Tactile Setae Research Articles

Species groups, subgroups, and key to world species of the genus Schizotetranychus Trägårdh, 1915 (Acari, Prostigmata, Tetranychidae).

After a comprehensive taxonomic assessment of descriptions/ illustrations of all known (118) species of the spider mite genus Schizotetranychus Trägårdh (Acari: Prostigmata: Tetranychidae), five species groups are proposed based on the number of tactile setae on tibia II in female, i.e., vermiculatus with four setae (four spp.), schizopus with five setae (52 spp.), spireafolia with six setae (10 spp.), asparagi with seven setae (20 spp.), and bambusae with eight setae on tibia II (22 spp.). The species group schizopus is further divided into three species subgroups based on tactile setae on tibia I: schizopus with eight/ nine setae (21 spp.), andropogoni with seven setae (26 spp.), and taquarae with six tactile setae excluding the solenidion on tibia I (five spp.). Eight Schizotetranychus species were not assigned to any species group because of brief descriptions and/ or illustration and without information on the number of tactile setae on tibiae I and II. Moreover, two Schizotetranychus species, S.gausus Baker & Pritchard and S.luculentus Tseng that have six setae/ structures including a spinneret and a solenidion on the palp tarsus, are provisionally transferred to the genus Stigmaeopsis Banks. Finally, keys to species groups and subgroups of the world species of Schizotetranychus are provided.

First Report of Tetranychus truncatus Ehara (Acari: Tetranychidae) Infesting Groundnut (Arachis hypogaea L.) in India through Morphological and Molecular Insight

Background: Red spider mite, Tetranychus truncatus Ehara (Acari: Tetranychidae) infests many agriculture and horticulture crops in India, but to date it had not been found damaging cultivated groundnut. During 2022-23, the incidence of this species was high in many groundnut growing regions of Tamil Nadu. Identification of the species is highly essential for effective management of the particular pest. Hence, the aim of this research was to identify the mite species infesting groundnut crop and describe the damage caused. Methods: Survey was carried out all over Tamil Nadu and samples of mite infested groundnut leaves were collected from field based on damage symptoms, observed and examined under Stereo zoom microscope, microslides were prepared using Hoyer’s medium and taxonomic characters were studied under phase contrast microscope. Molecular analysis was done by genomic DNA isolation, PCR amplification, sequencing and BLAST performed to check the identity with GenBank Sequences. ITS2 primer was used. Result: Red spider mite species, T. truncatus was identified first time in groundnut through both morphological characters and molecular tools. Female: Idiosomal setae longer than the interval between their longitudinal bases and gradually tapers distally. Diamond- shaped pattern of striae between e1 and f1 setal bases. Tarsus I with 4 tactile setae proximal to proximal duplex setae. Male: Aedeagus with tiny terminal knob, apparently truncate with a slight indentation on the dorsal margin.

Pseudoscirus gen. nov. of Coleoscirinae (Acari: Prostigmata: Cunaxidae) from the Amazon rainforest, Brazil, with a key to the genera of adult female Coleoscirinae

ABSTRACT The genus Coleoscirus Berlese, 1916, is revised and divided into two genera. Coleoscirus intermedius Corpuz-Raros, 1996 is designated the type species for Pseudoscirus Wurlitzer and Rocha gen. nov. This new genus is peculiar in having characteristics of both Coleoscirus Berlese, 1916 and Pseudobonzia Smiley, 1975. The general characters of Pseudoscirus Wurlitzer and Rocha gen. nov. within the subfamily Coleoscirinae Den Heyer, 1978 include the presence of a small dorsal shield that covers only the propodosoma, and having swollen apices of solenidia on tarsus I. The new genus resembles Coleoscirus species due to coxal plates I and II fused medially, forming the sternal shield, and idiosomal plates poorly developed. A new species from the Amazonic biome in Brazil, Pseudoscirus amazonae Wurlitzer and Rocha sp. nov., is also described and illustrated. The new species differs from the known species Pseudoscirus intermedius Corpuz-Raros, 1996 by basifemora II with 6 sts; propodosomal shield with a notch, and simple tactile setae c1, c2, d1, e1, f1, f2, h1 and h2 on minute sclerotised plates. urn:lsid:zoobank.org:pub:C45C0CF6-CEAB-4AF1-995F-FDCDB2062C3F

In the twilight zone-The head morphology of Bergrothia saulcyi (Pselaphinae, Staphylinidae, Coleoptera), a beetle with adaptations to endogean life but living in leaf litter.

