Expanding the taxonomic conundrum: Three new species of groundwater crustacean (Syncarida,Bathynellacea, Parabathynellidae) endemic to the Iberian Peninsula

Two new species of the genus Iberobathynella and one new species of the cosmopolitan genus Hexabathynella are described from the Iberian Peninsula. The three new species were found in the groundwater of caves and the gravelly bank of a river, two species in the north of Spain (Cantabria and Burgos) and one in the south (Sevilla). The two new species of the genus Iberobathynella present a unique combination of characters. These character combinations for the species from Cantabria are: thoracopod 8 female with wrinkled cuticle and two teeth; seven spines on the furca; nine spines on the sympod, three barbed and one plumose seta on the exopod and two barbed setae on the endopod of the uropod; maxilla with 0, 0 and 15 setae on the three segments, respectively; five teeth on the pars incisiva and six teeth on the pars molaris of the mandible and seven segments on the antennule. The combinations of characters for the species from Burgos are: antennule with seven segments; segment 5 of the antennule with one aesthetasc; mandible with four and five teeth on the pars incisiva and pars molaris respectively; maxillule with one seta on segment 1 and 14 setae on segment 3; segment 1 of the endopod of the thoracopod 1 with two setae; uropod with six spines on the sympod, four barbed setae and one plumose seta on the exopod and no setae on the endopod; furca with five spines and the thoracopod 8 female with wrinkled cuticle and two teeth. This last species has an exclusive character for the genus: the absence of setae on the endopod of the uropod. The new species of the genus Hexabathynella has six spines of similar length on the sympod of the uropod (in all other species within the genus the distal spine is longer than the others); the form of the antennal organ in the males is shown to be a new unique character for the genus; the maxilla has three and 13 setae on segments 2 and 3, respectively; the uropod has six spines on the sympod, three barbed setae on the exopod and two smooth setae on the endopod, the endopod is twice as long as the exopod and the shape of the female thoracopod 8 is unique.     

New family and genus Rostrocalanus gen. nov. (Crustacea: Calanoida: Rostrocalanidae fam. nov.) from deep Atlantic waters

Two new species of a new genus and family Rostrocalanidae of benthopelagic clausocalanoid copepods are described from female specimens collected from abyssal depths close to the sea bed in the tropical Atlantic. Rostrocalanus gen. nov. shares the presence of sensory setae on maxilla with other bradfordian families of Clausocalanoidea, but does not fit the diagnosis of any of these families. A family Rostrocalanidae is established for this new genus and is defined by the following derived characters: four‐segmented exopod of mandible supplied with four setae; distal basal endite of maxillule fused to endopod and bearing five setae in total; endopod of maxilla furnished with six worm‐like sensory setae; arrangement of setal numbers on praecoxal endites of maxilliped syncoxa as 0, 1, 2. The establishment of a new clausocalanoidean family sheds new light on the morphological diversity of bradfordian benthopelagic copepods and adds to the biodiversity of the deep‐water calanoid fauna.     

The complete larval development of Sadayoshia edwardsii (37) (Decapoda: Anomura: Galatheidae) described from laboratory‐reared material

The complete larval development of Sadayoshia edwardsii (Miers, ) is described and illustrated from laboratory‐reared material. The development comprises four zoeal and one megalopal stages. Diagnostic zoeal characters of Sadayoshia are provided and these are compared with other galatheid genera for which the larval morphology is known. Zoeas of S. edwardsii are readily distinguished from those of other galatheid species by the setation of the maxillular endopod together with the basis and endopod of the first maxilliped. The megalop of S. edwardsii has a flattened, triangular‐shaped rostrum, which differs remarkably from that of the adult. Although the rostral shape resembles that of Galathea megalops, the armature of the lateral margins is different between megalops of the two genera. The present larval study suggests that Sadayoshia is more closely allied to Galathea than to Munida.     

