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This paper reports on the genus Cobbionema Filipjev, 1922 in Sweden with the description of four species and a revision of the genus. Cobbionema acrocerca Filipjev, 1922 is relatively small in size, with a tail that has a conical proximal and a digitate distal section. Cobbionema cylindrolaimoides Schuurmans Stekhoven, 1950 is similar to C. acrocerca in most characters except having a larger body size and heavily cuticularized mandibles. Cobbionema brevispicula sp. nov. is characterised by short spicules and a conoid tail. Cobbionema acuminata sp. nov. is characterised by a long two-part spicule, a conical tail and three (one mid dorsal and two ventrosublateral) sharply pointed tines in the anterior chamber of the stoma that are located more anterior than in all the other species. We also present a molecular phylogeny of the family based on the nearly full-length 18S and the D2-D3 expansion segment of the 28S rRNA genes. Maximum Likelihood and Bayesian trees inferred from both genes strongly support a clade that included Cobbionema, Demonema Cobb, 1894 and Halichoanolaimus de Man, 1888 and another clade with Gammanema Cobb, 1920 and Latronema Wieser, 1954 nested together. None of the trees supported the monophyly of the subfamilies Choniolaiminae and Selachinematinae.
We compared Chatham Island endemic species Xanthocnemis tuanuii to its congenerics from the New Zealand South Island: X. zealandica (newly collected specimens)and X. sinclairi (type specimens plus newly collected material). Two independent tests were performed –geometric morphometrics and molecular. Both analyses were consistent in supporting the status of X. tuanuiias a good species. Species differed statistically in the following morphological traits: head (dorsal view), male appendages (dorsal, lateral, posterior and ventral views), thorax (dorsal view), and penis (dorsal and lateral view). In addition to the original diagnostic features (mainly shape of the male superior appendages), a new morphological character is suggested here which reliably distinguishes the species based on the shape of the inferior appendages. There was no statistical support for the species status of X. sinclairi. The only feature re-ported as diagnostic (lower lobe of male superior appendages) was found to be variable and insufficient to warrant the previously proposed taxonomic rank for X. sinclairi. Molecular analysis of specimens showing identical appendages to the X. sinclairi holotype grouped them with X. zealandica specimens. Therefore X. sinclairi is synonymised with X. zealandica.
During mycological surveys of different areas of Punjab, Pakistan, we collected a new species from the genus Candolleomyces. This is the first report of any species of this genus from Pakistan. Candolleomyces asiaticus M.Asif, A.Izhar, Niazi & Khalid sp. nov. is characterized by ellipsoid to oblong-ellipsoid (8.2 × 5 µm) basidiospores with indistinct germ pores, lageniform to utriform cheilocystidia without adhering deposits at the apices, absence of pleuro-, pileo- and caulocystidia, pileipellis with spherical, subglobose to columnar cells, and presence of clamp connections. The morpho-anatomical and molecular phylogenetic analysis of nrITS revealed its distinct phylogenetic position, further supporting the recognition of a new species.
A new monospecific genus belonging to the family Linyphiidae Blackwell, 1859, Nihonella gen. nov., is described using an integrative taxonomic approach based on the species N. chika gen. et sp. nov. The new genus is endemic to Western Honshu, Japan, and it shows distinctive genitalic and somatic characters of other genera of the subfamily Erigoninae Emerton, 1882. Nihonella gen. nov. is found only in the twilight and transition zones of caves in Okayama and Nara Prefectures. The phylogenetic position of Nihonella gen. nov. within the subfamily Erigoninae, and its relationship as a sister clade of the species of the group of Savignia Blackwell, 1833 (sensu Millidge 1977), is discussed on the basis of both, morphological and molecular evidence.