The pselaphine Bergrothia saulcyi shows features seemingly linked with life in deep soil layers, such as greatly reduced and non-functional compound eyes, a sensorium of long tactile setae, long appendages, and flightlessness. However, the tiny beetles occur in forest leaf litter, together with a community of beetles with wings and well-developed eyes. We hypothesize that B. saulcyi moves into deep soil under dry conditions, and returns to upper layers when humidity increases again. Despite the evolutionary cost of a reduced dispersal capacity, this life strategy may be more efficient and less hazardous than moving to different habitats using flight and the visual sense in an environment periodically drying out. We also discuss cephalic features with potential phylogenetic relevance. Plesiomorphies of B. saulcyi include the presence of anterior tentorial arms, well-developed labral retractors, and a full set of extrinsic maxillary and premental muscles. Apomorphic cephalic features support clades Protopselaphinae + Pselaphinae, and Pselaphinae. A conspicuous derived condition, the clypeo-ocular carina, is a possible synapomorphy of Batrisitae and genera assigned to Goniaceritae. A complex triple set of cephalic glands found in B. saulcyi is similar to a complex identified in the strict myrmecophile Claviger testaceus (Clavigeritae). It is conceivable that glands linked with food uptake in free-living pselaphines were genetically re-programmed in ancestors of inquilines, to enable them to appease the host ants. We suggest that behavioral studies are necessary to understand the poorly known life habits of B. saulcyi. Additional information is required to explain why a species with irreversibly reduced visual sense and other adaptations typical of endogean or cave-dwelling beetles was only collected from the upper leaf litter layer.

Cystowithius ankeri sp. nov. (Arachnida: Pseudoscorpiones: Withiidae), a new pseudoscorpion from the Central Andes of Colombia

ABSTRACT A new species of the pseudoscorpion genus Cystowithius Harvey, 2004 is described based on several males and females collected in the Cordillera Central near Manizales and Villamaria, Caldas, Colombia. The type series was collected under or on the bark of Eucalyptus grandis W. Hill ex Maiden (Myrtaceae). Cystowithius ankeri sp. nov. is the fifth species in the genus, differing from its four congeners by several characters, including the position of the male sternal invaginations, the length of the movable finger of the pedipalp, and the tactile setae of tarsus IV situated subdistally. A revised identification key to the five species of Cystowithius is also presented. The first barcode (COI gene) of a species of this genus is also provided.

Complementary description of Panonychus caricae Hatzinikolis, 1984, with the resurrection of the genus Sasanychus Ehara, 1978 (Acari, Prostigmata, Tetranychidae).

A complementary description of Panonychus caricae Hatzinikolis, 1984, is presented based on the morphology of adult female and male individuals collected from fig trees (Ficus sp., Moraceae) in Greece. Morphological differences between Panonychus caricae and two closely related species, Panonychus ulmi (Koch, 1836) and Panonychus hadzhibejliae (Reck, 1947), are discussed. Panonychus caricae can be separated from two other Panonychus species using the length of the female dorsal setae in combination with the ratio between the length of female dorsal opisthosomal setae f2 and h1, and the ratio between the length of dorsal setae sc1 and h1. A phylogenetic maximum likelihood tree was constructed based on the cytochrome c oxidase subunit I (COI) gene of mitochondrial DNA (mtDNA) from 10 species of the subgenus Panonychus s.str. (including the re-described species P. caricae) and the only two species of the subgenus Sasanychus. The phylogenetic tree indicates that these 12 species are clearly separated from each other. The two subgenera, Panonychus s.str. and Sasanychus, comprise strongly supported monophyletic clades with 98% bootstrap values. The convergence of molecular and morphological data (dorsal setae set on tubercles or not, number of tactile setae on tibiae I and II, and patterns of the dorsocentral striae) suggests that Sasanychus should not be classified under the genus Panonychus. Consequently, molecular and morphological evidence supports the resurrection of the genus Sasanychus, which contains two species, S. akitanus (Ehara) and S. pusillus Ehara Gotoh, as distinct from Panonychus. A key to the world species of Panonychus and Sasanychus is also provided.