The larval development of the spider crab Rochinia gracilipes (Crustacea: Majoidea: Epialtidae: Pisinae) reared in the laboratory

The larval development of the spider crab Rochinia gracilipes Milne-Edwards, 1875 (Crustacea: Decapoda: Brachyura: Majoidea: Epialtidae: Pisinae) is described and illustrated from laboratory-reared larvae. Development consisted of two zoeal stages and one megalopa, following the typical pattern in Majoidea. Zoea I of R. gracilipes, R. debilis and R. carpenteri differed in lengths of the rostral spine of the carapace, in the number of setae and aesthetascs of several head appendages (exopods of antennules, endopods of maxillules, and endopods and scaphognathites of maxillae) and in the length of posterolateral processes of abdominal somites; lateral carapace spines were present only in R. carpenteri and pleopod buds only in R. debilis. Megalopae of Rochinia gracilipes and R. carpenteri differed in several notable characters: a dorsal spine and long rostrum of the carapace, as well as spines in coxa and ischium of pereiopods, appeared only in R. carpenteri, and podobranchiae of the 3rd maxilliped appeared only in R. gracilipes; they also differed in setation of abdomen and pleopods. The comparison of the available information on Pisinae larval development suggested that larval morphology would not help to accurately understand the phylogenetic relationships of this subfamily of spider crabs.     

Complete larval development of the rare porcellanid crab,Novorostrum decorocrus Osawa, 1998 (Crustacea: Decapoda: Anomura: Porcellanidae), reared under laboratory conditions

The complete larval development of Novorostrum decorocrus Osawa, , is described and illustrated on the basis of laboratory‐reared material. Two zoeal stages and one megalop stage were recorded. Zoeas of N. decorocrus closely resemble those of N. indicum in the appendage characters, including the endopod of the maxillule with only a single stout seta on the distal margin. This character is unique to Novorostrum zoeas. However, N. decorocrus is distinguished from N. indicum by the setation on the endopod of the maxilla and the basis of the second maxilliped in both zoeal stages. The megalops of N. decorocrus are characterized by having a strongly elongate carapace, and differs considerably from the adults in the structure of the carapace, rostrum and third thoracic sternite, and in the armature of the pereiopods. The larval duration of N. decorocrus suggests that this rare porcellanid is more widely distributed than currently known.     

New species of Brodskius,Rythabis, and Omorius (Crustacea: Calanoida) from deep Antarctic waters

Three new species of rare benthopelagic clausocalanoidean genera with sensory setae on the maxilla are described from female specimens collected during the German Antarctic expeditions ANDEEP I–III in 2002 and 2005, mainly from abyssal depths close to the sea bed. Brodskius abyssalis sp. nov. differs from congeners by the lack of rostral filaments, two setae on the second segment of antenna exopod, thread‐like tips of maxillary worm‐like sensory setae, and the length of spines of P5 exopod. Rythabis assymmetrica sp. nov. is distinguished from other species in the genus by asymmetrical posterior corners of the prosome, the shape of spermathecae, and setal numbers on the maxillulary distal basal endite plus endopod. Omorius curvispinus sp. nov. is characterized by strongly curved setae of the maxillipedal syncoxa, a comparatively long seta on the basis of antenna, a slightly swollen genital double‐somite, and the shape of spermathecae. The genera Brodskius, Omorius, and Rythabis are recorded for the first time from the southern hemisphere.     

Zoeal development of Ethusa microphthalma smith, 1881 (Brachyura,Dorippidae) reared in the laboratory,with a comparison of other dorippid zoeae

The complete zoeal development of a dorippid crab in the subfamily Ethusinae is described for the first time from a known parental female. The ovigerous Ethusa microphthalma was collected in the northern Gulf of Mexico off Louisiana. Larvae passed through four zoeal stages, and the megalopa was reached in 59 days at 20°C and 35 ppt salinity. The larvae differ from those of the few other dorippids for which a zoea is known. Salient distinguishing features include long lateral carapace spines, the presence of six setae on the endopod of the maxillule and maxilla, and a spinose antennal exopod lacking projecting mid-length spines or setae. Zoeal characters are compared to those known for the allied subfamily Dorippinae, and all references to zoeae of the Dorippidae are tabulated.     

