Mainland Species Research Articles

Climate change and the increase of human population will threaten conservation of Asian cobras

Asian cobras (genus Naja) are venomous snakes distributed from the Middle East to Southeast Asia. Because cobras often live near humans settlements, they are responsible for a large part of snakebite incidents and as such pose a challenge for public health systems. In the light of growing human populations, correctly mapping the present and future ranges of Asian cobras is therefore important for both biological conservation and public health management. Here, we mapped the potential climatic niches of ten Asian cobra species for both the present and the future, with the aim to quantify changes in climate and human population densities relative to their current and future ranges. Our analyses reveal that cobras that are adapted to dry climates and inhabit islands have narrow climatic niches, while those of mainland species with larger geographic ranges are much wider. We also found a higher degree of fragmentation of future cobra distributions; within the next 50 years, Asian cobras will lose an average of around 60% of their current suitable climatic range. In the near future, Naja mandalayensis, N. sputatrix, N. samarensis, and N. philippinensis are likely to have no accessible suitable climate space left. Besides, a further increase of human populations in this region may also exponentially accelerate the effects of anthropogenic impacts. Solutions for conservation may involve awareness and appropriate use of law to overcome the rate of habitat degradation and the increase of animal trade of Asian cobras, while promoting investment on health systems to avoid snakebite fatalities.

Seasonal Variation in Thermal Ecology and Microhabitat Use of Anolis carlliebi (Squamata: Dactyloidae) from a Xeric Scrubland in Central Mexico

Thermal ecology and microhabitat use by lizards are affected directly and indirectly by intrinsic (e.g., sex and body size) and extrinsic (e.g., environmental seasonality, vegetation cover, and wind speed) factors. Herein we evaluate the effect of seasonality and sex on field thermal ecology and microhabitat utilization of a population of Anolis carlliebi inhabiting a xeric scrubland in Central Mexico. Lizards were found primarily in full and filtered sun conditions, strongly associated, respectively, with inflorescences and leaves of Agave stricta. Males were slightly larger than females. Mean field body temperature did not differ between sexes within seasons, but males used higher perches than females in the warm season. We observed a seasonal shift in body temperature and perch use in males, which exhibited higher body temperatures and occupied wider and higher perches in the warm season. Female body temperature and perch use did not differ between seasons. This study reports the first case of a population of Anolis specializing in a species of Agave as microhabitat. These results add to our understanding of thermoregulation and microhabitat use of mainland species of Anolis since they face different environmental pressures than Caribbean species.

Divergence and introgression in small apes, the genus Hylobates, revealed by reduced representation sequencing.

Gibbons of the genus Hylobates, which inhabit Southeast Asia, show great diversity and comprise seven to nine species. Natural hybridisation has been observed in several species contact zones, but the history and extent of hybridisation and introgression in possibly historical and the current contact zones remain unclear. To uncover Hylobates species phylogeny and the extent of introgression in their evolution, genotyping by random amplicon sequencing-direct (GRAS-Di) was applied to 47 gibbons, representing seven Hylobates species/subspecies and two outgroup gibbon species. Over 200,000 autosomal single-nucleotide variant sites were identified. The autosomal phylogeny supported that divergence from the mainland species began ~3.5 million years ago, and subsequently occurred among the Sundaic island species. Significant introgression signals were detected between H. lar and H. pileatus, H. lar and H. agilis and H. albibarbis and H. muelleri, which all are parapatric and form ongoing hybrid zones. Furthermore, the introgression signals were detected in every analysed individual of these species, indicating a relatively long history of hybridisation, which might have affected the entire gene pool. By contrast, signals of introgression were either not detected or doubtful in other species pairs living on different islands, indicating the rarity of hybridisation and introgression, even though the Sundaic islands were connected during the Pliocene and Pleistocene glacial events.

