Spiniform Setae Research Articles

First record of Acarophenacidae (Acari: Heterostigmata) from Mexico, with description of a new species of Paracarophenax associated with Cerambycidae (Insecta: Coleoptera)

Paracarophenax (Acari: Heterostigmata: Acarophenacidae) comprises eight distinct species of egg parasitoids associated mainly with various beetles, distributed across different global regions. In this study, a new species of Paracarophenax was found associated with cerambycid beetles´ collection samples deposited in the Colección de Insectos de la Universidad de Morelos, Morelos, Mexico. The aim of this paper is to describe the ninth species of the Paracarophenax, and provide an updated taxonomic key of the genus. The new species can be separated from others congeners by the presence of one spiniform seta on genu II, the seta l’ on femur I slightly spatulate, one seta on femur III, setae e slightly longer than f, and the distance between setae e and f slightly longer or equal to the distance between setae h<sub>1</sub> and h<sub>2</sub>. This study reports the family Acarophenacidae for the first time from Mexico, and the genus Paracarophenax from the Neotropical Region.

New species of Neomachilellus Wygodzinsky 1953 (Insecta: Archaeognatha: Meinertellidae) from Madre de Dios, Peru

This study describes a new species of jumping bristletail, Neomachilellus mercurialis sp. nov., discovered during a research expedition at the Los Amigos Biological Station in Madre de Dios, Peru. The specimens could not be morphologically assigned to any known species within the genus Neomachilellus s. str. Wygodzinsky 1953. Morphological examination revealed distinct differences in various characters, morphometric measurements, and pigmentation patterns compared to other species. The new species exhibits submedian, widened, oval-shaped ocelli, pigmentation on articles I‒VII of the maxillary palpi, and strong pigment on the femora, tibiae, and tarsi of the legs. Notably, femora and tibiae lack spines or prominent spiniform setae, while the tarsi feature spine-like setae characteristic of the nominal subgenus. The newly discovered species shares a close relationship with other taxa of Neomachilellus, specifically belonging to the muticus-group of species. Urgent taxonomic revision and molecular studies are warranted for this genus, emphasizing the ongoing challenges in understanding Archaeognatha.

Three new species of Paratanaoidea (Crustacea, Tanaidacea) from the South China Sea.

Three new crustacean species of the order Tanaidacea are described from the South China Sea. Alloleptochelia falciformes sp. nov. (Family Leptocheliidae) can be distinguished from the most similar species, A. evansi (Edgar, 2012), by the much stouter body, and fewer articles on the antennule flagellum and relatively longer pereopods 46 dactylus of the male. Kalloleptochelia multiarticulata sp. nov. (Family Leptocheliidae) can be easily differentiated from its congeners by the male having significantly more antennule flagellum articles, a two-articled uropod exopod, one additional dorsal seta on the pereopods 23 merus, and one additional spiniform seta on the pereopod-6 carpus. Paranesotanais incisus sp. nov. (Family Nototanaidae) differs from its only congener, P. longicephalus Larsen & Shimomura, 2008, by the female having one robust inner seta on the palm of the cheliped propodus, and the male having one long and conspicuous notch extending from the outer surface to the ventrodistal corner on the cheliped carpus. Morphological keys and comparison tables of all known species of the genera Alloleptochelia and Kalloleptochelia, as well as a key of the genus Paranesotanais, are provided.

On a Remarkable New Genus and Species of Alpheid Shrimps (Malacostraca: Decapoda: Caridea) from the Tropical Western Atlantic

Synalpheopsis gen. nov. is established for a remarkable new alpheid species, Synalpheopsis laureae sp. nov., presently known only from the male holotype collected at 111–162 m east of La Désirade, Guadeloupe, Lesser Antilles. Synalpheopsis gen. nov. peculiarly combines features of two genera, Alpheopsis Coutière, 1897 and Synalpheus Spence Bate, 1888; however, it is presumably closer to the former genus. The new genus is characterised by the moderately developed orbital hoods, well-developed rostrum and orbital teeth, sixth pleonite without articulated flap, tip of the third maxilliped with crown of spiniform setae, chelipeds with two strong teeth on distolateral margin and lacking snapping mechanism on finger cutting edges, and gill formula without mastigobranchs and setobranchs.