Remipedia is a stygobitic group commonly associated with coastal anchialine caves. This class consists of 12 genera, ten of which are found within the Lucayan Archipelago. Herein, we describe a new species within the genus Godzillius from Conch Sound Blue Hole, North Andros Island, Bahamas. Godzillius louriei sp. nov. is the third known remipede observed from a subseafloor marine cave, and the first from the Godzilliidae. Remipedes dwell within notoriously difficult to access cave habitats and thus integrative and comprehensive systematic studies at family or genus level are often absent in the literature. In this study, all species of Godzillius are compared using morphological and molecular approaches. Specifically, the feeding appendages of G. louriei sp. nov., G. fuchsi Gonzalez, Singpiel & Schlagner, 2013 and G. robustus Schram, Yager & Emerson, 1986 were examined using scanning electron microscopy (SEM). Species of Godzillius are identified based on the spines of maxilla 1 segment 4 and by the denticles on the lacinia mobilis of the left mandible. A molecular phylogeny using the mitochondrial 16S rRNA and nuclear histone 3 genes recovered G. louriei sp. nov. within the Godzillius clade and 16S genetic distances revealed a 13–15% difference between species of Godzillius.
The subfamily Sepiolinae (Mollusca: Cephalopoda: Sepiolidae), currently containing the genera Sepiola Leach, 1817, Euprymna Steenstrup, 1887, Inioteuthis Verrill, 1881, Rondeletiola Naef, 1921 and Sepietta Naef, 1912, is characterized by the hectocotylization of the left dorsal arm, i.e., its transformation into a copulatory organ thanks to modifications of sucker/pedicel elements. The hectocotylus morphology varies to a great extent across genera and species. In particular, one to several pedicels in its proximal third lose their sucker and become highly and diversely modified in shape to constitute a copulatory apparatus. An evolutionary gradient was observed in the copulatory apparatus morphology, from the simple modification into a papilla of just one pedicel from the third element of the ventral sucker row (some nominal species of Euprymna) to a quite complex structure involving several variously modified pedicels from both the ventral and dorsal sucker rows (Inioteuthis). In some species, elements in the distal portion of the hectocotylus may also be highly modified, such as the columnar suckers in Euprymna. The hectocotylian diversity allows to distinguish nine groups of species that do not match the current generic subdivision of Sepiolinae. Additional morphological characters (number of sucker rows on arms, female bursa copulatrix, occurrence and shape of visceral light organs, etc.) corroborate the subdivision of Sepiolinae into nine subtaxa, i.e., genera. Accordingly, a cladogram is drawn to describe the possible phylogenetic relationships among the nine clades. To comply with these results, all current genera are redefined and four new genera are described, namely Adinaefiola gen. nov., Boletzkyola gen. nov., Eumandya gen. nov. and Lusepiola gen. nov.
Background: The current taxonomy of the African giraffe (Giraffa camelopardalis) is primarily based on pelage pattern and geographic distribution, and nine subspecies are currently recognized. Although genetic studies have been conducted, their resolution is low, mainly due to limited sampling. Detailed knowledge about the genetic variation and phylogeography of the South African giraffe (G. c. giraffa) and the Angolan giraffe (G. c. angolensis) is lacking. We investigate genetic variation among giraffe matrilines by increased sampling, with a focus on giraffe key areas in southern Africa.
Results: The 1,562 nucleotides long mitochondrial DNA dataset (cytochrome b and partial control region) comprises 138 parsimony informative sites among 161 giraffe individuals from eight populations. We additionally included two okapis as an outgroup. The analyses of the maternally inherited sequences reveal a deep divergence between northern and southern giraffe populations in Africa, and a general pattern of distinct matrilineal clades corresponding to their geographic distribution. Divergence time estimates among giraffe populations place the deepest splits at several hundred thousand years ago.
Conclusions: Our increased sampling in southern Africa suggests that the distribution ranges of the Angolan and South African giraffe need to be redefined. Knowledge about the phylogeography and genetic variation of these two maternal lineages is crucial for the development of appropriate management strategies.
