The anatomy and attachment mechanism of the haptor of a Capsala sp. (Platyhelminthes: Monogenea: Capsalidae) on the blue marlin,Makaira nigricans (Istiophoridae)

The muscular anatomy and fine structure of the haptor of a monogenean, Capsala sp., together with an observational distribution study, are described from specimens collected from the dorsolateral and ventral surfaces of the blue marlin, Makaira nigricans. The haptor is composed of seven loculi, which are arranged around a central pair of accessory sclerites. Marginal hooklets and hamuli were not observed. The presence of an outline left by the haptor on the host's skin and the lack of evidence of an adhesive secretion suggested that the haptor attaches primarily by suction. Tendons originating in the extrinsic peduncle muscles insert, via a proximal notch in the accessory sclerites, into the basal tegumental lamina on the ventral surface of the haptor. On contraction the centre of the haptor is thought to be drawn upwards both directly by the extrinsic tendons in the haptoral wall but also by the accessory sclerites which are brought into a vertical position. This increases the volume beneath the haptor, consequently reducing the pressure and thus producing suction. The ribbed marginal valve prevents the inward movement of water. Intrinsic circular and radial muscles in the haptoral wall are also thought to produce suction by drawing the haptoral wall inwards, again increasing the volume beneath and causing a pressure reduction. It is suggested that interconnecting fibres observed between the intrinsic muscles may store elastic energy, allowing Capsala sp. to maintain suction attachment without having constantly to contract its muscles. Papillae on the inner ( = ventral) surface of the haptor are suggested to aid attachment by firstly spreading the negative pressure over the inner surface of the haptor and, secondly, through resisting the shear forces encountered as the fish swims. Both functions are achieved by increasing the surface area of contact with the host's skin, and therefore the frictional forces. Theoretical estimates of the suction efficiency indicate that suction is double the maximum theoretical drag forces which would be experienced by Capsala sp. when M. nigricans is swimming at speeds of both 1 and 20 m s^?1 and suggests that suctorial attachment is efficient. The distribution of Capsala sp. is not thought to be restricted by the surface topography of the host, demonstrated by the fact that individuals were located in both the roughest and smoothest areas of the marlin's skin surface. Distribution is therefore thought to be influenced by other factors such as hydrodynamics, nutritional value of the attachment site, immunological restrictions or cross‐fertilization between parasites.     

Pre-ovipositional and ovipositional behaviour of Lasioseius ometes (Oudemans) and Hypoaspis kargi Costa (Acari: Dermanyssiae: Ascidae,Laelapidae) with notes on egg protection strategies in Mesostigmata

Egg deposition by the soil mites Lasioseius ometes (Oudemans, 1903) and Hypoaspis kargi Costa, 1968 was observed using continuous video-monitoring. The process in both species was found to consist of four distinct phases. In Phase 1, both species engage in pre-ovipositional activity prior to the egg being extruded from the genital opening. In L. ometes, the female often selects a substrate depression for egg laying and examines the depression carefully with the gnathosoma and legs I before oviposition. In H. kargi, egg deposition sites are chosen without regard for substrate depressions. Phase 1 lasted approximately 3 minutes for both species. Phase 2 involved egg extrusion and holding of the egg beneath the gnathosoma. Phase 2 lasted approximately 20 times longer in L. ometes (5 minutes) than in H. kargi. Alteration of the egg surface in the form of thorn-like outgrowths was recorded in L. ometes. Egg deposition occurs in Phase 3, and in L. ometes the egg is generally placed at the deposition site using the chelicerae. Hypoaspis kargi also uses the chelicerae for egg manipulation, but also adjusts orientation of the egg with legs I. The sticky nature of egg surface in H. kargi may provide a means for the female to effectively cover the exposed egg with a protective layer of soil particles. Egg deposition in both species occurred in less than 90 seconds. Phase 4 involves egg covering, but behaviour of the female during this last phase differs markedly between the two species. In L. ometes, the female tends to remain close to the egg, whereas in H. kargi the female moves away from the egg to search for substrate particles appropriate for its covering. The average time for Phase 4 in H. kargi was approximately four times longer (80+ minutes) than in L. ometes.     