Nototanoides oliveri, a new sponge-dwelling nototanaid tanaidacean (Crustacea, Tanaidomorpha, Tanaidacea) from eastern Gulf of Mexico, with an illustrated taxonomic key, and the first record of harpacticoid copepods within the marsupium of ovigerous female tanaids.

A new species of tanaidacean, Nototanoides oliveri sp. nov. from the eastern part of the Gulf of Mexico is described and illustrated. The new species appears to be most closely related to the recently described western Atlantic species, N. polytrichus. It can be easily distinguished from that species, as well as the other members of the genus, N. trifurcatus and N. ohtsukai, by a combination of characters, including: (1) female antennular article-3 with up to 11 aesthetascs (2) female maxilliped palp article-2 with multifurcate spiniform seta and (3) male cheliped basis having mid-ventral margin swollen, forming a rounded apophysis/protuberance. In addition, an unknown living harpacticoid copepod is reported for the first time within the marsupium of ovigerous females of Tanaidacea. An illustrated key to the four species comprising the genus Nototanoides is presented.

Two new species in Leptocheliidae (Crustacea: Peracarida: Tanaidacea) from Japan, with notes on their phylogenetic position and aspects of morphology

We describe two new species of leptocheliid tanaidaceans, Chondrochelia sublitoralis sp. nov. and Neoleptochelia japonica sp. nov., from Japan. Chondrochelia individuals were collected from 113 to 185 m depth in the Kumano Sea. Chondrochelia sublitoralis sp. nov. resembles Chondrochelia africana, Chondrochelia corsica, Chondrochelia taitungensis, and Chondrochelia tanykeraia in having females with slender chelipeds but differs from them in the length ratio of antennular articles and the setal pattern on maxillipeds, cheliped, pereopods 4–6, and pleopods. Males differ from Chondrochelia durbanensis, for which information on females is lacking, in having pereopod-1 propodus lacking ventrodistal spiniform setae and a uniarticulate uropodal exopod. Chondrochelia sublitoralis sp. nov. varies intraspecifically in the number of female antennular articles, five in larger and four in smaller females. Neoleptochelia japonica sp. nov., collected from the coast of Okinawa Island, differ from Neoleptochelia javaensis (previously the sole species in Neoleptochelia) in the setal pattern on antennae, maxillipeds, cheliped, and pleopods in females; and that on the cheliped in males. Male pereopods 1–3 show a unique subchelate condition that we speculate may function for clasping during copulation. Several females in both species had the second thoracomere demarcated on the carapace, whereas others did not. Cytochrome c oxidase subunit I (COI) gene sequences determined for C. sublitoralis sp. nov. and N. japonica sp. nov. showed intraspecific K2P distances of 0–0.4% and 0–0.5%, respectively. We inferred the phylogenetic positions of the two species in Leptocheliidae based on COI data.

A new deep-water species of Discias Rathbun, 1902 (Decapoda: Caridea: Disciadidae) from the Gulf of Aqaba, northern Red Sea.

A new species of the caridean shrimp genus Discias Rathbun, 1902 is described from the Gulf of Aqaba in the northern Red Sea off the coast of Saudi Arabia. Discias forsskali sp. nov. is unique within the genus Discias, combining the following morphological features: (1) rostrum elongate, triangular, pointed distally, non-lanceolate, with serrations on the lateral margins extending onto the orbital margin; (2) posterodorsal margins of all pleonites smooth, unarmed; (3) mandible with well-developed, biarticulated palp; (4) dactylus of third to fifth pereiopods with row of spinules on ventral margin, dactylus of fifth pereiopod smooth dorsally; (5) uropodal exopod with straight, non-serrated lateral margin; and (6) posterior margin of telson with nine (four pairs + one) spiniform setae. The holotype and single known specimen of the new species, an ovigerous female, was collected by ROV at a depth of 387.4 m.

