Morphometric differentiation between the Italian hare (Lepus corsicanus De Winton, 1898) and the European brown hare (Lepus europaeus Pallas, 1778)

Pathological and virological insights from an outbreak of European brown hare syndrome in the Italian hare (Lepus corsicanus)

European brown hare syndrome (EBHS) is a highly contagious and fatal viral disease, mainly affecting European brown hares (Lepus europaeus). The etiological agent, EBHS virus (EBHSV), belongs to the Lagovirus genus within the Caliciviridae family. The Italian hare (Lepus corsicanus) is endemic to Central-Southern Italy and Sicily and is classified as a vulnerable species. L. corsicanus is known to be susceptible to EBHS, but virological data available is scarce due to the few cases detected so far. In this study, we describe the occurrence of EBHS in two free-ranging L. corsicanus, found dead in a protected area of Central Italy. The two hares were identified as L. corsicanus using phenotypic criteria and confirmed through mitochondrial DNA analysis. Distinctive EBHS gross lesions were observed at necropsy and confirmed by subsequent histological examination. EBHSV was detected in the livers of the two animals initially using an antigen detection ELISA, followed by an EBHSV-specific reverse transcription-PCR, thus confirming the viral infection as the probable cause of death. The EBHS viruses detected in the two hares were identical, as based on blast analysis performed for the VP60 sequences and showed 98.86% nucleotide identity and 100% amino acid identity with strain EBHSV/GER-BY/EI97.L03477/2019, isolated in Germany in 2019. Phylogenetic analysis places our virus in group B, which includes strains that emerged after the mid-1980s. This study supports previous reports of EBHS in L. corsicanus and further expands the knowledge of the pathological and virological characteristics of the etiological agent. The ability of EBHSV to cause a fatal disease in the Italian hare represents a serious threat to the conservation of this vulnerable species, especially in populations kept in enclosed protected areas.

Parasitological Survey in European Brown Hare (Lepus europaeus Pallas, 1778) Breeding Facilities in Southern Italy

Parasites are considered important regulating factors of hosts' population dynamics, not only in free-ranging wildlife, but also in captive bred animals. To date, only few studies have been carried out to assess the parasitic communities of the European brown hare in Southern Italy, and only one focused on animals in captivity. The aim of the present survey was to assess the composition of the endoparasite community in game hares bred for restocking purposes. For this purpose, 215 fecal pools collected in eight different breeding facilities were examined by qualitative and quantitative coprological techniques. Parasites characterized by a direct life cycle, including six species of coccidia from the genus Eimeria and the nematode Trichostrongylus retorataeformis, proved to be the most prevalent parasites. Further helminthic infestations by Passalurus ambiguous, Strongylosides papillosus, Cittotenia spp. and Dicrocoelium dendriticum were also detected, but with an overall prevalence lower than 20%. The present study contributes to increasing knowledge on the health status of a poorly investigated species, and is useful for optimizing breeding efforts in captivity.

Helminth biocoenosis of Lepus europaeus meridiei (Hilzheimer, 1906) from Pianosa island, Italy

Pianosa is a 10 km² Italian island in the Tyrrhenian Sea which is part of the Tuscan Archipelago National Park. In this island lives a brown hare population which, according to the literature, belongs to the ancestral taxon Lepus europaeus meridei that offers a unique opportunity to observe how the parasite biocoenosis shapes in condition of isolation, limited space availability and high population density. The aim of this work is to describe the helminth component community of a non-managed, isolated, and dense hare population, evaluating host-parasite relationship and parasite community structure. All 26 analyzed hares (13 males and 13 females) were in good physical conditions, and all of them harboured exclusively the nematode Protostrongylus oryctolagi only. This is the first report of this lungworm species in Italy. The estimated overall abundance was 48.15 worms per examined hare (range 3-258, median 50) and the parasites were unevenly distributed across host population, with few hosts having most parasites (aggregated or overdispersed distribution). No significant relationship was detected between the number of isolated parasites and hare sex and weigh. The effect of the isolation of Pianosa's hare population seems to have acted reducing parasite richness, while the high host density is probably the cause of the high prevalence and abundance of the single helminth species collected. In conclusion, despite the low impact of parasites confirmed also by the overdispersed parasite distribution, the low diversity of the studied parasite community sounds a warning for the management of the hare population and the whole Pianosa's ecosystem.