Stephonyx californiensis sp. nov. (Amphipoda: Lysianassoidea: Uristidae), a new bathyal scavenger species from the Central Gulf of California,Mexico, and comments on the bathymetric and geographic distribution of the Stephonyx species group

A new species of scavenger amphipod of the genus Stephonyx is described and illustrated. The specimen was caught at 1150 m depth with a modified rectangular lobster trap positioned on the sea bottom in the central Gulf of California, Mexico. The new species is characterised by the absence of eyes; the lateral cephalic lobes medially developed and acute; antennae subequal in length; gnathopod 1 chelate, dactylus simple with three distal stout setae, inner margin sinuous with minute setae; gnathopod 2 subchelate, carpus with ventral margin crenulate, propodus subovate, palm deeply excavate, and dactylus slightly shorter than palm; maxilliped inner plate laceolate, with seven marginal nodular robust setae, distally; telson, each lobe with two dorsal robust setae, distal margin truncated, with one penicillate and two simple setae, in addition to two short spines. Stephonyx californiensis sp. nov. is morphologically similar to S. arabiensis, S talismani, S. laqueus and S. perexcavatus. The new species increases the number of Stephonyx species around the world to 14, with one species inhabiting from the continental shelf to abyssal depths (to 3000 m), 11 species occurring in bathyal depths (201–2000 m), and two other species restricted to abyssal depths (2001–4000 m).

www.zoobank.org/urn:lsid:zoobank.org:pub:346C3B15-E56A-4E17-9C5F-C9FDBB2AED92     

Two new deep-sea species of Argestidae and Ameiridae (Copepoda: Harpacticoida) from the Eastern Mexican Pacific and Gulf of California,with proposal of a new genus of the family Argestidae

ABSTRACT

A handful of benthic harpacticoid species are known from the Gulf of California. Here I describe Argestes analongises sp. n. (Argestidae), and Argestigens celibis sp. n. (Ameiridae) from the deep sea of the Tropical Eastern Pacific and Gulf of California. Argestes analongises sp. n. fits in the subfamily Argestinae (Argestidae) and was attributed to the genus Argestes by the presence of small spinules covering the body surface of, at least, the urosome, and by the presence of an extremely elongated distal seta on the sixth segment of the female antennule. This new species seems to be allied to A. angolaensis by the situation of all the caudal setae, and by the ventral position of caudal seta III. They differ in the relative length of the female caudal rami, size, shape and relative position of the sensilla-bearing tubercles associated to the anal somite, armature of the mandibular basis, shape of the exopodal and endopodal segments of swimming legs, and relative length of the setae on the female P5 endopodal lobe and position of the innermost seta of the exopod of the female fifth leg. Argestigens celibis sp. n. was attributed to the family Ameiridae based on the non-argestid maxilla, on the presence of a more or less well-developed endopodal lobe of the male fifth leg and three inner setae on the third endopodal segment of the third leg, and on the presence of the typically modified ameirid-like inner spine on the basis of the male first leg. The new species was attributed to Argestigens based on the non-prehensile endopod of first leg and presence of long inner spinules on the basis of second to fourth legs. Additionally, a new genus, Georgus gen. n., is proposed for Bodinia peterrumi, and some comments are given on the monophyly of that genus.

www.zoobank.org/urn:lsid:zoobank.org:pub:4BD580B0-E856-4FBC-ABA6-B031A9B6E1F9     

First record of Syncarida from Queensland,Australia, with description of two new species of Notobathynella Schminke, 1973 (Crustacea,Bathynellacea, Parabathynellidae)

