Periacineta mexicana n. sp. (Ciliophora,Suctoria, Discophryida), Epizoic on Mexican Backswimmers of the Genus Buenoa (Insecta,Hemiptera, Notonectidae)

ABSTRACT. A new species of suctorian in the genus Periacineta, epibiotic on aquatic bugs (Hemiptera, Heteroptera, Nepomorpha), is described on the basis of morphological characteristics of the cell body, lorica, tentacular placement, and stalk, and its 18S rRNA partial sequence gene. Periacineta mexicana n. sp. is a loricate suctorian with elongate body and rounded apical region; tentacles are distributed randomly over apical region and not grouped into fascicles. Macronucleus in adult is elongate and located centrally. The suctorian usually forms closely aggregated pseudocolonies. We provide morphological data based on optical and scanning electron microscopy. A comparison with similar congeners, and emended diagnosis of the genus Periacineta also are provided. The ciliates were found attached to the first two pairs of legs of Mexican notonectids Buenoa pallens and Buenoa spp. (backswimmers).     

Development of the tentacular apparatus in sipunculans (Sipuncula): I. Thysanocardia nigra (Ikeda, 1904) and Themiste pyroides (Chamberlin, 1920)

The development and arrangement of the tentacular apparatus of Thysanocardia nigra (Ikeda, 1904) and Themiste pyroides (Chamberlin, 1920) are described and illustrated using scanning electron microscopy. In T. nigra, the tentacular apparatus is composed of two crowns: the nuchal arc enclosing the nuchal organ and a crown of numerous oral tentacles arranged in U-shaped festoons. In early juveniles, two dorsal horn-like protrusions develop into the first, or primary, pair of tentacles of the nuchal arc. The second pair of tentacles of the nuchal arc develops dorsolaterally on the bases of the primary tentacles. Two ventrolateral lobes of the oral disk grow and become subdivided by the longitudinal ciliary groove into anlages of one set of dorsal and one set of ventral tentacles, thus forming a first oral festoon. Later, a pair of dorsolateral lobes develop between the first festoons and the nuchal arc to form a second pair of oral festoons. The third and following pairs of oral festoons develop in the dorsolateral growth zones lateral to the borders of the nuchal arc, where they meet the oral crown. The growing festoons extend down the oral disk and run alongside the head. A new oral tentacle appears directly at/on the base of the previous tentacle, thus giving rise to a typical sympodium with an alternating arrangement of tentacles. In T. pyroides, a second pair of tentacles develops from two ciliary lobes that are ventrolateral outgrowths of the circumoral ciliary field around the terminal mouth opening. The third pair of tentacles appears from the dorsolateral lobes at the base of primary tentacles, between the first two pairs of tentacles. These six tentacles determine the position of six main stems of the tentacular apparatus designated the first tentacles in the corresponding stems. The second tentacle in every stem appears as a ventrolateral outgrowth at the base of the first tentacle. The third and following tentacles in the stem are developed between the two previous tentacles according to a sympodial pattern. In both species, the distinct sympodial pattern in the arrangement of tentacles in the tentacular apparatus is well evidenced by the outlines of the ciliary oral grooves. The branched stems of T. pyroides may be homologized structurally and functionally to the oral festoons of T. nigra. J. Morphol. (c) 2006 Wiley-Liss, Inc.     

A new species of Amphictene (Annelida,Pectinariidae) from the Gulf of Mexico,with a redescription of Amphictene guatemalensis (Nilsson, 1928)

The genus Amphictene is reported for the first time from Mexico. Previous records for America are restricted to Brazil (Amphictene catharinensis) (Grube, 1870), and Guatemala (Amphictene guatemalensis) (Nilsson, 1928). In this paper we describe a new species, Amphictene helenae sp. n., characterized by the presence of three pairs of tentacular cirri, while other species have only two pairs. The new species is closely similar to Amphictene catharinensis, and can be distinguished by the presence of a circular group of glandular papillae inserted between the lines of glandular cirri present from the second segment. Amphictene guatemalensis is redescribed based on type material; it differs from the new species in the presence of two pairs of tentacular cirri on segments 1 and 2, six pairs of glandular cirri on the third segment, and four glandular lobes fused in pairs on the fourth segment.     

