From offshore to onshore: multiple origins of shallow-water corals from deep-sea ancestors

Shallow-water tropical reefs and the deep sea represent the two most diverse marine environments. Understanding the origin and diversification of this biodiversity is a major quest in ecology and evolution. The most prominent and well-supported explanation, articulated since the first explorations of the deep sea, holds that benthic marine fauna originated in shallow, onshore environments, and diversified into deeper waters. In contrast, evidence that groups of marine organisms originated in the deep sea is limited, and the possibility that deep-water taxa have contributed to the formation of shallow-water communities remains untested with phylogenetic methods. Here we show that stylasterid corals (Cnidaria: Hydrozoa: Stylasteridae)--the second most diverse group of hard corals--originated and diversified extensively in the deep sea, and subsequently invaded shallow waters. Our phylogenetic results show that deep-water stylasterid corals have invaded the shallow-water tropics three times, with one additional invasion of the shallow-water temperate zone. Our results also show that anti-predatory innovations arose in the deep sea, but were not involved in the shallow-water invasions. These findings are the first robust evidence that an important group of tropical shallow-water marine animals evolved from deep-water ancestors.     

中国窄吉丁属二新种及一新记录种记述(鞘翅目:吉丁科)

记述脊窄吉丁种团Agrilus japanocarinatus species-group 2新种:长脊窄吉丁Agrilus longicarinus sp.nov.(广东)和林氏窄吉丁 A.lini sp.nov.(海南).首次记录了阿氏窄吉丁 A.arsenevi Jendek,2009.编制了该种团的中国种检索表...     

Phylogeny of Rhododendron section Vireya (Ericaceae) based on two non-coding regions of cpDNA

Section Vireya (Blume) Copel.f. is one of the most morphologically diverse groups of the genus Rhododendron. Vireyas have a unique distribution for the genus, being predominantly found throughout the Malesian Archipelago. The alpha taxonomy of section Vireya is relatively well understood and taxa are easily distinguished from other rhododendrons by their general appearance. Defining characteristics of the section the possession of seeds with tailed appendages at both ends, the twisting of capsule valves after opening, placentas that separate as thread-like structures from the central axis as the capsule opens are all subject to exceptions. Phylogenetic analyses of two cpDNA regions, psbA-trnH and trnT-trnL intergenic spacers are reported. The results of each analysis were generally congruent, with clades relating strongly to geographic areas. Section Vireya is monophyletic with the inclusion of at least one species of section Rhododendron. Only two of the seven subsections currently circumscribed are monophyletic: Malayovireya Sleumer and Siphonovireya Sleumer. ``Euvireya', all subsections excluding the paraphyletic subsection Pseudovireya, is monophyletic and includes two major clades, one restricted to eastern Malesia and the other to the western and middle Malesia.     

Phylogeny of the tribe Empoascini (Hemiptera: Cicadellidae: Typhlocybinae) based on morphological characteristics,with reclassification of the Empoasca generic group

A morphology‐based phylogenetic analysis of the tribe Empoascini (Hemiptera: Cicadellidae: Typhlocybinae) is presented for 58 of 83 formerly recognized genera based on 99 morphological characters of adults. The results support excluding the New World Beamerana generic group from Empoascini. The remaining genera of Empoascini were recovered as a monophyletic sister group of Dikraneurini. Previously recognized tribes Jorumini and Helionini are derived from within Empoascini and are considered synonyms of the latter tribe. Three previously recognized informal generic groups, the Empoasca group, Alebroides group and Usharia group were paraphyletic but the Ficiana group was recovered as monophyletic based on five synapomorphies. Genera previously placed in the Alebroides group represent at least six independent lineages, indicating that the hind wing character separating this group from the Empoasca group (CuA and MP veins free) is highly homoplasious. Empoasca (sensu lato) is also paraphyletic. Thus, twelve previously recognized subgenera of Empoasca are elevated to genus status and five species groups of Empoasca from the New World are recognized as separate new genera. Sikkimasca Dworakowska, 1993 is treated as synonym of Marolda Dworakowska, 1977 based on the phylogeny. Biogeographic analysis suggests that Empoascini most likely first evolved in the Oriental region and spread to other biogeographic realms more recently by multiple independent invasions.     

