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1.
The intertimdal gastropod Thais malayensis n.sp. (Neogastropoda,Muncidae) is described from Singapore and peninsular Malaysia.Although a common species, it may have been previously overlookedor mistaken for other species found in and near mangroves. Anotherpoorly known species, T javanica (Phdippi) may also have beenconfounded with the new species. New data on their soft parts,radulae, opercula, and egg capsule morphology are presentedto distinguish between these closely related species. (Received 26 February 1996; accepted 15 May 1996) 相似文献
2.
A new, stygobiont species of Hauffenia (Pollonera, 1898) fromnortheastern Austria is described. It has been previously misidentifiedas H. kerschneri (Zimmermann, 1930), but detailed anatomicalinvestigations indicate that it is a separate species. Distinguishingcharacters are the very reduced peg of the operculum, a hypobranchialgland, an anterior lobe of the digestive gland in 25% of thespecimens, and an upright penial stylet. Some animals were infestedwith sporocysts and rediae. (Received 13 September 1991; accepted 1 November 1991) 相似文献
3.
Ghamizi Mohamed; Bodon Marco; Boulal Mokhtar; Giusti Folco 《Journal of Molluscan Studies》1999,65(1):89-98
The new genus Atebbania is described for a new hydrobiid species,A.
bernasconii, which lives in groundwaters of southern Morocco.Of the Hydrobiidae genera
with known shell and anatomy Moitessieriais the closest to Atebbania. The
two share the following characters:shell elongate; teleoconch surface with evident
microsculpture;seminal receptacle absent. Atebbania is distinguished from Moitessieriaby: shell ovate; penis with a) apical stylet, b) one lobe bentdownward on left
(inner) side and c) penial duct running nearthe right (outer) side; posterior end of foot indented. Atebbaniabernasconii n. sp., lives in a limited area, the Tiznit plainin southern
Morocco. Other stygobiont hydrobiids from otherareas of Morocco are currently being studied.
None of them appearsto be closely related to A. bernasconii or to the species ofMoitessieria (Received 10 February 1998; accepted 30 April 1998) 相似文献
4.
Scanning and transmission electron microscopy in conjunctionwith histology and dissection were employed to investigate theforegut anatomy of Sayella fusca (C.B. Adams, 1839), a commonNew England pyramidellid snail. Certain aspects of the feedingapparatus of S. fusca, including the buccal pump and proboscisanatomy, depart from the characteristic pyramidellid plan. Somedifferences such as the position of the introvert/proboscisaperture and the common oral and stylet canal are shared withthe genera Turbonilla, Eulimella, and Pyramidella. Three characteristicsof the feeding apparatus are unique to S. fusca: (1) the buccalpump is not divided into two pouches but exists as a singlemuscular bulb; (2) the entire lumen of the buccal pump, notsimply a portion of it, possesses a cuticular lining; and (3)the salivary ducts never enter the muscular walls of the buccalpump. Histological studies of the salivary gland indicate thatthree types of secretory cells are intermittently distributedthroughout the entire gland rather than characterizing distinctregions as described for other members of the family Pyra-midellidae.In contrast to previous findings, the gland cells of S. fuscaexhibit a merocrine secretion. The taxonomic value of the buccalpump and proboscis morphology are discussed.
*Present address: Dauphin Island Sea Lab, 101 Bienville Boulevard,Post Office Box 369370, Dauphin Island, Alabama 36528USA. (Received 9 November 1993; accepted 1 October 1997) 相似文献
5.
Mytilopsis sallei (Récluz) (Dreissenacea) has been introducedinto Visakhapatnam harbour, India. The normal distribution ofthe species is Central America and it is here contended thatthe species has been introduced into the Indo-Pacific via thePanama canal (opened in 1915) attached to the hulls of ships.M. allyneana (Hertlein & Hanna) with a distribution restrictedto Fiji is considered synonymous with M. sallei. The literature on M. sallei is reviewed and it is shown thatthe species has wide temperature, salinity and oxygen tolerancesand thus transport across a variety of water masses is entirelyfeasible. The species also possesses a fast rate of growth,a high fecundity and matures early. It is an opportunistic specieswhich free from the restraints that normally hold it in checkin its natural environment, poses a serious fouling threat toharbours throughout the Indo-Pacific and to the endemic fauna. The morphological adaptations of M. sallei are also describedand compared with those of Dreissena polymorpha (Pallas) inparticular and other fouling bivalves in general. The speciesis ideally adapted to life in turbid estuaries experiencingwide variations in temperature, salinity, oxygen and turbulence.A warning against further introductions is given. (Received 14 December 1979; 相似文献
6.
