Paryphanta busbyi
Encyclopedia
Paryphanta busbyi is a species
of large predatory land snail
, a terrestrial
pulmonate gastropod mollusk in the family
Rhytididae
.
, New Zealand: Kaitaia
, Hokianga
, Mangonui, Bay of Islands
, Otonga East, Mania Hill, Whangarei
, Brynderwyn Range
, Hen Island
, Woodcocks
and Warkworth
, where is its souther native distribution. Localitions with introduced distribution include Little Huia in Waitakere Ranges
, Waiuku
in Awhitu Peninsula and Kaimai Ranges
.
Its distribution is coincident in range with the kauri forest.
The type locality is New Zealand. The type specimen is stored in Natural History Museum, London.
is large, broadly umbilicated, depressed and subdiscoidal. The shell is opaque and shining. The colour is deep green, usually with some radial streaks of blackish-green.
There is a sculpture
on the nucleus containing oblique and arcuate radial plaits. The succeeding two whorls are distinctly rugose. On the post-embryonic whorls more or less distinct spiral cords appear, which are first directed upwards, but become spiral on the last whorl. Plaits are distant, low, broadly rounded, varying in number from about 5 to 10 and absent on the base. There are retractive distant growth-plications,
which are prominently and closely plicate at the suture. The whole surface of the shell is microscopically decussated by exceedingly fine and dense radiate and spiral lines, the latter slightly wavy. The periostracum
is thick, glabrous, shining, overhanging the peristome. The spire
is flat, very little raised and broadly convex. The protoconch
has 2 whorls, flatly convex, the volutions rather rapidly increasing. The shell has 4½ whorls
, that are rapidly increasing. The last whorl is very large, slightly convex, periphery and base rounded, the body-whorl more or less deflexed anteriorly. Suture well impressed.
The aperture
is within shining-blue. Aperture obliquely lunate-oval. Peristome is simple, inflexed throughout. The columella is very oblique, slightly arcuate, and shortly reflexed above. Umbilicus broad, perspective and deep.
The width of the shell is 60–79 mm. The height of the shell is 33–44 mm. The width of the type specimen is 66 × 53 mm, the height of the shell is 29 mm.
The shell
of Paryphanta busbyi has very thick periostracum
and only few micrometre thick calcium
layer. When the shell is kept in dry environment, the shell will explode into pieces, because its periostracum shrinks.
The embryonic shell globose, flat above, of 2 whorls, narrowed toward the base and narrowly umbilicate. The width of the shell is 10 mm. The height of the shell is 9 mm.
has a sharp even margin, and a deeply incised line or groove rather less than 2 mm from the edge. On the underside of the mantle is the usual prominent lappet which conceals the respiratory and anal pores, and in addition to this is a long narrow fold on the left side.
The retractor muscles: The buccal mass and pedal retractors are fused together posteriorly where they unite with the columella of the shell. The buccal retractor rests dorsally on the pedal muscles, and forms a broad powerful band. The pedal retractors are continuously attached to the foot, and there are no free progressively attached pedal retractors as in genus Helix. The ocular retractors branch from the pedal muscles; they bifurcate towards their anterior ends, and supply the inferior tentacle retractors.
The length of the radula is about an inch, and 0.4 inch in width at the anterior end, tapering to a point posteriorly, with about 104 transverse rows of denticles (tiny teeth). The rows of denticles are forming an obtuse angle of about 130°, salient posteriorly. There is about 100 small denticles in each row, that described and figured by Captain Frederick Wollaston Hutton
with formula 50-0-50, while Robert C. Murdoch
gave the formula 52-0-52. Hutton described them like this: Denticles are all aculeate, and similar, with simple bevelled tips. The first five lateral denticles are small. From the sixth they gradually increase in length to about the thirty-fifth, and then get smaller. Murdoch described them like this: A few of the innermost denticles, usually not more than two on each side, are small and very slender. Occasionally one of these slender spicula-like denticles is somewhat separated from the adjoining denticle, and where this occurs it gives to the row the appearance of a central denticle. There is no jaw.
The digestive system
contains enormous buccal mass is and muscular development. Its posterior end is curved down and forward, and a powerful ventral muscle firmly binds it to the more anterior cylindrical portion. The retractor muscle envelopes the posterior end, and from the anterior portion of the mass proceed a number of ventro-lateral muscles, which unite with the immediately adjoining body-walls. The oesophagus enters the buccal cavity dorsally in the anterior fourth. The salivary gland
s are situate upon the posterior half of the buccal mass; they are fused together in the median line and partly envelope the oesophagus. From the anterior end of each gland proceeds a small salivary duct
, which enters the buccal cavity a little below the œsophageal opening. The stomach forms a simple elongated sac, and the tract of the intestine does not appear to differ from Powelliphanta hochstetteri
.