EARLY PLIOCENE COLIIDAE (AVES,COLIIFORMES) FROM LANGEBAANWEG,SOUTH AFRICA

Rich, P. V. & Haarhoff, P. J. 1985. Early Pliocene Coliidae (Aves, Coliiformes) from Langebaanweg, South Africa. Ostrich 56: 20–41.

Members of the Coliiformes (mousebirds) are osteologically unique, clearly distinct from all other orders of birds. They have a strikingly enlarged and broadened pygostyle, and may represent an ancient group that arose from piciform-coraciiform stock in the early Tertiary. A review of the osteology of the Coliidae indicates that the subgenera Colius (Colius) and C. (Urocolius) warrant generic rank. The mousebird remains from the early Pliocene Varswater Formation at Langebaanweg, Cape Province, represent at least one new species, Colius hendeyi, that is closely related to C. colius and C. striatus.     

Radiation, multiple dispersal and parallelism in the skinks, Chalcides and Sphenops (Squamata: Scincidae), with comments on Scincus and Scincopus and the age of the Sahara Desert

Phylogenetic analysis using up to 1325 base pairs of mitochondrial DNA from 179 specimens and 30 species of Chalcides, Sphenops, Eumeces, Scincopus and Scincus indicates that Sphenops arose twice independently within Chalcides. It is consequently synonymized with that genus. Chalcides in this broader sense originated in Morocco, diversifying into four main clades about 10 Ma, after which some of its lineages dispersed widely to cover an area 40 times as large. Two separate lineages invaded the Canary Islands and at least five main lineages colonized southern Europe. At least five more spread across northern Africa, one extending into southwest Asia. Elongate bodies with reduced limbs have evolved at least four times in Chalcides, mesic 'grass-swimmers' being produced in one case and extensive adaptation to life in loose desert sand in two others. In clade, Chalcides striatus colonized SW Europe from NW Africa 2.6 Ma and C. chalcides mainland Italy 1.4 Ma, both invasions being across water, while C. c. vittatus reached Sardinia more recently, perhaps anthropogenically, and C. guentheri spread 1200km further east to Israel. C. minutus is a composite, with individuals from the type locality forming a long independent lineage and the remaining ones investigated being most closely related to C. mertensi. In the Northern clade, C. boulengeri and C. sepsoides spread east through sandy habitats north of the Sahara about 5 Ma, the latter reaching Egypt. C. bedriagai invaded Spain around the same time, perhaps during the Messinian period when the Mediterranean was dry, and shows considerable diversification. Although it is currently recognized as one species, the C. ocellatus clade exhibits as much phylogenetic depth as the other main clades of Chalcides, having at least six main lineages. These have independently invaded Malta and Sardinia from Tunisia and also southwest Arabia C. o. humilis appears to have spread over 4000 km through the Sahel, south of the Sahara quite recently, perhaps in the Pleistocene. In the Western clade of Chalcides, C. delislei appears to have dispersed in a similar way. There were also two invasions of the Canary Islands: one around 5 Ma by C. simonyi, and the other about 7 Ma by the ancestor of C. viridanus+C. sexlineatus. C. montanus was believed to be related to C. lanzai of the Northern clade, but in the mtDNA tree it is placed within C. polylepis of the Western clade, although this may possibly be an artifact of introgression. The Eumeces schneideri group, Scincopus and Scincus form a clade separate from Chalcides. Within this clade, the geographically disjunct E. schneideri group is paraphyletic. One of its members, E. algeriensis is the sister taxon to Scincopus, and Scincus may also be related to these taxa. The phylogeny suggests Scincopus entered desert conditions in Africa, up to 9.6 Ma and the same may have been true of Scincus up to 11.7 Ma. Scincus appears to have diversified and spread into Arabia around 6 Ma. Dates of origin and divergence of these skinks, desert Chalcides and other squamates agree with recent geological evidence that the Sahara is at least 5-7 My old. The subspecies Chalcides viridanus coeruleopunctatus is upgraded to the species level as C. coeruleopunctatus stat nov., on the basis of its large genetic divergence from C. v. viridanus.     