A new species of spider mite, Oligonychus neocastaneae sp. nov. (Acari: Tetranychidae), from Japan.

A new species Oligonychus neocastaneae sp. nov. is described and illustrated from Castanea crenata Sieb. et Zucc. (Fagaceae). The new species closely resembles Oligonychus castaneae Ehara Gotoh, 2007, which inhabits the same host plant, Castanea crenata, but mainly differs by the aedeagus in having a longer distal portion which forms a small sigmoid and acuminate tip, instead of having a shorter distal portion which ends in a truncate tip. Several differences were also observed between the two species in the leg setal counts of tarsus II in the male and female; the number of tactile setae and solenidia (in parentheses) was 11(1) for the female and male in the new species, but in O. castaneae this count is 12(1) for the female and 12(2) for the male. A maximum likelihood tree based on the cytochrome c oxidase subunit I (COI) gene of mitochondrial DNA (mtDNA) showed that O. neocastaneae sp. nov. was clearly separated from O. castaneae and other related species. A key to all species of the genus Oligonychus known in Japan is given.

The head of Heterogyrus milloti (Coleoptera: Gyrinidae) and its phylogenetic implications

Head structures of Heterogyrus milloti Legros, 1953 are described in detail and documented with different morphological techniques, including μ-computed tomography and computer-based 3D reconstructions. The results are compared with cephalic conditions found in other gyrinid taxa and the observed characters are interpreted and analysed phylogenetically. Nine unambiguous cephalic apomorphies support the monophyly of Gyrinidae. In addition to well-known characters like the subdivided compound eyes and highly modified antennae, this includes the very tight connection of the dorsal surface of the head with the anterior pronotal margin, the presence of a clypeofrontal gland, the separation of a lateral portion from the clypeus, and the loss of the dorsal tentorial arm. Unambiguous synapomorphies of Heterogyrus and Gyrininae sensu Miller and Bergsten (2012) are the relatively widely separated dorsal and ventral ocular subunits, the absence of tactile setae on the head capsule, the shortened mesal mandibular edge, widely separated mandibular incisivi, three rows of setae on the labrum, the enlargement of the lateral mental lobes, and the loss of the stipital muscle attached to the galea. The monophyly of Gyrininae (excl. Heterogyrus) is supported by the widened bridge between the dorsal and ventral ocular subunits, the reduced size and dorsal shift of the dorsal eye, its distinct separation from the anterior pronotal margin, the detachment of the lateral frontal ridge from the supraocular bead, the almost completely reduced setation of the antennal flagellum, and a one-segmented galea. The steep frontal side of the head, a transverse regular field of setae on the frontal region, and the fused laminatentoria are autapomorphies of Spanglerogyrus Folkerts, 1979. A field of sensilla on the interocular antennal groove is a potential cephalic autapomorphy of Heterogyrus. The cephalic characters we analysed remain ambiguous about the interrelationships among the three tribes currently recognized in Gyrininae.

A new species of Sonotetranychus (Acariformes: Tetranychidae) from China

The genus Sonotetranychus Tuttle, Baker & Abbatiello is recorded from mainland China for the first time. Sonotetranychus neosalicis sp. nov. is described from females collected on the leaves of Salix chaenomeloides Kimura (Salicaceae) in Nanchang, Jiangxi, China. This new species can be distinguished from other members of Sonotetranychus by femora I–IV with 8-6-3-2 tactile setae, genu III with three tactile setae, tibiae III–IV with 5-5 tactile setae and transverse striae between dorsal setae e. The key to Sonotetranychus species of the world is updated.

