Presence Of Eyespots Research Articles

A New Species of Acoela Possessing a Middorsal Appendage with a Possible Sensory Function.

Acoels, belonging to Xenacoelomorpha, are small worms with a relatively simple body plan and are considered a critical clade for understanding the evolution of bilaterians. Despite acoels' importance, however, many undiscovered species are predicted to be present worldwide. Here, we describe a new marine acoel species, Amphiscolops oni sp. nov., based on materials collected from the intertidal and subtidal zones of rocky shores at several localities along the Japanese Pacific coast. The new species is approximately 3 mm long and shows typical characteristics of the family Convolutidae, such as the presence of eyespots, symbiosis with algae, position of the gonopores, morphology of the bursal nozzles, lack of central singlet microtubules in the axonemes of spermatozoa, and funnel-like posture of the anterior end. Based on morphology and the results of molecular phylogenetic analyses, we assign this species to the genus Amphiscolops. Interestingly, these worms show unique behaviors such as swimming by flapping the lateral sides and actively capturing prey by swinging the anterior funnel. Furthermore, they possess a dorsal appendage-a characteristic previously unreported in Xenacoelomorpha-representing an evolutionary novelty acquired by this species.

Body size determines eyespot size and presence in coral reef fishes.

Numerous organisms display conspicuous eyespots. These eye‐like patterns have been shown to effectively reduce predation by either deflecting strikes away from nonvital organs or by intimidating potential predators. While investigated extensively in terrestrial systems, determining what factors shape eyespot form in colorful coral reef fishes remains less well known. Using a broadscale approach we ask: How does the size of the eyespot relate to the actual eye, and at what size during ontogeny are eyespots acquired or lost? We utilized publicly available images to generate a dataset of 167 eyespot‐bearing reef fish species. We measured multiple features relating to the size of the fish, its eye, and the size of its eyespot. In reef fishes, the area of the eyespot closely matches that of the real eye; however, the eyespots “pupil” is nearly four times larger than the real pupil. Eyespots appear at about 20 mm standard length. However, there is a marked decrease in the presence of eyespots in fishes above 48 mm standard length; a size which is tightly correlated with significant decreases in documented mortality rates. Above 75–85 mm, the cost of eyespots appears to outweigh their benefit. Our results identify a “size window” for eyespots in coral reef fishes, which suggests that eyespot use is strictly body size‐dependent within this group.

Diversity of Empruthotrema Johnston and Tiegs, 1992 parasitizing batoids (Chondrichthyes: Rajiformes and Myliobatiformes) from the Southwest Atlantic Ocean, with description of three new species.

During an extensive research project involving 519 specimens of batoids, including 13 species of Rajiformes and Myliobatiformes (Chondrichthyes) from the Argentine Sea, three new species of Empruthotrema were found and are described using morphologic characteristics and two molecular markers: LSU rDNA and COI mtDNA. The new species can be distinguished from their congeners by the number and distribution of the marginal loculi, the length and morphology of male copulatory organ, and the presence of eyespots. Additionally, multivariate analysis identified the dimensions of the pharynx and ejaculatory bulb as diagnostic features. Host specificity and previous records of the genus in the region are discussed. This is the first description of new species in this genus for the Southwestern Atlantic Ocean, as well as for arhynchobatid hosts.

The genus Loimia Malmgren, 1866 (Annelida: Terebellidae) off the Brazilian coast, with description of three new species and notes on some morphological characters of the genus.

Three new species of Loimia were collected along the Brazilian coast, during some independent projects, from shallow to deep waters off the continental slope. These species are L. megaoculata sp. nov., L. armata sp. nov., and L. brasiliensis sp. nov., all herein described and compared with the morphologically most similar congeners. Loimia megaoculata sp. nov., is characterized by having large, dark eyespots, progressively smaller from dorso-laterally towards lateral basal part of prostomium; lobes of segment 1 are distally rounded, roughly circular, barely reaching mid-length of upper lip; uncini have up to 6-7 teeth, including basal-most tooth. Loimia armata sp. nov., lacks eyespots; stout lobes of segment 1 nearly reach level of upper lip; uncini have up to 7-8 teeth, including basal-most tooth. Loimia brasiliensis sp. nov., has two narrow rows of eyespots; lobes of segment 1 are thin, reaching mid-length of upper lip; uncini have 5-6 teeth, including basal-most tooth. We provide a brief discussion on the main morphological characters useful for the taxonomy of this genus, such as presence of eyespots, and morphology of lobes of segments 1 and 3, of mid-ventral pads and neurochaetae. Up to now only two species had been recorded from Brazil, namely L. grubei and L. medusa, both doubtful records, as discussed along this paper.