团头鲂寄生吸管虫一新种,双泡毛管虫的研究

描述了寄生在团头鲂(Megalobrama amblycephala)鳃上的一吸管虫新种,双泡毛管虫。活体无色透明至淡黄色,正面观为卵圆形至长椭圆形,稍扁平;侧面观为棒状或香肠状,常附着在鳃小片上。身体的表膜中有不明显的细小颗粒。吸管指状,一束,着生在虫体前端,一般有4—8根,最多达23根,收缩时其表面出现明显的螺旋纹8—11个。两个伸缩泡,交替地进行伸缩,彼此间隔约为10μm,位于吸管基部的胞质中。大核短杆状或椭圆形,核膜明显,染色质均匀。小核圆球形。成虫和幼虫没有固着柄,游泳幼虫的纤毛带宽6.0—7.0μm,由7—11行纤毛纹组成,无锥形的钻孔器。       

Presence of two suctorian ciliate species of the genera Acineta and Pelagacineta, epibionts on marine copepod crustaceans

Acineta arcachoniensis sp. nov., a new species of protist suctorian epibiont on the copepod Chiridius gracilis is described. The individuals show two well-developed actinophores, with two fascicles of capitate tentacles, an irregular nucleus, a cup-shaped lorica and a short stalk. Reproduction of A. arcachoniensis is by endogenous budding. The suctorians are located on the base of the antennae, the final abdominal segments or on the last pereiopod pair of the copepod. In addition, a new registration of the suctorian Pelagacineta euchaetae on the copepod Calanus helgolandicus is recorded.     

A new genus of Syllidae (Polychaeta) from Western Australia

During a study carried out on the subfamily Exogoninae (Syllidae) from Australia, several specimens of a new genus and species were found in samples of dead coral substrate from Western Australia. They have long palps, fused except for a terminal notch, long median and two short lateral antennae, a single pair of short tentacular cirri, and short dorsal cirri, somewhat longer than the parapodial lobes. These characters resemble those of the genus Exogone Örsted, 1845. However, all these appendages are articulated. The chaetae are very similar to those of several species of Syllis Lamarck, 1818, having coarse spines on the margin of compound chaetal blades and truncated dorsal simple chaetae. Furthermore, the pharynx begins in chaetiger 3, posterior to the peristomium, as in many species of the genus Syllis; this condition does not occur in any described species of Exogone. The new genus is provisionally proposed to belong to the subfamily Syllinae, although it has some characters typical of the Exogoninae. Examination under the SEM shows another peculiar feature, the nuchal organs are distinctly laterally located. Within the Syllinae, only Paratyposyllis Hartmann-Schröder, 1962 has a single pair of tentacular cirri, but in that genus, the palps are only basally fused.     

Intestinal ciliate fauna of the Asian elephant from Gaziantep,Turkey and the description of Brevitentaculum antebum n. g., n. sp.

The aims of this investigation were to identify and quantify ciliates inhabiting the large intestine of Asian elephants living in Gaziantep Zoo, Turkey, and to describe a new suctorian genus and species. Species composition and distribution of intestinal ciliates voided in the feces of two Asian elephants were examined. Fifteen species of intestinal ciliates, representing 7 genera, were identified. One new suctorian genus and species, Brevitentaculum antebum n. g., n. sp., was described. This new species has two short truncated terminal projections, with two longitudinally lined bands located between the two projections, near the convex surface of the cell. Short clavate-like tentacles are in two fascicles near each base of terminal projections on the flattened surface of the body. Ciliate densities in the two fecal samples were 4.5 × 10⁴ mL⁻¹ and 10 × 10⁴ mL⁻¹.     

Mussaenda lancipetala X. F. Deng & D. X. Zhang,a new species of Rubiaceae from China

Mussaenda lancipetala X. F. Deng & D. X. Zhang, a new species of Rubiaceae from Yunnan Province, Southwestern China, is described and illustrated. The new species is characterized by its reverse herkogamous sexual system, its ovate-lanceolate corolla lobes with caudate apex, and corolla tube covered with sparse farinose pubescence, by which it is clearly distinguished from other species of Mussaenda.     

中国玉叶金花属(茜草科)植物一新种

报道了在云南发现的玉叶金花属Mussaenda一新种——狭瓣玉叶金花M. lancipetala X. F. Deng ＆ D. X. Zhang。狭瓣玉叶金花的性系统为柱头缩入式雌雄异位; 花冠裂片卵状披针形且具有细长的长尖头, 花冠管外被有粉末状的毛被, 可以很容易与玉叶金花属其他种类相区别。     

Redescriptions of species of Tetrarhynchobothrium Diesing, 1850 and Didymorhynchus Beveridge & Campbell, 1988 (Cestoda: Trypanorhyncha), with the description of Zygorhynchus borneensis n. sp