Two new species of the parabathynellid genus Notobathynella Schminke, 1973 Schminke, HK. 1973. Evolution, System und Verbreitungsgeschichte der Familie Parabathynellidae (Bathynellacea, Malacostraca)Akad Wiss Lit Mainz, Math-Naturwiss Klasse, Mikrofauna Meeresbodens, 24: 1–192.  [Google Scholar] are described from Australia: N. octocamura sp. nov. and N. pentatrichion sp. nov. Notobathynella octocamura sp. nov. has eight claws on the distal endite of the maxillule, a character that is unique in the Parabathynellidae. It is also the first species of the genus with the following characters: five setae on the terminal segment of antenna, 26–28 teeth on labrum, 31 setae on maxilla, a three-segmented exopod on thoracopod I, five-segmented exopods on thoracopods IV and V, three setae and two claws on the fourth endopodal segment of thoracopods I to IV, and six setae on the uropodal exopod. This species also has a unique setal formula for some thoracopods. Notobathynella pentatrichion sp. nov. is unique in the genus with five setae on the uropodal exopod and, like N. octocamura sp. nov., has a one- or two-segmented exopod on thoracopod I, a four- or five-segmented exopod of thoracopod V, and three setae and two claws in the four segments of the endopod of thoracopods II to IV. The two new species extend the distribution of Bathynellacea in Australia and are the first species to be described from Queensland.     

The first record of Syncarida in Montana,USA: a new genus and species of Parabathynellidae (Crustacea,Bathynellacea) in North America

Montanabathynella salish gen. nov. sp. nov., of the family Parabathynellidae, from Montana, USA, is described. The new species displays several exclusive characters: distal endite of the maxillule with nine claws and a very large and distinctive male thoracopod 8 with four lobes in the basal penial region and a long recurved exopod without setation. It also presents a unique combination of characters: antennule seven‐segmented; antenna six‐segmented; labrum with 18 teeth; exopod of thoracopods three‐ to six‐segmented, endopod with one dorsal seta on the first and second segments and epipod only present on thoracopods 4 to 7; pleopods absent; endopod of thoracopod 8 male with two setae and exopod without setae; female thoracopod 8 having two segments, first segment with two groups of denticles and the second one with three long barbed setae; 15 spines on sympod, four spines and spinous process on endopod and 12 setae on exopod of uropod.     

Disentangling an Asian puzzle: Two new bathynellid (Crustacea,Syncarida, Parabathynellidae) genera from Vietnam

In this paper the 17 asiatic species of the family Parabathynellidae are reviewed from a taxonomic point of view using bibliographic data. Two new genera and two new species are described from caves in Vietnam. Paraeobathynella n. g. presents a unique combination of characters (antennule: seven segments; antenna: six segments; mandible: pars incisiva with five teeth and pars molaris with 10 teeth; maxillule: distal endite with seven claws; exopod of the thoracopods with three or more segments and epipods present in thoracopods 3–7; pleopods absent; endopod of the Th 8 male with two setae; seven spines on the sympod and two spines on the endopod of the uropod and the small minimum size of the adult body) and exclusive characters like the Th 8 female having two small spines and one long seta and the general size and aspect of the Th 8 male and its lobes. Sketinella n. g. presents a unique combination of characters (antennule: eight segments; antenna; six segments; mandible: pars incisiva with six teeth and pars molaris with eight teeth: maxillule: distal endite with seven claws; exopod of the thoracopods with three or more segments and epipods present in Th 3–7; endopod of the thoracopod 8 male with two setae; 12 spines on the sympod and two spines on the endopod and seven setae on the exopod of the uropod) and characters exclusive to the asiatic species are: a pair of pleopods reduced to a single seta; a very distinctive basipod and outer lobe of the Th 8 male and an exopod of the Th 8 male with a small tooth or protuberance. This is the first time that the Parabathynellidae has been found in Vietnam, this find extends the range of distribution of this family in Asia.     

