The genus Bostryx in central western Argentina: anatomical and distributional description of four of its southernmost species (Gastropoda, Bulimulidae)

ABSTRACT The genus Bostryx Troschel, 1847 is endemic to South America, extending from Ecuador to Chile and Argentina. The southernmost Argentinian species of the genus that inhabit San Luis, San Juan and Mendoza provinces, specially the pre-Andes, Andes and Sierras Pampeanas mountain ranges, were examined. This is the first time the anatomy of Bostryx pastorei (Holmberg, 1912), Bostryx reedi (Parodiz, 1947) and Bostryx strobeli (Parodiz, 1956) has been described.Bostryx cordillerae (Strobel, 1874) is re-described regarding shell and anatomy due to new morphological data. The main differences among the species examined are based on shell characters. The distribution ofBostryx mendozanus (Strobel, 1874) and Bostryx cuyanus (Pfeiffer, 1867), other species found in this region, was also discussed.

Ueber den begriff "Kinoplasma" in der spermiogenese von Australorbis Glabratus Olivaceus (Mollusca, Pulmonata, Planorbidae)

Zur Klaerung der Frage, ob der Begriff "Kinoplasma" fuer gewisse, von MERTON (1924,1926, 1930) beobachtete Bildungen an den reifenden Spermiden von pulmonaten Mollusken oder fuer Bestandteile des Cytoplasmas im Sinne von STRASBURGER und SCARTH zu verwenden ist, werden in der vorliegenden Mitteilung die Vorgaenge bei der Spermiohistogenese von Australorbis glabratus olivaceus untersucht. Es ergibt sich: 1. Das von MERTON bezeichnete "Kinoplasma" existiert nicht als solches, es handelt sich bei den von ihm dargestellten Protoplasmabildungen um kugelige, von den Spermiden abgeschnuerte Restkoerper nicht verwendeten Baumaterials, bestehend aus Protoplasma und einigen Mitochondrien. Sie werden von den Naehr- oder Bazalzellen phagozytiert. Der Ausdruck "Kinoplasma" kann nur fuer die submikroskopischen, geformten, faedigen Elemente des Cytoplasmas reserviert bleiben, die den geradlinigen Fall der uebrigen nicht geformten Komponenten bremst oder ablenkt; damit muss das Kinoplasma aber aus dem Begriff des Cytoplasmas herausgenommen werden, da es, wenn auch vermutlich reversibel, eine Differenzierung darstellt. 2. Der Spermienfaden wird von den Centriolen (Axialfilament) und den Mitochondrien (zwei peripher gelegene Spiralfilamente), sowie einem Plasmamantel gebildet. 3. Nach Beendigung des Auswachsens der Spermiengeissel, die zu diesem Zeitpunkt nur aus dem Achsenfaden und dem Protoplasmazylinder besteht, setzt sich eine Protoplasmamasse vom Kopf in Richtung zum Geisselende in Bewegung. Sie fuehrt den Golgi-Koerper und sehr viele Mitochondrien mit sich. Aus diesen entwickeln sich Fibrillen, die sich zu den beiden Spiralfilamenten zusammenfuegen. Diese Masse entspricht der von MERTON in seiner Theorie als Kinoplasma bezeichneten Komponente. 4. Die Bewegung dieses Protoplasmateils wird auf den Schub zurueckgefuehrt, den die sich bildenden Fibrillen auf die Mitochondrien ausueben. 5. Die Rueckwaertsbewegung dieses Protoplasmakoerpers beruht wahrscheinlich auf Elastizitaet und Kontraktilitaet des Plasmalemmas. 6. Das zum Kopf zurueckgekehrte Protoplasma wird mit restlichen Mitochondrien als Kugel ausgeschieden und von den Naehrzellen phagocytiert. 7. Der Golgi-Koerper wird vor Beendigung der Protoplasmawanderung bereits in der letzten Haelfte der Geissel eliminiert.