Cteniogaster, a new genus of small ground spiders is described from Kenya and Tanzania. It encompasses seven new species, three of which are known from both sexes: C. toxarchus sp. nov., the type species, C. conviva sp. nov. and C. hexomma sp. nov. Three species are known from females only: C. lampropus sp. nov., C. sangarawe sp. nov. and C. taxorchis sp. nov. and one only from males: C. nana sp. nov. The new genus can be recognised by the presence of a posterior ventral abdominal f eld of strong setae and anterior lateral spinnerets with enlarged piriform gland spigots in males. A cladistic analysis attributes the genus to Liocranidae, Cybaeodinae. The results of the analysis performed do not produce an unequivocal autapomorphy for Liocranidae, but provide a combination of non-homoplasious character changes that offers significant potential for recognising genera as Liocranidae. Moreover, robust apomorphies are determined within Liocranidae for the subfamilies Liocraninae and Cybaeodinae. Based on these fi ndings Toxoniella Warui & Jocqué, 2002 is transferred from Gallieniellidae to Liocranidae, Cybaeodinae. Jacaena Thorell, 1897, Plynnon Deeleman-Reinhold, 2001 and Teutamus Thorell, 1890 are transferred to Corinnidae, Phrurolithinae and Montebello Hogg, 1914 to Gnaphosidae. Itatsina Kishida, 1930 is synonymised with Prochora Simon, 1886.
Olpidiopsis is a genus of obligate holocarpic endobiotic oomycetes. Most of the species classified in the genus are known only from their morphology and life cycle, and a few have been examined for their ultrastructure or molecular phylogeny. However, the taxonomic placement of all sequenced species is provisional, as no sequence data are available for the type species, O. saprolegniae, to consolidate the taxonomy of species currently placed in the genus. Thus, efforts were undertaken to isolate O. saprolegniae from its type host, Saprolegnia parasitica and to infer its phylogenetic placement based on 18S rDNA sequences. As most species of Olpidiopsis for which sequence data are available are from rhodophyte hosts, we have also isolated the type species of the rhodophyte-parasitic genus Pontisma, P. lagenidioides and obtained partial 18S rDNA sequences. Phylogenetic reconstructions in the current study revealed that O. saprolegniae from Saprolegnia parasitica forms a monophyletic group with a morphologically similar isolate from S. ferax, and a morphologically and phylogenetically more divergent species from S. terrestris. However, they were widely separated from a monophyletic, yet unsupported clade containing P. lagenidioides and red algal parasites previously classified in Olpidiopsis. Consequently, all holocarpic parasites in red algae should be considered to be members of the genus Pontisma as previously suggested by some researchers. In addition, a new species of Olpidiopsis, O. parthenogenetica is introduced to accommodate the pathogen of S. terrestris.
Obligate endoparasitic oomycetes are known to ubiquitously occur in marine and freshwater diatoms, but their diversity is still largely unexplored. Many of these parasitoids are members of the early-diverging oomycete lineages (Miracula, Diatomophthora), others are within the Leptomitales of the Saprolegniomycetes (Ectrogella, Lagenisma) and some have been described in the Peronosporomycetes (Aphanomycopsis, Lagenidium). Even though some species have been recently described and two new genera were introduced (Miracula and Diatomophthora), the phylogeny and taxonomy of most of these organisms remain unresolved. This is contrasted by the high number of sequences from unclassified species, as recently revealed from environmental sequencing, suggesting the presence of several undiscovered species. In this study, a new species of Miracula is reported from a marine centric diatom (Minidiscus sp.) isolated from Skagaströnd harbor in Northwest Iceland. The morphology and life cycle traits of this novel oomycete parasite are described herein, and its taxonomic placement within the genus Miracula is confirmed by molecular phylogeny. As it cannot be assigned to any previously described species, it is introduced as Miracula islandica in this study. The genus Miracula thus contains three described holocarpic species (M. helgolandica, M. islandica, M. moenusica) to which likely additional species will need to be added in the future, considering the presence of several lineages known only from environmental sequencing that clustered within the Miracula clade.