Spiniform Setae Research Articles

Oahutanais makalii , a new genus and species of colletteid tanaidacean (Crustacea, Peracarida) from shelf-waters off Hawaii, with a taxonomic key

A new colletteid tanaidacean, Oahutanais makalii gen. et sp. n., is described from Hawaiian coastal waters at depths ranging from 19 to 102 m. The new taxon is tentatively designated as a new genus, although it displays many features in common with the genus Leptognathiella. The new species is distinguished from the morphologically similar tanaidomorphans by having (1) a small body, less than 1.0 mm (reproductively active specimens), (2) a maxillule with two bifid spiniform setae; (3) a maxilliped palp article-2 with geniculate, finely pectinate spiniform seta on sub-distal inner margin, (4) a cheliped attachment ventrally via sclerite not connected to the carapace, and (5) the pereopods 1 to 6 with ischial seta shorter than the merus. A key to the five extant genera of Colletteidae in the North Pacific Ocean is presented herein.

Two new species of Leptochelia Dana, 1849 (Peracarida, Tanaidacea) from Cuba

To date, only one species ofLeptocheliaDana, 1849 has been described from the Cuban archipelago,L. tenuiculaMakkaveeva, 1968, and two others have been recorded,L. forresti(Stebbing, 1896) andL. savignyi(Krøyer, 1842). From new collections in the area, herein two new species are described,L. ortizin. sp. andL. pinarensisn. sp. Males ofL. ortiziare distinguished by the possession of two small, unequal medial processes on the cutting edge of the cheliped fixed finger, and six spiniform setae on the inner margin of the dactylus. Females bear an inner row of fine setules on the lacinia mobilis of the left mandible. Likewise, females ofL. pinarensisare recognized by having two plumose setae on the inner margin of the fourth article of the maxilliped. The addition of these two species increases the number of species of the genus in Cuba to five.

First species of Leptochelia Dana, 1849 (Crustacea: Tanaidacea) from the Eastern Pacific, with an annotated checklist and identification keys for the genus.

Forty three species of leptocheliids are known worldwide. In the American region only eight species have been described from the Western Atlantic, while for the Eastern Pacific none have been described, suggesting that the diversity of this family has been severely underestimated in this region. Here we describe the first species of Leptochelia from the Eastern Pacific, Leptochelia mexicana n. sp., which is characterized by the males having a spiniform seta on the second segment of uropodal endopod, a novel feature for the genus. In addition, the first annotated checklist and a taxonomic key with illustrations for Leptochelia species are included. The list includes the type locality, type depository, distribution, habitat and, in some cases, remarks.

Two new species of the deep-sea genus Neotanais Beddard, 1886 (Tanaidacea: Neotanaididae) from the eastern central Pacific

We describe two new species of deep-water neotanaids collected from the Korea Deep Ocean Study (KODOS) Area in the eastern central Pacific. Neotanais pacificus is distinguished from other species of Neotanais by the following morphological combination: in the female: 1) pereiomere 5 is the longest of the pereiomeres, 2) distal claw of the cheliped fixed finger bulges outward, and the cutting edge descends steeply, 3) the uropod exopod is much longer than first endopodal article, 4) the setal row of the left mandible has bi-serrated setae and plumose seta, 5) the maxilliped endite bears three bipinnate spiniform setae on the inner posterior margin and medially expanded plumose seta on the distal margin, and 6) the propodi of pereipods 1 to 3 bear thick bi-pinnate spiniform setae. The female of N. capillus distinctly differs from other species of Neotanais by the following morphological combination: 1) pereiomeres 4 and 5 are longer than wide, 2) the pleomeres are without midventral spurs, 3) the pleotelson bears fine setules along the distal margin, 4) the maxilliped endite has a very long plumose seta on the distal outer corner and two bipinnate spiniform setae on inner posterior margin, 5) the propodi of pereiopods 1 to 6 have thick bipinnate spiniform setae, and 6) the uropod is shorter than the pleon. In this study, distinct morphological characters differentiating the N. pacificus and N. capillus from other species of Neotanais are given on the basis of detailed descriptions.