Morphology of tube-like threads related to Limnochares aquatica (L., 1758) (Acariformes: Hydrachnidia: Limnocharidae) in the laboratory

Water mites Limnochares aquatica (L., 1758) during maintenance in the laboratory for a long period of time in constant conditions periodically produced certain whitish flocculent material consisting of long rigid unbranched tube-like threads 1.3 ± 0.3 µm in diameter crossing freely. These threads were studied using light-optical as well as transmission electron microscopical and scanning electron microscopical methods. Microbiological staining was also applied to the threads to exclude their bacterial or fungal origin. The thread wall is built of fine fibrils arranged at different angles to the long axis of threads that is reflected in a certain stratification of the wall. Threads are mostly hollow or may contain electron-dense homogeneous material. No cell components are present in the thread composition. Numerous dermal glands with their small slit-like orifice scattered throughout the mite body surface are thought to produce these threads. Most probably the thread formation is a reaction of mites to stress under laboratory conditions, and this is expected to be a type of defensive reaction.     

Revision of the spider genus Ischnocolus Ausserer, 1871 (Mygalomorphae: Theraphosidae: Ischnocolinae)

The genus Ischnocolus is redefined based on type material, and extra specimens. Representatives of the genus are distinguished by clavate tarsal trichobothria arranged in median apical row; by the maxillae with lighter colour on prolateral edge. Males of the genus Ischnocolus Ausserer are recognized by the cheliceral intumescence, sigmoid ventral furrow on palpal tibia, unequal cymbium lobes, tibial apophysis absent, great number of spines on ventral side of tibia I, and male superior tarsal claws bipectinate. Species included are: Ischnocolus valentinus (Dufour) [= I. holosericeus L. Koch, I. triangulifer Ausserer, I. algericus Thorell, I. fuscostriatus Simon, I. maroccanus (Simon), I. mogadorensis (Simon), I. numidus Simon, I. tripolitanus Caporiacco, Avicularia andalusiaca Simon], Ischnocolus hancocki Smith, Ischnocolus jickelii L. Koch (senior-synonym of Chaetopelma adenense Simon) and Ischnocolus ignoratus sp. nov. Ischnocolus tomentosus Thorell is considered incertae sedis. The following species are considered species inquirenda: I. tunetanus Pavesi and I. fasciculatus Strand. http://www.zoobank.org/urn:lsid:zoobank.org:pub:207143F4-A235-4411-96D4-D4787ABF271F     

Another migid in the wall: natural history of the endemic and rare spider Calathotarsus simoni (Mygalomorphae: Migidae) from a hill slope in central Argentina

A population of Calathotarsus simoni Schiapelli and Gerschman (1975) was discovered on a hillside in the Ventania system, Argentina. Our objectives were to quantify burrow density, record burrow morphology and door characteristics and describe the micro-habitat. We counted 57 burrows and report a density of 0.01 burrows/m². Aggregation indices suggest that burrows are aggregated under some area plots but more evenly distributed on others. The trapdoor is thick and rigid with bevelled edges connected to the entrance rim by a narrow articulated hinge. Two egg sacs from females were obtained and data on eggs and spiderlings are presented. We registered six burrows of an undetermined species of Actinopus. While a few specimens of Actinopus sp. were found inhabiting this hillside, the highest proportion of burrows belonged to C. simoni. Spider diversity on the hillside shows the predominance of Linyphiidae, Nemesiidae and Gnaphosidae. One juvenile of C. simoni was captured using pitfall traps.     

An overview of the mite fauna (Acari) associated with eumenine wasps (Hymenoptera: Vespidae) found in Brazilian collections

ABSTRACT

Mites can be associated with other organisms as parasites, commensals, phoretic, among others, such as some Winterschmidtiidae that present cooperative relationships with solitary wasps (Eumeninae). These wasps have one or more cavities in their body surface that are capable of carrying mites, called acarinaria. Studies carried out in the northern hemisphere suggest that these relationships are species-specific. However, in South America, there are few studies in this field. Aiming to recognize and increase our knowledge of the species of solitary wasps from Brazil that are associated with mites, we examined 61 wasps belonging to 29 species and four genera from Brazilian museum collections. All of the specimens studied presented at least one type of acarinarium in their bodies. There were mites in all specimens of wasps, but not all of them were associated with an acarinarium. The mites belong to 11 different genera: six in Winterschmidtiidae (possibly cooperation relationships); one in Oplitidae (phoresy); one in Erythraeidae (parasitism); two in Acaridae (phoresy); and one in Histiostomatidae (phoresy). Detrended correspondence analysis and indicator species analysis were conducted to test the preference of the mite genera for species of wasp and for site (regions of the wasp’s body). These tests were significant only for the mite genus Vespacarus preferring Parancistrocerus wasp species and the metasomal acarinaria. Some of the mites did not have a specific host, and some wasps carried more than one species of mite, differing from the specific interactions reported for the northern hemisphere.     