The water relations of five species of tropical vascular epiphytesnative to Malaysia were studied. The species were ferns: Pyrrosiaadnascens (Forst.) Ching. and Pyrrosia angustata (Sw.) Ching.;orchids: Eria velutina Lindl., Dendrobium tortile Lindl. andDendrobium crumenatum Sw. Leaf resistance as a function of leafwater potential was measured for the two ferns. The criticalwater potential at which stomata closed was found to be highin each case; 0.75 MPa and 0.5 MPa respectively.The components of water potential were estimated with the pressurechamber as functions of relative water content. For each speciescell sap was found to be dilute, pressure potential low at fullturgor, and the change in relative water content between fullturgor and wilting point small. Small values of solute potentialat full turgor were also found for the ferns and E. velutinausing a vapour pressure osmometer. Values of the bulk modulusof elasticity of the leaf tissue for each species lay withinthe range of published data. The significance of these resultsfor the epiphytic way of life is discussed. Key words: Water potential, Epiphytes, Diffusive resistance, Orchid, Fern 相似文献
7.
8.
Eleven species of larval digeneans are reported for the firsttime in the UK from the freshwater snail Lymnaea (Radix) auricularia.The latter replaced its congener L. peregra in a gravel pitnear Wraysbury, Berkshire in the Lower Thames Valley and hostedan assemblage of larval digeneans similar to that previouslytransmitted by L peregra. The larval digeneans of L. peregrain small bodies of water in the area were also similar to thosefound in L. auriculania in the gravel pit. This replacementin the role of the host is explained on the basis of morphological,physiological and ecological similarities of the two lymnaeidspecies. (Received 19 February 1992; accepted 27 April 1992) 相似文献
9.
Kathryn A. Coates 《Hydrobiologia》1984,115(1):45-50
The structure of the penial bulb and male efferent duct system of Grania species may be used in addition to setal pattern and spermathecal shape to distinguish species. Six penial bulb types are distinguished: (1) a simple, small, glandular bulb surrounding the male pore; (2) a small, glandular bulb, with a large, associated, dorso-medial gland mass; (3) a small glandular bulb, medial to the male pore, with an elongate male bursa (the aglandular sac), the vas deferens exitting directly into the invaginated male pore; (4) a glandular bulb with an aglandular sac and a small, cuticular stylet embedded in the bulb, extending from the ectal end of the vas deferens; (5) a glandular bulb and an aglandular sac with a long stylet extending from the vas deferens, through the bulb into the sac; and (6) glandular bulb reduced or absent, with or without an aglandular sac; with a long stylet and other prominent modifications, usually muscular, of the vas deferens. The details of the male duct structure were consistent within specimens grouped on the basis of setal distribution and shape and detailed spermathecal structure. Diverse male duct patterns are found within the polytypic species G. macrochaeta and G. postclitellochaeta. The positions of the spermathecal and male pores in their respective segments are distinctive for some species. 相似文献
10.
A new species of copepod belonging to the family Aetideidae,Bradyidius slyliformis sp. nov. is described and figured. Therelationship of this species to the other 12 members of thegenus is discussed.
1Present address: 121 Jalan Athinahapan Dua, Taman Tun Dr Ismail,60000 Kuala Lumpur, Malaysia 相似文献
11.
Shell morphological characters and allozyme electrophoresis were used to study the relationships among six geographical populations
of land snails collected from Peninsular Malaysia. Allozyme electrophoresis was used to study the genetic variations to complement
the morphological features studied that included shell lengths, numbers of whorls and shell colour. Ten loci coding for six
enzymes (MDH, LAP, ALP, PGM, G6P DH, and EST) could be reliably scored in samples from the six populations studied. The dendrogram showed two major clusters with one
cluster comprising Subulinidae populations from Perak, Selangor, Johor, Terengganu, and Pahang while the other cluster included
only the Streptaxidae Huttonella bicolor (red) population. The Subulinidae populations were grouped into two subclusters: one subcluster included the Subulina sp. populations from Perak, Selangor, and Johor, while the other subcluster included the Opeas sp. populations from Terengganu and Pahang. Morphological features can identify the different families ant therefore they
can complement the allozyme genetic studies on the land snail populations. Like other reports in the literature, our results
also underline the importance of a genetic approach in conjunction with a morphological approach, for discriminating land
snail species. The present results suggest that small land snails, which were similar in colour but different in sizes, were
not of the same family/genus.
The text was submitted by the authors in English. 相似文献
12.