Phylogenomics of Unusual Histone H2A Variants in Bdelloid Rotifers

Rotifers of Class Bdelloidea are remarkable in having evolved for millions of years, apparently without males and meiosis. In addition, they are unusually resistant to desiccation and ionizing radiation and are able to repair hundreds of radiation-induced DNA double-strand breaks per genome with little effect on viability or reproduction. Because specific histone H2A variants are involved in DSB repair and certain meiotic processes in other eukaryotes, we investigated the histone H2A genes and proteins of two bdelloid species. Genomic libraries were built and probed to identify histone H2A genes in Adineta vaga and Philodina roseola, species representing two different bdelloid families. The expressed H2A proteins were visualized on SDS-PAGE gels and identified by tandem mass spectrometry. We find that neither the core histone H2A, present in nearly all other eukaryotes, nor the H2AX variant, a ubiquitous component of the eukaryotic DSB repair machinery, are present in bdelloid rotifers. Instead, they are replaced by unusual histone H2A variants of higher mass. In contrast, a species of rotifer belonging to the facultatively sexual, desiccation- and radiation-intolerant sister class of bdelloid rotifers, the monogononts, contains a canonical core histone H2A and appears to lack the bdelloid H2A variant genes. Applying phylogenetic tools, we demonstrate that the bdelloid-specific H2A variants arose as distinct lineages from canonical H2A separate from those leading to the H2AX and H2AZ variants. The replacement of core H2A and H2AX in bdelloid rotifers by previously uncharacterized H2A variants with extended carboxy-terminal tails is further evidence for evolutionary diversity within this class of histone H2A genes and may represent adaptation to unusual features specific to bdelloid rotifers.     

RAPID AND REPEATED INVASIONS OF FRESH WATER BY THE COPEPOD EURYTEMORA AFFINIS

Invasions of fresh water by marine organisms have been of great interest to evolutionary biologists and paleontologists because they typically constitute major evolutionary transitions. Recent (< 200 years) invasions of fresh water by brackish or marine species offer an opportunity to understand mechanisms underlying these events, but pathways of invasion from salt water have not been confirmed using genetic data. This study employed mitochondrial DNA sequences (652 base pairs from the cytochrome oxidase I (COI) gene) to reconstruct the geographic and evolutionary history of freshwater invasion by the common estuarine and saltmarsh crustacean Eurytemora affinis (Copepoda; Poppe 1880). Phylogenetic analysis of populations from North America, Europe, and Asia revealed at least eight independent invasions of fresh water from genetically distinct lineages. At least five of these freshwater invasions most likely arose independently in different river drainages, recently from saltwater sources within each river drainage. An analysis of molecular variance (AMOVA) was performed at three geographic scales (among continents, among drainages, and within drainages) to assess the hierarchical distribution of genetic variance. Results indicated that 52% of the genetic variance was explained by differences among drainages, 43% by differences among continents, but only 5% by differences within drainages, thus supporting geographic patterns of invasions inferred from the phylogeny. Physiological experiments were performed to determine whether adults and larvae from saltwater populations could tolerate freshwater conditions. Transfer to zero salinity resulted in high mortalities, but with some survival to the second generation in one population. This study provides genetic evidence and physiological support for rapid transitions from a saline life history into fresh water, with repeated invasions on a global scale.     