Two new species of Siphonostomatoida (Copepoda) found on cnidarians in Tokara Islands,Southern Japan

ABSTRACT

Two new species of siphonostomatoid copepods are described based on specimens collected off Tokara Islands located in the northern part of the Ryukyu Islands, Southern Japan. Cholomyzon multisetum sp. nov. (Coralliomyzontidae) found from the orange cup coral Tubastraea coccinea Lesson, 1829 (Hexacorallia: Scleractinia: Dendrophylliidae) has the following characters: armature formula of the antennule of the female; the outer lobe of the maxillule; and numbers of elements on the legs 1 to 3. Another species, Entomopsyllus takara sp. nov. (Entomolepididae), was found from both the Indo-Pacific blue coral Heliopora coerulea (Pallas, 1766) (Octocorallia: Helioporacea: Helioporidae) and the race coral Distichopora violacea (Pallas, 1766) (Hydrozoa: Anthoathecata: Stylasteridae). This new species of the male specimen is characterized by the antennule with shortest sixth segment, the endopod of leg 2 bearing two inner setae on the second segment and five setae on the third segment, the third exopodal and endopodal segments of leg 3 bearing three spines and three setae, respectively, and the third exopodal segment of leg 4 bearing four setae. These two species represented the first records of the families Coralliomyzontidae and Entomolepididae from Japanese waters.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:7C8DED0A-9CEB-405D-9BBF-FAF2043B0858     

The first record of the genus Vejdovskybathynella Serban and Leclerc, 1984 (Syncarida,Bathynellacea, Bathynellidae) in the Iberian Peninsula: three new species

Three new species of the genus Vejdovskybathynella are described from caves in northern Spain. It is the first time that this genus has been documented in the Iberian Peninsula. Vejdovskybathynella edelweiss n. sp. has several unique features: the setal formula of the antenna (0/2+exp/2+0/1+0/0+0/2+2/4); the form of the segments and claws of the mandibular palp of the mandible of the male; exopod of the female thoracopod VIII similar in size to the endopod (exopod is always longer than the endopod); small frontal projection of the basipod of the male thoracopod VIII, large or very large is common; the form and size of the lobes of the male thoracopod VIII is unique; the second spine of the furcal rami 2.5 times longer than the first spine. Vejdovskybathynella caroloi n. sp. has a unique male thoracopod VIII with a spur in the exopod that is a feature unknown in the genus, and additionally, this species has the smallest endopod of the thoracopod VIII male of the entire genus; the presence of three aesthetascs in segments VI and VII of the antennule had not been observed in this genus until now; the form of the segments of the mandibular palp of the mandible of the male are unique; the distal spine of the sympod of the uropod is larger than in other species, whereas in the rest of the species of the genus they are equal in size. Vejdovskybathynella pascalis n. sp. is the smallest species of the genus and has two and three aesthetascs in segments VI and VII of the antennule, respectively; it is the only species of the genus that has one seta on segment I and two setae on segment IV of the antenna; it has a unique male thoracopod VIII with a small spur on the frontal projection of the basipod and with the endopod larger than all other species in spite of its small size; the basal spine of the sympod of the uropod is smaller than the other three.     

New records of Bathynellacea (Syncarida,Bathynellidae) in North America: three new species of the genus Pacificabathynella from Montana,USA