Gracilacus wuae n. sp. from soil associated with cow parsnip in Ontario, Canada is described and illustrated. Morphologically, females have a long stylet ranging from 80 to 93 µm long, the lip region not offset from the body contour, without lateral lips but with large and flat submedian lobes, the mouth opening slit-like elongated laterally and surrounded by lateral flaps, the excretory pore is anterior to the knobs of the stylet; males without stylet and the pharynx degenerated. The fourth-stage juveniles lack a stylet, the pharynx degenerated, and can be differentiated into preadult females and males based on the position of the genital primordia. The third-stage juveniles are similar to females but smaller. Phylogenetic studies using the rDNA small subunit 18S, large subunit 28S D2/D3, and internal transcribed spacer (ITS) sequences collectively provide evidence of a grouping with other Gracilacus and some species of Paratylenchus with stylet length of females longer than 41 µm deposited in GenBank. 相似文献
13.
TWO NEW SPECIES OF THE GENUS ISLAMIA RADOMAN, 1973 FROM ITALIAN ISLANDS (PROSOBRANCHIA, HYDROBIIDAE)
BODON MARCO; MANGANELLI GIUSEPPE; SPARACIO IGNAZIO; GIUSTI FOLCO 《Journal of Molluscan Studies》1995,61(1):43-54
Two new Italian species of the genus Islamia (Prosobranchia:Hydrobiidae), one living in eastern Sicily (I. cianensis), andone on Elba Island (Tuscan Archipelago, Italy) (I. gaiteri)are described. The two species are distinguished on the basisof shell and anatomical characters, mainly those of the malegenitalia. I. cianesis n. sp. is characterized by a valvatoidshell and a penial lobe with internal band of glandular tissuenot distinct in its lower portion from the penis body but bulgingapically as a small knob. I. gaiteri n. sp. is characterizedby a planispiral shell and a small lateral penial lobe withoutinternal glandular tissue. (Received 20 December 1993; accepted 27 June 1994) 相似文献
14.
Termites from the genus Odontotermes are known to contain numerous species complexes that are difficult to tell apart morphologically or with mitochondrial DNA sequences. We developed markers for one such cryptic species complex, that is, Odontotermes srinakarinensis sp. nov. from Maxwell Hill Forest Reserve (Perak, Malaysia), and characterised them using a sample of 41 termite workers from three voucher samples from the same area. We then genotyped 150 termite individuals from 23 voucher samples/colonies of this species complex from several sites in Peninsular Malaysia. We analysed their population by constructing dendograms from the proportion of shared-alleles between individuals and genetic distances between colonies; additionally, we examined the Bayesian clustering pattern of their genotype data. All methods of analysis indicated that there were two distinct clusters within our data set. After the morphologies of specimens from each cluster were reexamined, we were able to separate the two species morphologically and found that a single diagnostic character found on the mandibles of its soldiers could be used to separate the two species quite accurately. The additional species in the clade was identified as Odontotermes denticulatus after it was matched to type specimens at the NHM London and Cambridge Museum of Zoology. 相似文献
15.
Twelve new species of Polycystididae Graff, 1905 are described from the Australian east coast. Nine of them could not be placed
in any of the existing genera, and therefore six new genera are erected. Alchoides n. gen. differs from all other polycystidid genera by the presence of a bundle of glands that opens into the distal part
of the male atrium (accessory vesicle type V). Two species are included in the genus, A. alchoides n. sp. and A. dittmannae n. sp., which differ from each other in the shape of the stylet. Ametochus gehrkei n. gen n. sp. can be distinguished from other polycystidids by the presence of a prostate vesicle type III associated with
a prostate stylet type III, combined with the presence of an accessory stylet type III, while a prostate stylet type II is
lacking. Typical for Arrawarria inexpectata n. gen n. sp. is the combined presence of an armed cirrus with a prostate vesicle type II connected to a prostate stylet
type II. Two species are assigned to the new genus Duplexostylus n. gen.: D. rowei n. sp. and D. winsori n. sp. These two species have two unique features: a prostate vesicle type IV directly connected to a prostate stylet type
III and an asymmetrical septum that surrounds the proximal part of the male atrium. They can be distinguished from each other
by differences in the detailed construction of their stylets. Two new species are placed in the new genus Stradorhynchus n. gen.: S. caecus n. sp. and S. terminalis n. sp. They have unpaired gonads and a prostate vesicle type IV connected to a prostate stylet type IV, which combination
of characters makes them unique within the Polycystididae. The two species differ from each other in the shape and size of
the stylet. Triaustrorhynchus armatus n. gen., n. sp. is the first species of the Polycystididae to have three types of stylet in the male atrium: a prostate stylet
type II, a prostate stylet type III and an accessory stylet type III. Three new species could be placed in existing genera:
Cincturorhynchus monaculeus n. sp., Paraustrorhynchus caligatus n. sp. and Polycystis australis n. sp. All three differ from their congeners in the form and dimensions of their stylets. All newly described species are
discussed, giving their similarities and differences with resembling species. Austrorhynchus hawaiiensis Karling, 1977 is reported for the first time in Australia, and the Australian population is compared with populations from
other regions. The presence of Gyratrix hermaphroditus Ehrenberg, 1831, one new species of Paulodora Marcus, 1948 and a new genus of Typhlopolycystidinae Evdonin, 1977 is mentioned. 相似文献
16.