THE ANOLES OF LA SELVA: NICHE PARTITIONING AND ECOLOGICAL MORPHOLOGY IN A MAINLAND COMMUNITY OF ANOLIS LIZARDS

Describing the relationships among morphology, behavior, and ecology is central to understanding the processes of evolutionary diversification. Anolis lizards are an excellent group for studying such ecomorphological relationships. Extensive research on anole ecological morphology has been conducted in the Caribbean, where sympatric species have repeatedly and convergently evolved to partition habitat through differential perch use. Six ecomorphs have been described, each with particular behavioral, morphological, and ecological characteristics well-suited for the microhabitat it occupies. However, little research has been conducted in mainland Central or South America, and a few case studies suggest that mainland anoles may not conform to the ecomorph classes recognized for Greater Antillean anoles. In this study, we examine the ecological morphology of sympatric mainland species of Anolis in a tropical lowland rainforest in Costa Rica and compare these species to the Caribbean ecomorphs. Our results show overlapping niches and substantial variability in habitat use across many species. Moreover, the relationship between relative hindlimb morphology and habitat use in Anolis humilis and Anolis limifrons does not conform to that of Caribbean species. Predation and fluctuating environmental conditions likely structure morphological variation differently in the mainland, leading the independent radiation of mainland anoles to produce divergent ecomorphological relationships compared with the Caribbean islands.

In situ radiation explains the frequency of dioecious palms on islands.

Dioecy has evolved up to 5000 times in angiosperms, despite the potentially high intrinsic costs to unisexuality. Dioecy prevents inbreeding, which is especially relevant on isolated islands when gene pools are small. Dioecy is also associated with certain dispersal traits, such as fruit size and type. However, the influence of dioecy on other life history traits and island distribution remains poorly understood. Here, we test the effect of dioecy on palm (Arecaceae) speciation rates, fruit size and frequency on islands. We used phylogenetic comparative methods to estimate the ancestral state of the sexual system and its impact on speciation rates and fruit size. Frequency of sexual systems, effect of insularity on the probability of being dioecious, and phylogenetic clustering of island dioecious vs. mainland species were inferred. Lastly, we determined the interplay of insularity and sexual system on speciation rates. Palms repeatedly evolved different sexual systems (dioecy, monoecy and polygamy) from a hermaphrodite origin. Differences in speciation rates and fruit size among the different sexual systems were not identified. An effect of islands on the probability of the palms being dioecious was also not found. However, we found a high frequency and phylogenetic clustering of dioecious palms on islands, which were not correlated with higher speciation rates. The high frequency and phylogenetic clustering may be the result of in situ radiation and suggest an 'island effect' for dioecious palms, which was not explained by differential speciation rates. This island effect also cannot be attributed to long-distance dispersal due to the lack of fruit size difference among sexual systems, and particularly because palm dispersal to islands is highly constrained by the interaction between the sizes of fruit and frugivores. Taken together, we suggest that trait flexibility in sexual system evolution and the in situ radiation of dioecious lineages are the underlying causes of the outstanding distribution of palms on islands.

The insular herpetofauna of Mexico: Composition, conservation, and biogeographic patterns.

We compile a Mexican insular herpetofaunal checklist to estimate endemism, conservation status, island threats, net taxonomic turnover among six biogeographic provinces belonging to the Nearctic and Neotropical regions, and the relationships between island area and mainland distance versus species richness. We compile a checklist of insular herpetofaunal through performing a literature and collection review. We define the conservation status according to conservation Mexican law, the Red List of International Union for Conservation of Nature, and Environmental Vulnerability Scores. We determine threat percentages on islands according to the 11 major classes of threats to biodiversity. We estimate the net taxonomic turnover with beta diversity analysis between the Nearctic and Neotropical provinces. The Mexican insular herpetofauna is composed of 18 amphibian species, 204 species with 101 subspecies of reptiles, and 263 taxa in total. Endemism levels are 11.76% in amphibians, 53.57% in reptiles, and 27.91% being insular endemic taxa. Two conservation status systems classify the species at high extinction risk, while the remaining system suggests less concern. However, all systems indicate species lacking assessment. Human activities and exotic alien species are present on 60% of 131 islands. The taxonomic turnover value is high (0.89), with a clear herpetofaunal differentiation between the two biogeographic regions. The species–area and species–mainland distance relationships are positive. Insular herpetofauna faces a high percentage of threats, with the Neotropical provinces more heavily impacted. It is urgent to explore the remaining islands (3,079 islands) and better incorporate insular populations and species in ecological, evolutionary, and systematic studies. In the face of the biodiversity crisis, islands will play a leading role as a model to apply restoration and conservation strategies.

