https://www.cell.com/current-biology/pdf/S0960-9822(12)01138-4.pdf

The magnitude of global marine species diversity

Missing link

https://science.sciencemag.org/content/sci/49/1263/265.3.full.pdf

British Antarctic "Terra Nova" Expedition, 1910

http://www.juanjunoy.info/wp-content/uploads/2011/11/Andrade-et-al-2011-Cladistics.pdf

Disentangling ribbon worm relationships: multi‐locus analysis supports traditional classification of the phylum Nemertea

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, histones H3 and H4, and mitochondrial 16S rRNA and COI) for 133 terminals, with particular emphasis on the problematic families Hubrechtidae and Plectonemertidae. Three different datasets were used for phylogenetic analyses and both maximum likelihood and maximum parsimony methodologies were applied. All but one of the resulting tree topologies agree on the paraphyly of the class Palaeonemertea, whereas Heteronemertea, Hoplonemertea, Polystilifera, Monostilifera and Hubrechtidae are always recovered as reciprocally monophyletic. Hubrechtidae is sister group to Heteronemertea (the Pilidiophora hypothesis) only when length variable regions of 18S rRNA and 28S rRNA are excluded. Moreover, the terrestrial and freshwater family Plectonemertidae is recovered with high support and the implications of this finding are further discussed. Finally, we evaluate the utility of DNA barcoding for specimen identification within Nemertea using an extended dataset containing 394 COI sequences. Results suggest that DNA barcoding may work for Nemertea, insofar as a distinctbarcodinggap(thegapbetweenthemaximumintraspecificvariationandtheminimuminterspecificdivergence)may exist, but its recognition is regularly hampered by low accuracy in species level identifications. Additional keywords: cytochrome c oxidase subunit I, Hubrechtidae, Plectonemertidae, Pilidiophora.

/pdf/new-insights-into-the-phylogeny-systematics-and-dna-41igm2e7hp.pdf

New Insights into the Phylogeny, Systematics and DNA Barcoding of Nemertea

Checklist of Nemertean Genera and Species Published between 1995 and 2007

A cladistic analysis was performed on 21 previously described and putative new genera comprising all hoplonemerteans having both monostilifery and interwoven rhynchocoel musculature. Traditional taxonomic methods have placed these genera into two existing families and one putative new family, but there has been active debate as to relationships within and between these groups. Sixty-one characters were employed. The intent of this study was to further elucidate relationships within and between these groups but without addressing their possible positions in the higher taxonomic scheme. The results suggest that the family Plectonemertidae (sensu Moore & Gibson, 1988) and the family Cratenemertidae are paraphyletic as is a new Antarctic form which appears to constitute a monotypic family. The results further suggest that Plectonemertes represents a monotypic family, the five `Group 2' terrestrial genera (Acteonemertes, Argonemertes, Antiponemertes, Leptonemertes and Katechonemertes) form a distinct family, and the freshwater genera Campbellonemertes and Potamonemertes represent either a single distinct family or two monotypic families. The family Cratenemertidae is seen as containing three subfamilies. The analysis also indicates that these groups, in which 10 of the 21 genera are highly habitat-adapted, exhibit no greater homoplasy than is evident in the animal and plant kingdoms generally. Formal designation and naming of the new family group entities suggested here must await publication of original descriptions or redescriptions of the underlying species and genera.

A cladistic view of the Monostilifera (Hoplonemertea) with interwoven rhynchocoel musculature: a preliminary assessment

Yamaoka (1939, 1940a,b) described eight new species of nemerteans found in or near Japan Several other new species he discovered remained in manuscript form until brief descriptions of Emplectonema mitsuii, Paranemertes katoi, Amphiporus ogumai, and Prostoma roseocephalum (now Tetrastemma roseocephalum) appeared, somewhat irregularly, in a faunal encyclopedia in 1947 The authors here present the case for recognizing the validity and availability of these species names and for their correct attribution and date More complete English language descriptions for the four species, from the original Yamaoka manuscript, are included and are augmented by Yamaoka's original illustrations One of the species, Amphiporus ogumai, is transferred to the family Cratenemertidae as Nipponnemertes ogumai comb n

The status of four Japanese nemertean species of Yamaoka

A century ago Burger described the species Drepanophorus valdiviae from a single specimen taken from 155 m off the southern tip of Africa by the research vessel Valdivia during the German Deep Sea Expedition. Stiasny-Wijnhoff in 1923 transferred this species along with Amphiporus stannii (sensu Burger 1895) to a new genus Valdivianemertes but did not mention a family affiliation. In 1993 Crandall transferred this genus to the family Cratenemertidae. During the Spanish Antarctic Expedition BENTART 2003, carried out on board the RV Hesperides, we found one specimen identified with certainty as Valdivianemertes valdiviae, at 602 m depth in the Bellingshausen Sea (Antarctica). As there is no extant holotype, we here redescribe this species from this new specimen and designate it the neotype of this species; photomicrographs of the different regions of the body and the proboscis structure are provided for the first time.

Redescription of Valdivianemertes valdiviae (Bürger, 1909) (Nemertea: Hoplonemertea: Cratenemertidae) and designation of neotype

Four species (in three genera) of the family Cratenemertidae are found in the epipelagic (depth: <300 m) habitat. These species share many morphological differences from the benthic and intertidal majority of cratenemertids: the change in habitat (and, consequently, in lifestyle) can account for some, but not all, of these differences. The organ systems most affected are the body wall, musculature and sensory structures, particularly, the proboscis apparatus and alimentary canal, where the modifications can be attributed to a shift from active predation to passive feeding.

Frank B. Crandall

Papers

Checklist of Nemertean Genera and Species Published between 1995 and 2007

A cladistic view of the Monostilifera (Hoplonemertea) with interwoven rhynchocoel musculature: a preliminary assessment

The status of four Japanese nemertean species of Yamaoka

Redescription of Valdivianemertes valdiviae (Bürger, 1909) (Nemertea: Hoplonemertea: Cratenemertidae) and designation of neotype

Morphological adaptations of the Cratenemertidae (Nemertea, Enopla, Hoplonemertea) to the epipelagic habitat and lifestyle