Sebastian Kvist

Swedish Museum of Natural History

Similarly to other strict blood feeders, leeches from the Haementeria genus (Hirudinida: Glossiphoniidae) have established a symbiotic association with bacteria harbored intracellularly in esophageal bacteriomes. Previous genome sequence analyses of these endosymbionts revealed co-divergence with their hosts, a strong genome reduction, and a simpli...

Similarly to other strict blood-feeders, leeches from the Haementeria genus (Hirudinida: Glossiphoniidae) have established a symbiotic association with bacteria harboured intracellularly in oesophageal bacteriomes. Previous genome sequence analyses of these endosymbionts revealed co-divergence with their hosts, a strong genome reduction, and a simp...

Strict blood-feeding animals are confronted with a strong B vitamin de_ciency. Blood-feeding leeches from the Glossiphoniidae family, similarly to haematophagous insects, have evolved specialised organs called bacteriomes to harbour symbiotic bacteria. Leeches of the Haementeria genus have two pairs of globular bacteriomes attached to the oesophagu...

Background Herein, we describe a new species of turtle blood-feeding leech, Placobdella nabeulensis sp. nov. from Palearctic North Africa (Tunisia and Algeria). The new species is described based on detailed morphological analyses using light and scanning electron microscopes. Results Apart from the detailed morphology of the atrium, morphological...

Herein, we describe a new species of turtle blood-feeding leech, Placobdella nabeulensis sp. nov. from Palearctic North Africa (Tunisia and Algeria). The new species is described based on detailed morphological analyses using light and scanning electron microscopes. Apart from the detailed morphology of the atrium, morphological features alone do n...

Strict blood-feeding animals are confronted with a strong B vitamin deficiency. Leeches from the Glossiphoniidae family, notably species of Placobdella, Placobdelloides, and Haementeria are regarded as strict blood-feeders, and similarly to blood-feeding insects, have evolved specialised organs called bacteriomes to harbour symbiotic bacteria. Leec...

Integration of the world's natural history collections can provide a resource for decision-makers.

Over the past three centuries, people have collected objects and specimens and placed them in natural history museums throughout the world. Taken as a whole, this global collection is the physical basis for our understanding of the natural world and our place in it, an unparalleled source of information that is directly relevant to issues as divers...

i>Theromyzon Philippi, 1867 is a genus of sanguivorous, freshwater leeches in the family Glossiphoniidae. The genus is broadly distributed across the globe, possibly due to the frequent feeding in the nasopharyngeal cavities of migratory waterfowl that may allow for long distance dispersal. The genus has a history of taxonomic confusion resulting f...

The Holarctic leech genus Haemopis currently includes 11 species, all of which are macrophagous, as opposed to their more infamous bloodfeeding counterparts among hirudiniform leeches. In spite of their ecological importance as fish food and predators of freshwater invertebrates, there is a paucity of data regarding morphology and genetic variation...

The bloodfeeding leech genus Placobdella is dominated by North American diversity, with only a single nominal species known from Central America and one from the Palearctic region. This is likely due to considerable underestimation of Palearctic biodiversity, but investigations into potential hidden diversity are lacking. To shed light on this, the...

Leeches play important roles in food webs due to their abundance, diversity and feeding habits. Studies using invertebrate‐derived DNA (iDNA) extracted from leech gut contents to target vertebrate DNA have focused on the Indo‐Pacific region and mainly leveraged the leech family Haemadipsidae, composed of bloodfeeding terrestrial leeches, while pred...

Some species of leeches migrate into waterfowl nests and use these both as general habitats and to deposit cocoons, but ecological associations between leeches and birds are not well understood. In the present study, characteristics of waterfowl nests both as living area for leeches (Hirudinea) and as reproduction areas for select hirudinid leeches...

Leeches play important roles in food webs due to their abundance, diversity and feeding habits. Studies using invertebrate-derived DNA (iDNA) extracted from leech gut contents to target vertebrate DNA have focused on the Indo-Pacific region and mainly leveraged the leech family Haemadipsidae, composed of haematophagous terrestrial leeches, while th...