A chromosome-level genome assembly for the tertiary relict plant Tetracentron sinense oliv. (trochodendraceae).

Tetracentron sinense and Trochodendron aralioides are two Tertiary relict species of large trees in the family Trochodendraceae with narrow distributions on the mainland and islands of eastern Asia. They belong to the order Trochodendrales, which is one of the four early-diverged eudicot lineages. These two relict species provide a good system in which to examine genomic changes that occurred as they survived during repeated climatic oscillations in the Quaternary. We sequenced the genome of Te. sinense and compared it with that of Tr. aralioides. We found that Te. sinense has a smaller genome size (986.3Mb) than that of Tr. aralioides (1610Mb). Repetitive elements made the major contribution to the contrasting genome sizes in the two species, with most bursts of repeats occurring within the past four million years when the climate oscillated greatly. These species share two rounds of whole-genome duplications. The mainland species Te. sinense had a larger effective population size than the island species Tr. aralioides after the largest glaciation during the Quaternary climatic oscillation. However, soon after this recovery stage, the effective population sizes of both species continued to decrease, although the current effective population size of Te. sinense is still larger than that of Tr. aralioides. We recovered three distinctly diverged clades through resequencing the genomes of 50 individuals across the distributional range of Te. sinense in China. Our results provide an important genomic resource with which to examine early trait evolution in the core eudicots and assist efforts to conserve this relict tree species.

Australian Bat Lyssavirus: Analysis of National Bat Surveillance Data from 2010 to 2016.

Australian bat lyssavirus (ABLV) was first described in 1996 and has been regularly detected in Australian bats since that time. While the virus does not cause population level impacts in bats and has minimal impacts on domestic animals, it does pose a public health risk. For this reason, bats are monitored for ABLV and a national dataset is collated and maintained by Wildlife Health Australia. The 2010–2016 dataset was analysed using logistic regression and time-series analysis to identify predictors of infection status in bats and the factors associated with human exposure to bats. In common with previous passive surveillance studies, we found that little red flying-foxes (Pteropus scapulatus) are more likely than other species to be infected with ABLV. In the four Australian mainland species of flying-fox, there are seasonal differences in infection risk that may be associated with reproductive cycles, with summer and autumn the seasons of greatest risk. The risk of human contact was also seasonal, with lower risk in winter. In line with other studies, we found that the circumstances in which the bat is encountered, such as exhibiting abnormal behaviour or being grounded, are risk factors for ABLV infection and human contact and should continue be key components of public health messaging. We also found evidence of biased recording of some types of information, which made interpretation of some findings more challenging. Strengthening of “One Health” linkages between public health and animal health services at the operational level could help overcome these biases in future, and greater harmonisation nationally would increase the value of the dataset.

First Record of the Long-Eared Bat (Plecotus; Chiroptera: Vespertilionidae) on Urup Island Highlights the Obscure Taxonomic Problem

Fauna of the Kuril Islands is understood insufficiently; in particular, the distribution and taxonomic relationships of bats in this territory are definitely understudied. Long-eared bats (Plecotus spp.) were first captured on the island of Urup during an expedition organized by the Russian Geographical Society in 2019. This capture became the first record of an indigenous land mammal on this island. Based on the peculiarities of geography, we assumed that the Japanese species P. sacrimontis would live on the Urup and Iturup Islands, as well as on the neighbouring Kunashir. However, a morphometric analysis of skull measurements and an analysis of the mitochondrial cytb gene show that long-eared bats from these two islands belong to the mainland species P. ognevi. This unexpected result raises questions regarding the postglacial history of the invasion of the long-eared bats to the islands, which probably occurred in two stages, and the taxonomic relationship between P. sacrimontis and P. ognevi.