Systematics and ecology of the caecilian Crotaphatrema lamottei (Nussbaum) (Amphibia: Gymnophiona: Scolecomorphidae)

New observations on Crotaphatrema lamottei are reported based on fieldwork on Mount Oku between 2006 and 2008. This species was encountered by pitfall trapping and digging, but encounter rates were low. Six new specimens of C. lamottei add substantially to the previous hypodigm for the species and genus, and new morphometric and meristic data are presented. Analysis of mitochondrial DNA sequence data supports strongly the monophyly of Crotaphatrema. The genetic and morphological distance between C. lamottei and Crotaphatrema tchabalmbaboensis is small, although there is a clear difference in colour pattern. The Data Deficient IUCN conservation status of all three species of Crotaphatrema is likely to change most readily as a result of better data on distribution.     

Morphology and natural history of the cryptogenic sponge associate Polydora colonia Moore, 1907 (Polychaeta: Spionidae)

The polychaete Polydora colonia is a widely distributed symbiont of sponges that has been reported as introduced into the Mediterranean Sea. Polydora colonia is re-described based on specimens associated with the sponges Microciona prolifera and Halichondria bowerbanki from New York and aspects of its reproduction and feeding biology are described for the first time. The morphology of P. colonia agrees with previous reports of this species. Females of P. colonia deposited egg capsules (14–19 eggs/capsule) in their tubes on sponges and adelphophagy was observed. Larvae appear to be competent to settle on hosts at the 13-chaetiger stage. One commensal ciliate and one parasitic copepod were found associated with P. colonia. P. colonia as an introduced species is evaluated based on current evidence. Sponge material was observed in the gut of > 50% of the worms examined but further studies are needed to evaluate whether P. colonia is selectively feeding on M. prolifera.     

Association of a juvenile phoretic uropodid mite with the beach hopper Traskorchestia traskiana (Stimpson, 1857) (Crustacea: Talitridae)

A phoretic association of an undescribed uropodid deutonymph (Acari: Uropodidae) with the beach hopper Traskorchestia traskiana (Crustacea: Talitridae) is examined. Only juvenile mites (deutonymphs) were found attached to the coxal gills of the 257 beach hoppers examined. Both prevalence (range = 27·1–75·0%) and mean intensity (range = 1·3–3·7) increased as host size increased, possibly due to increased exposure time to the mites and a greater area for attachment in larger hosts. Among the gills, the mites exhibited a preference for coxal gill 5, which may be due to pH and humidity gradients but did not seem to be influenced by grooming or agitation of the gills by adjacent appendages.     

Rediscovery,natural history,and conservation status of Idiocranium russeli Parker, 1936 (Amphibia: Gymnophiona: Indotyphlidae)

The indotyphlid caecilian amphibian Idiocranium russeli Parker, 1936 is the only nominal species in its genus. Apart from two additional, largely overlooked locality records that we consider to be of an undescribed species, I. russeli is known with certainty from only a single collection of c.50 specimens from a single locality in 1933. We report new material from fieldwork in 2012 carried out in the vicinity of the type locality. Digging surveys at 34 sites for a total of >2000 person minutes found 50 I. russeli at 15 of these sites, extending the known range of the species by more than 40 km south and from an elevation of c.670 m to 104–820 m. The species probably occurs in nearby Nigeria and in some protected areas, is tolerant of some human disturbance, and is likely to move from Data Deficient to Least Concern on the IUCN Red List. Males have relatively longer and wider heads than females. Total length measured for preserved specimens is less than for freshly anaesthetized specimens, by up to 14.1%. Previously, preserved I. russeli were reported as having a maximum length of 114 mm, but the new sample includes specimens with total lengths of 145 mm in preservation and 167 mm when fresh. The sex of the smallest independent specimens (total length 62 mm in preservation) could be determined from examination of the gonads, hatchlings are c.30 mm, and I. russeli is confirmed as one of the smallest known caecilian species.     