Ueber die formveraenderungen des golgiapparates waehrend der spermiogenese von Australorbis glabratus olivaceus: (Mollusca, Pulmonata, Planorbidae)

Im ersten Teil der vorliegenden Arbeit werden die cytogenese und Histogenese der Spermien von australorbis glabratus olivaceus beschrieben, waehrend im zweiten Teil auf die Formveraenderungen des Golgiapparates des Naeheren eigegangen wird. Es wurden angewandt: Phasenkontrast, Halbdunkelfeld und Dunkelfeld; Vitalfaerbungen mit Janusgruen und Neutralrot; als histologische Faerbung nach Osmiumfixierung erwies sich Eisenhaematoxylin als guenstig, nach Sublimatfixierung zum histologischen Naschwei der chromophoben Substanz des Golgiapparates ergab die Azanfaerbung mit Nachfaerbung in Lichtgruen die besten Ergebnisse. Die Cytogenese zeigt bis zum Erreichen der Spermiden keine Besonderheiten im Vergleich mit anderen shon bearbeiteten Mollusken. Die Histogenese zeit jedoch einige bemerkenswerte Punkte, die von den bereits bekannten Befunden an anderen Mollusken erheblich abwichen. Die Kernmembran der Spermide bildet durch Schrumpfung in Folge Kondensierung des Chromatins eine Spiralfalte auf der Kernoberflaeche mit ueber 2 Um gaengen. Das proximale Centriol ist geteilt, ein Teil bildet eine Fusskappe des Kerns, von der ein Faden ausgeht, der das ganze Kerninnere durchzieht. Der andere Teil bildet den Axialfaden und dient beiden Spiralfilamenten als Lager. Das distale Centriol bildet eine umgekehrte Glocke, an deren Rand sich die Spiralfaeden und in deren Innerem sich der Axial faden anheften; es setzt sich distalwaerts in den nackten Schwanzfaden fort. Der Golgiapparat ist vom primordialen Spermiogonium bis zur reifenden Spermide durch alle Entwicklungs- und Teilungsstadien zu verfolgen. Er besteht in der Spermiocyte aus der chromophoben Masse und 12 Dictyosome, die sich dieser auflagern, sowie aus 4 Proacroblasten. Diese 16 Kondrete trennen sich vor der Diakinese und jedes wandert fuer sich zu einem der Spindelpole. Die Praespermide besitzt 6 Dictyosome und 2 Proacroblasten, die sich zu 3 Diatyosome und 1 Proacroblast auf die Spermide verteilen. Der leztere Koerper wandelt sich zum Acroblast um, der sich als Acrosom dem apikalen Kernpol auflegt.

Biomphalaria occidentalis sp.n. from South America (Mollusca basommatophora pulmonata)

A new species of South American planorbid snail, Biomphalaria occidentalis, is described. It is indistinguishable from B. tenagophila (Orbigny, 1835), by the characteristics of the shell and of most organs of the genital system. In B. tenagophila there is a pouch on the ventral wall of the vagina (Fig. 4A, vp), absent in B. occidentalis (Fig. 3A), and on the ventral wall of the vagina (Fig. 4A, vp), absent in B. occidentalis (Fig. 3A), and the prepuce is much wider than the penial sheath, its width increasing distalward (Fig. 4, ps,pp), whereas in B. occidentalis the prepuce is wider than the penial sheath but keeps about the same width all along (Fig.3, ps, pp). The two species are biologically separate by absolute reproductive isolation. The geographical distribution of B. occidentalis is shown in Fig. 14. So far it has been found in the Brazilian states of Acre, Amazonas (?), Mato Grosso, Mato Grosso do Sul and Paraná, and in Paraguay. Its type-locality is Campo Grande, state of Mato Grosso do sul, where it was collected from several biotopes related to affluents of the Aquiduana river, chiefly Córrego Prosa and Córrego Ceroula. Specimens were deposited in the following malacological collections: Instituto Oswaldo Cruz, Rio de Janeiro; Academy of Natural Sciences, Philadelphia; Museum of Zoology, University of Michigan; and British Museum (Natural History).

Nonhemocyte sources of selected lysosomal enzymes in Biomphalaria glabrata, B. tenagophila and B. straminea (Mollusca: Pulmonata)

The specific activities of acid phosphatase, alkaline phosphatase, β-glucuronidase, lysozymes, glutamate-oxalacetate transaminase and glutamate-pyruvate transaminate were determined in the head-foot and digestive gland of Brazilian Biomphalaria glabrata (Touros), B. tenagophila (Caçapava) and B. straminea (Monsenhor Gil). All six enzymes were detected inthe 3000g supernatant. Both cytoplasmic enzymes, glutamate-oxalacetate and glutamate-pyruvate transaminase exhibited the highest specific activities. In the case of the four hydrolytic enzymes assayed, β-glucuronidase exhibited the highest specific activity while lysozyme showed the lowest activity. All six enzymes are thought to be produced by cells within the head-foot and digestive gland of B. glabrata, B. tenagophila and B. straminea.