Life history of Chrysozephyrus alienus (Koiwaya & Monastyrskii, 2010) (Lepidoptera) in central Vietnam

We have successfully reared the larvae of Chrysozephyrus alienus (Koiwaya & Monastyrskii, 2010), and presented the life history of this species. The larval foodplant was found to be Lyonia ovalifolia var. pubescens. The tactile setae of the 1st instar larvae are absent at dorsal anterior area at the 1st abdominal segment and dorsal area at the 7th abdominal segment. The pattern is rather similar to that of Chrysozephyrus scintillans. Citation: Hasegawa T., Saito K., Vu Van Lien, Miyagawa T., Kubota A., Yokochi T., 2017. Life history of Chrysozephyrus alienus (Koiwaya & Monastyrskii, 2010) (Lepidoptera) in central Vietnam. Tap chi Sinh hoc, 39(3): 291-295. DOI: 10.15625/0866-7160/v39n3.9348. *Corresponding author: airsjapan64@gmail.com Received 20 March 2017, accepted 20 August 2017

Ontogenetic development and redescription of Eotetranychus xuzhouensis (Wang and Ma 1987) comb. nov. (Acari: Tetranychidae)

Platytetranychus xuzhouensis Wang and Ma 1987 is redescribed and combined as Eotetranychus xuzhouensis (Wang and Ma) comb. nov. based on the protonymph, deutonymph, male and holotype female specimens from En-Pei Ma’s collections. Eotetranychus xuzhouensis (Wang and Ma) comb. nov. can be distinguished from other members of Eotetranychus by the distinct shape of the aedeagus and tarsus I with one tactile seta proximal to duplex setae. The ontogenetic changes in leg chaetotaxy in Eotetranychus xuzhouensis (Wang and Ma) comb. nov. are given and discussed. Additional trends and reductive chaetotaxy of the leg segments suggest that Eotetranychus xuzhouensis (Wang and Ma) comb. nov. has its own basic larval-protonymphal pattern of setal additions.

A review of the taxonomy and biology of pseudoscorpions ofNannowithiusandTermitowithius(Pseudoscorpiones, Withiidae), inquilines of social insects

The Nannowithius group of the pseudoscorpion family Withiidae is newly defined, consisting of Nannowithius Beier, 1932 from northern Africa and the Middle East, and Termitowithius Muchmore, 1990 from east Africa. The group is characterized by the lack of a tactile seta on the posterior tarsi, and they are the only withiids to possess this character state. Both genera are associated as inquilines with social insects, Nannowithius with ants and Termitowithius with termites. Withius caecus Beier, 1929 and Plesiowithius dekeyseri Vachon, 1954 are redescribed and transferred to the genus Nannowithius, forming the new combinations N. caecus (Beier) and N. dekeyseri (Vachon). Plesiowithius is treated as a new synonym of Nannowithius. A revised description and new illustrations of Termitowithius kistneri Muchmore, 1990 are presented.

PM 7/116 (1)Tetranychus evansi

PM 7/116 (1)<i>Tetranychus evansi</i>

Early leaf miners and the ground plan of the lepidopteran larval trunk: Caterpillar morphology of the basal mothsHeterobathmia,Eriocrania, andAcanthopteroctetes

The larval trunk morphology including chaetotaxy, locomotory structures, and trunk musculature of Heterobathmia pseuderiocrania, Eriocrania cicatricella, and Acanthopteroctetes unifascia is described using conventional light, polarization, and scanning electron microscopy. The ground plan morphology of the lepidopteran larva and neolepidopteran caterpillar is discussed in light of the life history succession from free soil dwelling organism to endophagous and finally to a primarily free living, angiosperm associated organism. I suggest that the larval morphology is argued to be strongly influenced by the shift in number of surfaces present in the larval environment. Especially the environment of the endophagous species, where the upper surface of the leaf mine is linked to the presence of dorsal locomotory structures such as the retractable calli and dorsal friction patches is proposed to have had a significant impact on the morphology and locomotory mechnism of the lepidopteran caterpillar. The chaetotaxy of the lepidopteran ground plan is found to be simple, consisting only of primary and secondary tactile setae and segmental proprioceptors. The presumption of Gerasimov ([1935] Zool Anz 112:177-194) that MXD1 of the prothorax is a shifted mesothoracic MD setae is supported. I suggest that the serial arrangement of the proprioceptors MD1, present on all trunk segments except the prothorax, and a trisetous MV group on all the thoracic segments is part of the lepidopteran larval ground plan. The absence of apodeme structures associated with trunk musculature in the nonglossatans suggests that this is an autapomorphic character of the Lepidoptera and it is further found to have been influential in the evolution of the typical caterpillar trunk. The attachments of the thoracic muscles directly to the trunk integument, suggest that the apodemal structures ancestral to the Amphiesmenoptera have been reduced in the Lepidoptera. Within the non-Neolepidoptera, the lifehistory shift may have resulted in reduction of the dorsal locomotory structures, such as calli. The abdominal musculature and structural similarities further suggest that the ventral calli are structural predecessors to the crotchet bearing proleg of the "typical caterpillar."

