Dorsal Papillae Research Articles

A morphological description of Onchidium reevesii (Gastropoda: Eupulmonata: Systellommatophora)

ABSTRACTThis morphological description of Onchidium reevesii (J.E. Gray, 1850), a common species on the coast of China, previously called Onchidium struma (Qiu, 1991), includes the external features and the digestive, nervous and reproductive systems. The radula and the penis are illustrated using electron microscopy. The surface of the notum is granular and hundreds of dorsal papillae are present, each with an eye. The position of the pneumostome is mid posterior on the hyponotum. The radular formula varies from 62:1:62 to 110:1:110. A convolute tubular rectal gland is present. Unusual features of the reproductive system include the penis having a proximal long, spiral stalk followed by a distal region covered with hooks, and the flagellum of the penial gland being long and heavily coiled.

Redescription of Leocrates chinensis Kinberg, 1866 (Annelida, Hesionidae).

Zhi Wang, Jian-Wen Qiu, and Sergio I. Salazar-Vallejo (2018) Leocrates chinensis Kinberg, 1866 is the type species of Leocrates Kinberg, 1866 (Annelida, Hesionidae). Its original description, based upon a single specimen collected in Hong Kong waters, was brief; its illustrations were published almost 50 years afterwards, and the type specimen was dried out before it could be redescribed. The late Marian Pettibone redescribed the species in 1970 but her illustrations of the species were based on specimens from the Mediterranean Sea, the Virgin Islands, and Samoa, not Hong Kong. In order to define the morphological features, we herein redescribe this species based upon newly collected specimens from the type locality. This species is characterized by the following features: prostomium subrectangular with a posterior notch, lateral antennae slightly longer than palps, palps with palpophores about 2.5 times longer than palpostyles, anterior eyes twice larger than posterior ones, slightly emarginated, posterior ones circular, median antenna fixed slightly ahead of posterior eyes, nuchal organs C-shaped; pharynx with a prominent dorsal papilla, a mid-dorsal jaw and a mid-ventral jaw; first four chaetigers subbiramous, others biramous with neuroacicular lobes blunt, as long as wide, or longer than wide; notochaetae spinulose capillaries; most neurochaetae with blades bidentate, guards approaching subdistal tooth; a few neurochaetae with long, tapered hoods. A key to identify all species in the genus is also included.

A revision of Holothuria (Halodeima) kefersteinii (Selenka, 1867) and the revival of Holothuria inornata Semper, 1868 from sea cucumbers collected in Mexico and Central America.

In 1958 Deichmann synonymized Holothuria inornata Semper, 1868 with Holothuria kefersteinii (Selenka, 1867). This nomenclature has been adopted until now. However, some specimens recently collected from the Mexican Pacific matched the original description of H. inornata Semper (1868) whereas others matched the original description by Selenka (1867). A morphological, molecular and ecological study of the specimens was conducted to confirm the identification of these specimens. The morphological characters of our specimens were compared with those contained in the original descriptions and figures of the types of both species. Besides the different color pattern of live specimens of both species, the main differences found are the presence of straight distally perforated rods in the dorsal papillae, and the presence of Holothuriophilus trapeziformis Nauck, 1880 in the cloaca of H. inornata, versus the absence of these kind of rods in the dorsal papillae, and the absence of symbionts in the cloaca in H. kefersteinii. The species identified by Deichmann (1958) as H. kefersteinii is, in fact H. inornata. Both species might have been confused because the morphology of preserved specimens is very similar and the presence of the straight rods in papillae might have been overlooked during identification. A more thorough review of the ossicles from the specimens, together with the comparison of ossicles from the type specimens, has allowed the resurrection of long-forgotten species, H. inornata.

Redescription of the Siamese shield leech Placobdelloides siamensis with new host species and geographic range.