Tetrarhynchobothrium tenuicolle Diesing, 1850 is redescribed from the type-specimens collected from Raja clavata Linnaeus in the Adriatic Sea. T. striatum (Wagener, 1854) is redescribed from voucher specimens from the type host, Myliobatis aquila Linnaeus, from the type-locality, off Naples, Italy. The two species are very similar in tentacular armature, but are provisionally maintained as independent species, since the armature of T. tenuicolle cannot be fully described and because all available specimens of T. striatum are immature, limiting comparisons of potential differences in segment anatomy. T. setiense Dollfus, 1969 is treated as a synonym of T. striatum. Zygorhynchus borneensis n. sp. is described from Himantura uarnacoides (Bleeker) and H. pastinacoides (Bleeker) off Sabah, Malaysia. The new species is distinguished from its congeners by the very small hooks present in the basal region and by the presence of a uterine pore. The metabasal tentacular armature of Didymorhynchus southwelli Beveridge & Campbell, 1988, described for the first time, is homeoacanthous and homeomorphous in form. However, it has a basal swelling with hook rows originating on the bothrial surface and terminating on the antibothrial surface of the tentacle.     

Systematics and distribution of the New Zealand onychoteuthid fauna (Cephalopoda: Oegopsida), including a new species, Notonykia nesisi sp. nov.

Onychoteuthid squids are among the most common cephalopods found in New Zealand waters, and comprise a major portion of the regional diets of teuthophagous marine mammals. Although several recent publications have addressed aspects of various species’ biology and reproduction, the systematics of the group remains poorly understood. Herein the ontogenetic and adult morphologies of regionally occurring known species of the genera Moroteuthis, Onychoteuthis, and Notonykia are redescribed, and Notonykia nesisi sp. nov. is described for the first time. Ontogenetic and sexually dimorphic variation in characters and character states associated with body proportions, and beak, radula, tentacular hook, palatine tooth and gladius morphologies are also described and compared between local onychoteuthid taxa for the first time.     

<Emphasis Type="Italic">Nephtys yuryi</Emphasis> sp. n. (Annelida: Nephtyidae): a new species from the Northwest Atlantic

A new species of nephtyid polychaete habiting from the sublittoral to the continental slope (depth 14–500 m) of the Northwest Atlantic is described. The most significant characters of adults are: interramal parts of the preacicular lobes are wrapped around the acicular lobes; interramal parts of the neuropodial postacicular lobes and interramal parts of the postacicular rows of neurochaetae wrapped around the acicular and preacicular lobes; interramal parts of the postacicular rows of notochaetae wrapped around the acicular and preacicular lobes and covered by the bases of the notopodial cirri. Comparison with other species of the genus is provided.     

Dischidia kerrii sp. nov. (Apocynaceae: Asclepiadoideae) from northeastern Thailand

Dischidia kerrii is presented as a new species from northeastern Thailand. This newly discovered species is thoroughly described, discussed and illustrated. A comparison is made with the putative closely related species D. acuminata. They can be distinguished by differences in corolla lobes and staminal corona lobes.     

Ultrastructural and Other Observations Which Suggest Suctorian Affinities for the Taxonomically Enigmatic Ciliate Cyathodinium*

SYNOPSIS. Two species of the taxonomically enigmatic genus Cyathodinium, C. piriforme and C. cunhai, were studied in some detail at both light and electron microscopic levels. Data obtained strongly suggest suctorian affinities for the genus, since a number of structures or features are strikingly reminiscent of similar (if not homologous) structures recently discovered in ciliates belonging to the order Suctorida. Endosprits (suctorial tentacles?) of Cyathodinium show an arrangement of microtubules not unlike that known for several suctorians, especially Acineta and Tokophrya. Haptocysts or missile-like bodies, ca. 600 mμ long, have been observed within endosprits and free in the cytoplasm; again this is reminiscent of the complex organelles recently described from several suctorian groups. Mouthlessness, coupled with the presence of a ventral depression (functioning in gathering prey at distal ends of endosprits?) and the presence of food vacuoles in the cytoplasm, further support a suctorian mode of feeding. Finally, stages in the curious life cycle of Cyathodinium suggest neoteny and a basic similarity to endogenous budding processes in certain suctorians.     

A hydrothermal vent mite (Halacaridae,Acari) with a new Corynophrya species (Suctoria,Ciliophora), description of the suctorian and its distribution on the halacarid mite

Copidognathus nautilei Bartsch, 1997, from a hydrothermal vent field of the Mid-Atlantic Ridge at about 13°N, 45°W and 4090 m depth, was infested with the suctorian Corynophrya abyssalis n. sp., with up to 58 epizoans per mite. The new suctorian has a sacciform body with seven longitudinal ribs, a compact macronucleus and up to 40 non-retractile tentacles. The budding is exogenous. The systematic position of the new species and the genus Corynophrya is discussed, as well as infestation rates and sites of suctorians on their halacarid hosts.     

