Reconstructing the phylogeny of the Sipuncula

Sipunculans are marine spiralian worms with possible close affinities to the Mollusca or Annelida. Currently 147 species, 17 genera, 6 families, 4 orders and 2 classes are recognized. In this paper we review sipunculan morphology, anatomy, paleontological data and historical affiliations. We have conducted cladistic analyses for two data sets to elucidate the phylogenetic relationships among sipunculan species. We first analyzed the relationships among the 45 species of Phascolosomatidea with representatives of the Sipunculidea as outgroups, using 35 morphological characters. The resulting consensus tree has low resolution and branch support is low for most branches. The second analysis was based on DNA sequence data from two nuclear ribosomal genes (18S rRNA and 28S rRNA) and one nuclear protein-coding gene, histone H3. Outgroups were chosen among representative spiralians. In a third analysis, the molecular data were combined with the morphological data. Data were analyzed using parsimony as the optimality criterion and branch support evaluated with jackknifing and Bremer support values. Branch support for outgroup relationships is low but the monophyly of the Sipuncula is well supported. Within Sipuncula, the monophyly of the two major groups, Phascolosomatidea and Sipunculidea is not confirmed. Of the currently recognized families, only Themistidae appears monophyletic. The Aspidosiphonidae, Phascolosomatidae and Golfingiidae would be monophyletic with some adjustments in their definition. The Sipunculidae is clearly polyphyletic, with Sipunculus nudus as the sister group to the remaining Sipuncula, Siphonosoma cumanense the sister group to a clade containing Siphonosoma vastumand the Phascolosomatidea, and Phascolopsis gouldi grouping within the Golfingiiformes, as suggested previously by some authors. Of the genera with multiple representatives, only Phascolosoma and Themiste are monophyletic as currently defined. We are aiming to expand our current dataset with more species in our molecular database and more detailed morphological studies.     

An integrative approach to species delimitation in Benthomangelia (Mollusca: Conoidea)

DNA sequences are currently used to propose primary hypotheses of species delimitation, especially when morphological variability is difficult to assess. In an integrative taxonomy framework, these hypotheses are then compared with other characters, such as morphology or geography, to produce robust species delimitations. For this purpose, the cytochrome oxidase subunit I (COI) gene has been sequenced for almost 50 specimens of the genus Benthomangelia , a deep-sea marine gastropod genus, collected in the South-West Pacific. Five genetic groups, displaying low and high genetic distances respectively within and between groups, were defined. COI hypotheses were compared with both the results obtained with the independent nuclear 28S gene and with an elliptic Fourier analysis of the shape of the last whorl of the shell. 28S gene analysis confirmed the same well-supported groups as COI, and elliptic Fourier analysis identified several morphological characters that vary similarly to genetic variability.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 96 , 696–708.     

Evolutionary relationships within the protostome phylum Sipuncula: a molecular analysis of ribosomal genes and histone H3 sequence data

The phylogenetic relationships of the members of the phylum Sipuncula are investigated by means of DNA sequence data from three nuclear markers, two ribosomal genes (18S rRNA and the D3 expansion fragment of 28S rRNA), and one protein-coding gene, histone H3. Phylogenetic analysis via direct optimization of DNA sequence data using parsimony as optimality criterion is executed for 12 combinations of parameter sets accounting for different indel costs and transversion/transition cost ratios in a sensitivity analysis framework. Alternative outgroup analyses are also performed to test whether they affected rooting of the sipunculan topology. Nodal support is measured by parsimony jackknifing and Bremer support values. Results from the different partitions are highly congruent, and the combined analysis for the parameter set that minimizes overall incongruence supports monophyly of Sipuncula, but nonmonophyly of several higher taxa recognized for the phylum. Mostly responsible for this is the split of the family Sipunculidae in three main lineages, with the genus Sipunculus being the sister group to the remaining sipunculans, the genus Phascolopsis nesting within the Golfingiiformes, and the genus Siphonosoma being associated to the Phascolosomatidea. Other interesting results are the position of Phascolion within Golfingiidae and the position of Antillesoma within Aspidosiphonidae. These results are not affected by the loci selected or by the outgroup chosen. The position of Apionsoma is discussed, although more data would be needed to better ascertain its phylogenetic affinities. Monophyly of the genera with multiple representatives (Themiste, Aspidosiphon, and Phascolosoma) is well supported, but not the monophyly of the genera Nephasoma or Golfingia. Interesting phylogeographic questions arise from analysis of multiple representatives of a few species.     