A new species of the genus Diplocentrus Peters, 1861 (Scorpiones, Diplocentridae) from Oaxaca, Mexico.

A new species of the genus Diplocentrus Peters, 1861 is described, based on several specimens collected in the Mexican state of Oaxaca. It is characterized by a high telotarsal spiniform setae count (4-5/5:5/6:6/6:6/6-7), and the pectinal tooth counts of 12–15, mode = 13 (male) or 11–13, mode = 12 (female). With the description of this species, the diversity of the genus is increased to 51 species in Mexico.

Description of the larva ofArgia jujuyaRis (Coenagrionidae) with a key to species from the Argentinean Yungas cloud forest

The previously unknown larva of Argia jujuya Ris, 1913 is described, diagnosed and illustrated. Among other characters, the following combination is important to distinguish it from other species in the genus: antennae with six concolorous segments, ligula projected only slightly, row of small premental setae present, abdominal sternum 8 almost entirely covered with spiniform setae, gonapophyses with pointed apices slightly diverging distally, cercus triangular, caudal lamellae subequal in length and triquetral along entire length, with fringe of stout setae along entire dorsal and ventral margins. Larvae were collected in very small and thickly vegetated streams, with low water current. A key for the three species known as larvae in NW Argentina is presented.

Description of three species of Halmyrapseudes (Crustacea: Tanaidacea: Parapseudidae), with a discussion of biogeography.

We describe Halmyrapseudes gutui sp. nov. from a mangrove area on Lidee Island, southern Thailand. This species closely resembles H. cooperi, H. killaiyensis, and H. thaumastocheles, but differs in having the lacinia mobilis with three teeth, and the pereopod 1 carpus with 0,1 or 1,1 ventral simple setae proximal to each spiniform seta. We redescribed and synonymized two species of questionable affiliation, Apseudes cooperi and A. digitalis, placing them in Halmyrapseudes, and partly redescribed Halmyrapseudes killaiyensis. Halmyrapseudes and Pseudohalmyrapseudes have disjunct distributions. Halmyrapseudes is similar in distribution to two freshwater fish taxa whose distributions are considered to reflect the breakup of Gondwana and subsequent continental drift. Pseudohalmyrapseudes occurs around Australia, and its distribution seems to be separated from that of Halmyrapseudes by Wallace's Line or Huxley's Line, which are distributional barriers for both terrestrial organisms and an amphidromous shrimp. The adjacent distributions and morphological similarities suggest that Halmyrapseudes and Pseudohalmyrapseudes are sister taxa.

Idionyxpseudovictor sp. nov. from Fujian, China (Odonata: Anisoptera: Corduliidae).

A new species of the genus Idionyx Hagen, I. pseudovictor sp. nov. from Fujian, China is described from the female, illustrated and diagnosed from its congeners. Description of the final stadium larva of the new species is also provided. The new species is closely similar to female I. victor. There are a series of relatively minor colour and pattern differences between these two female adults, as well as a series of obvious structural differences in larvae of these two species. The female adult of the new species can be separated from that of I. victor by the following characters: (1) labrum entirely yellow; (2) distal end of ventral synthorax entirely yellow; (3) abdominal S1-2 with complete middorsal yellow stripe; (4) valvula vulvae pointed triangularly, not projecting beyond apical border of 8th tergite. The larva of the new species can be separated from that of I. victor by the following characters: (1) body dark brown, covered with dense long hairs; (2) apical border of prementum with 10 spiniform setae on each side; (3) premental setae 5+3/5+3; (4) numerous fine bristles present on median lobe; (5) inner margin of palpal lobe with 6 large projections; and (6) movable hook long and acuminate.