Digeneans of fishes from the Adriatic Sea with a description of Lecithaster atherinae n. sp. from Atherina (Hepsetia) boyeri

A collection of whole mount preparations of digeneans was studied. The parasites were collected from several species of fishes caught in a fishing area of the South Adriatic Sea. A host-parasite list is given. Twenty species of fish were analysed and twenty-seven species of digeneans were found, twenty of which had previously been described in the same host, and six of which were observed in new hosts and/or localities. One digenean, hitherto undescribed, is illustrated in this paper and described as Lecithaster atherinae n.sp. The new species can be distinguished from L. bombayensis by the testes not being lobed; from L. extralobus by having four rather than five ovarian lobes; from L. indicus and L. maeoticus by the ovarian lobes not being finger-like; from L. leiostomi by having definitely smaller eggs.     

Gastrodia sui sp. nov. (Orchidaceae) from Taiwan

A new orchid species, Gastrodia sui C. S. Leou, T. C. Hsu & C. L. Yeh is described and illustrated from Taiwan. The new species is closely related to G. callosa J. J. Sm. but distinguishable by the number and position of calli inside the perianth tube, the fused ratio of perianth lobes, and the structure of the lip and column. It is so far only found in the area of Mt Lilung in southern Taiwan.     

Ceropegia thaithongiae sp. nov. (Apocynaceae,Asclepiadoideae) from northern Thailand and preliminary observations on impacts of climate change on its only known population

A new pendulous herb, Ceropegia thaithongiae Kidyoo (Apocynaceae, Asclepiadoideae), is described from northern Thailand. This plant is strictly endemic to Chiang Dao Wildlife Sanctuary and critically endangered owing to it living in an ecosystem affected by frequent natural disturbances. It is here described, illustrated and compared to the similar species, C. mairei. Both species have fusiform rootstocks, 1–2‐flowered cymes, deeply bifid outer corona lobes and linear, hairy inner corona lobes. However, the new species can be distinguished by its glabrous stem, leaf covered with hairs on both surfaces and glabrous corolla tube and lobes.     

Ancipirhynchus afossalis n. g., n. sp. (Trypanorhyncha: Otobothriidae), from two species of sharks off Indonesian and Malaysian Borneo

A new genus of trypanorhynch cestode is described from two species of sharks, the sliteye shark Loxodon macrorhinus Müller & Henle and the straight-tooth weasel shark Paragaleus tengi (Chen) collected in the Makassar Strait (off Indonesian Borneo) and Sulu Sea (off Malaysian Borneo). Ancipirhynchus afossalis n. g., n. sp. possesses two bothria and a heteroacanthous, heteromorphous tentacular armature with three distinctive files of hooks on the external tentacle surface but lacks prebulbar organs and gland cells within the tentacular bulbs. The hook arrangement of alternating files on the external surface of the tentacle resembles that seen in the superfamily Otobothrioidea Dollfus, 1942 in the genus Fossobothrium Beveridge & Campbell, 2005. However, the new species lacks the defining characteristic of this group, i.e. the paired bothrial pits. A Bayesian inference (BI) analysis of 37 LSU sequences of trypanorhynchs from three superfamilies provided evidence supporting the taxonomic placement of Ancipirhynchus afossalis n. g., n. sp. within the Otobothrioidea.     

Description of Bucephalus anguillae n. sp. (Trematoda: Bucephalidae), a parasite of the eel Anguilla anguilla (Anguillidae) from a brackish water lagoon of the Adriatic Sea

The digenetic trematode Bucephalus anguillae n. sp. is described from the intestine of eel, Anguilla anguilla L., originating from a brackish water fish farm on the Italian coast of the Adriatic Sea. The new taxon is 1 of 12 Bucephalus species characterized by an anterior rhynchus surrounded by 7 tentacular appendages, each when fully protruded with 2 prongs. Scanning electron microscopy reveals, for the first time in a Bucephalus species, the crescent-shaped, unspined field located between the rhynchus and the dorsal tentacles. A comparison of B. anguillae n. sp. with 11 congeneric species revealed its remarkable similarity with B. polymorphus Baer, 1827; however, the new species has a larger cirrus sac, larger pharynx, vitelline gland fields not extending the level of pharynx, ovary located in the pharyngeal area rather than fairly posterior to pharynx, smaller testes, relatively wider rhynchus, and tegumental armature comprising slightly larger spines. Multivariate discriminant analyses confirmed a differentiation of B. anguillae from populations of B. polymorphus; the combination of 4 variables, namely cirrus sac length, pharynx width, cirrus sac width, and rhynchus width yielded a total separation of compared species.