What makes an island a suitable refuge for an endemic lizard?

AbstractAimTo identify and evaluate the environmental properties of the Mediterranean islands that make them a suitable habitat for their endemic lizards. This would represent an important improvement in our knowledge and would assist the conservation of these lizards, which are threatened by both the expansion of mainland species and the increasing intensity of human disturbance on these islands.LocationMediterranean Basin.MethodsI assessed the environmental associations of 50 species of lizard (19 endemic) across 552 Mediterranean islands using outlying mean index analysis. The strength of the species responses was assessed using binomial generalized linear models.ResultsThe presence of endemic species is positively correlated with the distance of the island from the mainland. Island connectivity is also positively correlated with an increased presence of endemic lizards, but not with an increased presence of mainland species (i.e. those with exclusive or mainly continental natural distribution). In addition, island size, temperature and vegetation productivity are positively correlated with the presence of mainland species. Outlying mean index (OMI) analysis showed that the endemic species occupy niche positions that are similar to the average environmental conditions in the archipelago, but frequently without using the entire range of niches. The mainland species usually occur in more peripheral positions in the environmental space, except for some highly expansive species.ConclusionsLizards that are endemic to the Mediterranean islands were found to be present on a large number of islands within an archipelago, but they quickly disappear as the conditions change, largely because of human activity. Large islands act as population reservoirs for mainland species, facilitating secondary colonization of peripheral islets.

A meta‐analysis of insularity effects on herbivory and plant defences

AbstractAimPlants on islands are often subjected to lower levels of herbivory relative to those found at mainland sites. As a consequence, island plants are predicted to exhibit lower levels of physical or chemical defences, which renders them more susceptible to introduced herbivores. Yet, instances of high pressure by superabundant herbivores native to islands have been reported in many insular systems, which presumably would result in heightened plant defences. To date, no quantitative review has been conducted to determine how common these contrasting patterns are and their implications for the evolution of plant‐herbivore interactions.LocationIslands worldwide.TaxonPlants, insects, molluscs, mammals.MethodsWe conducted a meta‐analysis of insularity effects on herbivory and plant defences by including studies that involved island‐mainland comparisons of the same plant species in both environments (90% of cases), or insular endemics versus mainland congeners (10% of cases). We tested for differences between mammalian and invertebrate (mollusc or insect) herbivory as well as between plant chemical and physical defences by specifying comparisons based on the type of herbivore (vertebrate or invertebrate) or plant trait included in the study.ResultsMammalian herbivory was significantly higher on islands than on mainlands. In contrast, no significant effect was observed on invertebrate herbivory. In addition, we found no significant difference in either plant physical or chemical defences between insular and mainland plants, though physical defences tended to be higher for plants on islands.Main conclusionsAll analysed mammal studies focused on species introduced to islands, suggesting greater susceptibility of insular plants to exotic mammals, whereas the lack of effects in the case of invertebrate herbivory suggests no difference in susceptibility to molluscs or insects between insular and mainland plants. Interestingly, plant trait patterns suggest a trend for increased physical defences by insular plants, possibly due to heightened pressure by exotic mammalian herbivores on islands, whereas chemical defences appear uncorrelated to differences in herbivory. These findings call for further experimental and observational studies measuring defences and herbivory for multiple sympatric plant species occurring at both mainland and island sites within a system, or comparing insular endemics to congeneric mainland species.