Bloodfeeding is employed by many parasitic animals and requires specific innovations for efficient feeding. Some of these innovations are molecular features that are related to the inhibition of hemostasis. For example, bloodfeeding insects, bats and leeches release proteins with anticoagulatory activity through their salivary secretions. The antis...

In October of 2018, Canada Border Services Agency (CBSA) at Pearson International Airport in Toronto notified the Wildlife Enforcement Branch of Environment and Climate Change Canada that a passenger had arrived aboard a flight from Russia with a large quantity of live leeches. The leeches had been discovered in the passenger's carry-on luggage. An...

Here, we present the mitogenome of the blood feeding leech Haementeria acuecueyetzin (Hirudinida: Glossiphoniidae) based on specimens collected in Tabasco, Mexico. The circular genome is 14,985 bp in length, and consists of 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and an AT-rich control region. Phylogenetic analysis based on the 13 p...

In the embryonic blast cells of leeches, segmental identity is conferred in a cell-intrinsic manner (i.e., with temporal rather than spatial signals), at or shortly after the birth of the cell. If these blast cells are destroyed in only one of the two germinal bandlets that form the ventral midline, this can result in segment-specific features that...

The European medicinal leech has been used for medicinal purposes for millennia, and continues to be used today in modern hospital settings. Its utility is granted by the extremely potent anticoagulation factors that the leech secretes into the incision wound during feeding and, although a handful of studies have targeted certain anticoagulants, th...

With few exceptions, animal mitochondrial genomes are impressively conserved with regard to gene arrangement (synteny). For certain taxonomic groups, specific genomic “hotspot” regions present high levels of gene rearrangements. This is the case for the region between the mitochondrial genes cox2 and atp8 across Annelida, particularly in members of...

Blood-feeding leeches of the genus Placobdella have acquired intracellular alphaproteobacterial endosymbionts of the genus Reichenowia that potentially aid in the production of B vitamins, thereby ameliorating the lack of these essential nutrients in the diet of the hosts. For Placobdella associates, little is still known about the diversity, genet...

The description of Helobdella stagnalis (Linnaeus, 1758) has emphasized the presence of a nuchal, chitinous scute located on the dorsal surface in the first third of the body as the diagnostic character for the species. Historically, identifications of species of Helobdella have relied heavily on this character and, as a result, Helobdella stagnali...

A new species of medicinal leech, Macrobdella mimicus n. sp., is described from specimens collected in Maryland; this is the first description of a North American macrobdellid since 1975. Superficially, the new species resembles the well-known Macrobdella decora, as both species possess 4 accessory pores arranged symmetrically on the ventral surfac...

Placobdella rugosa has long presented challenges to leech biologists. Its extreme morphological variability and similarity to some congeneric species has confounded classification for over a century. Recent molecular analyses revealed a surprising lack of genetic variation among morphologically disparate, geographically widespread specimens of P. r...

Bloodfeeding requires several adaptations that allow the parasite to feed efficiently. Leeches and other hematophagous animals have developed different mechanisms to inhibit hemostasis, one of the main barriers imposed by their hosts. Limnobdella mexicana is a member of the leech family Praobdellidae, a family of host generalists known for their pr...

The medicinal utility of leeches has been demonstrated through decades of use in modern hospital settings, mainly as relievers of venous congestion following flap or digit replantation surgery. In the present study, we sequence and annotate (through BLAST‐ and Gene Ontology‐based approaches) the salivary transcriptome of the nonblood feeding hirudi...

Historically, there has been much confusion surrounding the identity and separation of European and North American species of Glossiphonia (Annelida: Clitellata: Glossiphoniidae). Using cytochrome c oxidase subunit I (COI) sequences from newly collected specimens of Glossiphonia complanata and Glossiphonia elegans from a broad geographic range cove...