Avicularia rickwesti sp. nov., a remarkable new species of Avicularia (Theraphosidae: Aviculariinae) from Dominican Republic

A remarkable new species of Avicularia Lamarck, 1818, Avicularia rickwesti sp. nov., is described from Dominican Republic. Female specimens of the new species are unusual by having two very short and broad spermathecae with distal half strongly sclerotized, a feature not found in any other aviculariine. Additionally, it has the leg coxae with spiniform setae, smaller on leg I and prolateral leg II, larger, black on retrolateral leg II, prolateral and retrolateral leg III and prolateral leg IV. Males are unknown. The new species is known only from two localities, in southwestern Dominican Republic. This is the first record for the subfamily on Hispañola which is close to the northern boundary for the Aviculariinae distribution.

A New Polymorphic Species ofLeptochelia(Crustacea: Tanaidacea) from Guinea Bissau, West Africa, with Comments on Genetic Variation withinLeptochelia

Anew species of Leptochelia, namely L. africana, is described from Guinea Bissau, West Africa, following the collection of specimens during the Laboratory of Marine Community Ecology and Evolution's sampling expedition to Macaronesia and Portugal's former colonies. Genetic and morphological analysis separates this species from the other east-Atlantic species of Leptochelia, a genus known for its combination of many cryptic species, considerable intra-specific variation, and multiple morphological forms. The diagnostic characters of the female are: antennule proximal article more than 3 times as long as wide, article 2 not longer than article 3; dorsodistal spiniform seta on antennal article 2 weaker than ventrodistal; setae not arising from a process; maxilliped basis with three distal setae longer than endites, palp article 2 with outer spiniform seta arising from a process; uropod exopod biarticulated, longer than proximal endopod article; and endopod terminal article longer than other articles. The males are structurally more complicated and cannot be assigned diagnostic characters based on morphology alone. The primary males have an uniarticulated uropod exopod, whereas that of the secondary males is biarticulated.

Re-examination of the eastern Pacific and Atlantic material of Alpheus malleator Dana, 1852, with the description of Alpheus wonkimi sp. nov. (Crustacea, Decapoda, Alpheidae).

The bumpy-clawed snapping shrimp, Alpheus malleator Dana, 1852 (Alpheidae), is revised based on the recently collected and older museum material from the eastern Pacific (Panama, Ecuador), Caribbean (Panama, Puerto Rico, Trinidad & Tobago), Brazil (São Paulo), and West Africa (Cape Verde, Senegal, Guinea, Equatorial Guinea, Congo). The eastern Pacific material is assigned to A. wonkimi sp. nov., based on one morphological difference in the colour and thickness of the uropodal spiniform seta, as well as previously published molecular data. The Caribbean, Brazilian and West African material is considered to represent a single, widespread, morphologically variable, amphi-Atlantic taxon, A. malleator. Alpheus pugilator A. Milne-Edwards, 1878 is retained as ajunior synonym of A. malleator, whereas A. tuberculosus Osorio, 1892, A. malleator var. edentatus Zimmer, 1913 and A. belli Coutière, 1898, the latter two based on juvenile specimens, are tentatively placed in the synonymy of A. malleator. Illustrations, including colour photographs, are provided for A. wonkimi sp. nov. and A. malleator and their morphological variability is discussed and illustrated.

Tanaidacea from Brazil: III. new records and description of a new species collected from REVIZEE-NE Program

A new species of Paratanais Dana, 1852, Paratanais coelhoi sp. nov., is described and new records for Paradoxapseudes intermedius (Hansen, 1895), Intermedichelia gracilis Guţu, 1996, Vestigiramus sp., Nototanoides cf. trifurcatus Sieg and Heard, 1985, Biarticulata sp. and Arhaphuroides sp. are provided from northeastern Brazil based on collections from the REVIZEE-NE Program. This raises the number of tanaidacean species from the Brazilian coast from 45 to 49. Paratanais coelhoi sp. nov. shares morphological features such as habitus shape, maxilliped palp setation, and cheliped proportions with P. oculatus (Vanhöffen, 1914), P. martinsi Bamber and Costa, 2009, P. tara Bird, 2011 and P. euelpis Barnard, 1920. The new species can, however, be distinguished by a unique combination of characters including: pleonites 1-4 with lateral circumplumose setae while the 5th with simple seta only; antennule article 1 stout; cheliped propodus with one specialized outer 'S'-shaped broad seta; pereopod 1 merus length with 1.7 times as long as wide; pereopod 2 merus without ventral spiniform seta; uropodal endopod biarticulate, exopod uniarticulate as well as other characters.