Large-scale phylogenomics reveals ancient introgression in Asian Hepatica and new insights into the origin of the insular endemic Hepatica maxima

Hepatica maxima is native to Ulleungdo, which is one of the oceanic islands in Korea, and it likely originated via anagenetic speciation from the Korean mainland species H. asiatica. However, the relationships among the Asian lineages remain unresolved. Phylogenomics based on plant genomes can provide new insights into the evolutionary history of plants. We first generated plastid, mitochondrial and transcriptome sequences of the insular endemic species H. maxima. Using the genomic data for H. maxima, we obtained a phylogenomic dataset consisting of 76 plastid, 37 mitochondrial and 413 nuclear genes from Asian Hepatica and two outgroups. Coalescent- and concatenation-based methods revealed cytonuclear and organellar discordance in the lineage. The presence of gynodioecy with cytoplasmic male sterility in Asian Hepatica suggests that the discordance is correlated with potential disruption of linkage disequilibrium between the organellar genomes. Species network analyses revealed a deep history of hybridization and introgression in Asian Hepatica. We discovered that ancient and recent introgression events occurred throughout the evolutionary history of the insular endemic species H. maxima. The introgression may serve as an important source of genetic variation to facilitate adaptation to the Ulleungdo environment.

Island-mainland lepidopteran assemblies: a blue-print for species conservation in fragmented habitats

The theory of island biogeography predicts that species diversity is lower on small islands and on islands far distant from the mainland, and higher on large islands with high habitat heterogeneity, and on islands close to the mainland. In addition, population and species persistence (i.e. their long-term survival) depends on life-history traits, including morphological, ecological and behavioural characteristics. These theories can also be used as basic hypotheses to test species persistence and community assembly of fragmented habitats. Lepidopteran communities living on small and isolated habitats, like small islands located along the northern German coast-line, provide an excellent model system to test for potential effects of species traits on their persistence and on the community assembly on islands and the mainland. Lepidopterans were assessed on the island Hallig Grode and on the adjoining mainland over a period of almost 50 years. About 500 species were recorded and classified according to their morphological, ecological and behavioural characteristics. Our data suggest less changes in the lepidopteran community composition on the island compared with the mainland. Yet, the number of species was considerably lower on the island compared with the mainland. The lepidopteran species community on the island was dominated by generalist species associated with meadows and grasslands. In contrast, lepidopteran species found at the mainland were frequently associated with forest and shrubs, and frequently showed a higher level of ecological specialization. Lepidopteran species caught on the island were equipped with more elongated wings compared with species found at the mainland. Our data suggest that the island situation functions as ecological filter allowing only specific species to persist and thus creates a subset of the mainland species community. Extrapolating our findings to isolated habitat patches across fragmented landscapes, we expect a similar filtering effect for species composition, and the long-term extinction of sedentary specialist species.

Island bees: do wood nesting bees have better island dispersal abilities?

For bees to reach isolated islands, they need to be able to cross large water barriers. However, functional traits such as nesting behavior, flight range, and body size can limit their dispersal. In this study, the bee faunas of seven different islands or island groups (Anholt, Canary Islands, Fiji Islands, Hawaiian Islands, Madeira, Malta, and Sri Lanka) were analyzed by comparing them to the mainland bee fauna. Nesting strategy and body size for each species were recorded. The relative distribution of traits among the island species were then compared to traits of the mainland species. We found that among islands located furthest from mainland, the proportion of wood nesting bees are higher than for those located closer to mainland, suggesting that wood nesting bees are more capable of island dispersal, most likely due to the associated rafting ability or the ease of being passively transported over water. The body size among the immigrated island species were shown to be commonly of moderate size, while a majority of mainland species were of small size, indicating that moderate sized bees—with longer flight range—were the more likely island migrators. The methods used could be useful for future studies of ecological influences on body size, as well as how other biological traits are adapted for migrant conditions, potentially serving as predictors in regards to climate change, dispersal ability, and control of invasive species.

Limbodessus skalei sp. nov., a new diving beetle species from the west Papuan Archipelago (Coleoptera: Dytiscidae, Bidessini).

Here we describe Limbodessus skalei sp. nov. from the island of Waigeo, off the coast of West Papua. It can be easily distinguished from the nearby New Guinea mainland species as well as the other members of the genus by its small size and testaceous elytra with conspicuous darker broad basal and subapical patches. Altogether four Limbodessus species are now known from the New Guinea region.