We report two new, curious records of freshwater worms collected in the Panama Canal, Panama: the ribbon worm, Apatronemertes albimaculosa Wilfert and Gibson, 1974, and the leech, Placobdella parasitica (Say, 1824). Identification of these specimens relied on morphological examinations and, more heavily, on molecular barcoding using the mitochondri...

We evaluated the extent of intraspecific and interspecific genetic distances for two highly diverse infraorders of Odonata: Anisoptera and Zygoptera. All cytochrome c oxidase subunit I sequences (cox1), the region chosen for zoological DNA barcoding, present in GenBank for each infraorder were downloaded and curated. For Anisoptera, the final datas...

Leeches (Annelida: Hirudinea) possess powerful salivary anticoagulants and, accordingly, are frequently employed in modern, authoritative medicine. Members of the almost exclusively marine family Piscicolidae account for 20% of leech species diversity, and feed on host groups (e.g., sharks) not encountered by their freshwater and terrestrial counte...

Leeches have a worldwide distribution, yet numerous geographical regions remain to be adequately surveyed. Here, we present leech species records for one of these regions: the far north of Ontario, Canada. This region is primarily wetland habitat and includes two of Ontario’s three ecozones. Morphological examinations, as well as a single instance...

We present a DNA barcoding study of Neotropical odonates from the Upper Plata basin, Brazil. A total of 38 species were collected in a transition region of “Cerrado” and Atlantic Forest, both regarded as biological hotspots, and 130 cytochrome c oxidase subunit I (COI) barcodes were generated for the collected specimens. The distinct gap between in...

Full neighbor-joining tree with BOLD accession numbers following each taxonomic name. (PDF)

Metadata for each of the specimens used for the present study. (XLSX)

Placobdella is a genus of blood-feeding leeches in the family Glossiphoniidae. Historically, species of Placobdella have posed difficulty for systematists owing to a lack of informative morphological characters and the preponderance of inadequate or incomplete species descriptions. Here, we conduct a phylogenetic analysis of 55 individuals represen...

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009;...

This plot is not part of the published stance but derives from it. The plot shows the number of authors by geographic region (courtesy of Dr. Diego Astua).

Invertebrate-derived ingested DNA (iDNA) is quickly proving to be a valuable, non-invasive tool for monitoring vertebrate species of conservation concern. Using the DNA barcoding locus, we successfully identified both the blood-feeding leech Haementeria acuecueyetzin and its blood meal—the latter is shown to be derived from the Caribbean manatee, T...

Although several leech species have recently been screened for anticoagulation factors, piscicolids represent a major gap in our knowledge of the distribution of these proteins across the phylogeny of leeches. Piscicolidae is predominantly a marine family and its members feed on a variety of fish species. The pontobdelline species Pontobdella macro...

Harpellales, an early-diverging fungal lineage, is associated with the digestive tracts of aquatic arthropod hosts. Concurrent with the production and annotation of the first four Harpellales genomes, we discovered that Zancudomyces culisetae, one of the most widely distributed Harpellales species, encodes an insect-like polyubiquitin chain. Ubiqui...

Mitochondrial DNA sequences, often in combination with nuclear markers and morphological data, are frequently used to unravel the phylogenetic relationships, population dynamics and biogeographic histories of a plethora of organisms. The information provided by examining complete mitochondrial genomes also enables investigation of other evolutionar...

Start and stop codons for all 13 protein-coding genes from the mitochondrial genomes of Clitellata. (XLSX)

tRNA structures of Clitellata mitochondrial genomes. tRNA structures of Clitellata tRNA genes as predicted by MITOS and manually curated. At the top of each set of blocks, dendograms showing the phylogenetic relationship of the organisms as calculated in the bayesian phylogenetic reconstruction. At the left of each individual block, the tRNA gene n...