Pugs of the tribe Eupitheciini (Lepidoptera,Geometridae): the history of study and distribution over biogeographic regions

The World fauna of the tribe Eupitheciini is the most species-rich in the family Geometridae. This tribe includes about 1900 species (almost 3000 species-group names) from 47 genera; about one third of the genera (15) are monotypic. The generic diversity of Eupitheciini is the highest in the Australian (38 genera, 11 of them endemic) and Oriental regions (32 genera, 4 endemic) and the lowest in the Neotropical Region (possibly one genus only). The faunas of different biogeographic regions can be arranged in following order by their species richness: the Palaearctic (487 species), Oriental (397), Neotropical (346), Australian (251), Afrotropical (198), and Nearctic Regions (166 species). Eupithecia is the most species-rich genus in the family Geometridae and the entire order Lepidoptera, and one of the largest genera in the whole World fauna of insects. The greatest number of species of this genus is recorded in the Palaearctic Region (466 species), where Eupithecia accounts for about 95% of the tribe Eupitheciini. The mainland of the Oriental Region (especially the Himalayas) is also very species-rich; however the proportion of the Eupithecia representatives decreases towards Malaysia, Sundaland, and the Australian Region (about 2% of the tribe). The Eupitheciini faunas have the greatest similarity at the generic level between the Oriental and Australian Regions (the Jaccard and Sørensen coefficient values being 0.62 and 0.77, respectively). The Palaearctic fauna is more similar to the Afrotropical and Oriental faunas at the genus-group level. On the whole, the fauna of the Nearctic Region is similar to that the West Palaearctic, with the exception of the fact that representatives of the genera Gymnoscelis and Chloroclystis are absent in North America, although two endemic genera Nasusina and Prorella are present. At the genus-group level, the Nearctic fauna of Eupitheciini is more similar to the Neotropical (the Jaccard and Sørensen coefficients 0.20 and 0.33, respectively) than to the Palaearctic fauna (0.17 and 0.29). The number of synonymies is very high in the tribe Eupitheciini because of the homogeneity of this group, whose species are difficult to identify without the use of elaborate anatomical techniques. Modern revisions, catalogues, surveys, and atlases on Eupitheciini are absent for many countries and large geographic regions. Revisions of pugs of the tribe Eupitheciini for some biogeographic regions are extremely difficult because of fragmentation of entomological collections including the type specimens of many species-group taxa. A large fraction of synonyms is characteristic of parts of the World with the best known faunas: Europe (64% of synonyms) and North America (39%). On the contrary, the lowest levels of synonymy are typical of the less known faunas of the regions situated at the equatorial latitudes, namely the Neotropical (9%) and Afrotropical (8%) ones.     

Thirteen new species of Dendrochilum (Orchidaceae), a new record from Burma, and a checklist of the genus in East Malesia

Pedersen, H. Æ. 1995. Thirteen new species of Dendrochilum (Orchidaceae), a new record from Burma, and a checklist of the genus in East Malesia. — Nord. J. Bot. 15: 381402. Copenhagen. ISSN 0107–055X.
Seven new species of Dendrochilum are described from the Philippines, viz. D. amesianum, D. flexuosum, D. louisianum, D. parvipapillatum, D. plocoglottoides, D. quisumbingianum and D. tetradactyliferum . The widespread species D. longifolium is recorded from Burma for the first time, and an annotated checklist of Dendrochilum in East Malesia, i.e. the Lesser Sunda Islands, Sulawesi, the Moluccas, and New Guinea is given. This list enumerates a total of 21 species, including D. cornutum and D. pallideflavens which are here recorded from East Malesia for the first time. Six species in the checklist are described as new, viz. D. ambangense, D. citrinum, D. erectila-bium, D. eymae, D. galeatum , and D. longipedicellatum .     