NUOVI ELEMENTI FAUNISTICI E STRATIGRAFICI DEL PLEISTOCENE SUPERIORE DEI NEBRODI (SICILIA NORD-ORIENTALE)

A new deposit of gravels containing Pleistocene mammal remains mostly belonging to Hippopotamus sp., but also with remains of some other mammals (Elephas sp., Ursus sp.) has been located at Rocca Scodonì near Torrenova, in the province of Messina (Sicily). The new deposit may be compared with that of the S. Teodoro cave near Acquedolci, which was already known in the literature. The location, the elevation above present sea level, the facies and faunal association are closely similar. Like the deposit of the S. Teodoro cave, the deposit of Rocca Scodonì belongs to a coastal plain now elevated at the altitude of 60—130 m a.s.l., overlying an abrasion terrace which can be referred to the Eutyrrhenian cycle. The facies of deposits show that the morphological terrace which is now elevated at the altitude of 60—130 m a.s.l. and extends along Ionian and Tyrrhenian sides of North—Eastern Sicily, was built up with deposits of different ages and environments, which are connected to the interaction between Pleistocene uplift of the region and three marine transgressions. The size of skeletal elements of Hippopotamus sp. appears to be very near to that of the mainland species H. amphibius. The new deposit shows that other mammal remains can probablv be found in the future along the northern slopes of carbonate massifs present in the area of Rocca Scodonì—S. Teodoro cave.

Genetic diversity, demographic history and neo-sex chromosomes in the Critically Endangered Raso lark.

Small effective population sizes could expose island species to inbreeding and loss of genetic variation. Here, we investigate factors shaping genetic diversity in the Raso lark, which has been restricted to a single islet for approximately 500 years, with a population size of a few hundred. We assembled a reference genome for the related Eurasian skylark and then assessed diversity and demographic history using RAD-seq data (75 samples from Raso larks and two related mainland species). We first identify broad tracts of suppressed recombination in females, indicating enlarged neo-sex chromosomes. We then show that genetic diversity across autosomes in the Raso lark is lower than in its mainland relatives, but inconsistent with long-term persistence at its current population size. Finally, we find that genetic signatures of the recent population contraction are overshadowed by an ancient expansion and persistence of a very large population until the human settlement of Cape Verde. Our findings show how genome-wide approaches to study endangered species can help avoid confounding effects of genome architecture on diversity estimates, and how present-day diversity can be shaped by ancient demographic events.

A new species of the genus Gonatodes (Squamata: Sauria: Sphaerodactylidae) from the western flank of the Cordillera Oriental in Colombia, with description of its hemipenial morphology

We describe a new sphaerodactylid lizard of the genus Gonatodes from the western flank of the Cordillera Oriental, Santander Department, Colombia based on morphological and molecular data. The new species is distinguished from all congeners by having a medium body size, by the absence of both a supraciliary spine and of clusters of distinctly enlarged conical scales on the sides and by having a subcaudal scale pattern (1'1") and a cryptic dorsal color pattern in both sexes. Additionally, we describe for the first time the hemipenial morphology for a species of the genus. The new species increases the number of Gonatodes known from Colombia to eight and is the only known species of the country, as well as the second known mainland species of the genus not exhibiting sexual dichromatism.

The geographical diversification in varanid lizards: the role of mainland versus island in driving species evolution.