Mysid subfamily Boreomysinae (Crustacea: Mysida: Mysidae) in the southeast Australian deep-sea

The deep-water mysid crustaceans of Australia have been barely known. Recent explorations of RV Investigator (CSIRO) in the southeast Australian waters discovered a unique fauna. In this special study of the marine subfamily Boreomysinae (family Mysidae) in Australia, five species from both genera Boreomysis and Neobirsteiniamysis are reported, including two new species for science: B. inopinata sp. nov., B. sibogae, B. sphaerops, B. urospina sp. nov. and N. inermis. Among the members of the subfamily, only B. sibogae has been previously known from Australia. The genus Neobirsteiniamysis and its bipolar-amphitropical species N. inermis are firstly recorded in Australia. Boreomysis inopinata sp. nov. has additional spinules on the outer spine of the antennal scale, which are not found in other species of the subfamily. Boreomysis urospina sp. nov. has the longest first segment of the uropodal exopod, laterally terminated by three spiniform setae; and its uropodal endopod is armed with up to five medial spiniform setae, the largest number in the subfamily. This species is included in a newly established subgenus Petryashovia subgen. nov., which unites epi-mesopelagic boreomysines, lacking the rostral projection, having rather small ventrolateral lobes of the carapace, and the 1-segmented propodus of the pereopods. The subfamily and generic diagnoses are updated. Additionally, a fragment of the mtDNA COI gene was sequenced for most of the studied species.

A new deep-sea palaemonid shrimp assigned to Periclimenes Costa, 1844 (Decapoda: Caridea) from the West Mariana Ridge, northwestern Pacific

A new palaemonid species, Periclimenes variabilis, is described and illustrated on the basis of four specimens from the Ritto Seamount, West Marina Ridge, northwestern Pacific, at depths of 642-666 m. Specimens of the new species were collected with an unidentified hexacoral of Primnoidae (Cnidaria), an antipatharian octocoral Leiopathes sp. (Cnidaria), and an unidentified crinoid (Echinodermata), suggesting association with those invertebrates. Morphological comparison and molecular phylogenetic analyses using the mitochondrial 16S ribosomal RNA and cytochrome C oxidase subunit I genes indicate that the new species is closest to Periclimenes uniunguiculatus Bruce, 1990 although the possession of more than two spiniform setae on either side of the telson in the new species is consistent with the generic diagnosis of Bathymenes Kou, Li & Bruce, 2016. In reference to the close relationship to the species currently assigned to Periclimenes Costa, 1844 and the unsettled taxonomy of the genus, the new species is provisionally assigned to Periclimenes. Differentiating characters between the new species and closely related taxa are discussed.

A new species of the genus Eutrichopagurus Komai, 2015 (Crustacea: Decapoda: Anomura: Paguridae) from a submarine cave in the Ryukyu Islands, southwestern Japan

A new hermit crab species of the family Paguridae is described on the basis of two male specimens from Hedo Dome, a submarine cave located on the north coast of Okinawa Island, Ryukyu Islands, southwestern Japan. The assignment of the new species to the genus Eutrichopagurus Komai, 2015 is based on the structure of the gills and right male sexual tube, the article 3 of the antennular peduncle with a prominent tuft of setae on the dorsodistal margin, and the posterior lateral margins of the telson each bearing a prominent tuft of setae. Among two known congeners, Eutrichopagurus crassoculus n. sp. may be closer to the type species of the genus, E. shirakawai Komai, 2015, in having greatly reduced corneas, basally bearing sparse setae, and no small corneous spines or spiniform setae on the dorsal surface of the meri of the ambulatory legs, but is distinguishable by the morphology of the ocular peduncles, ocular acicle, antennular peduncle, and chelipeds.

A new genus and species of Apseudidae, and a new species of Bunakenia (Crustacea: Tanaidacea: Apseudomorpha) from the Northwest Atlantic and Gulf of Mexico.