Incidence of eyespot on winter triticale and quantification of Oculimacula spp. population using real-time PCR in Lithuania

The aim of this study was to estimate the incidence of eyespot in winter triticale crops in different agro-ecological zones of Lithuania and to use real-time polymerase chain reaction (Real-time PCR) to determine the dominant Oculimacula fungi populations in winter triticale crops grown in Lithuania, which has not been previously established. Differences in common fungicide usage practices in triticale crops between Lithuanian agro-ecological zones suggest that the composition of Oculimacula fungi differs across the country. From 2008 to 2012, a total of 70 winter triticale fields were reviewed for eyespot incidence, and the presence of eyespot was identified in 93.5% of the fields tested. Over this five-year period, the disease incidence averaged 32%. The highest incidence (34.8%) of eyespot was found in the Middle Lowland zone of Lithuania, the lowest (25.8%) was in the Eastern zone and an intermediate incidence (30.2%) was observed in the Western zone. During the 2010–2012 period, Oculimacula acuformis was the most prevalent Oculimacula spp. in the majority of triticale crops inspected. Only in 3 cases out of 27 was the amount of Oculimacula yallundae DNA higher than that of O. acuformis. According to our results, the incidence of eyespot in triticale varied greatly and could be of economic importance in some fields. The predominance of O. acuformis over O. yallundae is an important consideration in the choice of fungicides for eyespot control.

Description of the new heterotrophic dinoflagellate Stoeckeria changwonensis n. sp. from Korean coastal waters and emended description of the genus Stoeckeria and the type species Stoeckeria algicida

The planktonic heterotrophic dinoflagellate Stoeckeria changwonensis n. sp. isolated from the coastal waters off Korea is described from living and fixed cells by light, scanning electron (SEM), and transmission electron microscopy (TEM). For comparison with closely related species, the ultrastructure of Stoeckeria algicida, the only Stoeckeria species previously known, using TEM was also examined. Furthermore, DNA sequence data were collected from the small subunit (SSU), the D1–D3 large subunit (LSU), internal transcribed spacer regions (ITS1 and ITS2), and 5.8S of the ribosomal rDNA of S. changwonensis and compared to S. algicida. The SSU, ITS1-5.8S-ITS2, and the D1–D3 LSU rDNA sequences of the new dinoflagellate were ca. 2.2%, 16.8%, and 5.4% different, respectively, from those of S. algicida, but very similar to those of an unidentified dinoflagellate strain from Florida, USA, known as “Shepherd's Crook”. In the phylogenetic tree based on D1–D3 LSU rDNA sequences, S. changwonensis formed a clade with this unidentified strain, which was clearly divergent from a clade comprising S. algicida and another unidentified “Shepherd's Crook” strain. Morphological analysis showed that S. changwonensis had thin plates with a Kofoidian plate formula of Po, cp, X, 4′, 2a, 7″, PC, 6c, 5+s, 5‴, 0p, and 2″″, which conformed to the genus Stoeckeria. The size and overall shape of this dinoflagellate were similar to those of S. algicida. However, the size and position of each cingular plate relative to the surrounding plates in S. changwonensis were clearly different from those of S. algicida. The length of c2, c3, c4, c5, and c6 of S. changwonensis were similar, unlike in S. algicida, in which the lengths of c3 and c4 greatly exceeded that of c2, c5, and c6. In addition, plate c6 of S. changwonensis was sufficiently long to contact the 6″ plate, again in contrast with what happens in S. algicida. Using TEM, an eyespot in the sulcal areas of both Stoeckeria changwonensis and Stoeckeria algicida, which has not been seen in other species of the family Pfiesteriaceae was herein reported for the first time. On the basis of morphological and phylogenetic criteria, it is proposed that this is a new species of the genus Stoeckeria. In addition, the description of S. algicida has been emended to include previously unreported details regarding the relative size and position of the cingular plates, the presence of eyespots, and the ultrastructure of its cells examined using TEM.

Description of Neolepidapedoides subantarcticus sp. nov. (Digenea, Lepocreadiidae) from sub-Antarctic notothenioid fishes

AbstractNeolepidapedoides subantarcticus sp. nov. (Digenea, Lepocreadiidae) is reported from the intestine, mainly the jejunum, of fishes in the eastern mouth of the Beagle Channel and in the harbour of Ushuaia in the Beagle Channel (Tierra del Fuego, Argentina) at a depth 7–30 m. The typical host is Patagonotothen longipes, other hosts are P. tessellata, P. brevicauda and Champsocephalus esox. The male terminal genitalia indicates that the new species belongs to the genus Neolepidapedoides (Lepocreadiidae, Lepocreadiinae). The most important taxonomic features are the presence of eye-spots, the spined tegument, the “Opechona-type” cirrus-sac, the external seminal vesicle free in the parenchyma, the gonads arranged in tandem, the vitelline follicles extending from the level of the oesophagus in the forebody to the posterior end of the body and an I-shaped excretory vesicle reaching to the intestinal bifurcation and the absence of a pseudoesophagus. Ten previously described species differ from the N. subantarcticus sp. nov. mainly in the extent of the vitelline fields and length of the excretory vesicle which reaches into forebody.