Current status of the Drosophila melanogaster species-group (Diptera)

Abstract. The Drosphila melanogaster species-group, established by Sturtevant (1942) for fourteen species, is now known to contain 115 described species here divided into twelve named subgroups (including one newly proposed), as well as further undescribed species. Three of the species, melanogaster, simulans and ananassae , are cosmopolitan; two others, kikkawai and malerkotliana , are widespread in the southern hemisphere, the latter apparently a recent introduction to South America. The greatest numbers of species otherwise occur in the Oriental region with smaller numbers in the Ethiopian, eastern Palaearctic and Australian regions and in several islands of the South Pacific. D.rajasekari and D.raychaudhurii are synonymized with D.biamipes;also D.andamanensis Parshad & Singh is synonymized with D.andamanensis Gupta & Raychaudhuri.     

Phylogeography of Poorly Dispersing Net-Winged Beetles: A Role of Drifting India in the Origin of Afrotropical and Oriental Fauna

Ancient dispersal history may be obscured by subsequent dispersal events. Therefore, we intend to investigate the biogeography of metriorrhynchine net-winged beetles, a group characterized by limited dispersal propensity. We used DNA data to construct phylogenies and the BayesTraits and RASP programs to identify putative ancestral areas. Further, we inferred ultrametric trees to estimate the ages of selected nodes. The time frame is inferred from tectonic calibrations and the general mutation rate of the mitochondrial genes. Metriorrhynchini consists of two lineages with Afro/Oriental and Australian distributions. The basal lineages originated in Eastern Gondwana after the split of Australia, India and Madagascar; the Afrotropical and Madagascar Metriorrhynchini separated from the Oriental clades 65 and 62 mya. Several already diversified lineages colonized continental Asia 55–35 mya. A few genera of the Australian clade dispersed to the Oriental region 5–15 mya and reached Eastern India and Southern China. Only Xylobanus crossed the Makassar Strait to Sulawesi and does not occur further to the east. The current distribution of Metriorrhynchini is a result of drifting on continental fragments and over-sea dispersal events limited to a few hundreds of kilometers. We conclude that: (1) Afrotropical and Madagascar lineages originated independently from dispersal events during India''s drift to the north and the Mozambique Channel completely isolates the respective faunas since then; (2) Oriental fauna is a recently established mixture of the Indian and Australian lineages, with predominance of the older Indian clades; (3) The fauna of islands located north of Australia colonized Sulawesi after collision with the Sundaland margin and the species rich Australian lineages did not reach Western Wallacea or the Philippines. Our results suggest an impact of subtle differences in biological characteristics on biogeographic history of individual lineages, when mostly lowland and flower-visiting lineages were able to disperse across sea channels.     

Some structures in Azolla megaspores,and an anomalous form

On the assumption that the “float” apparatus of Azolla arose by the “capture” and retention of separate floats developed as massulae round abortive megaspores, a model is proposed, accounting hypothetically for the separate origin of three-floated, nine-floated, fifteen-floated and twenty-four-floated species in different types of cytological behaviour during origin of the functional megaspore. It is considered irrelevant to ask whether nine-floated arose from three-floated or vice versa. Each type arose de novo and possibly more than once, out of the initial cytological situation which is constant for all species.An abnormal form of Azolla imbricata is described, which in terms of the model appears to represent a reversion to a Salvinia-like ancestral form, by loss of linked genes responsible for the Azolla “syndrome”.Anatomical and morphological studies on five modern and two Paleocene species are used to illustrate adaptation of perine as float-retaining mechanisms. A new structure, the manicula, produced from the perispore, is described in A. teschiana and A. velus.     