Lymnaea rupestris sp. n. from Southern Brazil (Pulmonata: Lymnaeidae)

A new species of South American lymnaeid snail, Lymnaea rupestris, is described. So far it has been found only in its type-locality, Nova TeuTõnia, a village in the municipality of Seara (27° 07' S, 52° 17' W), state of Santa Catarina, Brazil. It is distinguishable, by characteristics of the shell and internal organs, from the other two lymnaeid species known to occur in the area, Lymnaea columella and L. viatrix. Its shell has 4 markedly shouldered whorls, deep suture, ovoid or rounded aperture occupying about half the length of the shell, and reaches about 6 mm in length in adults; in columella and viatrix the shell has 4-5 rounded whorls, shallow suture, and reaches over 10 mm in adults; the aperture is ovoid, occupying about half the length of the shell in viatrix, about two thirds in columella. Anatomically it is readily separated from L. columella by the shape of the ureter, straight in rupestris, with a double flexure in columella. Comparison with L. viatrix shows the following main differences: distalmost portion of the oviduct with a low, caplike lateral swelling in rupestris, with a well-developed pouch in viatrix; uterus bent abruptly caudalward in rupestris, only slightly curved rightward in viatrix; basal half of the spermathecal duct hidden by the prostate in rupestris, wholly visible or nearly so in viatrix; spermiduct sinuous and uniformly wide in rupestris, straight and gradually narrowing in viatrix; prostate more than half as long and nearly as wide as the nidamental gland, and with a slit-like lumen in cross-section in rupestris, less than half as long as and much narrower than the nidamental gland, and with an inward fold in cross-section in viatrix; penial sheath about as long and as wide as the prepuce in rupesris, shorter and narrower than the prepuce in viatrix. An important ecological characteristic of L. rupestris is its habitat on wet rocks most often outside bodies of water, although in close proximity to them. Specimens were deposited in the following malacological collections: Instituto OswaldoCruz, Rio de Janeiro; Academy of Natural Sciences, Philadelphia; Museum of Zoology, University of Michigan; and British Museum (Natural History).

Lymnaea Diaphana; a study of Topotypic specimens (Pulmonata: Lymnaeidae)

A description of the species Lymnaea diaphana King, 1830 is presented, on the basis of material collected at its type-locality, San Gregorio, on the north coast of the Strait of Magellan, in the Chilean province of Magallanes. It may be identified by the following characters taken together: adult shell over 10 mm in length, whorls inflated, regularly convex, separated by a well-marked suture, aperture ovate occupying about half the shell length; renal organ forming an approximately right angle with the ureter; pouch of the oviduct well noticeable high on the right ventral surface and on the right side of the nidamental gland; uterus bent to the right into an approximately right angle; body of the spermatheca projected into the pulmonary cavity and adhered to the pericardium and to the roof of the pulmonary cavity; spermiduct highly sinuous, folding dorsalward between the left half of the oviduct and the left shoulder of the nidamental gland, and then winding on ventralward to reach the prostate on the middle line; prostate voluminous, convex on the left, pushed in on the right, with a deep dorsal furrow corresponding to a fold which projects into the prostatic lumen and is more developed at the fore half of the organ; apical end of the penial sheath with about six minute protuberances corresponding to inner chambers; prepuce from about as long about twice as long as the penial sheath, with some variation beyond those limits; lateral teeth of the radula basically tricuspid, with a usually simple ectocone which may show a bifid or trifid point. A diagnosis between lymnaea diaphana and three other lymnaeids which also occur in South America and were previously studied by the author - L. columella, L. viatrix and L. rupestris - is presented.