Spatiotemporal Overlap between the European Brown Hare and Its Potential Predators and Competitors

Analysis of spatiotemporal partitioning is pivotal to shed light on interspecific coexistence. Most research effort has involved large-sized carnivores and their prey, whereas little attention has been devoted to lagomorphs. We assessed spatiotemporal overlap among the European brown hare Lepus europaeus and its potential competitors and predators through camera-trapping in an area in Central Italy. We estimated the interspecific patterns of the spatiotemporal activity rhythms of brown hares, its potential predators (the red fox Vulpes vulpes, the pine marten Martes martes, the domestic cat Felis catus, and the domestic dog Canis familiaris), and a competitor, the roe deer Capreolus capreolus. Brown hare activity was studied in natural conditions as well as in a fenced area that excluded terrestrial predators and competitors. Free-ranging hares developed a more nocturnal behavior to avoid diurnal predators (i.e., domestic carnivores and martens). Although high temporal overlap was observed between free-ranging brown hares and both red foxes (82%) and roe deer (81%), hares avoided fox by being more active on darkest nights, as well as avoided roe deer through spatial partitioning. We suggest that hares may adapt their spatiotemporal behavior to avoid potential predators and competitors.

Contribution to the ecology of the Italian hare (Lepus corsicanus)

The Italian hare (Lepus corsicanus) is endemic to Central-Southern Italy and Sicily, classified as vulnerable due to habitat alterations, low density and fragmented populations and ecological competition with the sympatric European hare (Lepus europaeus). Despite this status, only few and local studies have explored its ecological features. We provided some key traits of the ecological niche of the Italian hare as well as its potential distribution in the Italian peninsula. All data derived from genetically validated presences. We generated a habitat suitability model using maximum entropy distribution model for the Italian hare and its main competitor, the European hare. The dietary habits were obtained for the Italian hare with DNA metabarcoding and High-Throughput Sequencing on faecal pellets. The most relevant environmental variables affecting the potential distribution of the Italian hare are shared with the European hare, suggesting a potential competition. The variation in the observed altitudinal distribution is statistically significant between the two species.The diet of the Italian hare all year around includes 344 plant taxa accounted by 62 families. The Fagaceae, Fabaceae, Poaceae, Rosaceae and Solanaceae (counts > 20,000) represented the 90.22% of the total diet. Fabaceae (60.70%) and Fagaceae (67.47%) were the most abundant plant items occurring in the Spring/Summer and Autumn/Winter diets, respectively. The Spring/Summer diet showed richness (N = 266) and diversity index values (Shannon: 2.329, Evenness: 0.03858, Equitability: 0.4169) higher than the Autumn/Winter diet (N = 199, Shannon: 1.818, Evenness: 0.03096, Equitability: 0.3435). Our contribution adds important information to broaden the knowledge on the environmental (spatial and trophic) requirements of the Italian hare, representing effective support for fitting management actions in conservation planning.

Structure and Sense Organs of Ovipositors of an Endoparasitoid Aprostocetus causalis and an Ectoparasitoid Quadrastichus mendeli in Leptocybe spp

Little is known of the olfactory mechanisms of host detection in the ovipositors of endoparasitoids and ectoparasitoids. An endoparasitoid Aprostocetus causalis La Salle & Wu (Hymenoptera: Eulophidae) and an ectoparasitoid Quadrastichus mendeli Kim & La Salle (Hymenoptera: Eulophidae: Tetrastichinae) are the two parasitoids of the eucalyptus gall wasp Leptocybe spp. Structures and sense organs of ovipositors of A. causalis and Q. mendeli were studied using scanning and transmission electron microscopy, which provided essential information for exploring the mechanism of host detection by endoparasitoid and ectoparasitoid. The ovipositors of two parasitoids consisted of the first and second valvulae and ended in a pointed tip. There were three types of microtrichia, two types of sensilla chaetica, and one type of sensilla campaniformia on the ovipositors of A. causalis and Q. mendeli. However, Q. mendeli has the fourth type of microtrichia on the ovipositor. The morphology, types, distribution, length, and width of these sensilla and microtrichia were described, and their possible functions are discussed in conjunction with the stinging, oviposition, and the host selection process.