Examination of material from the Campeche region of the southern Gulf of Mexico revealed the presence of a new genus and species of Apseudidae that appears to be transitional between Bunakenia Guu and Apseudes Leach sensu lato. This new taxon, Pseudobunakenia anablesis n. gen., n. sp. is found throughout the Gulf of Mexico (GOM) and Northwest Atlantic as far north as South Carolina. It is known in the literature under the designation Apseudes spinosa Sars sensu Dawson and Apseudes sp. A (Heard et al.). Also, Bunakenia hamata n. sp. is described from offshore Georgia and is distributed from the Florida Gulf Coast and the Northwest Atlantic as far north as South Carolina. It is known in the literature under the designation Bunakenia sp. A (Heard et al.) and is the only known species of that genus in the GOM/NW Atlantic. It can be distinguished from its congeners by a combination of characters such as the pereonites having posterolateral apophyses, the antennule first peduncle article denticulate, the antennule accessory flagellum having five articles, and the first pereopod having four ventral propodal spiniform setae. A key to the known species is presented.

A new brackish tanaidacean, Sinelobus kisui sp. nov. (Crustacea, Peracarida, Tanaidacea), from Japan, with a key to Sinelobus species and barcode information from two loci

We describe the new brackish tanaidid species Sinelobus kisuisp. nov. from Hagi, Yamaguchi, Japan. Sinelobus kisui is similar to S. barretti and S. vanhaareni in having antennal article 2 with one outer distal seta, the dorsodistal crotchet on pereopods 2 and 3 carpi shorter than half propodus length, and pereopodal carpi 2–6 with five distal crotchets, but differs from them in having (1) the inner of two ventro-subdistal circumplumose setae on the maxillipedal endite longer than the outer; (2) the maxillipedal endite with one mid-inner spiniform seta; (3) the pereopod-1 propodus with one middle setulate seta; and (4) the pleopod-1 protopod lacking inner plumose setae. Our study confirmed that character states of the chelipeds in strongly dimorphic males are useful in Sinelobus taxonomy. We determined partial sequences for the cytochrome c oxidase subunit I (COI; cox1) and 18S rRNA (18S) genes in S. kisui for future DNA barcoding and phylogenetic analyses. Morphological and/or molecular data reveal that S. kisui also occurs in Kagawa and Osaka, Japan. A key to species in Sinelobus is provided.

Morphological Differentiation of Ventral Tarsal Setae and Surface Sculpturing of Theraphosids (Araneae: Theraphosidae) With Different Types of Lifestyles

Abstract The ventral surfaces of tarsi in spiders in the infraorder Mygalomorphae group play a key role in locomotion and burrow and nest construction. In our research, we analyzed the diversity of setae and patterns of sculpturing on tarsi in three species with different life strategies: a burrowing spider Brachypelma smithi (F. O. Pickard-Cambridge, 1897), a ground-dwelling spider, Pterinochilus murinus Pocock, 1897, and a arboreal spider, Poecilotheria regalis Pocock, 1899. We showed the presence of three types of setae on the ventral side of tarsi: plumose setae, short-haired spiniform setae, and spirally striated setae. Plumose setae were differentiated within a tarsus and their apical sections among the studied species, while the microtriched ensiform and spirally striated setae did not differ. All setae were characterized by a similar structure. Little differentiation was observed in the number and location of setae on the tarsi of the studied species. Spirally striated setae were absent in the burrowing spiders. In contrast, the shape and size of the sculpturing pattern varied among the studied species. The greatest differentiation was found in the burrowing and ground-dwelling spiders, while the smallest differentiation was found in the arboreal spider. We discuss our findings in relation to preferred habitats, the biology of the spiders, and adaptation of sculpturing and setae on spider feet to surface type. The morphology and diversity of setae and sculpturing patterns on the ventral side of tarsi in P. murinus was reported for the first time.