The Siamese shield leech Placobdelloides siamensis (Oka, 1917) Sawyer, 1986 (Euhirudinea: Glossiphoniidae) was collected from five new host species, Southeastern Asian Box Turtle (Cuora amboinensis), Yellow-headed Temple Turtle (Heosemys annandalii), Malayan Snail-eating Turtle (Malayemys macrocephala), Mekong Snail-eating Turtle (M. subtrijuga), and Khorat Snail-eating Turtle (M. khoratensis) and was found for the first time in Udon Thani, Thailand. Examination of live leeches provided, for the first time, data on coloration and the combination of parental care behavior, both carrying cocoons and attaching cocoons to the substrate. This species was separated from its congeners based on the following characters: one pair of eyes; spines at proboscis subterminal; mouth terminal on oral sucker; absent plaque in neck region; gonopores located in furrow and separated by two annuli; distinctly triannulated mid-body segments; crop with seven pairs and branched caeca; caudal sucker slightly over half of maximum body width; and strongly dorsal papillae. Phylogenetic relationships based on the COI and ND1 genes were clarified and demonstrated that the species is distinct from others. The original description was amended and the taxonomic history is discussed.

Aspects of digestive function in sheep related to phenotypic variation in methane emissions

Ruminant livestock contribute to atmospheric methane (CH4) from enteric microbial fermentation of feed in the reticulo-rumen. Our research aimed to increase understanding of how digestive characteristics and rumen anatomy of the host animal contribute to variation in CH4 emissions between individual sheep. In total, 64 ewes were used in an incomplete block experiment with four experimental test periods (blocks). Ewes were chosen to represent the diversity of phenotypic variation in CH4 emissions: there were at least 10 offspring from each of four sires and a range of liveweights. Throughout the experiment, the ewes were fed equal parts of lucerne and oaten chaff, twice daily, at 1.5 times the maintenance requirements. Daily CH4 emission (g/day) increased significantly (P < 0.001) with an increasing dry-matter intake (DMI) and reticulo-rumen volume (P < 0.001). Lower methane yield (g CH4/kg DMI) was associated with shorter mean retention times of liquid (r = 0.59; P < 0.05) and particle (r = 0.63; P < 0.05) phases of the digesta in the rumen. Significant between sire variation was observed in CH4 emissions and in rumen volume (P = 0.02), the masses of liquids (P = 0.009) and particles (P < 0.03) in the rumen and the proportion of gas in the dorsal sac of the rumen (P = 0.008). The best predictors of variation in CH4 emissions due to the host were DMI, CO2 emissions, rumen volume, liveweight, mean retention time of particles in the rumen, dorsal papillae density and the proportion of liquid in the contents of the rumen compartments.

A new large oregoniid spider crab of the genus Pleistacantha Miers, 1879, from the Bay of Bengal, India (Crustacea, Brachyura, Majoidea).

A new species of deep-water oregoniid spider crab of the genus Pleistacantha Miers, 1879, is described from the Indian Ocean. The species is distinct in possessing a prominently inflated carapace in which the median parts of the branchial regions almost meet. It can also be distinguished from its closest congeners, P. moseleyi (Miers, 1885), P. pungens (Wood-Mason, in Wood-Mason & Alcock, 1891), and P. ori Ahyong & Ng, 2007, in its more elongate and less spinose chelipeds and ambulatory legs, shorter third maxilliped, trapezoidal male pleon and a male first gonopod which is relatively stout with a short subdistal dorsal papilla.

Morphological variation in invasive mosquito Culex quinquefasciatus Say (Diptera: Culicidae) larvae from an urban site in Auckland, New Zealand

ABSTRACTLarvae of the invasive mosquito Culex quinquefasciatus Say are morphologically similar to those of the native Culex pervigilans Bergroth, yet distinguishing these species can be hampered by morphological variations in Cx. quinquefasciatus. We present detail about the extent of these variations in an urban population of Cx. quinquefasciatus in Auckland. To aid in identification of this exotic species, we provide images of key diagnostic characters and some observed exceptions to these. Details regarding variation in diagnostic characters for < 3rd instar and 3rd/4th instar larvae are given. Of the nine characters used for identification, three were highly consistent (dorsal papillae, mantle plate, pecten teeth); each observed in > 90% of larvae, although these characters were not always visible. Other characters were less reliable, for instance, the expected position of seta 1a-S in relation to the pecten teeth was observed in < 10% of larvae. Further exploration of regional morphological variation in both Cx. quinquefasciatus and Cx. pervigilans is recommended, ideally with associated molecular characterisation.