Mitochondrial and nuclear DNA reveals reticulate evolution in hares (Lepus spp., Lagomorpha, Mammalia) from Ethiopia

For hares (Lepus spp., Leporidae, Lagomorpha, Mammalia) from Ethiopia no conclusive molecular phylogenetic data are available. To provide a first molecular phylogenetic model for the Abyssinian Hare (Lepus habessinicus), the Ethiopian Hare (L. fagani), and the Ethiopian Highland Hare (L. starcki) and their evolutionary relationships to hares from Africa, Eurasia, and North America, we phylogenetically analysed mitochondrial ATPase subunit 6 (ATP6; n = 153 / 416bp) and nuclear transferrin (TF; n = 155 / 434bp) sequences of phenotypically determined individuals. For the hares from Ethiopia, genotype composition at twelve microsatellite loci (n = 107) was used to explore both interspecific gene pool separation and levels of current hybridization, as has been observed in some other Lepus species. For phylogenetic analyses ATP6 and TF sequences of Lepus species from South and North Africa (L. capensis, L. saxatilis), the Anatolian peninsula and Europe (L. europaeus, L. timidus) were also produced and additional TF sequences of 18 Lepus species retrieved from GenBank were included as well. Median joining networks, neighbour joining, maximum likelihood analyses, as well as Bayesian inference resulted in similar models of evolution of the three species from Ethiopia for the ATP6 and TF sequences, respectively. The Ethiopian species are, however, not monophyletic, with signatures of contemporary uni- and bidirectional mitochondrial introgression and/ or shared ancestral polymorphism. Lepus habessinicus carries mtDNA distinct from South African L. capensis and North African L. capensis sensu lato; that finding is not in line with earlier suggestions of its conspecificity with L. capensis. Lepus starcki has mtDNA distinct from L. capensis and L. europaeus, which is not in line with earlier suggestions to include it either in L. capensis or L. europaeus. Lepus fagani shares mitochondrial haplotypes with the other two species from Ethiopia, despite its distinct phenotypic and microsatellite differences; moreover, it is not represented by a species-specific mitochondrial haplogroup, suggesting considerable mitochondrial capture by the other species from Ethiopia or species from other parts of Africa. Both mitochondrial and nuclear sequences indicate close phylogenetic relationships among all three Lepus species from Ethiopia, with L. fagani being surprisingly tightly connected to L. habessinicus. TF sequences suggest close evolutionary relationships between the three Ethiopian species and Cape hares from South and North Africa; they further suggest that hares from Ethiopia hold a position ancestral to many Eurasian and North American species.

Factors influencing the importation and establishment in Australia of the European hare (Lepus europaeus)

Hares were introduced into Australia early in the period of European settlement. This study examined historical issues of newspapers and other historical sources to ascertain the number of importations, the number of hares landed alive, their destinations, relevant habitat characteristics at the sites of the releases, and whether the propagules became established and spread. Forty shipments were identified, and one or more live hares were landed from 27 of those shipments, totalling ~86 live hares, and resulted in the establishment of 10 populations of hares. The climate and the grasses at the known release sites were suitable for Lepus europaeus and predators were rigorously suppressed, which, acting together with the wealth, power, influence, and determination of the proponents of the importations, made establishment of hares in Australia almost certain. However, 11 of the hares landed alive were almost certainly L. nigricollis, and the fates of seven of those hares are not known. There are populations of hares in Australia at sites suited to L. nigricollis but not L. europaeus on the basis of climate and availability of C4 grass types, and the taxonomic status of those hares should be examined.