New troglobitic species of the genus Troglocheles (Acari: Prostigmata: Rhagidiidae) from caves in northern Italy and Austria,with a key to adult species of the genus

Three new troglobitic species of rhagidiid mites of the genus Troglocheles – two from northern Italy, Troglocheles quinquesolenidiata sp. nov. and T. lanai sp. nov., and T. christiani sp. nov. from Austria – are described. A key to adults of the known species of the genus Troglocheles Zacharda of the world is given. In these vicariant species the different apomorphic morphological traits, troglomorphisms, are discussed in aspects of allopatric speciation, climatic relict hypothesis and evolutionary processes of adaptation to specific niches and time of occupation of the subterranean habitat. All new taxa are authored by M. Zacharda only.     

On the systematics,distribution and conservation status of Ichthyophis longicephalus Pillai, 1986 (Amphibia: Gymnophiona: Ichthyophiidae)

The caecilian Ichthyophis longicephalus was described in 1986 based on a single specimen. Only one specimen has been referred subsequently to this species, and the validity of that referral has been questioned. Seven specimens discovered in 2009–2010 at two new localities and two specimens collected in 1990 from a third locality are referred here to I. longicephalus. These specimens are described and compared with the poorly preserved holotype. Mitochondrial DNA data are consistent with the interpretation that the new specimens represent a single species distinct from (and most closely related to I. tricolor among) sampled congeners. The previously referred specimen, from c. 320 km south of the type locality, is not I. longicephalus and probably represents an undescribed species. The “rediscovery” of I. longicephalus in forests and disturbed habitats indicates that the species probably could be transferred from the Data Deficient to the Least Concern category of the IUCN Red List.     

Attachment site selection of Hydrachna and Eylais (Acari: Hydrachnellae) watermite larvae infecting Corixidae (Hemiptera: Heteroptera)

The sites of attachment of four larval watermite species were recorded from four corixid species in Lough Corrib, Ireland. Parasitic watermites exhibited preferences in respect of attachment sites on the corixid hosts and these patterns were consistent for all host species examined. Hydrachna cruenta utilized areas of the host which were in direct contact with the water, the distribution of larvae reflecting the general behaviour and microdistribution of the hosts. Hydrachna conjecta infected the ventral hemielytra with a significant asymmetrical distribution on the right hemielytron, resulting from the folding pattern of the hemielytra and the larval route of entry to the subhemielytral air space. Eylais species attached to the abdominal terga of the host, E. infundibulifera infecting the anterior two terga and E. discreta terga three and four. Cymatia bonsdorffi was not parasitized by E. infundibulifera and on this host the majority of E. discreta attached to the second abdominal tergite. Eylais species infecting small corixid hosts may avoid interference competition with H. conjecta by attaching to the left side of the abdomen. Attachment site selection may contribute towards alleviation of intraspecific and interspecific interference competition for larval growing space.     

Observations on mermithid parasitism (Nematoda: Mermithidae) in two species of Lasius ants (Hymenoptera: Formicidae)

The morphological effects of nematode parasitism by Pheromermis myrmecophila were investigated in two species of ants, Lasius flavus and Lasius niger, collected on Clare Island, Ireland. Infected males and queens were found for L. flavus but only infected queens in L. niger. The numbers of nematodes present in each infected specimen were counted and their lengths were measured. Head width, femur length and wing measurements were made for infected and non-infected individuals of both species. In queens, the length of the nematodes decreased as the number per ant increased. When single nematodes were present their mean lengths were significantly greater in L. flavus than in L. niger. In addition to the reduction in wing size for all parasitized specimens, head widths and femur lengths of the queens were significantly different in both species. A log–log graph of radial cell length versus width suggested a linear reduction of wing size.     

Necrophagous or predators? The role of Pheidole radoszkowskii Mayr (Hymenoptera: Formicidae) on Rattus norvegicus (Berkenhout) carcasses (Rodentia: Muridae)

This study aimed to identify the feeding habit of Pheidole radoszkowskii Mayr on Rattus norvegicus (Berkenhout) carcasses, as well as whether its presence limits the occurrence of flies. Pheidole radoszkowskii exhibited more necrophagous than predatory behaviour. Its abundance was inversely proportional to that of flies, confirming that this ant species may cause lesions in carcasses and its presence limits the occurrence of flies. This work clarifies the behaviour of an ant species often encountered on carcasses.     