West to east dispersal and subsequent rapid diversification of the mega‐diverse genus Begonia (Begoniaceae) in the Malesian archipelago

Aim The complex palaeogeography of the Malesian archipelago, characterized by the evolution of an ever‐changing mosaic of terrestrial and marine areas throughout the Cenozoic, provides the geographic backdrop for the remarkable diversification of Malesian Begonia (> 450 species). This study aimed to investigate the origin of Malesian Begonia, the directionality of dispersal events within the Malesian archipelago and the impact of ancient water gaps on colonization patterns, and to identify drivers of diversification. Location Asia, Southeast Asia, Malesia. Methods Plastid DNA sequence data of representatives of all families of the Cucurbitales and Fagales (matK, rbcL, trnL intron, trnL–F spacer, 4076 aligned positions, 92 taxa) and a sample of all major Asian Begonia sections (ndhA intron, ndhF–rpl32 spacer, rpl32–trnL spacer, 4059 aligned positions, 112 taxa) were analysed under an uncorrelated‐rates relaxed molecular clock model to estimate the age of the Begonia crown group divergence and divergence ages within Asian Begonia. Ancestral areas were reconstructed using a likelihood approach implementing a dispersal–extinction–cladogenesis model, and with a Bayesian approach to dispersal–vicariance analysis. Results The results indicated an initial diversification of Asian Begonia in continental Asia in the Miocene, and subsequent colonization of Malesia by multiple lineages. There was support for at least six independent dispersal events from continental Asia and western Malesia to Wallacea dating from the late Miocene to the Pleistocene. Begonia section Petermannia (> 270 species) originated in Western Malesia, and subsequently dispersed to Wallacea, New Guinea and the Philippines. Lineages within this section diversified rapidly since the Pliocene, coinciding with rapid orogenesis on Sulawesi and New Guinea. Main conclusions The predominant trend of Begonia dispersals between continental Asia and Malesia, and also within Malesia, has been from west to east. The water bodies separating the Sunda Shelf region from Wallacea have been porous barriers to dispersal in Begonia following the emergence of substantial land in eastern Malesia from the late Miocene onwards. We hypothesize two major drivers of the diversification of Malesian Begonia: (1) the formation of topographical heterogeneity and the promotion of microallopatry by orogenesis in the Pliocene and Pleistocene; and (2) cyclic vicariance by frequent habitat fragmentations and amalgamations due to climate and sea‐level fluctuations during the Pleistocene.     

Minichromosomes inDrosophila melanogaster derived from the transposing elementTE1

A minichromosome has originated from the transposing elementTE1. This autonomously replicating chromosome contains the structural genes white and roughest, from theDrosophila X chromosome. It arose within a stock carryingTE1 at 45F on chromosome2. In addition to thew andrst genes, the minichromosome may carry section 45C–45F from chromosome2. It is inherited by 33%–47% of the offspring. By this criterion it carries a centromere, although the origin of the centromere is unknown. From this minichromosome a still smaller one has originated, probably through the loss of all material from chromosome2 together with some heterochromatin. At the same time a duplication of white and roughest could have taken place. This chromosome has a strange morphology and is more frequently lost in meiosis than the larger one, but is still transmitted to about 29%–37% of the progeny of one parent heterozygous for the minichromosome. In both cases the flies have variegated eyes, probably as a result of position-effect variegation. The variegation pattern is influenced by factors in theX chromosome. The size of the smaller minichromosome is little more than 1 Mb as determined by pulsed field gel electrophoresis.     

Establishment patterns of non-native insects in New Zealand

Insects comprise the majority of non-native animal species established around the world. However, geographic biases in knowledge hamper an overall understanding of biological invasions globally. A dataset of accidentally introduced non-native insect species established in New Zealand was compiled from databases, entomological literature, and examination of specimens in the New Zealand Arthropod Collection. For each non-native species, the first recorded location and first recorded date of detection was obtained. Excluding intentionally introduced species, there are 1477 non-native insect species successfully established in New Zealand across 16 orders, 234 families and 1017 genera. Four orders (Coleoptera, Hemiptera, Hymenoptera and Diptera) contributed 77.5% of all established insect species. Herbivores represented the largest feeding guild (47.7%), comprised of polyphagous (48.3%) or oligophagous (39.7%) species. The majority of these species originated in the Australasian (36.7%) and Palearctic regions (24.8%). Regression trees, using a binary recursive partitioning approach, found the number of international tourist arrivals, exotic vegetation cover, and regional gross domestic product were the main factors explaining spatial patterns of recently established species. Gross domestic product best explained temporal patterns of establishment over the last century. Our findings demonstrate that broad-scale analyses of non-native species have important applications for border biosecurity by providing insight into the extent of invasions. In New Zealand, the current trajectory indicates fewer non-native species are establishing annually, suggesting biosecurity efforts are being effective at reducing rates of establishment.     