Psolus rufus, a new species of sea cucumber (Holothuroidea: Psolidae) from northern Spain (Bay of Biscay)

A new species of holothurian of the genusPsolusOken, 1815 is described.Psolus rufussp. nov. was found in the central Cantabrian slope (Bay of Biscay) at 1500 m depth. The new species is characterized by having: ovoid body, reddish colourin vivo; dorsal area enclosed in a complete test composed of imbricating scales; 10 triangular plates of the same size surrounding mouth; 10 oral tentacles; no dorsal papillae; tube feet in two rows in the ventrolateral radii but one single row in the medial third or the body; ossicles are big dorsal plates and small plates in the sole, which are smooth, irregular and perforated. The molecular study of the COI gene supports the morphological results, groupingP. rufussp. nov. together with other members of the genus. However, the new species is genetically distinct from the two groups (Antarctic and Canadian) of the available sequencedPsolusspecies. Furthermore, a key to thePsolusspecies of the north-eastern Atlantic Ocean is provided.

Didymodon vulcanicus J.A.Jiménez, Hedd. & Frank Müll. (Pottiaceae), a new species from tropical Africa

Didymodon vulcanicus J.A.Jiménez, Hedd. & Frank Müll. is described and illustrated as a new species from volcanic regions of tropical Africa. The species is distinguished morphologically by its lanceolate or more rarely ovate-lanceolate leaves that are strongly incurved distally when dry, acute apices, upper and middle laminal cells arranged in longitudinal rows with a low dorsal papilla over the transverse walls which reaches the two immediate cells, basal cells not or hardly differentiated from the medial cells, and the presence of gemmae in the leaf axils. Drawings and light microscope photographs of the main characters are given, and possible confusion with other closely related taxa is discussed.

A new species of Nebalia (Crustacea, Leptostraca) from coral reefs at Pulau Payar, Malaysia

A new species of Leptostraca, Nebalia terazakii sp. n. is described and figured. The species was sampled from the coral reefs of Pulau Payar Marine Park, Langkawi, Malaysia. There are 32 existing species of Nebalia but Nebalia terazakii sp. n. can be distinguished from the other known species of Nebalia by the following combination of characters: the rostrum is 1.89 times as long as wide and the eyes have no dorsal papilla or lobes. Article 4 of the antennular peduncle has one short thick distal spine. The proximal article of the endopod of maxilla 2 is shorter than the distal, a feature peculiar to Nebalia terazakii sp. n., the exopod of maxilla 2 is longer than article 1 of the endopod, the posterior dorsal borders of the pleonites 6 to 7 are provided with distally sharp denticles, anal plate with prominent lateral shoulder and finally, the terminal seta of the caudal rami is 1.17 times the length of the entire rami.

First report of Leptostraca from South-east Asia:Nebalia cambodianasp. nov. (Crustacea: Malacostraca)

A new species of Leptostraca,Nebalia cambodianasp. nov. (Crustacea: Malacostraca), is described from Cambodia. The specimen was collected by light traps on a diving deck where the bottom consisted of fine sand and gravel. The new species is distinguished from all other known species ofNebaliaby the following characteristics: rostrum very long, length nearly 3.5 times width; a compound eye with one distinct dorsal papilla and four small lobes on distal margin; an antennular flagellum with nine articles; the fourth article of the antennular peduncle with only one distal thick seta; the antennular scale is elliptical, with a length that is 2 times the width; exopod of the second maxilla is the same length as first article of its endopod; pleonites 5 to 7 with rounded denticles along their posterior dorsal margins; the protopod of pleopod 4 lacks serration along the posterior margin; and anal plates with distinct lateral ‘shoulder’.The new species is the first species of Leptostraca found in South-east Asia. In this paper, we provide illustrations and a detailed description of the diagnostic characteristics ofN. cambodianasp. nov.

