier in L. vulgaris and the appearance of ventral chromatophores was slightly delayed (2 days) compared with the other species considered.