Concatenated alignment including myzostomids. Concatenated amino acid alignment used for phylogenetic reconstruction including myzostomids. The alignment was “cleaned” using Gblocks and is in nexus format. (NEX)

Concatenated alignment excluding myzostomids. Concatenated amino acid alignment used for phylogenetic reconstruction excluding myzostomids. The alignment was “cleaned” using Gblocks and is in nexus format. (NEX)

Accession numbers and taxonomic classification for all mitochondrial genomes used in this study. (XLSX)

General characteristics of putative control regions (pCRs) of mitochondrial genomes of Annelida. (XLSX)

Midpoint-rooted neighbor joining tree derived from the full 915-sequence dataset. The tree was used to guide the separation of lineages for the CAOS analyses of smaller datasets (see text for further details). (PDF)

List of specimens for which COI sequences were newly generated and used in the present study. (XLSX)

Whereas many nemerteans (ribbon worms; phylum Nemertea) can be identified from external characters if observed alive, many are still problematic. When it comes to preserved specimens (as in e.g. marine inventories), there is a particular need for specimen identifier alternatives. Here, we evaluate the utility of COI (cytochrome c oxidase subunit I)...

One of the recalcitrant questions regarding the evolutionary history of clitellate annelids involves the feeding preference of the common ancestor of extant rhynchobdellid (proboscis bearing) and arhynchobdellid (jaw bearing) leeches. Whereas early evidence, based on morphological data, pointed towards independent acquisitions of blood feeding in t...

Recent investigations, based mostly on molecular data, have unraveled the evolutionary history of several common ribbon worm (phylum Nemertea) species and solidified the taxonomic status of many higher taxa within the group. However, a large proportion of enigmatic species have yet to be placed in a phylogenetic framework. We investigated the phylo...

The heteronemertean species Micrura dellechiajei is thus far only known from its type locality in the Gulf of Naples (Italy) and has not been recorded in 120 years. During two oceanographic surveys conducted in Spanish Mediterranean waters, several nemertean specimens were collected, and thorough morphological examination indicated that some of the...

Abstract Accurate identification of unknown specimens by means of DNA barcoding is contingent on the presence of a DNA barcoding gap, among other factors, as its absence may result in dubious specimen identifications - false negatives or positives. Whereas the utility of DNA barcoding would be greatly reduced in the absence of a distinct and suffic...

Namalycastis glasbyi Fernando & Rajasekaran, 2007 was originally described from the creek-lined coast north of Mumbai in western India. However, the original description includes some oddities that make species recognition problematic and may confuse future taxonomic evaluations of the genus. Moreover, the type material of the species has been lost...

Although some clades of ribbon worms (phylum Nemertea) are consistently recovered with high support in molecular phylogenies, the placement and inter-relationships of some taxa have proven problematic. Herein, we performed molecular phylogenetic analyses aimed at resolving these recalcitrant splits, using six loci (nuclear 18S rRNA, 28S rRNA, histo...

Background Although molecular tools are increasingly employed to decipher invertebrate systematics, earthworm (Annelida: Clitellata: ‘Oligochaeta’) taxonomy is still largely based on conventional dissection, resulting in data that are mostly unsuitable for dissemination through online databases. In order to evaluate if micro-computed tomography (μC...

In spite of the high relevance of lumbricid earthworms ('Oligochaeta': Lumbricidae) for soil structure and functioning, the taxonomy of this group of terrestrial invertebrates remains in a quasi-chaotic state. Earthworm taxonomy traditionally relies on the interpretation of external and internal morphological characters, but the acquisition of thes...

Magesh, M., Kvist S. and Glasby, C.J. 2014. Incipient speciation within the Namalycastis abiuma (Annelida: Nereididae) species group from southern India revealed by combined morphological and molecular data. Memoirs of Museum Victoria 71: 169–176. Namalycastis abiuma (Grube, 1872), originally described from Brazil, comprises a species complex of mo...

Freshwater, marine, and terrestrial leeches that depend on a diet of fresh blood have evolved salivary peptide components that inhibit normal thrombus formation by prey. Although bloodfeeding in leeches has long been of interest to biologists and medical practitioners alike, only a few studies have comprehensively examined the anticoagulant reperto...