Ontogenetic instars of Gymnodamaeus uslaminorum sp. nov. (Acari, Oribatida, Gymnodamaeidae) from Russia

ABSTRACT A new species of the genus Gymnodamaeus (Oribatida, Gymnodamaeidae) is described from litter with needles in mixed forest (spruce-birch-cedar) of Western Siberia, Russia, based on adult and juvenile instars. The adult instar of Gymnodamaeus uslaminorum sp. nov. is characterized by the tuberculate cerotegument on the body; short, spiniform interlamellar seta inserted on cylindrical tubercle; long bothridial seta with a flattened head; dorsosejugal region with one pair of large tubercles; anterodorsal notogastral part with slight ridges forming П-like structure; six/seven pairs of setiform notogastral setae; parastigmatic tubercle Sp; one pair of anogenital concavities; and the absence of discidium and parastigmatic tubercle Sa. The identification keys to known larvae and nymphs of Gymnodamaeus are presented. http://www.zoobank.org/urn:lsid:zoobank.org:pub:FBE0387D-A69A-488C-952C-16054CB82434.

Description of the larva of Argia cuprea (Hagen, 1861) with notes on its phylogenetic affinities (Odonata: Coenagrionidae).

The larva of Argia cuprea (Hagen, 1861) is described and figured. It falls into the group of Argia larvae with prominent ligula and one palpal seta, but it differs from its closest relatives by a combination of features such as male gonapophyses reaching posterior ventral margin of S10; dorsal and ventral margin of paraproct with long, abundant, white, delicate setae on distal 0.40; tip of paraproct 20% its total length; lateral surface of paraproct with abundant spiniform setae restricted to the triangular, yellowish-brown, slightly sclerotized area along the inflated area. It appears closely related to A. oenea Hagen in Selys, 1865 and A. orichalcea Hagen in Selys, 1865 larvae.

New and interesting palpigrades (Arachnida, Palpigradi) of the genera Koeneniodes Silvestri, 1913 and Prokoenenia Börner, 1901 from Asia.

Two new species of palpigrades are described: a soil-dwelling species of the genus Koeneniodes Silvestri, 1913 from a broadleaf forest in Tibet and an extraordinary cave-dwelling species from Jinhua cave in China belonging to Prokoenenia Börner, 1901. Koeneniodes tibetanus sp. n. is related to Koeneniodes spiniger from Thailand. The two species share the presence of four thick and spiniform setae on the second lobe of the female genitalia; they differ in the number of thick setae on opisthosomal sternite IV, the number of cheliceral teeth, the coxal setal formula, and the morphology of the spiniform setae. Prokoenenia sarcodactylica sp. n. is based on an immature female from Jinhua Cave, Beijing. The presence of 18 finger-shaped blades in the lateral organs-unique among palpigrades , the large body size (2150 μm) and the extremely long basitarsus IV (205 μm) indicate that the new species is the first undoubtedly caveadapted Prokoenenia. This is also the first record of the genus Prokoenenia from China.

Antikuna, a new genus with seven new species from Peru (Araneae: Theraphosidae: Theraphosinae) and the highest altitude record for the family

ABSTRACT Antikuna, a new genus from Peruvian Andes, was proposed, diagnosed and described, to include seven new species: Antikuna cernickai sp. nov., A. cimrmani sp. nov., A. cyanofemur sp. nov., A. majkusi sp. nov., A. sapallanga sp. nov., A. urayrumi sp. nov. and A. valladaresi sp. nov. Antikuna gen. nov. is characterised by having the type III urticating setae concentrated in one dorsal patch, ventral side of maxillae with short spiniform setae in apical half, the male bulb carrying four keels, prolateral superior, prolateral inferior, apical and subapical keel terminating in a short tooth, and the female spermathecae consisting of two separate divergent seminal receptacles, carrying one or more ventral keels, and dorsally with distinct oval apical lobe, which is narrower than the receptacle neck. In the males of Antikuna gen. nov. the flexion of metatarsi I is between both branches of tibial apophyses and prolateral cymbial lobe is distinctly larger than retrolateral one. Antikuna gen. nov. inhabits altitudes above 3,800 m a.s.l. and A. valladaresi sp. nov. was found in the altitude of 4,689 m a.s.l. representing a new highest altitude record for the family Theraphosidae. urn:lsid:zoobank.org:pub:537E9E34-2888-4F99-B4A9-74A965F0E456

A new species of the genus Eucalliaxiopsis Sakai, 2011 from the South China Sea (Decapoda, Axiidea, Eucalliacidae)

Abstract Eucalliaxiopsis liui sp. nov. is described from a specimen taken from the South China Sea. The new species differs from other species of Eucalliaxiopsis in the combination of a telson with a transverse posterior margin, without a transverse row of spiniform setae, and a hook on the upper margin of the carpus of the cheliped. Eucalliaxiopsis liui is unique in having a biramous female pleopod 2, its endopod slender, with finger-like appendix interna, and a slender segmented exopod.