Adding mitochondrial sequence data (16S rRNA and cytochrome c oxidase subunit I) to the phylogeny of centipedes (Myriapoda: Chilopoda): an analysis of morphology and four molecular loci

Relationships within Chilopoda (centipedes) are assessed based on 222 morphological characters, complete 18S rRNA sequences for 70 chilopod terminals, the D3 region of 28S rRNA for 65 terminals, 16S rRNA sequences for 54 terminals and cytochrome c oxidase subunit I sequences for 45 terminals. Morphological and molecular data for seven orders of Diplopoda are used to root cladograms for Chilopoda. Analyses use direct character optimization for 15 gap and substitution models. The Pleurostigmophora and Epimorpha s.l. hypotheses are largely stable to parameter variation for the combined data; the latter clade is formalized as the new taxon Phylactometria. The combined data include parameter sets that support either the monophyly of Epimorpha s.str. (=Scolopendromorpha + Geophilomorpha) or Craterostigmus + Geophilomorpha; the former derives its support from morphology and the nuclear ribosomal genes. Monophyly of Lithobiomorpha and the sister group relationship between Lithobiidae and Henicopidae are stable for morphological and combined data, and are also resolved for the molecular data for 14 of 15 parameter sets. The fundamental split in Scolopendromorpha is between Cryptopidae and Scolopendridae sensu Attems. Blind scolopendromorphs unite as a clade in most molecular and combined analyses, including those that minimize incongruence between data partitions. Geophilomorpha divides into Placodesmata and Adesmata under nine of 15 explored parameter sets.     

Species diversity of Onchidiidae (Eupulmonata: Heterobranchia) on the mainland of China based on molecular data

The identification of members of the Onchidiidae is based on morphological characters; this is often time-consuming and can be inconclusive. In order to explore the species diversity of onchidiids in China, we provide a phylogeny constructed using partial sequences of two mitochondrial genes (16S rRNA and COI) and one nuclear ribosomal RNA gene (28S rRNA) from 32 samples comprising five genera. The topology, using both Bayesian and Maximum Likelihood inference methods, showed that the taxa clustered in two main groups of six species, one of which included Platevindex mortoni, Platevindex sp. and Onchidium ‘struma’; the other included Paraoncidium reevesii, Onchidella sp. and Peronia verruculata. It is clear that COI will be useful in discriminating onchidiid species-group taxa.     

Molecular phylogenetics of Triculine snails (Gastropoda: Pomatiopsidae) from southern China

Triculine (Gastropoda: Rissooidea: Pomatiopsidae) snails are involved in the transmission of schistosomiasis and paragonimiasis; their distributions are mainly across southeastern Asia and southern China. In the present investigation, partial sequences of COI, 16S, and 28S were examined to infer the phylogenetic relationships among the species rich and poorly understood gastropod. Samples were collected from 12 geographic locations in six provinces of southern China. Several methods such as maximum parsimony, maximum likelihood and distance analysis were used in phylogenetic analyses among these taxa. The resultant phylogenetic trees showed a similar topology irrespective of the phylogenetic methods used. The taxa fell into two clades, with those from Fujian, Guangxi, and Zhejiang Provinces in one clade and those from Hunan, Sichuan and Hubei in the other. Among the taxa in Hubei Province, five formed a monophyletic clade, but Tricula sp. H-SHY fell into a sister clade of Tricula hortensis of Sichuan, whilst Tricula hongshanensis formed a single clade. Sister taxa Tricula pingi and Tricula hsiangi formed well-supported clade within almost all the trees. These results, while preliminary, represent the first attempt to reconstruct a phylogeny for Triculinae across China.     

A molecular framework for the phylogeny of the Pseudocerotidae (Platyhelminthes,Polycladida)

Systematic relationships within the cotylean family Pseudocerotidae were examined using nucleotide sequences of the D3 expansion segment of the 28S rDNA gene. A previously suggested separation of Pseudoceros and Pseudobiceros based on the number of male reproductive systems was confirmed. Regardless of the algorithm employed, Pseudoceros always formed a monophyletic clade. Pseudobiceros appeared to be paraphyletic; however, a constrained maximum parsimony tree was not significantly longer (2 steps, = 0.05). Additionally, the genera Maiazoon, Phrikoceros and Tytthosoceros were validated as taxonomic entities, and their relationships to other genera within the family were determined. Molecular data also supported species separations based on colour patterns. An intraspecific genetic distance of 1.14% was found for Pseudoceros bifurcus, whereas the intrageneric distance was 3.58%. Genetic distances among genera varied, with the closest distance being 2.048% between Pseudobiceros and Maiazoon, and the largest distance (8.345%) between Pseudoceros and Tytthosoceros.     