INFORMATION ON NEW GUINEAN KINGFISHERS, ALCEDINIDAE

Additional information on 15 species of New Guinea kingfishers is presented: Alcedo atthis (range, habitat), A. azurea and A. pusilla (ecological separation), Ceyx lepidus (foraging, habitat), Melidora macrorhina (affinities, nocturnal habit), Clytoceyx rex (foraging), Dacelo leachii superflua (treehole nesting), D. tyro (reactions with D. leachii), D. gaudichaud (social organization, antiphonal calling, territory size, habitat), Halcyon torotoro (feeding, defence display), H. nigrocyanea (habitat), H. macleayii and H. sancta (habitat, wintering territory), Tanysiptera dana (habitat), T. Sylvia (distribution of resident and migratory subspecies). Possible ecological separating mechanisms are suggested for the kingfisher community of rainforests. Abundance at one lowland site is discussed.     

The altitudinal and geographical distributions of flower types in Rhododendron section Vireya, especially in the Papuasian species, and the& significance

Most species of Rhododendron section Vireya from Papuasia can be assigned to well-marked flower types, 127 species being placed in five of these types. It is suggested that two of the main types may be pollinated mainly by birds, one by sphingid moths and one by butterflies. Above 3000 m red-flowered species greatly predominate over those with other colours in Papuasia, and also through much of Malesia; the relationship between ornithophily and this correlation is discussed. The distribution of flower types within supraspecific taxa suggests that some rearrangement of the latter may be necessary; some flower types are demonstrably polyphyletic. It is shown that in west Malesia species with flower colour other than red, not or slightly zygomorphic flowers and relatively longer corolla lobes are commoner than within Papuasia; it appears that section Viveya is, florally at least, most specialized in this latter area. Flower type and pollinators in section Vireya are related to those in the rest of the genus, and it is suggested that the adoption of ornithophily has been an important factor in the success of the Ericaceae as a whole in tropical montane areas.     

Recent emergence and worldwide spread of the red tomato spider mite, <Emphasis Type="Italic">Tetranychus evansi</Emphasis>: genetic variation and multiple cryptic invasions

Plant biosecurity is increasingly challenged by emerging crop pests. The spider mite Tetranychus evansi has recently emerged as a new threat to solanaceous crops in Africa and the Mediterranean basin, with invasions characterized by a high reproductive output and an ability to withstand a wide range of temperatures. Mitochondrial (868 bp of COI) and nuclear (1,137 bp of ITS) loci were analyzed in T. evansi samples spanning the current geographical distribution to study the earliest stages of the invasive process. The two sets of markers separate the samples into two main clades that are only present together in South America and Southern Europe. The highest COI diversity was found in South America, consistent with the hypothesis of a South American origin of T. evansi. Among the invaded areas, the Mediterranean region displayed a high level of genetic diversity similar to that present in South America, that is likely the result of multiple colonization events. The invasions of Africa and Asia by T. evansi are characterized by a low genetic variation associated with distinct introductions. Genetic data demonstrate two different patterns of invasions: (1) populations in the Mediterranean basin that are a result of multiple cryptic introductions and (2) emerging invasions of Africa and Asia, each likely the result of propagules from one or limited sources. The recent invasions of T. evansi illustrate not only the importance of human activities in the spread of agricultural pests, but also the limits of international quarantine procedures, particularly for cryptic invasions.