Description of the final stadium larva of Erythrodiplax bromeliicola Westfall 2000 (Odonata: Libellulidae) with notes on variation in adults from Cuba

The final stadium larva of Erythrodiplax bromeliicola Westfall is formally described and illustrated. The light brown scape and pedicel and creamy pale flagellum of the antenna, plus the abundant short, reddish, spiniform setae on the integument of the body surface and epiproct, comprise an exclusive combination of characters in the larva of E. bromeliicola. Information on larval habitat and a key for the larvae of the five Erythrodiplax species occurring in Cuba are provided. Details on morphological variation of an adult population from Cuba are also provided.

The shrimp family Pseudochelidae De Grave & Moosa, 2004 (Crustacea, Decapoda, Caridea) in Brazil, with the description of a new species

A new species of the caridean shrimp genus Pseudocheles Chace & Brown, 1978 is described from an offshore localityabout 160 km east of the Rio Doce estuary in Espírito Santo, Brazil. Pseudocheles falsapinca sp. nov. is the fourth speciesin the genus, differing from its three congeners, P. enigma Chace & Brown, 1978, P. chacei Kensley, 1983 and P. neutraDe Grave & Moosa, 2004, by the combination of the following features: antennal tooth minute or absent, fifth pleuronwith acute posterior tooth, carpus of third, fourth and fifth pereiopod with robust spiniform seta, coxa of third and fourthpereiopods without acute projection mesially, rostrum with five dorsal teeth, all anterior to post-orbital margin, and thirdmaxilliped with rounded, epipod-like structure. The new species is the deepest species of Pseudocheles reported so far,with both type specimens dredged at a depth range of 68–71 m. Pseudocheles falsapinca sp. nov. also represents the first record of Pseudocheles and the family Pseudochelidae De Grave & Moosa, 2004 for Brazil and the South-West Atlantic.

Tanaidacea (Tanaidacea: Crustacea) from Brazil. IV. A new genus and two new species from the family Leptocheliidae

This study is based on the material collected from REVIZEE Program and under the Petrobrás oil-exploration programs.These collections revealed a number of representatives from the family Leptocheliidae in its broadest sense, with descrip-tions of one new genus, Makraleptochelia n. gen., and two new species, M. potiguara n. sp. and Intermedichelia jesserin. sp. The new genus appears to be closely related to Konarus-Parakonarus-Pseudoleptochelia complex of species anddiffers mainly in the extremely elongated habitus of the male. Intermedichelia jesseri is only the second recorded speciesof this genus and is separated from the other species by having two distal simple setae on the lateral projections of pere-onite 3, two distal simple setae on the maxilliped basis, one ventrodistal spiniform seta on the merus-carpus-propodus ofpereopod 3, and pereopods 4 and 5 propodus with one dorsodistal simple seta marginally longer than dactylus and unguis combined. Intermedichelia is here included in the family Leptocheliidae.

Two new species of Atlantocuma (Crustacea: Cumacea), and a new genus and species from Japan, Northwest Pacific, with observations on the degeneration of mouthparts in ovigerous females