Life history of Paraselenis (Spaethiechoma) dichroa (Germar, 1824) (Coleoptera: Chrysomelidae: Cassidinae) in natural conditions of Atlantic Forest from Brazil

Cassidinae Gyllenhaal? is the second largest subfamily of Chrysomelidae (Coleoptera), which presents characteristic morphology, biology and behaviour. The current study describes the life cycle of Paraselenis(Spaetiechoma) dichroa (Germar), ?determining biological and behavioural aspects as well as the action of natural enemies on populations, when the species has maternal care. The study was conducted between February and April 2015 in the National Forest of Passa Quatro, municipality of Passa Quatro, Minas Gerais state, Brazil. Daily observations were made (morning and afternoon) to evaluate the offspring of females on Ipomoea sp. and Merremia macrocalyx (O’Donell?) (Convolvulaceae), as well as the actions of natural enemies on the young. The eggs are deposited on the midrib and abaxial surface of leaves (n = 25). Egg clusters are pedunculated, arranged in groups and devoid of any cover. On average, each female produced 27.3 ± 5.6 (n = 16) eggs, with a mean incubation period of 12.7 ± 2.9 days (n = 10 females with their young). The larvae remained grouped in the leaves throughout development, except when they fed. They retained faeces and exuviae as a stacked faecal structure on their mobile urogomphi (caudal process) like a faecal shield. The mean number of larvae per female was 12.7 ± 10.1 (n = 19) and the larval period lasted 24.9 ± 4.5 days (n = 12). Pupation occurred on the stem of the plant (n = 16). On average there were 8.1 ± 8.5 individuals for pupae progeny (n = 14). The mean duration of the pupal stage was 10.4 ± 3.3 days (n = 5). Overall, 3% of adults emerged (n = 13 individuals), with a total cycle time of 41.3 ± 8.4 days (n = 6). Adults are sexually dimorphic in the elytral shape. Females remain with the offspring throughout development. The natural enemies of immatures were Emersonella pubipennis Hansson? (Hymenoptera: Eulophidae), Tachinidae (Diptera) and Stiretrus decastigmus (Herrich-Schaeffer?) (Heteroptera: Pentatomidae), Conura sp. Spinola? (Hymenoptera: Chalcididae) and Brachymeria sp. Westwood? (Hymenoptera: Chalcididae). The information presented here on the natural history of P. dichroa are important as they may serve as a starting point to understand evolutionary questions and multispecies interactions.     

Rhynchocoel vessel in Cephalotrichidae (Nemertea: Palaeonemertea)

The morphology of the rhynchocoel blood vessel was studied in 26 specimens representing 14 species of the family Cephalotrichidae. In eight specimens the vascular system could not be traced because of their small size, poor fixation, or contraction during fixation. In the other 18 specimens, a short mid-dorsal rhynchocoel vessel was found. In Cephalothrix adriatica, C. hongkongiensis, C. kefersteini, C. oestrymnica, C. orientalis, C. rufifrons, C. cf. fasciculus and C. cf. simula, the mid-dorsal rhynchocoel vessel penetrates the dorsal side of the proboscis insertion, and extends backward abutting the mid-dorsal rhynchocoel wall (Type A). In C. filiformis sensu Iwata (1954 Iwata, F. 1954. The fauna of Akkeshi Bay. XX. Nemertini in Hokkaido. J Fac Sci Hokkaido Univ Ser VI, Zool., 12: 1–39.  [Google Scholar]), the vessel is pendant in the rhynchocoel above the proboscis (Type B). In C. filiformis s.str., the vessel runs in the proboscis wall, after passing through the proboscis insertion (Type C). Morphology of the rhynchocoelic vessel might have taxonomic significance in cephalothrichids.     

An unusual Botanophila–Epichloë association in a population of orchardgrass (Dactylis glomerata) in Poland

Grass-infecting Epichloë fungi depend on flies of the genus Botanophila (Diptera: Anthomyiidae) for the transfer of spermatia (gametes) and fertilization. Flies lay eggs on fungal structures and their larvae use this as a source of food, hence, this interaction is generally considered to be obligatory and mutualistic. In the present study, we monitored the occurrence of Botanophila flies in a population of Epichloë-infected wild orchardgrass (Dactylis glomerata) in central Poland. The number of eggs per stroma ranged from 0 to 14. Overall, 24.83% of all examined stromata had no eggs or brood chambers, whereas the incidence of fertilized stromata ranged from 89.66% to 100% depending on the year. Nearly all stromata that exhibited no signs of fly visitation were fertilized. These results suggest that in the Polish population of D. glomerata, sexual reproduction of Epichloё fungi depends on spermatia-carrying vectors other than Botanophila.