Molecular phylogeny of the higher taxa of Odonata (Insecta) inferred from COI, 16S rRNA, 28S rRNA,and EF1‐α sequences

In this study, we sequenced both two mitochondrial genes (COI and 16S rRNA) and nuclear genes (28S rRNA and elongation factor‐1α) from 71 species of Odonata that represent 7 superfamilies in 3 suborders. Phylogenetic testing for each two concatenated gene sequences based on function (ribosomal vs protein‐coding genes) and origin (mitochondrial vs nuclear genes) proved limited resolution. Thus, four concatenated sequences were utilized to test the previous phylogenetic hypotheses of higher taxa of Odonata via Bayesian inference (BI) and maximum likelihood (ML) algorithms, along with the data partition by the BI method. As a result, three slightly different topologies were obtained, but the BI tree without partition was slightly better supported by the topological test. This topology supported the suborders Anisoptera and Zygoptera each being a monophyly, and the close relationship of Anisozygoptera to Anisoptera. All the families represented by multiple taxa in both Anisoptera and Zygoptera were consistently revealed to each be a monophyly with the highest nodal support. Unlike consistent and robust familial relationships in Zygoptera those of Anisoptera were partially unresolved, presenting the following relationships: ((((Libellulidae + Corduliidae) + Macromiidae) + Gomphidae + Aeshnidae) + Anisozygoptera) + (((Coenagrionidae + Platycnemdidae) + Calopterygidae) + Lestidae). The subfamily Sympetrinae, represented by three genera in the anisopteran family Libellulidae, was not monophyletic, dividing Crocothemis and Deielia in one group together with other subfamilies and Sympetrum in another independent group.     

基于28S rRNA D2序列的内茧蜂亚科的分子系统发育

首次利用同源28S rRNA D2基因序列对内茧蜂亚科Rogadinae （昆虫纲Insecta：膜翅目Hymenoptera：茧蜂科Braconidae）进行了分子系统学研究。本研究从95%～100%乙醇浸渍保存的标本中提取基因组DNA并扩增了10种内群种类和5种外群种类的28S rDNA D2片段并测序（GenBank序列号AY167645-AY167659）,利用BLAST搜索相关的同源序列, 采用了GenBank中13个种类的28S rRNA D2同源序列,然后据此进行分子分析。利用3个外群（共8个种类）和3种建树方法 (距离邻近法distance based neighbor joining, NJ; 最大俭约法maximum parsimony, MP; 和最大似然法maximum likelihood, ML)分析了内茧蜂亚科内的分子系统发育关系。结果表明,由分子数据产生的不同的分子系统树均显示内茧蜂亚科是一个单系群。内茧蜂亚科内依据形态和生物学特征的分群（族和亚族）及其系统发育关系得到部分支持。NJ、MP和ML分析结果均表明内茧蜂族Rogadini不是一个单系,而是一个并系,其余3族则得到不同程度的支持。内茧蜂族可分成2个分支：“脊茧蜂属Aleiodes+弓脉茧蜂属Arcaleiodes”和“沟内茧蜂属Canalirogas+锥齿茧蜂属Conspinaria+刺茧蜂属Spinaria+内茧蜂属Rogas”,二者不是姐妹群。脊茧蜂属Aleiodes和弓脉茧蜂属Arcaleiodes始终是姐妹群。脊茧蜂属Aleiodes是一个单系,并可分成2个姐妹分支,这与依据形态和生物学特征的亚属分群相一致。弓脉茧蜂属Arcaleiodes Chen et He,1991是一个独立的属。分支“沟内茧蜂属Canalirogas+锥齿茧蜂属Conspinaria+刺茧蜂属Spinaria+内茧蜂属Rogas”的单系性仅得到部分分子数据的支持;因形态特异（腹部成甲壳状）而列为亚族级的刺茧蜂属Spinaria,分子分析没有证实这一点。横纹茧蜂族Clinocentrini是个单系,并在内茧蜂亚科的系统发育中处于基部（原始）的位置。我们研究结果还表明,阔跗茧蜂属Yelicones和潜蛾茧蜂属Stiropius相对应的阔跗茧蜂族Yeliconini和潜蛾茧蜂族Stiropiini为2个独立的分支, 与形态和生物学的结果一致,但它们在内茧蜂亚科的系统发育的位置不明,有待今后进一步研究。     