Redescription and biology of Diopatra neapolitana (Annelida: Onuphidae), a protandric hermaphrodite with external spermaducal papillae

A one-year study of the reproductive biology of a population of Diopatra neapolitana at Villaviciosa estuary, northern Spain, was undertaken. Field observations together with a histological study of monthly collected individuals revealed that the population was iteroparous, had a discontinuous reproductive season with a resting period during August and September and a spawning season from March to July. The study showed that D. neapolitana was not dioecious as previously suggested but consisted of protandric sequential hermaphrodites, pure males and pure females with a male biased sex ratio of 3:1. During the peak reproductive period from May to August we observed simultaneous hermaphrodites with two dorsal papillae per segment in the branchial region. Histological studies demonstrated that the papillae were acting as seminal vesicles, storing own sperm, and also as sperm ducts, providing an exit route; hence we termed them ‘spermaducal papillae’. The papillae are not the only sperm repositories as the coelom of males and simultaneous hermaphrodites in smaller size classes is also filled with sperm. The worms are broadcast spawners with a brief pelagic larval stage as previously reported but the finer points of this unusual fertilisation system need still to be elaborated. Diopatra cryptornata was recently described as a new species, supposedly differing from D. neapolitana in chaetal detail and the possession of the papillae. We have shown conclusively with morphological and genetical studies that the former species is a junior synonym of the latter. In the absence of type material we are here designating a neotype from recently collected material from Naples.

Nephtys sachalinensis sp. n. (Annelida: Nephtyidae): a new species from the upper sublittoral zone of northeastern Sakhalin Island, the Sea of Okhotsk

A new species of nephtyid polychaetes Nephtys sachalinensis sp. n. from the upper sublittoral zone (at a depth of 10–107 m) off Northeast Sakhalin, the Sea of Okhotsk, is described. Diagnostic characters of adults are: an everted pharynx with 20 bifid terminal and 2 median simple terminal papillae; single median dorsal and ventral pharyngeal subterminal papillae absent; proximal and median parts of the pharynx are covered with verrucae; branchiae begin from the fourth chaetiger; acicular lobes are distinctly bilobed from the anterior chaetigers almost to the end of the body; each acicular lobe (both in notoand neuropodia) has one rounded outgrowth on its interramal side; subulate notopodial cirri at the median and posterior chaetigers; neuropodial postacicular lobes are no more than two times longer than the acicular lobes. The new species is compared with its related species.

The Effects of Yeast Culture Products on Fattening Performance, Rumen Papilla Morphology, Some Blood and Rumen Fluid Parameters in Saanen Male Kids

The aim of this study was to investigate the effects of live yeast culture and the live yeast culture enriched with vitamin-mineral supplementation as a feed additive on fattening performance, some blood and rumen fluid parameters in male kids. Totally 18 male Saanen goat kids (average 8 weeks old) were divided into one control and two treatment groups each containing 6 kids. Rations were prepared as isonitrojenic and isocaloric. Live yeast culture (LYC) and the yeast-vitamin-mineral complex (YVM) (RumiSacc® and Intetotal® respectively, Integro food Industry and Trade Co., Istanbul, Turkey, Live yeast cell 344 x 1010 cfu/g,) were incorporated into concentrates at the level of 0% (C), 1% (YC) and 1% (YVM) on as-fed basis. During the study concentrate feed and fresh water were given ad libitum and the ration did not contain any roughages. Dietary yeast culture at the level of 1% increased final live weight (4.7% regarding control group) as numerically but not significantly. The fattening performance, rumen fluid and blood parameters were not statistically affected from the dietary treatments throughout the study. While the dorsal papillae length was not changed, ventral papillae length was decreased in the treatment groups. The length of papillae in YVM groups were similar to that of control groups.