Monitor lizards (Varanidae) inhabit both the mainland and islands of all geological types and have diversified into an exceptionally wide range of body sizes, thus providing an ideal model for examining the role of mainland versus island in driving species evolution. Here we use phylogenetic comparative methods to examine whether a link exists between body size-driven diversification and body size-frequency distributions in varanid lizards and to test the hypothesis that island lizards differ from mainland species in evolutionary processes, body size, and life-history traits (offspring number and size). We predict that: 1) since body size drives rapid diversification in groups, a link exists between body size-driven diversification and body size-frequency distributions; 2) because of various environments on island, island species will have higher speciation, extinction, and dispersal rates, compared with mainland species; 3) as a response to stronger intraspecific competition, island species will maximize individual ability associated with body size to outcompete closely-related species, and island species will produce smaller clutches of larger eggs to increase offspring quality. Our results confirm that the joint effect of differential macroevolutionary rates shapes the species richness pattern of varanid lizards. There is a link between body size-driven diversification and body size-frequency distributions, and the speciation rate is maximized at medium body sizes. Island species will have higher speciation, equal extinction, and higher dispersal rates compared with mainland species. Smaller clutch size and larger hatchling in the island than in mainland species indicate that offspring quality is more valuable than offspring quantity for island varanids.

Monograph of the Staphylinidae of Crete (Greece). Part I. Diversity and endemism (Insecta: Coleoptera)

With a geological history of long isolation, fragmentation, partial submersion, and subsequent rising, characterized by a remarkable diversity in topology, geology, and habitats, and the fifth-largest island of the Mediterranean, Crete has provided an ideal setting for speciation and developing a unique and diverse Staphylinidae fauna. Although beginning already in the middle of the 19th century, the exploration of this fauna gained momentum only recently. Based on a critical revision of literature data, on material collected during several recent field trips, and on additional previously unpublished records, a checklist of the Staphylinidae of Crete is compiled, including as many as 397 named species, with 115 of them reported from the island for the first time and with 48 new species described in the second part of the monograph. Additional unidentified and unnamed species, as well as species doubtfully or erroneously recorded from Crete are listed separately. The systematic, zoogeographic, and ecological composition of the Staphylinidae fauna is characterized with a special focus on the endemics. The latter are represented by 111 named and at least ten unnamed species, account for nearly one-third of the fauna, and mainly belong to the subfamilies Aleocharinae, Scydmaeninae, Pselaphinae, Paederinae, Leptotyphlinae, Staphylininae, and Omaliinae. More than half of them are even locally endemic. The genera with the greatest number of endemic species are Cephennium Müller & Kunze, 1822 of the Scydmaeninae (twelve named species) and Geostiba Thomson, 1858 of the Aleocharinae (nine named species). More than two-thirds of the endemic species are epigeic inhabitants of forests, bush and shrub habitats, grassland, and wetlands, approximately one-fourth is confined to deeper soil strata or endogean, and 8 % are myrmephilous. Slightly more than half (59 species; 53 %) of the endemics are most likely the result of in-situ radiation (18 lineages), the remainder of vicariance with mainland species. A comparison with other Mediterranean islands revealed that (a) total diversity of the Cretan fauna is significantly greater than that of other East Mediterranean islands except Corfu, but much lower than that of Corsica, Sardinia, and Sicily, (b) regarding the number of endemic species Crete ranks third behind Corsica and Sardinia, and (c) the rate of endemism is greater in Crete than in any other Mediterranean island. Explanations for the observed differences in the diversity and composition of the faunas of the islands are discussed. Stichoglossa graeca Bernhauer, 1905, a species of which previously only the lectotype was known, is redescribed and illustrated. Six synonymies are proposed and one name is revalidated: Phloeocharis longipennis Fauvel, 1875 = P. hummleri Bernhauer, 1915, syn. nov.; Phytosus balticus Kraatz, 1859 = P. holtzi Bernhauer, 1935, syn. nov.; Atheta nigra (Kraatz, 1856) = A. biroi Scheerpeltz, 1964, syn. nov.; Domene stilicina (Erichson, 1840) = D. lohseiana Bordoni, 1977, syn. nov.; Oedichirus rubronotatus Pic, 1903, revalidated = O. reitteri Bernhauer, 1908, syn. nov.; Pseudolathra quadricollis (Fauvel, 1875) = P. cretensis Bordoni, 1986, syn. nov. A lectotype is designated for Stichoglossa graeca Bernhauer, 1905. Two species are reported from Greece for the first time.