Two species of the cumacean genus Atlantocuma from the southern coast of Honshu, Japan, 781–861 m depth, A. gamoisp. nov. and A. ojii sp. nov., and Pseudopicrocuma japonicum gen et sp. nov. from Nansei Islands, 566–1769 m depth,are described. Atlantocuma gamoi is characterized by (1) carapace elevated in preparatory and ovigerous female, (2)antero-lateral angle of carapace with 3 teeth in females, and (3) pseudorostrum of carapace of adult males truncate,anterolateral angle without teeth. Atlantocuma ojii is characterized by (1) carapace not elevated in preparatory females,but elevated in ovigerous females, (2) inferior margin of carapace in ovigerous female serrated for entire length, (3)pseudorostrum of carapace in adult males truncate, (4) uropod exopod with 1–2 spiniform setae on inner margin, exceptfor subterminal one. The new genus Pseudopicrocuma, which is similar to Picrocuma from shallow waters of easternAustralia, is characterized by (1) well-developed exopods present on maxilliped 3 and pereopods 1–3 in both sexes, (2)antenna 1 of adult males with many aesthetascs-like sensory setae on peduncle articles 2 and 3, (3) male antenna 2 ofclasping form, and (4) uropod slender, peduncle shorter than rami. Pseudopicrocuma shows affinity to Atlantocuma exceptfor (1) arrangement of well-developed exopods on pereopods, (2) male antenna 2 flagellum of clasping form, and (3)uropod peduncle shorter than rami. In addition, P. japonicum and the new Japanese Atlantocuma species are characterizedby a similar trend in degeneration of mouthparts (mandibles – maxillipeds 2) in ovigerous females, suggesting a ratherclose relationship of these genera with quite different arrangements of exopods on pereopods. These 2 genera are currentlyplaced in Nannastacidae. Other possible relatives of Pseudopicrocuma are Spilocuma (Bodotriidae) and Claudicuma (Nannastacidae).

Review of the genus Neobuthus Hirst, 1911 with description of a new species from Ethiopia (Scorpiones: Buthidae)

We define key characters distinguishing between the genera Neobuthus Hirst, 1911 and Butheolus Simon, 1882. Butheolus ferrugineus Kraepelin, 1898 is transferred to the genus Neobuthus which includes only African species, in contrast to the genus Butheolus which now includes only species inhabiting the Arabian Peninsula. Neobuthus awashensis sp. n. from Ethiopia is described and compared with two closely related species, Neobuthus ferrugineus (Kraepelin, 1898) comb. n. and Neobuthus berberensis Hirst, 1911. Recent collection of 78 specimens enabled direct comparisons of all three closely related species from their respective localities and discovery of characters hitherto not apparent from discolored specimens preserved for many years in alcohol. We photographically illustrate true coloration and pubescence for these three species, provide first information about their ecology, and present photographs of their habitats and localities. Neobuthus berberensis Hirst, 1911, is lightest colored with pubescence nearly absent, and is adapted to sandy desert conditions in the vicinity of Berbera City (Somaliland). Rocky deserts in Djibouti, Ethiopia (first report), Somaliland and Somalia host the widely distributed Neobuthus ferrugineus (Kraepelin, 1898) comb. n., which varies in color and bears sparse long setae (female) or spiniform setae (male). Neobuthus awashensis sp. n. is the darkest-colored of the three and possesses pubescence similar to N. ferrugineus comb. n., from which it differs in having a longer and narrower pedipalp femur. We document strong sexual dimorphism in all three species, the lack of knowledge of which had caused the female holotype of Neobuthus ferrugineus (Kraepelin, 1898), comb. n. and the male holotype of Neobuthus berberensis Hirst, 1911 to be placed in different genera Butheolus Simon, 1882 and Neobuthus Hirst, 1911

Akanthoparapseudes alfaroae, a new genus and species of apseudomorphan tanaidacean (Crustacea: Malacostraca: Peracarida) from Puerto Rican coastal waters