Macroperipatus ohausi: redescripción y notas taxonómicas sobre su estatus (Onychophora: Peripatidae)

Onychophora have undergone a new wave of taxonomic revisions in the last three years. After a recent revision, only two species of Macroperipatus are registered from Brazil: Macroperipatus ohausi and Macroperipatus geayi. The former was only the second species of Onychophora to be described from Brazil, and is herein redescribed, illustrated, and its taxonomic status revised. Macroperipatus ohausi had only been collected at the type locality, Petrópolis, state of Rio de Janeiro, but has not been found there since its discovery. In 2009 we collected two specimens of this species in an Atlantic rain forest fragment in Nova Iguaçu in RPPN dos Petroleiros (also state of Rio de Janeiro). The color of the new specimens was interpreted and described based on the NBS/ISCC System of Color Designation, and corresponds only weakly to that described in earlier publications on M ohausi. The identification of M. ohausi was based solely on its morphology and compared with its original description. In addition, a female syntype of M. ohausi deposited in the Zoologisches Museum (Hamburg) was examined. We reinvestigated its external morphology and concluded that the dorsal papillae have been misinterpreted in M ohausi in previous studies of its integument. The new specimens examined are conspecific with M ohausi mainly by having conical primary papillae, different sized accessory papillae, and by the number of legs. Our material resembles.the original description of M ohausi, for example, in spinous pad and nephridial tubercles, even though these features are not represented in the original description and redescription ofM. ohausi; these features are further detailed here. We concluded that the dorsal papillae morphology of M ohausi, shares diagnostic characters, for example, with representatives of the genera Peripatus and Epiperipatus. The dorsal papillae are rounded and not square as in the original description and redescription. Another argument that supports our conclusion is that the RPPN dos Petroleiros, the locality where the new samples were collected, belongs to the same mountain chain and Atlantic mosaic as the original material of M ohausi. Furthermore, a male of M. ohausi is described here for the first time. Based on our morphological data, we transfered this species to the genus Epiperipatus, proposing a new combination, E. ohausi.

Aspects of the morphology of the juvenile life stages of Paradiplozoon ichthyoxanthon Avenant-Oldewage, 2013 (Monogenea: Diplozoidae)

There are eight life stages in the life-cycle of Diplozoon paradoxum and limited knowledge of the life-cycle for other diplozoid genera exists. The aim of this study was to record the number of life-stages of Paradiplozoon ichthyoxanthon obtained from, Labeobarbus aeneus and Labeobarbus kimberlyensis, in the Vaal Dam from 2005 to 2007. Six larval life stages and one adult stage of P. ichtyoxanthon were identified from specimens collected in vitro and in situ. In vitro, eggs hatched after 21 days at 18°C. Eggs collected during winter were significantly larger than those laid during spring or summer. Paradiplozoon ichthyoxanthon oncomiracidia have peripheral eyes with pink pigmentation, a tubular anterior bladder-like structure, bicuspid basal pharynx valve and a branched digestive caecum and residual shell material or vitellaria in the caecum. Immature reproductive tissue connected to the ventral sucker and dorsal papillae were noted for the first time in diporpa. Large nervous ganglia and innervation of muscle were observed around the ventral sucker.

A new species of Helobdella (Hirudinida: Glossiphoniidae) from Oregon, USA.

Helobdella bowermani n. sp. is described from specimens collected in fine sediment of open water benthos of Upper Klamath Lake, Klamath County, Oregon. The new species has pale yellow/buff coloration with scattered chromatophore blotches throughout the dorsal surface, lateral extensions or papillae only on the a2 annulus, dorsal medial row of papillae with small papilla on al and larger papillae on a2 and a3, and a small oval scute (rarely triangular). Helobdella bowermani n. sp. is morphologically similar to Helobdella atli and Helobdella simplex. Molecular comparison of CO-I sequence data from H. bowermani n. sp. revealed differences of 10.6/--10.8% with Helobdella californica, differences of 12.2%-13.7% with H. atli, and differences of 12.7%-13.2% with H. simplex.