Congruence between molecular phylogeny and cuticular design in Echiniscoidea (Tardigrada,Heterotardigrada)

Although morphological characters distinguishing echiniscid genera and species are well understood, the phylogenetic relationships of these taxa are not well established. We thus investigated the phylogeny of Echiniscidae, assessed the monophyly of Echiniscus, and explored the value of cuticular ornamentation as a phylogenetic character within Echiniscus. To do this, DNA was extracted from single individuals for multiple Echiniscus species, and 18S and 28S rRNA gene fragments were sequenced. Each specimen was photographed, and published in an open database prior to DNA extraction, to make morphological evidence available for future inquiries. An updated phylogeny of the class Heterotardigrada is provided, and conflict between the obtained molecular trees and the distribution of dorsal plates among echiniscid genera is highlighted. The monophyly of Echiniscus was corroborated by the data, with the recent genus Diploechiniscus inferred as its sister group, and Testechiniscus as the sister group of this assemblage. Three groups that closely correspond to specific types of cuticular design in Echiniscus have been found with a parsimony network constructed with 18S rRNA data. © 2013 The Linnean Society of London     

基于部分18S rDNA, 28S rDNA和COI基因序列的索科线虫亲缘关系

通过PCR扩增获得我国常见昆虫病原索科线虫6属10种18S rDNA、28S rDNA(D3区)和COI基因序列,结合来自GenBank中6属10种索科线虫的18S rDNA同源序列,用邻接法和最大简约法构建系统进化树。结果显示:12属索科线虫分为三大类群,第一大类群是三种罗索属线虫(Romanomermis)先聚在一起,再与两索属(Amphimermis)和蛛索属(Aranimermis)线虫聚为一支;在第二大类群中,六索属(Hexamermis)、卵索属线虫(Ovomermis)和多索属(Agamermis)亲缘关系最近,先聚在一起,再与八腱索属(Octomyomermis)和Thaumamermis线虫聚为一支。第三大类群由索属(Mermis)和异索属(Allomermis)线虫以显著水平的置信度先聚在一起,再与蠓索属(Heleidomermis)和施特克尔霍夫索属(Strelkovimermis)线虫聚为一支。从遗传距离看,基于3个基因的数据集均显示索科线虫属内种间差异明显小于属间差异,武昌罗索线虫(R.wuchangensis)和食蚊罗索线虫(R.culicivorax)同属蚊幼寄生罗索属线虫,其种间的遗传距离最小。     

Molecular phylogeny of Diplostomum,Tylodelphys, Austrodiplostomum and Paralaria (Digenea: Diplostomidae) necessitates systematic changes and reveals a history of evolutionary host switching events

The Diplostomidae Poirier, 1886 is a large, globally distributed family of digeneans parasitic in intestines of their definitive hosts. Diplostomum and Tylodelphys spp. are broadly distributed, commonly reported, and the most often sequenced diplostomid genera. The majority of published DNA sequences from these genera originated from larval stages only, which typically cannot be identified to the species level based on morphology alone. We generated partial large ribosomal subunit (28S) rRNA and cytochrome c oxidase subunit 1 (cox1) mtDNA gene sequences from 14 species/species-level lineages of Diplostomum, six species/species-level lineages of Tylodelphys, two species/species-level lineages of Austrodiplostomum, one species previously assigned to Paralaria, two species/species-level lineages of Dolichorchis and one unknown diplostomid. Our DNA sequences of 11 species/species-level lineages of Diplostomum (all identified to species), four species/species-level lineages of Tylodelphys (all identified to species), Austrodiplostomum compactum, Paralaria alarioides and Dolichorchis lacombeensis originated from adult specimens. 28S sequences were used for phylogenetic inference to demonstrate the position of Paralaria alarioides and Dolichorchis spp. within the Diplostomoidea and study the interrelationships of Diplostomum, Tylodelphys and Austrodiplostomum. Our results demonstrate that two diplostomids from the North American river otter (P. alarioides and a likely undescribed taxon) belong within Diplostomum. Further, our results demonstrate the non-monophyly of Tylodelphys due to the position of Austrodiplostomum spp., based on our phylogenetic analyses and morphology. Furthermore, the results of phylogenetic analysis of 28S confirmed the status of Dolichorchis as a separate genus. The phylogenies suggest multiple definitive host-switching events (birds to otters and among major avian groups) and a New World origin of Diplostomum and Tylodelphys spp. Our DNA sequences from adult digeneans revealed identities of 10 previously published lineages of Diplostomum and Tylodelphys, which were previously identified to genus only. The novel DNA data from this work provide opportunities for future comparisons of larval diplostomines collected in ecological studies.     