A New Genus and Species of Chernetid Pseudoscorpion (Pseudoscorpiones: Chernetidae) from Hainan Island, China

Sinochernes wuzhiensis gen. n., sp. n., belonging to the family Chernetidae Menge, 1855, is described on the basis of sixteen specimens collected from tropical forest leaf litter in Wuzhi Mountain, Hainan Island, China. The genus is characterized by the presence of only 4 setae on cheliceral hand and of 3 blades in rallum, by the spermathecae having 2 thin tubes, by the presence of a tactile seta on tarsus IV and by the trichobothrial pattern. Detailed diagnosis, descriptions and illustrations are presented in this paper.

Larval morphology of Central European species of genus Stephensia Stainton, 1858 (Lepidoptera, Elachistidae)

The morphology of last instar larvae of Stephensia abbreviatella and Stephensia brunnichella is described and illustrated in detail. The study is based mainly on chaetotaxy of head capsule, as well as thoracic and abdominal segments. Head chaetotaxy of representatives of the family Elachistidae s.s., and chaetotaxy of Stephensia brunnichella are published for the first time. The larvae of studied species may be differentiated mainly by their size and differences in arrangement and length of some setae. The Stephensia larvae are characterized by some rare in the family but most likely plesiomorphic traits, e.g. by comparatively long tactile setae, trisetose L group on AI–VIII, as well as a set of seven tactile setae (D1–2, SD1, L1, L3, SV1, V1) and two proprioceptors (MD1, MV3) on AIX. A few larval characters of potential phylogenetic importance are discussed. The size reduction of the ventral prothoracic shield is supposed to be a potential autapomorphy for the genus Stephensia. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

10.1007/s11474-008-1014-0

An illustrated description of Pionacercus norvegicus larva is given and the female and male of this species are described for first time. Larvae of P. norvegicus differ from larvae of P. colymicus, P. anadyrensis, P. tundrosum, and P. major in the structure of the pedipalpal tarsus with especially long tactile setae (the length of these setae is equal to the entire length of all the pedipalpal segments). In other species studied, pedipalpal tarsus lacks such long setae (the longest setae are shorter than half length of all pedipalpal segments combined).

On the systematic position of the family Gyrinidae (Coleoptera: Adephaga)