Holothuria (Semperothuria) roseomaculata n. sp. (Aspidochirotida: Holothuriidae), a coral-reef inhabiting sea cucumber from the western Pacific Ocean.

Holothuria (Semperothuria) roseomaculata n. sp. is described from the main islands of Yap, Federated States of Micronesia. The ossicles are similar to those of its sister species, the sympatric H. (S.) flavomaculata Semper, 1868, but the new species is easily recognised, both in the field and among preserved specimens, by its much larger, rose-coloured dorsal papillae that fade to white in alcohol. Holothuria (S.) roseomaculata n. sp. appears to be an endemic of the tropical westernmost Pacific Ocean; it has been recorded from Okinawa to New Caledonia.

Cuttlefish skin papilla morphology suggests a muscular hydrostatic function for rapid changeability

Coleoid cephalopods adaptively change their body patterns (color, contrast, locomotion, posture, and texture) for camouflage and signaling. Benthic octopuses and cuttlefish possess the capability, unique in the animal kingdom, to dramatically and quickly change their skin from smooth and flat to rugose and three-dimensional. The organs responsible for this physical change are the skin papillae, whose biomechanics have not been investigated. In this study, small dorsal papillae from cuttlefish (Sepia officinalis) were preserved in their retracted or extended state, and examined with a variety of histological techniques including brightfield, confocal, and scanning electron microscopy. Analyses revealed that papillae are composed of an extensive network of dermal erector muscles, some of which are arranged in concentric rings while others extend across each papilla's diameter. Like cephalopod arms, tentacles, and suckers, skin papillae appear to function as muscular hydrostats. The collective action of dermal erector muscles provides both movement and structural support in the absence of rigid supporting elements. Specifically, concentric circular dermal erector muscles near the papilla's base contract and push the overlying tissue upward and away from the mantle surface, while horizontally arranged dermal erector muscles pull the papilla's perimeter toward its center and determine its shape. Each papilla has a white tip, which is produced by structural light reflectors (leucophores and iridophores) that lie between the papilla's muscular core and the skin layer that contains the pigmented chromatophores. In extended papillae, the connective tissue layer appeared thinner above the papilla's apex than in surrounding areas. This result suggests that papilla extension might create tension in the overlying connective tissue and chromatophore layers, storing energy for elastic retraction. Numerous, thin subepidermal muscles form a meshwork between the chromatophore layer and the epidermis and putatively provide active papillary retraction.

Two new species of Sphaerodoropsis Hartman & Fauchald, 1971 (Polychaeta: Sphaerodoridae) from Iceland (BIOICE programme)

Two new species of Sphaerodoropsis Hartman & Fauchald, 1971 (Polychaeta: Sphaerodoridae), collected during the BIOICE programme on sedimentary bottoms off Iceland, are described. Sphaerodoropsis gudmunduri sp. nov. is a shelf species (<400 m) chiefly characterized by having one transverse row of up to 10–12 dorsal macrotubercles per chaetiger (‘Sphaerodoropsis group 2’) and body papillae present only on the prostomium, peristomium, parapodia and ventral surface. It also has up to 7–9 ventral papillae per chaetiger arranged following a non-random pattern and parapodia which bear one digitiform prechaetal lobe, 1–4 papillae and compound unidentate chaetae with blades with thin spinulation along their cutting edge. Sphaerodoropsis halldori sp. nov. has been found in deeper waters (>1000 m) and may be distinguished mostly by having up to 13 dorsal macrotubercles arranged in two transverse rows (6–7 macrotubercles, respectively) defining a zig-zag pattern (‘group 3’) and 7 dorsal papillae per chaetiger, up to 8–10 ventral papillae per chaetiger arranged in a non-random pattern and parapodia which bear one digitiform prechaetal lobe, one antero-lateral papilla and compound unidentate chaetae with blades with thin spinulation along their cutting edge. Both species show sexual dimorphism characterized by different arrangements of modified ventral cirri and/or special ventral structures in some mid-body chaetigers; a brief discussion about the presence of these structures on sphaerodorids and their possible importance on the systematics of the family is provided.