Molecular phylogeny of the nutmeg shells (Neogastropoda, Cancellariidae)

Cancellariidae, or nutmeg shells, is a family of marine gastropods that feed on the body fluids and the egg cases of marine animals. The 300 or so living species are distributed worldwide, mostly on soft bottoms, from intertidal to depths of about 1000 m. Although they are a key group for the understanding of neogastropod evolution, they are still poorly known in terms of anatomy, ecology and systematics. This paper reports the first mitochondrial multi-gene phylogenetic hypothesis for the group. Data were collected for 50 morphospecies, representative of 22 genera belonging to the three currently recognized subfamilies. Sequences from three genes (12S, 16S and COI) were analyzed with Maximum Likelihood analysis and Bayesian Inference, both as single gene datasets and in two partitioned concatenated alignment. Largely consistent topologies were obtained and discussed with respect to the traditional subfamilial arrangements. The obtained phylogenetic trees were also used to produce Robinson-Foulds supertrees. Our results confirmed the monophyly of the subfamily Plesiotritoninae, while Admetinae and Cancellariinae, as currently conceived, were retrieved as polyphyletic. Based on our findings we propose changes to the systematic arrangement of these subfamilies. At a lower taxonomic rank, our results highlighted the rampant homoplasy of many characters traditionally used to segregate genera, and thus the need of a critical re-evaluation of the contents of many genera (e.g. Nipponaphera, Merica, Sydaphera, Bivetia), the monophyly of which was not recovered.     

基于18S基因序列的姬小蜂分子系统发育

本文基于18S rDNA部分序列,用MP和Baysian方法研究了姬小蜂科的系统发育,对姬小蜂科的单系性及其与其它小蜂科间的关系进行了讨论。姬小蜂亚科、灿姬小蜂亚科和啮姬小蜂亚科形成三个独立的支系,研究结果支持它们各自的单系性,但本结果没有明确姬小蜂科的单系性。研究结果同时还支持瑟姬小蜂族、扁股姬小蜂族和狭面姬小蜂族三个族的地位,但不支持姬小蜂族的地位。姬小蜂科的单系性及其与其它小蜂间的关系还需更多的形态学数据和更多的基因序列来进一步研究[动物学报52 (2) : 288 -301 , 2006]。     

Anteholosticha foissneri n. sp., a marine hypotrich ciliate (Ciliophora: Spirotrichea) from Vietnam: Morphology,morphogenesis, and molecular phylogeny

In a study of marine ciliate diversity, we collected an Anteholosticha monilata-like population from Vietnam. To identify this population, we analyzed its morphology, some morphogenetic stages, and molecular phylogeny. Based on these data, we conclude that the Vietnamese population is new to science. Anteholosticha foissneri n. sp. resembles Anteholosticha monilata-like species considering (1) the number and arrangement of macronuclear nodules and micronuclei; (2) the presence of cortical granules; and (3) the saline habitat. However, the new species can be easily distinguished from these species by the arrangement, color, and shape of the cortical granules. The divisional morphogenesis commences with the de novo proliferation of basal bodies as a single longitudinal patch left of the posteriormost midventral cirral pair. This character state has not been reported before in Anteholosticha (based on check of the available data) and probably reflects a distinct clade within the nuclear small subunit ribosomal RNA gene tree.     