The functionality of standard zoological DNA barcoding practice (the identification of unknown specimens by comparison of COI sequences) is contingent on working barcode databases with sufficient taxonomic coverage. It has already been established that the main barcoding repositories, NCBI and BOLD, are devoid of data for many animal groups but the...

Although medicinal leeches have long been used as treatment for various ailments because of their potent anticoagulation factors, neither the full diversity of salivary components that inhibit coagulation, nor the evolutionary selection acting on them has been thoroughly investigated. Here, we constructed expressed sequence tag libraries from saliv...

We present phylogenomic analyses of the most comprehensive molecular character set compiled for Annelida and its constitu-ent taxa, including over 347 000 aligned nucleotide sites for 39 taxa. The nucleotide data set was recovered using a pre-existing amino acid data set of almost 48 000 aligned sites as a backbone for tBLASTn searches against NCBI...

Namalycastis jaya sp. n. (Polychaeta: Nereididae: Namanereidinae)is described from the southern coast of Kerala in southwest India. One important characteristic feature of the species is the lack of notochaetae in all parapodia, a characteristic that it shares with at least two other species, Namalycastis elobeyensis Glasby, 1999and Namalycastis ha...

Nematode parasites were encountered in kosher-certified fish meat and roe, and the question was raised as to whether or not these food products were kosher as concerns food preparation standards-a matter that pertains to the identity and, by extension, the life cycle of the parasites. To ascertain the identities of parasitic nematodes, given the di...

The genome of the non-blood-feeding glossiphoniid leech Helobdella robusta was screened for leech antiplatelet protein (LAPP), an anticoagulant that specifically inhibits collagen-stimulated platelet aggregation. Previously identified LAPP sequences from Haementeria officinalis were used as queries against the predicted genes in the genome, employi...

Description of BLASTn Hits Encountered using the Reichenowia parasitica Contigs as Queries Against 50 Selected Bacterial Genomes. All hits matched at 1E-5 or lower. Hit descriptions follow the GenBank annotations for the genes, and the hit-taxon is shown in brackets. (DOC)

List of species used for subtractive scaffolding, orthologue recovery and phylogenetic analysis. Bold font denotes the non-alphaproteobacterial species. GenBank RefSeq refers to the submission inclusive of the entire genome. (DOC)

Although several commensal alphaproteobacteria form close relationships with plant hosts where they aid in (e.g.,) nitrogen fixation and nodulation, only a few inhabit animal hosts. Among these, Reichenowia picta, R. ornata and R. parasitica, are currently the only known mutualistic, alphaproteobacterial endosymbionts to inhabit leeches. These bact...

AbstrAct The oceans are among the most biodiverse of Earth's environments. Introducing students to this diversity in the field provides an opportunity to examine the evolution of animals. We detail how readily a field-based biodiversity and evolution class can be designed and taught in a phyletically diverse marine setting in North America. An unde...

AbSTrACT An assessment of the hirudinifauna of Washington State is presented. in total, 11 distinct leech species were found representing two new records for the state and two new species of the genus Placobdella, both described herein. Placobdella kwetlumye, n. sp., and Placobdella sophieae, n. sp., both collected in Squires Lake, Whatcom County,...

Species identifications based on DNA barcoding rely on the correct identity of previously barcoded specimens, but little attention has been given to whether deposited barcodes include correspondence to the species' name-bearing type. The information content associated with COX1 sequences in the two most commonly used repositories of barcodes, GenBa...

Prior attempts to resolve the phylogenetic relationships of the cosmopolitan, marine clitellate genus Tubificoides, using only morphology, resulted in unresolved trees. In this study, three mitochondrial and three nuclear loci (5912 aligned sites) were analyzed, representing 14 morphologically separate species. Genetic distances within and between...

Tubificoides blakei and T. methanicus, both new species of oligochaetes, are described from 2156 and 2170 m depth on the Blake Ridge Diapir, near the intersection of the Carolina Rise and the Blake Ridge, off the continental shelf of North and South Carolina (U.S.A. East Coast). Tubificoides blakei is characterized by the long, parallel teeth of it...