Biomphalaria Tenagophila Guaibensis ssp. n. from Southern Brazil and Uruguay (pulmonata: Planorbidae). I. Morphology

A new subspecies of planorbid snail, biomphalaria tenagophila guaibensis, is described. It has been found along the coastal belt of the Brazilian state of rio grande do Sul and the middle part of Uruguay, from Porto Alegre to Mercedes. It differs from the nominate subspecies, Biomphalaria tenagophila tenagophila, in the appearance of the penial complex (prepuce longer and proportionally slenderer in B. t. guaibensis, shorter and proportionally stouter in b. t. tenagophila), in the ratio between the lengths of the penial sheath and the prepuce, in the ratio between the lengths of the uterine complex and the penial complex, and in a coefficient of difference of 2.44 for the ratio between the penis sheath and prepuce and of 2.02 for the ratio between the uterine complex and penial complex. The shell and the other organs of the genital system are similar in both subspecies. B. t. guaibensis is very similar to Biomphalaria occidentalis Paraense, 1981, but is readily separated from it by the presence of a vaginal pouch, which is lacking in the latter, besides showing highly significant difference in the penis sheath: prepuce and uterine complex: penial complex ratios. Crossbreeding experiments which lend additional support to the recognition of B. t. guaibensis as a subspecies will be reported elsewhere.

Biomphalaria intermedia in Mato Grosso do Sul, Brazil, and Misiones, Argentina (Pulmonata: Planorbidae)

The occurrence of Biomphalaria intermedia (Paraense & Deslandes, 1962) is recorded at Três Lagoas and Dourados (state of Mato Grosso do Sul, Brazil), and Parque Nacional Iguazú (province of Misiones, Argentina), west and southwest, respectively, of its known western limit, in the state of São Paulo. The species was also found at Parapuã, a new locality to São Paulo state.

Consumo quantitativo e qualitativo de Perifíton colonizado em substrato artificial Biomphalaria Tenagophila (Gastropoda, Planorbidae)

Moluscos criados no campo em gaiolas transparentes e escurecidas apresentaram o mesmo consumo diário de perifíron; entretanto nas primeiras existia maior proporção de organismos vegetais e nas últimas maior proporção de organismos animais. O consumo diário por molusco foi significamente maior em presença de maiores quantidades de alimento, porém a proporção consumida do total de alimento disponível decresceu.

Physa Marmorata Guilding, 1828 (Pulmonata: Physidae)

A description of Physa marmorata Guilding, 1828, based on material collected at its type-locality, the Caribbean island of Saint Vincent, is presented. The shell is thin, horn-colored, surface very glossy, diaphanous. Spire acute, elevated; protoconch distinct, rounded-conical, reddish-brown; five not shouldered, broadly convex whorls with subobsolete spiral lines and thin growth lines. Aperture elongated, 1.4-2.0 times as long as the remaining shell length, narrow obovate-lunate; upper half acute-angled,lower half oval,narrowly rounded at the base, outer lip sharp, inner lip completely closing the umbilical region; a very distinct callus on the parietal wall; columellar lip with a low ridge gradually merging into the callus. ratios: shell width/shell length = 0.44 - 0.52 (mean 0.47); spire length /shell lenght = 0.33-0.41 (mean 0.39); aperture length/shell lenght = 0.59-0.67 (mean 0.62). Oral lappets laterally mucronate, foot spatulate with deeply pigmented acuminate tail. Mantle reflection with 6-10 short triangular dentations covering nearly half the right surface of the body whorl, and 4-6 covering a part of the ventral wall. Body surface with tiny dots of greenish-yellow pigment besides melanin. Renal tube tightly folded in toa zigzag course. Ovotestis diverticula acinous, laterally pressed against each other around a collecting canal. Ovispermiduct with well-developed seminal vesicle. oviduct highly convoluted, merging into a less convoluted nidamental gland which narrows to a funnel-shaped uterus and a short vagina. Spermathecal body oblong, more or less constricted in the middle and somewhat curved; spermathecal duct uniformly narrow, a little longer than be body. About 20 prostatic diverticula, simple, bifurcate or divided into a few short branches, distalmost ones assembled into a cluster. Penis long, nearly uniformly narrow; penial canal with lateral opening about the junction of its middle and lower thirds. Penial sheath with a bulbous terminal expasion the tip of which isinserted into the caudal end of the prepuce. Prepuce shouldered, much wider than the narrow portion of the penial sheath. Penial sheath/prepuce ratio about 2.08 (1.45-2.75). The main extrinsic muscles of the penial complex are a retractor, with a branch attached to the bulb, and another to the caudal end of the penial sheath; and a protractor, with a branch attached to the shoulder of the prepuce and adjoining area of the penial sheath, and another to the caudal end of the penial sheath. Egg capsule C-shaped, with 10-30 elliptical eggs (snails 10mm long) measuring about 1.10 mm (0.90-1.32) through the long axis and surrounded by an inner and an outer lamellate membranes. Jaw a simple obtusely V-shaped plate. radula will be described separately.