Three new species of the genus Pacificabathynella Schminke and Noodt, 1988 Schminke, H K and Noodt, W. 1988. Groundwater Crustacea of the order Bathynellacea (Malacostraca) from North America. J Crustacean Biol., 8(2): 290–299.  [Google Scholar] are described from groundwater aquifers in glaciated North America (Montana, USA). This is the first time that this genus, known previously only from the state of California, has been documented in Montana. Pacificabathynella and Paradoxibathynella Serban, 2000 Serban, E. 2000. Uenobathynella n.g., Parauenobathynella n.g., Morimotobathynella n.g., Nihobathynella n.g. et Paradoxibathynella n.g., Bathynellinae du Japón (Bathynellidae, Bathynellacea, Podophallocarida). Travaux Inst Spéol “Émile Racovitza”, 36: 3–61.  [Google Scholar] are the only genera that show sexual dimorphism in thoracopod VI. Pacificabathynella kalispellensis sp. nov. has several unique features: the setal formula of the antenna (0/2+exop/3/12/6/8/5); the setal formula of the maxilla (7/4/7/6); the presence of an epipod on thoracopod II; tufts of setulae and abundant setae on the basipod and endopod of thoracopods I to V; the epipod of thoracopod VIII female three times longer than the basipod; three smooth setae on the exopod of the female thoracopod VIII; eight spines on the endopod of the uropod and the endopod longer than the sympod, whereas the opposite is typical. Pacificabathynella stanfordi sp. nov. has several unique features: only five setae on the exopod of thoracopods II to VII, while six setae are common in the genus; only six setae on the second segment of the first pleopod; five spines on the endopod and seven setae on the exopod of the uropod. Pacificabathynella ruthae sp. nov. is the largest species and has several unique features: antennule equal in size to the antenna, whereas in the rest of the species of the genus the antenna is larger; the projection of the inner lobe of the male thoracopod VIII is bidentate and there are six spines on the endopod and nine setae on the exopod of the uropod. The three new species have slight differences in the pars molaris of the mandible and in thoracopod VIII of males, and there are other minor differences between the females and the species Pacificabathynella sequoiae. The new taxa, together with the new genus Montanabathynella described separately, represent a 30% increase in North American taxa. Considering the glaciated landscape and the fragmented nature of alluvial aquifer habitat, we believe that there is a profound lack of critical knowledge of the biogeography and biodiversity of syncarids in North America.     

Three new species of the deep-sea genus Neotanais Beddard (Crustacea: Peracarida)

Three new species of the deep-water family Neotanaididae Lang are described. Neotanais minimus n. sp. and N. curvimanus n. sp. were collected from the Gulf of Mexico and are the first species to be described from this region. Neotanais minimus cannot be grouped with other Neotanais species, since it displays characters from all groupings. Neotanais curvimanus has strong affinities to the ‘americanus’ group but can be separated by the short pereonite 6 and by the presence of many setulose setae lateral on the pleonites. Male N. curvimanus can easily be separated from all other species of the genus by the cheliped fixed finger being only half as long as the dactylus and the dactylus being incurved from fixed finger at an angle of about 40°. Neotanais noelietaiti n. sp. was found off south-east Australia and is the first Neotanais species to be described from Australian waters. It also has strong affinities to the ‘americanus’ group but can be distinguished by the complete lack of a midventral keel and by the uropodal exopod being as long as the endopod article 1.     

An overview of Hexabathynella (Crustacea,Syncarida, Parabathynellidae) with the description of a new species

A new species of the cosmopolitan genus Hexabathynella is described from Spain. This new species has four setae on the expopod of the uropod, the rest of the species in the genus have between one and three. The endopod of the uropod has two smooth setae of similar length and one plumose seta, these characters only appear in the new species within the genus. The antennal organ in the males is shown to be a new unique character for the genus. It is the third species of this genus that has been found in Spain. To date the genus consists of 18 species in the world. A key for identification of the 18 species of Hexabathynella is provided. It is the only cosmopolitan genus of Bathynellacea and it is distributed in Europe (nine species), Africa (one species), South America (two species), North America (three species) and Australia and New Zealand (three species).     

A new genus for Acanthomysis schrencki (Czerniavsky, 1882) (Crustacea: Mysida: Mysidae) with the first description of the male

A new genus, Boreoacanthomysis, is established for the reception of Acanthomysis schrencki. The new genus is characterized by the fourth male pleopod armed with a pair of long plumose setae at the distal end of the proximal segment of the exopod, and by the uropodal endopod armed with about 30 spines near the statocyst. The male of this species is described for the first time.