The Status of Carex elongata (Cyperaceae) in Yorkshire

Gingerbread or Elongated Sedge Carex elongata L. is a rare plant in eastern England and the Yorkshire populations are isolated from the main distribution. It has only ever naturally occurred at five sites and is extant at two of them, one of which probably results from a recent colonisation event. It has been re-introduced near another of its historic sites. At its principal site, Askham Bog near York, the plant has expanded its population considerably over the last 40 years. Its local distribution appears to be strictly limited by topography and winter flooding. Its ability to colonise new sites and to expand populations show that earlier concern about seed viability was misplaced.

Parasitoid wasps indicate that the marsh fritillary butterfly (Euphydryas aurinia) has persisted on Tiree rather than re-colonised recently

The population of the marsh fritillary butterfly (Euphydryas aurinia) in western Scotland fluctuates greatly and the species is difficult to locate during periods of scarcity. It was recorded on Tiree in 2014 for the first time in 64 years during a period of abundance. The nearest known populations occur 40 km to the east and its discovery represents either a recent colonisation event well beyond its known capability or it has escaped detection for a longer period. Surveys for the larval cocoons of two wasps that are parasitoids of E. aurinia and host-specific were undertaken on Tiree in spring and autumn 2017. The adult wasps are small with limited powers of dispersal and are unlikely to have followed E. aurinia to Tiree since 2014. Cocoons of one species - Cotesia melitaearum – were abundant in all concentrations of E. aurinia in spring 2017 but neither species was found in the autumn. The absence of the second species - C. bignellii - is inconclusive as it was also absent at known locations elsewhere in autumn 2017. The occurrence, distribution and abundance of C. melitaearum on Tiree indicate that E. aurinia had been present for some time before its discovery in 2014. Although continuous presence since 1950 cannot be extrapolated with certainty, the results highlight the propensity of E. aurinia to persist for long periods in numbers that fall below the observation threshold, even in areas of high wildlife awareness, and that it is not always an easy species to record.

Status of the Northern Silvery Grebe Podiceps juninensis in the northern Andes: recent changes in distribution, population trends and conservation needs

SummaryThe Northern Silvery Grebe Podiceps juninensis is an aquatic bird species considered Vulnerable to extinction in Ecuador and Endangered in Colombia. Globally the species is considered Near Threatened. Herein we report recent changes in distribution and population trends for the subpopulation in the northern Andes (Ecuador, Colombia), which is small and isolated. The Northern Silvery Grebe has undergone two documented extirpations, and at least one colonisation event, over the last three decades. More than 90% of the subpopulation relies on two wetlands, La Mica and Colta lakes in Ecuador, with the latter facing an accelerated sedimentation process which jeopardizes the fate of the wetland, and the species, in the mid-term. The population of La Mica lost 80% of its birds in 2000 after the damming of the lake, but then remained stable over our census period (2004–2013). In contrast, the Colta population results from a recent colonisation in the early 2000s, and has experienced an exponential growth since then (annual population multiplication rate: 1.464). The growth of this population is so fast that it must include an important contribution of immigrants. The temporal coincidence between the drop in population size at lake La Mica and the colonisation of lake Colta suggests that the Colta population was founded by immigrants from La Mica. Finally, the absence of current reports of the species at wetlands in Colombia suggests that the species remains at very low numbers, bolstering the shrinkage in northern distribution.

Identification of the rainbowfish in Lake Eacham using DNA sequencing

The Lake Eacham rainbowfish (Melanotaenia eachamensis) was once thought to be confined to its type locality within the Lake Eacham World Heritage National Park. M. eachamensis disappeared from the lake following the translocation of several species into the lake and the species was pronounced extinct in the wild in 1987. In a 2007 survey we noticed that rainbowfish were present in the lake once again. We used a molecular marker to identify these fish and the likely source population. Analysis of the D-loop region of mitochondrial DNA revealed that the species now present in the lake is Melanotaenia splendida, and is most closely related to several M. splendida populations in the immediate vicinity. Here we explore a range of scenarios that may have led to this colonisation event and highlight the dangers associated with translocation.

Platynini (Coleoptera:Carabidae) of Vanuatu: Miocene diversification on the Melanesian Arc

Vanuatu supports 11 resident species of the carabid beetle tribe Platynini: five indigenous species shared with other Pacific islands and Australia and six newly described precinctive species. Notagonum delaruei, sp. nov. represents a single descendant species of one colonisation event. Helluocolpodes, gen. nov. (type species Colpodes helluo Darlington of New Guinea) is proposed to accommodate a monophylum comprising the type species plus Helluocolpodes discicollis, sp. nov., H. mucronis, sp. nov., H. multipunctatus, sp. nov., H. sinister, sp. nov. and H. vanemdeni, sp. nov., all from Vanuatu. Generic assignments are informed by cladistic analysis of anatomical characters for a variety of Pacific platynine taxa. Metacolpodes Jeannel is redefined cladistically to include seven Pacific and Asian species. Biogeographic relationships among island areas housing platynine taxa on the Australian and Pacific Plates are investigated using a chrono–area cladogram, i.e. a taxon–area cladogram for which terminals are dated based on geological evidence and internal nodes based on non-reversible temporal optimisation. Conclusions reached by constraining the ages of areas within the context of phylogenetic relationships of their resident taxa include: (1) Vanuatu has supported resident platynine taxa since the Middle to Late Miocene; (2) the Hawaiian Blackburnia first colonised that archipelago in the Miocene, long before the present oldest high island, Kauai, came into existence; (3) the New Zealand Ctenognathus most likely arose from Miocene colonisation of New Zealand via Fiji; and (4) the low diversity of the Tahitian platynine fauna is due to relatively recent, Pliocene or later, colonisation of the Society Island chain by this group, also from a Fijian source.

Dispersal of the moss Campylopus pyriformis on geothermal ground near the summits of Mount Erebus and Mount Melbourne, Victoria Land, Antarctica

Mount Melbourne in northern Victoria Land, Antarctica, is a glaciated 2733 m volcanic cone. The moss Compylopus pyriformis occurs on two small areas of steam-warmed snow-free ground near its summit. This moss species also occurs in temperate regions world-wide, but has not been recorded elsewhere in continental Antarctica. RAPD (Random Amplified Polymorphic DNA) studies of 26 samples of C. pyriformis from two areas of heated ground on Mount Melbourne showed there was genetic diversity within the population. Genetic evidence for dispersal between the two sites, together with some genetic variation within individual colonies, indicates a single colonisation event has probably occurred at this extremely isolated location followed by multiple mutations. A single sample of moss protonema was collected 25 years ago from steam-warmed ground near the summit of another volcano, Mount Erebus (3794 m), on Ross Island some 300 km south of Mount Melbourne. The moss could not be identified based on morphological and reproductive criteria, as all attempts to differentiate it to a recognisable gametophyte were unsuccessful. The RAPD technique has now shown it to be C. pyriformis, and closely related to the population on Mount Melbourne.