Tardigrades of Israel with description of four new species

Only few species of tardigrades have been recorded from Israel. In this paper we report an additional 20 species, 18 of which are new records for that geographical area; four (Bryodelphax meronensis sp. nov., Macrobiotus dimentmani sp. nov., Pseudobiotus hirsutellus sp. nov. and Mixibius schnurae sp. nov.) are new to science. Bryodelphax meronensis sp. nov. differs from similar species (B. alzirae, B. tatrensis and B. mateusi) in details of the cuticular ornamentation and the absence of papilla on the hind legs. It also differs from B. alzirae by the presence of 12 lateral intersegmental platelets, instead of 6. It differs from B. atlantis in details of the plate ornamentation, lack of eyes, and shorter internal buccal cirri. Macrobiotus dimentmani sp. nov. differs from M. diffusus with more slender claws, the external claws slightly longer, and in characteristics of the eggs (the apical portion of the conical processes is subdivided into two to six long, flexible terminal points that are not very thin filaments; each process has a ring of basal dots, the egg shell has an obvious granulation). Mixibius schnurae sp. nov. differs from all other known species within the genus by characteristics of the cuticular ornamentation; in addition it differs from M. ornatus and M. sutirae in having the stylet supports inserted on the buccal tube in a more cephalic position; and from M. ninguidus in having longer buccal tube and shorter second placoid. Pseudobiotus hirsutellus sp. nov. differs from P. vladimiri in the presence of eye spots; cuticular spine-shaped processes present on the central portion of the body as well as the anterior and posterior portions; wider buccal tube, longer placoids; longer claws that are without accessory points; and the absence of oval papillae on the first three pairs of legs. The new species differs from P. spinifer in having less numerous and smaller spine-shaped cuticular processes; wider buccal tube; longer placoids; and the absence of oval papilla on the first three pairs of legs.

A New Species of Empruthotrema (Monogenea: Monocotylidae) from Pteromylaeus bovinus (Myliobatidae) from the Western Mediterranean

Empruthotrema chisholmae n. sp. is described from specimens recovered from a bull ray Pteromylaeus bovinus (Geoffroy Saint-Hilaire, 1817) at the Oceanogràfic Aquarium in Valencia, Spain. The bull ray was caught in the Spanish Mediterranean (Puerto de Mazarrón, Murcia). The new species resembles 4 others of the same genus ( Empruthotrema dasyatidis Whittington and Kearn, 1992, Empruthotrema kearni Whittington, 1990, Empruthotrema stenophallus Chisholm and Whittington, 2005, and Empruthotrema tasmaniensis Chisholm and Whittington, 1999) in having a haptor with 13 marginal loculi, the posteriormost loculus single and medial. The new species can be distinguished from these other species of the genus by the morphology of the sclerotized male copulatory organ, which is the shortest described. The new species also differs from the other species by the following combination of features: haptor with 13 marginal loculi, the presence of eyespots, the absence of an accessory piece associated with the male copulatory organ, and a long egg appendage (more than 150 µm). Empruthotrema chisholmae is the first species of the genus reported from the Mediterranean.

The perceptual effect of eyespots: Or the devil may seem closer than she really is

The effect of eyespots and their positioning on adults' judgments of the perceived headings of depicted creatures was examined. Ninety-three adults saw 78 drawings comprising six sets, with each set consisting of one eyeless, eight monocular and four binocular creatures. Results indicated that judgments of the perceived direction of the creatures' travel were affected by the presence of eyespots. The effect was such that eyed stimuli veered towards the observer. This effect was, however, dependent on eyespot location, being strongest for monocular creatures when eyespots were on the lower parts of the depicted heads. For binocular creatures it was stronger when the eyes were on the horizontal line than when they were on the vertical line. Responses were also dependent upon the type of depicted creature. The implications of these results for understanding perception of pictures are discussed.

Significance of butterfly eyespots as an anti‐predator device in ground‐based and aerial attacks

Many butterfly genera are characterised by the presence of marginal eyespots on their wings. One hypothesis to account for an occurrence of eyespots is that these wing pattern elements are partly the outcome of visual selection by predators. Bicyclus anynana (Satyrinae) has underside spotting on its wings but there is also a seasonal form in which the eyespots are reduced in size or totally absent. This natural variation gives us a useful tool to test the hypothesis that marginal eyespot patterns can decoy the attacking predator by, at least sometimes, diverting attack from vital body parts to the edges of the wings. We used lizards, Anolis carolinensis, and pied flycatchers, Ficedula hypoleuca, as predators for living spotted and spotless B. anynana. The presence of eyespots did not increase the escape probability of resting butterflies once captured (even a form with enlarged eyespots did not add to effective deflection of attacks). There was also no evidence that eyespots influenced the location of strikes by the predators. This study thus provides no support that marginal eyespot patterns can act as an effective deflection mechanism to avoid lizard or avian predation.