Detection of the new emerging rabbit haemorrhagic disease type 2 virus (RHDV2) in Sicily from rabbit (Oryctolagus cuniculus) and Italian hare (Lepus corsicanus)

Rabbit haemorrhagic disease virus (RHDV), a member of the genus Lagovirus, causes rabbit haemorrhagic disease (RHD), a fatal hepatitis of rabbits, not previously reported in hares. Recently, a new RHDV-related virus emerged, called RHDV2. This lagovirus can cause RHD in rabbits and disease and mortality in Lepus capensis (Cape hare). Here we describe a case of RHDV2 infection in another hare species, Lepus corsicanus, during a concurrent RHD outbreak in a group of wild rabbits. The same RHDV2 strain infected rabbits and a hare, also causing a RHD-like syndrome in the latter. Our findings confirmed the capability of RHDV2 to infect hosts other than rabbits and improve the knowledge about the epidemiology and the host range of this new lagovirus.

Molecular phylogenetics and biogeography of Lepus in Eastern Asia based on mitochondrial DNA sequences

In spite of several classification attempts among taxa of the genus Lepus, phylogenetic relationships still remain poorly understood. Here, we present molecular genetic evidence that may resolve some of the current incongruities in the phylogeny of the leporids. The complete mitochondrial cytb, 12S genes, and parts of ND4 and control region fragments were sequenced to examine phylogenetic relationships among Chinese hare taxa and other leporids throughout the World using maximum parsimony, maximum likelihood, and Bayesian phylogenetic reconstruction approaches. Using reconstructed phylogenies, we observed that the Chinese hare is not a single monophyletic group as originally thought. Instead, the data infers that the genus Lepus is monophyletic with three unique species groups: North American, Eurasian, and African. Ancestral area analysis indicated that ancestral Lepus arose in North America and then dispersed into Eurasia via the Bering Land Bridge eventually extending to Africa. Brooks Parsimony analysis showed that dispersal events followed by subsequent speciation have occurred in other geographic areas as well and resulted in the rapid radiation and speciation of Lepus. A Bayesian relaxed molecular clock approach based on the continuous autocorrelation of evolutionary rates along branches estimated the divergence time between the three major groups within Lepus. The genus appears to have arisen approximately 10.76 MYA (+/-0.86 MYA), with most speciation events occurring during the Pliocene epoch (5.65+/-1.15 MYA approximately 1.12 +/- 0.47 MYA).

Hare populations in Europe: intra and interspecific analysis of mtDNA variation

We report results of a project aimed at analysing genetic diversification in Lepus corsicanus (italian hare), carried out at the INFS as part of an ongoing project on the biology of L. corsicanus. Samples of Italian hare were collected in different localities in central-southern Italy and Sicily. Moreover samples of L. europaeus (brown hare), as well as other species of the genus Lepus, were collected in Italy and Europe in order to define the phylogenetic relationships of the Italian hare. Results show a clear genetic distinction of the Italian hare. Consequently the status of true species is warranted at the molecular level. Phylogenetic relationships among species suggest the presence of two distinct groups, the Italian hare belonging to an evolutionary lineage including species which probably originated in a glacial refugia in southern Europe before colonization by the brown hare. On the other hand the brown hare belongs to a different lineage including species of African origins.

Ancient introgression of Lepus timidus mtDNA into L. granatensis and L. europaeus in the Iberian Peninsula

A 587 bp fragment of cytochrome b sequences from 90 individuals of 15 hare (Lepus) species and two outgroups were phylogenetically analysed and compared to an analysis derived from 474 bp sequences of the nuclear transferrin gene. Mountain hare (Lepus timidus) type mtDNA was observed in L. granatensis and L. europaeus from the Iberian Peninsula, far away from the extant distributional range of L. timidus. In addition to these two hare species, other hare species may also contain mtDNA from L. timidus. This species may have introgressed with other species of Lepus that occur within its present range, or where fossils indicate its historical presence during glacial periods. L. timidus mtDNA is common in the northern part of the L. granatensis range. Finally, we reassessed the phylogenetic relationships of the five European hare species based on both mitochondrial and nuclear DNA sequences.