A new species of Zeuxo (Crustacea: Peracarida: Tanaidacea) from Japan, with remarks on carapace pigmentation as a potentially useful taxonomic character

ABSTRACT We describe Zeuxo ezoensis sp. nov. from Hokkaido, Japan. This species closely resembles Z. phytalensis, Z. shitipingensis and Z. turkensis in having the pleopodal endopod with one inner plumose seta, maxillipedal palp article 4 with one outer simple seta, the left mandible with a wide, denticulate lacinia mobilis and one bifurcate accessory seta, and the right mandible with a peg-like lacinia mobilis and two accessory setae. It differs from them in having (1) antennal article 6 longer than wide, (2) the distal region of the maxillipedal endite with four spiniform setae and two circumplumose setae, (3) maxillipedal palp article 2 with one outer simple seta, (4) the chelipedal carpus with three or four dorsodistal simple setae, (5) the chelipedal dactylus with one inner simple seta, (6) the pereopod-1 basis with one or two ventrodistal simple setae, (7) the pereopod-1 carpus with one ventrodistal simple seta, and (8) the uropod with four or five articles (basal article plus three or four ramus articles). Partial nucleotide sequences for the cytochrome c oxidase subunit I (COI) gene (655 nt) from Z. ezoensis specimens from four localities in Hokkaido showed Kimura 2-parameter (K2P) divergences of 0–0.5% and 0.6–1.5% within and between populations, respectively. Based on the COI data, we examined the phylogenetic position of Z. ezoensis within Zeuxo. Six specimens used for morphological observations and 10 specimens used for COI sequencing showed a similar dorsal pigmentation pattern on carapace. We briefly discuss the validity of using this pattern as a diagnostic character in Zeuxo taxonomy. http://zoobank.org/urn:lsid:zoobank.org:pub:6CB565DB-DAFF-41EF-A06D-EAAE2F619C31

Paradoxapseudes shimojiensis sp. nov. (Crustacea: Tanaidacea: Apseudidae) from a submarine limestone cave in Japan, with notes on its chelipedal morphology and sexual system

ABSTRACTWe describe Paradoxapseudes shimojiensis sp. nov. from a submarine limestone cave at Shimoji-jima Island, Ryukyu Islands, southwestern Japan. This species resembles five species (P. basibidens, P. bassoprofundo, P. bermudeus, P. edgari, and P. heroae, among 17 congeners) that bear a long pleotelson, but differs from them in having (i) a naked antennal article 1, (ii) the maxillipedal basis with one inner distal plumose seta, (iii) the chelipedal basis with one dorsodistal and one ventro-subproximal simple setae, (iv) the pereopod-1 basis with four dorsal simple setae longer than the width of the pereopod-1 basis, but without ventrodistal spiniform setae, (v) the pereopod-1 merus with three mid-inner ventral simple setae, and (vi) the pleopodal protopod with two inner plumose setae. We determined partial nucleotide sequences for the cytochrome c oxidase subunit I (COI) and 18S rRNA (18S) genes in P. shimojiensis for future use in DNA barcoding and phylogeny. Paradoxapseudes shimojiensis has serial ridges on the inner surfaces of the left and right chelipedal bases that quite resemble the stridulatory organs in harvestmen (Opiliones); by analogy, we speculate that these ridges may be stridulatory sound-producing organs. Two specimens had both a fully-developed marsupium and genital cone, suggesting that P. shimojiensis is simultaneously hermaphroditic.http://zoobank.org/urn:lsid:zoobank.org:pub:391C3C0F-8845-4496-A27D-936384F9E59D