Physa cubensis Pfeiffer, 1839 (Pulmonata: Physidae)

A description of Physa cubensis Pfeiffer, 1839, based on 15 speciments collected in Havana, Cuba, is presented. The shell, measuring 9.0 x 4,8mm to 12.3 x 6.4mm, is ovate-oblong, thin, diaphanous, horncolored, shining. Spire elevated, broadly conical; protoconch distinct, roundish, reddish-brown. About five moderately shouldered, roundly convex whorls, penultimate whorl expanded; spiral striation subobsolete; growth line faint on the intermediate whorls, clearly visible on the body whorl, crowded here and there. Suture well impressed. Aperture elongated 2.05 - 2.67 (mean 2.27) times as long as the remaining length of the shell, narrow obovulate-lunate; upper half acute-angled, lower half oval, narrowly rounded at the base; outer lip sharp, inner lip completely closing the umbilical region; a thick callus on the parietal wall; columellar plait well marked. Ratios: shell width/shell length - 0.52-0.61 (mean 0.55); spire length/shell length = 0.27 - 0.33 (mean 0.31); aperture length/shell length = 0.67 - 0.73 (mean 0.69). Oral lappets laterally mucronate; foot spatulate with acuminate tail. Mantle relection with 6 - 8 short triangular dentations in the right lobe (columellar side) and 4 - 6 in the left lobe (near the pneumostome). Renal tube tightly folded into a zigzag course. Ovotestis, ovispermiduct, seminal vesicle, oviduct, nidamental gland, uterus and vagina as in Physa marmorata (see Paraense, 1986, Mem. Inst. Oswaldo Cruz, 81: 459-469). Spermathecal body egg-shaped or pear-shaped; spermathecal ducta uniformly narrow with expanded base, a little longer than the body. Spermiduct, prostate and vas deferens as in P. marmorata (Paraense, loc. cit.). Penis wide proximally, narrowing gradually apicad; penial canal with subterminal outlet. Penial sheath following the width of the penis and ending up by a bulbous expansion somewhat narrower than the proximal portion. Penaial sheath/prepuce ration = 1,25 - 1,83 (mean 1.49). Prepuce much wider than the bulb of the penial shealth, moderately shouldered owing to the intromission of the bulb, and with a large gland in one side of its proximal half occupating about a third of its length. Extrinsic muscles of the penial complex as in P. marmorata. Jaw a simple obtusely V-shaped plate. Radula to be described separetely.

Genetical exchanges between one Biomphalaria glabrata (Gastropoda: Planorbidae) and a varying number of partners

When one pigmented Biomphalaria glabrata is mated with 1 to 20 albino snails, the percentage of albino parent producing pigmented offspring decreases while the percentage of parent laying albino offspring increases. If the number of snaisl/group increases, the mean duration of the use of allosperm decreases.

Duration of pairing and use of allosperm in Biomphalaria glabrata (Gastropoda: Planorbidae)

Virgin homozygous black pigmented and albino Biomphalaria glabrata are paired during a period varying from 1 to 20 days. The rate of cross-fertilized parents is statistically similar for the various lengths of pairing. As a whole, nearly 80% of the albino snails produce a pigmented progeny. This production begins as soon as the snails are mated and continues after their separation. To measure the actual use of the allosperm, its use during the postmating period must be added to the length of mating. So, it appears that the real use of the allosperm is statistically constant (mean slightly inferior to 8 weeks) and not related to the length of the previous pairing.

Prosobrânquios terrestres do Brasil: Cyclophoridae: Neocyclotus (N. ) agassizi (Bartsch & Morrison, 1942) (Mollusca, Gastropoda, Mesogastropoda)

Studies on specimens from Brazil (States of Pernambuco and Alagoas) were carried out in order to relate data about morphology of hard and soft parts o Nocyclotus (N.) agassizi (Bartsh & Morrison, 1942).