Akanthoparapseudes alfaroae, n. gen., n. sp., is described from material collected at a depth of 28 m off Culebra Island on the eastern coast of Puerto Rico. The new genus, which is tentatively placed in the family Parapseudidae, is distinguished from other parapseudid genera by a combination of characters, including: (1) pereonites 2 to 6 subquadrate with posterolateral margins each armed with small, but distinct spiniform seta, (2) the first pleonite with anterodorsal margin lacking a distinct transverse row of small setulate setae, (3) maxilliped palp having distolateral margin of article 2 with a strongly developed spiniform seta, (4) pereopod 1 with a reduced coxal process and with anterior margin of basis armed with a strongly developed, acute, spiniform seta, (5) pereopod 2 with basis having well-developed acute spine on mid anterior margin (6) ischium of pereopods 2 to 6 having anterior margin armed with one, occasional two, well-developed narrow, acute spines, (7) pereopod 4 with dactylus, not greatly reduced, but having some adjacent setae of equal or slightly greater length. The new genus is further characterized by the presence of distinctive, blunt-tipped, crenulate, spiniform setae on the carpus and propodus of pereopods 4 to 6; similar to those reported for some species of the apseudid subgenus Bunakenia (Extensibasella) . A key for the separation of the parapseudid genera within the Tribe Parapseudini that lack a distinct transverse row of setae on the first abdominal segment is presented. Akanthoparapseudes appears to share several synapomorphies with some species of the apseudid genus Bunakenia, suggesting the possibility that these two genera may represent transitional links between the families Apseudidae and Parapseudidae. Several other important overlapping characters that appear to erode the basic differences between the two families are discussed.

Akanthoparapseudes alfaroae, a new genus and species of apseudomorphan tanaidacean (Crustacea: Malacostraca: Peracarida) from Puerto Rican coastal waters

Akanthoparapseudes alfaroae, n. gen., n. sp., is described from material collected at a depth of 28 m off Culebra Island on the eastern coast of Puerto Rico. The new genus, which is tentatively placed in the family Parapseudidae, is distinguished from other parapseudid genera by a combination of characters, including: (1) pereonites 2 to 6 subquadrate with posterolateral margins each armed with small, but distinct spiniform seta, (2) the first pleonite with anterodorsal margin lacking a distinct transverse row of small setulate setae, (3) maxilliped palp having distolateral margin of article 2 with a strongly developed spiniform seta, (4) pereopod 1 with a reduced coxal process and with anterior margin of basis armed with a strongly developed, acute, spiniform seta, (5) pereopod 2 with basis having well-developed acute spine on mid anterior margin (6) ischium of pereopods 2 to 6 having anterior margin armed with one, occasional two, well-developed narrow, acute spines, (7) pereopod 4 with dactylus, not greatly reduced, but having some adjacent setae of equal or slightly greater length. The new genus is further characterized by the presence of distinctive, blunt-tipped, crenulate, spiniform setae on the carpus and propodus of pereopods 4 to 6; similar to those reported for some species of the apseudid subgenus Bunakenia (Extensibasella) . A key for the separation of the parapseudid genera within the Tribe Parapseudini that lack a distinct transverse row of setae on the first abdominal segment is presented. Akanthoparapseudes appears to share several synapomorphies with some species of the apseudid genus Bunakenia, suggesting the possibility that these two genera may represent transitional links between the families Apseudidae and Parapseudidae. Several other important overlapping characters that appear to erode the basic differences between the two families are discussed.

The species of Grammostola (Araneae: Theraphosidae) from Central Argentina: taxonomy, distribution, and surface ultrastructure of coxal setae

Three species of Grammostola (Araneae, Mygalomorphae, Theraphosidae) from central Argentina are redescribed and illustrated and their geographic distributions are reported. A new synonymy between G. vachoni Schiapelli & Gerschman 1961 and G. schulzei (Schmidt 1994) n. syn. is proposed. We did not find zones of co-occurrence with the three species but, in several localities, we found two Grammostola species in sympatry. The surface ultrastructure of three types of coxal setae was studied by scanning electron microscopy (SEM). Two morphological types of spiniform setae were found on the coxae. The first type consisted of short and strong piriform setae, with the surface completely covered by ridges, and the second type consisted of long and thinner spiniform setae, with a piriform basal portion. The basal portion of the setae had ridges, the central portion was smooth and the apical zone had numerous short barbs with curved tips. The different types of setae found in these Grammostola species are clearly distinguished, and could be new useful character to diagnose at least these species. In combination with other characteristics, these characters could probably help to solve the problems in other species of this difficult genus if not also other genera.