A new ovoviviparous littorinid gastropod, Tectarius (Echininiopsis)niuensis, from Niue, west of the Cook Islands, is described.This is distinguished from the only other ovoviviparous memberof the genus, T. (E.) viviparus (Rosewater, 1982) from the MarianaIslands, here redescribed in detail. The new species is remarkabletor its high-level habitat in the littoral fringe on wave-exposedkarstic limestone cliffs, for its variation in shell shape accordingto tidal level, shell colour polymorphism, calcified operculumand penis with a single mamilliform penial gland. In a cladisticanalysis of morphological characters, including single representativesof each of the three other subgenera of Tectarius (Tectarius,Echininus, Tectininus), these two ovoviviparous species appearas sister-taxa. This is confirmed by a molecular phylogeneticanalysis of the same species, based on the sequence of a portionof the 16S ribosomal RNA mitochondrial gene. Neither analysisunequivocally confirms the monophyly of Tectarius. The divergenceof DNA sequences within Tectarius suggests that the genus arosein the Upper Cretaceous, much earlier than the oldest (UpperEocene) fossils. Only 4 of the 175 species of Littorinidae areknown to be ovoviviparous (with brooding through metamorphosis)and the possible adaptive significance of this type of developmentis discussed. Hitherto, its rarity had been explained by earlyextinction of poorly-dispersed brooding taxa. However, ovoviviparitymay have persisted in Echininiopsis for at least 35 millionyears, and has not precluded colonization of islands 6300kmapart. (Received 17 September 1996; accepted 15 November 1996) 相似文献
17.
A detailed study of the gonads of two endangered species of
thegenus Margaritifera living in the Iberian Peninsula, Margaritiferaauricularia (Spengler, 1793) and Margaritifera
margaritifera(Linnaeus 1758), based on macroscopic and histological
observationsis presented. In both species, gonadal tissue occurs
withinthe visceral mass without a specific location. In hermaphrodite
specimens,male and female acini are mixed in the visceral mass but
canbe clearly distinguished by detailed macroscopic study. The
gonadaltopography and cycle of Margaritifera auricularia is described
forthe first time, indicating that the species is a female
hermaphroditeand that gametogenesis occurs from December to
March. Fiftypercent of Margaritifera margaritifera specimens studied
werehermaphrodites and 50% females. (Received 6 March 2000; accepted 5 June 2000) 相似文献
18.
A new species of eledonid octopus is described from the
southwesternAtlantic Ocean from depths between 90 and 1000 m off the
coastsof southern Brazil, Uruguay, and Argentina. This species,
Graneledoneyamana is characterized by having a papillose skin, two
welldeveloped 'horns' above the eyes, small gills with 5-7 lamellaeon
the outer demibranch, arms with uniserial suckers, 35-80on females
and 26-70 on males. The third right arm is hectocotylized,the ligula
is small, the calamus is large and well differentiated.Ink sac
absent. These characters differ from all other knownGraneledone
species from the southern oceans. (Received 22 July 1999; accepted 20 May 2000) 相似文献
19.
The morphology of the mature spermatozoa of the closely-relatedfreshwater pulmonates, Bulinus africanus and Bulinus globosus,was examined using scanning and transmission electron microscopy.A comparison showed no useful differences that could be usedto distinguish the species though they did differ in one respectfrom Bulinus tropicus, the only other bulinid for which spermmorphology is known. (Received 12 August 1996; accepted 6 December 1996) 相似文献
20.
Three species of Palaeoneilo Hall & Whitfield, namely P.belaeensis Cox, P. indicus Cox and P. rajnathi n. sp., are describedfrom the Jurassic rocks of Habo Hill in Kutch. The right, valveof belaeensis has been discovered. Its previous record fromthe Bathonian (Middle Jurassic) appears to be erroneous. Bothbelaeensis and indicus were unknown from the present area. (Received 11 November 1983; 相似文献