Phylogenetic relationships within the Mysidae (Crustacea, Peracarida, Mysida) based on nuclear 18S ribosomal RNA sequences

Species of the order Mysida (Crustacea, Peracarida) are shrimp-like animals that occur in vast numbers in coastal regions of the world. The order Mysida comprises 1,053 species and 165 genera. The present study covers 25 species of the well-defined Mysidae, the most speciose family within the order Mysida. 18S rRNA sequence analysis confirms that the subfamily Siriellinae is monophyletic. On the other hand the subfamily Gastrosaccinae is paraphyletic and the subfamily Mysinae, represented in this study by the tribes Mysini and Leptomysini, consistently resolves into three independent clades, and hence is clearly not monophyletic. The tribe Mysini is not monophyletic either, and forms two clades of which one appears to be closely related to the Leptomysini. Our results are concordant with a number of morphological differences urging a taxonomic revision of the Mysidae.     

从12S rRNA基因序列探讨中国10种壁虎的系统关系

对肌肉样品采用SDS／蛋白酶K裂解,酚－氯仿抽提和乙醇沉淀提取总DNA,用线粒体12SrDNA通用引物扩增,用银染测序和ABI Prism 310型遗传分析仪测定了Gekko japonicus,G.swinhonis,G.hokouensis,G.gecko,Cyrtopodion elongatus,C.russowi,Teratoscincus roborowskii,Hemidactylus bowringii.,H.frenatus和Gehyra mutilata 10种壁虎的线粒体12SrRNA基因片段的序列,对位排列后的序列长421bp,含201个变异位点,属间核苷酸变异范围为0．228－0．282,属内是0．005－0．263。重建的分子系统树将10种壁虎聚为三支：第1支是大壁虎和截趾虎,第2支由壁虎属其余的3个种构成一个单系;第三支由基余3个属的5个种组成,研究结果表明：截趾虎与壁虎属4物种亲缘关系较近;吐鲁番沙虎和弯脚虎属2物种,晰虎属2物种之间的亲缘关系较近,支持Russell(1976)关于弯脚虎属与晰虎属间进化关系的研究结果而不支持Kluge(1987)将沙虎属另立亚科的系统发生假说;铅山壁虎与无蹼壁虎最先聚为姐妹群,再与多疣壁相聚组成一个单系。     

Molecular phylogeny of the genus Apatrobus (Coleoptera: Carabidae: Patrobinae) in western Japan

We performed a molecular phylogenetic analysis of the ground beetles Apatrobus (Carabidae), endemic to Japan, using the mitochondrial cytochrome c oxidase subunit I (COI) and the nuclear 28S rRNA (28S) genes. We focused on the species divergence in Kyushu, Shikoku and western Honshu and used 15 of 19 species and three populations with undetermined species in the DNA analysis. The gene trees showed that, of the Apatrobus species studied, A. hayachinensis Nakane from northern Honshu was not included in the monophyletic group of the other Apatrobus species and likely to be of a different genus. Divergence time estimation suggested that Apatrobus species excluding A. hayachinensis diverged 5.2 million years ago and the subsequent divergence of species occurred during the Pliocene and Pleistocene. In each of the main islands, Kyushu, Shikoku and Honshu, two or more distinct lineages occurred and all species had restricted distribution areas, suggesting that ancient dispersal and vicariance among the three main islands resulted in the nested biogeographical pattern of species distribution.     

Morphological and molecular description of new species of squat lobster (Crustacea: Decapoda: Galatheidae) from the Solomon and Fiji Islands (South‐West Pacific)

The family Galatheidae is among the most diverse families of anomuran decapod crustaceans, and the South‐West Pacific is a biodiversity hot spot for these squat lobsters. Attempts to clarify the taxonomic and evolutionary relationships of the Galatheidae on the basis of morphological and molecular data have revealed the existence of several cryptic species, differentiated only by subtle morphological characters. Despite these efforts, however, relationships among genera are poorly understood, and the family is in need of a detailed systematic review. In this study, we assess material collected in different surveys conducted in the Solomon Islands, as well as comparative material from the Fiji Islands, by examining both the morphology of the specimens and two mitochondrial markers (cytochrome oxidase subunit I, COI, and 16S rRNA). These two sources of data revealed the existence of eight new species of squat lobster, four of which were ascribed to the genus Munida, two to the genus Paramunida, one to the genus Plesionida, and the last species was ascribed to the genus Agononida. These eight species are described along with phylogenetic relationships at the genus level. Our findings support the taxonomic status of the new species, yet the phylogenetic relationships are not yet fully resolved. Further molecular analysis of a larger data set of species, and more conserved genes, will help clarify the systematics of this group. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 156 , 465–493.