Disease severity and yield of pure‐line wheat cultivars and mixtures in the presence of eyespot, yellow rust, and their combination

Five winter wheat cultivars, six two‐component cultivar mixtures, and one four‐way mixture were grown in the presence of yellow rust, eyespot, both diseases, and neither disease for three seasons. On average, mixtures reduced the severity of yellow rust relative to their component pure stands by 53%. The four‐component mixture provided better yellow rust control than did the two‐way mixtures. Eyespot severity was reduced through mixing only in the absence of yellow rust and by only three of the seven mixtures (mean reduction = 13%). Yellow rust was 13% less severe in the presence of eyespot, and eyespot was 10% more severe in the presence of yellow rust. Averaged over all years, the mixtures increased yield relative to the pure stands by 6·2, 1·7, 7·1, and 1·3% in the presence of yellow rust, eyespot, both diseases, and neither disease, respectively. Two mixtures provided significant yield increases over the means of their component pure stands (7% and 9%) in the presence of eyespot even though one of them did not significantly reduce eyespot severity. Accounting for all disease treatments and years, four mixtures provided distinctly higher yield increases than the other three. In mixtures containing a resistant cultivar and a cultivar susceptible to eyespot, yield loss by the susceptible cultivar was not compensated for by increased yield of the resistant cultivar. The mixtures showed improved yield stability relative to the pure stands, with the four‐component mixture being particularly stable.

Mycteronastes undulatae gen. nov., sp. nov. (Monogenea: Monocotylidae) from the nasal cavities of Raja undulata in the eastern Atlantic

Mycteronastes undulatae gen. nov., sp. nov. (Monogenea: Monocotylidae) is described from the nasal cavities of Raja undulata caught off Arcachon in France and off Lisbon (Tagus estuary) and Sines in Portugal. Merizocotyle icopae Beverley-Burton & Williams, 1989, be-comes Mycteronastes icopae n. comb., the type species of Mycteronastes gen. nov. Similarities between M. icopae and M. undulatae include the arrangement of the haptor loculi and hooks, the general disposition of the reproductive system, the presence of eyespots and the habitat (the nasal cavities of the host). However, a distinctive feature is the absence of a copulatory sclerite and bulb in M. undulatae. The diagnoses of the following taxa are amended: Monocotylidae, Merizocotylinae and Merizocotyle.

Studies on Monogenetic Trematodes. XXV. Six New Species of Ancyrocephalinae from the Gills of Zanclus canescens (Linnaeus) with a Key to the Genera of Ancyrocephalinae

Six new species of Ancyrocephalinae, namely, Hamatopeduncularia heraldi, Parahaliotrema dempsteri, P. parahaliotrema, Pseudohaliotrema brevis, P. canescens, and P. zanclus are described from the gills of the Moorish Idol, Zanclus canescens (Linnaeus). Parahaliotrema is proposed as a new genus. It differs from the nearest related genera: (1) Haliotrema by the presence of eyespots, confluent intestinal crura, and a dextral instead of a dextroventral vagina; (2) Metahaliotrema by the presence of a vagina, and (3) Pseudohaliotrema by the presence of eyespots.

The Germinal Development in the Daughter Rediae of an Ophthalmo-Xiphidiocercaria from Pomatiopsis lapidaria

ALLOCREADIIDAE. In fact, recent work indicates that this family should include only species with ophthalmo-xiphidiocercariae (Hopkins, 1934; Cable and Hunninen, 1942). The structure of cercariae of this type, especially the presence of a stylet and stylet glands, suggests that this family is related to the PLAGIORCHIOIDEA. We might go even further and suggest the hypothesis that this group on account of the presence of eye-spots in the cercariae and their development in rediae is more primitive than the PLAGIORCHIOIDEA, and may be close to the ancestral type from which the true plagiorchiids developed. This possibility made it of special interest to determine whether the germinal development in the daughter rediae of Cercaria pomatiopsidis showed any resemblance to that in the daughter sporocysts of the plagiorchiids. During the summer of 1948 we had the opportunity of examining 1282 specimens of Pomatiopsis lapidaria collected near Ann Arbor, Michigan, of which 37 or about 3.0 per cent were infected with C. pomatiopsidis. Most of the infections were mature or old but a few immature daughter rediae were available for study.