Various characters of adult and larval members of Adephaga and Cupedidae were analyzed, and suggest that Gyrinidae are the sister-group of the remaining Adephaga, and are not closely related to the remaining aquatic Adephaga. The aquatic families Noteridae, Amphizoidae, Hygrobiidae and Dytiscidae seem to form a well founded monophyletic unit. The following characters are considered as synapomorphies of Adephaga excluding Gyrinidae: bifurcate condition of the muscle (= M.) tentoriopraementalis inferior, reduction of hypopharynx, strongly developed prosternal process, reduction in size and specialized modification of the ventral sclerite of the mesothorax, strongly developed mesofurcal arms, a high mesopleural ridge, globular mesocoxae restricted to rotatory movements, invaginated sternum VIII (coxostemum), the strongly curved base of the median lobe of the aedeagus, which articulates with the parameres, the rotated position of the aedeagus in repose, fusion of the larval clypeolabrum with the frons and reduction of the larval lacinia. Mesal shifting of M. episterno-coxalis prothoracis, and the fusion of the apical portions of the malpighian tubules of either side are considered as synapomorphies of Adephaga excluding Rhysodidae and Gyrinidae. Lateral reduction of the meta “sternal” transverse ridge and the presence of the subcubital setal binding patch of the hind wing are considered as synapomorphic characters of Trachypachidae, Noteridae, Amphizoidae, Hygrobiidae and Dytiscidae. We postulate that the metacoxal fusion occurred independently in gyrmids and the common ancestor of Trachypachidae, Noteridae, Amphizoidae, Hygrobiidae and Dytiscidae. Consequently we consider this character state as another synapomorphy of Trachypachidae and Hydradephaga excluding Haliplidae and Gyrinidae. The following characters are considered as synapomorphies of Noteridae, Amphizoidae, Hygrobiidae and Dytiscidae: Loss of tactile setae on the head capsule, metafurcal origin on the intercoxal wall, expansion of the intercoxal wall, elongation of the subcubital setal binding patch, loss of Mm. furca-coxale anterior and posterior, reduction of the larval abdominal segments IX and X, and the shifting of the uropmphi onto the ventral side of segment VIII. Presence of M. tentorio-mandibularis and M. stipitopalpalis intemus are certainly primitive features of adult gyrinids but the distribution of these character states among most members of Adephaga is yet unclear. Chemical defence gland constituents point towards a very isolated position of Gyrinidae. The old age of the group, documented by a larva found in upper Permian deposits, may support the hypothesis of a sister-group relation-ship between Gyrinidae and the remainder of Adephaga.

Cheliferoid pseudoscorpions (Arachnida, Chelonethi) from the Lower Cretaceous of France

Three pseudoscorpion fossils are reported from the Lower Cretaceous (uppermost Albian) amber of Archingeay (Charente-Maritime, France). These are the oldest described members of the Cheliferoidea Risso, 1826 and the first fossil pseudoscorpions to be described from France. Heurtaultia rossiorum n. gen., n. sp. is described from two incomplete adults. The new genus is characterized by having gaping chelal fingers, elongate tarsal setae on leg I (probably sexually dimorphic characters limited to male) and the basal position of the tactile seta on the tarsus of legs III and IV. The systematic position of Heurtaultia n. gen is uncertain, but it is provisionally assigned to the extant family Cheliferidae Risso, 1826. The third fossil is complete and probably represents a tritonymph of a different species of Cheliferidae, but it is not named. This specimen is partly enclosed in a layer of silk, which is interpreted as a moulting nest.

Wormholes, sensory nets and hypertrophied tactile setae: the extraordinary defence strategies of Brenthia caterpillars

Metalmark moth larvae in the genus Brenthia (Lepidoptera: Choreutidae) live beneath gauzy web shelters spun over a leaf surface and chew an escape hole into the floor of their nests through which they dart when alarmed. We provide a video and data showing that these larvae, when their webs are disturbed, shoot through their wormhole to the opposite side of the leaf at extremely high speeds: the fastest caterpillar passed through to the opposite leaf surface in only 100 ms. Experimental data show that Brenthia larvae use their silken web shelters as an extension of their sensory system. Although such usage of webbing is not surprising given what is known about spider webs, this is the first time such a behaviour has been shown to occur in Lepidoptera. Two grossly hypertrophied abdominal setae, directed behind the body, are not pulled through the wormhole, but instead remain intercalated into the silken lattice of the web shelter. By leaving the two setae engaged, the caterpillar is able to monitor both sides of its host leaf simultaneously. We report analogous escape hole behaviours in four other microlepidopteran families: Elachistidae, Gelechiidae, Oecophoridae and Pyralidae. In at least one genus of the latter family ( Monoloxis ), two caudally directed abdominal setae are hypertrophied in the same fashion as in Brenthia . We suspect that both escape holes and hypertrophied abdominal setae are more common and taxonomically widespread than presently recognized and that both ‘strategies’ will be shown to occur among other microlepidopterans.