The kidney is shortly tongue-shaped, in length less than twice its breadth, about half the length of the lung, and about one and a half times the length of the pericardium
; the latter has the usual position on the left margin of the kidney. The ureter
continues around the right margin of the kidney, follows the posterior limit of the lung, and opens close to the intestine. From this point the intestine, or rectum, forms a long straight tube. There is a well-marked ridge on the pulmonary wall less than 3 mm. from the side of the rectum, and the narrow area thus defined appears to be the open continuation of the ureter. The above-mentioned ridge examined in section proves to be tubular; it continues into the tissue of the mantle, and appears to unite with the blood-sinus contained therein. The venation of the lung, with the exception of the great pulmonary vein
, is very indistinct. This vein runs direct to the auricle, is of considerable breadth, and has an undulating, almost convolute, appearance. On approaching the pneumostome
it forms several branches, and the latter, with their accompanying afferent vessels, are fairly well indicated. The vessels on the rectal side of the lung are minute and very much branched, while on the cardiac side only a few traces may be seen.
The suprapedal gland
opens between the head and foot immediately below the mouth; it forms a long flattish structure, much folded and lying on the floor of the body cavity. Its posterior end is slightly enlarged, and enclosed in a cavity in the foot, to which it has a muscular attachment. From the termination of the gland the usual tube or duct proceeds through the substance of the foot, but does not form a caudal mucous pit
.
The reproductive system
anatomically differs from genera Powelliphanta
and Wainuia
. There is remarkable extreme reduction of male organs in Paryphanta busbyi and the absence of receptaculum seminis (spermatheca). This is resemblance with Schizoglossa novoseelandica. There is a blunt, somewhat triangular, projection of the vaginal wall, with a retractor muscle proceeding to the adjoining body-wall; this is the only evidence of the male organs before any of the surrounding tissue has been dissected away. On removing this outer tissue a small loop is seen to project from the vaginal wall. This is the posterior termination of the penis, which passes into the vas deferens without any perceptible change, except a slight diminution of the tube. The anterior portion of the vagina forms a wide chamber, closed posteriorly by a valve-like papillar structure; the interior walls are slightly darkish in colour, and weakly longitudinally plicated. The papilla is continuously united with the vaginal wall, and the perforation through its centre is the only communication with the oviduct. Its anterior third projects freely into the anterior vaginal chamber. Its walls are comparatively thick; internally they are lightly longitudinally plicated, and have a whitish epitheloid lining.
The penis opens into the posterior portion of the papillar structure in the form of a small tube; it proceeds through the thick vaginal wall in an oblique anterior direction, and becomes slightly enlarged or bulbous towards its termination. The vas deferens, as previously stated, is free to a very limited extent, and is imbedded in the vaginal wall. Its posterior prostatic course through the prominent folds or plications of the oviduct is tubular, thence open, but for a short distance enfolded on all sides by the above-mentioned plications. From this point to the albumen gland it is a well-marked area of a rusty brownish tint, and somewhat separated from the uteral portion by the longitudinal folds. The uterus is thrown into numerous sacculations, and its interior walls are richly convolutely plicated. There is no indication of a receptaculum seminis. The albumen gland is very large, a usual feature in this group of animals; in outline it is roughly boot-shaped. The hermaphrodite duct enters near the base of the albumen gland; it is a simple straight tube, with several short lesser tubes branching from it and uniting with the several masses which form the hermaphrodite gland. The latter are closely convoluted structures and imbedded in the liver.
When compared with Schizoglossa novoseelandica it is found that the vas deferens in the latter species is free to a greater extent, that no portion of its internal prostatic course appears to be tubular, and there does not appear to be any vaginal papilla. During copulation the atrium is everted; the penis pore is thus brought forward and may be detected on the everted wall. In Paryphanta busbyi the anterior vaginal chamber doubtless undergoes complete eversion, and the vaginal papilla will be thrust outwards to a considerable degree—probably to a much greater extent than the appearance of the organ in its present condition suggests.
, among plants on the ground and under logs in kauri forests and in shrubland
. They are also found in shrublands with non-native species like Hedychium
and in forests with non-native plants including plantations of Pinus radiata.
Paryphanta busbyi is active when the weather is cool and wet. In dry weather it is inactive.
Paryphanta busbyi is carnivorous and predatory, feeding on earthworm
s, insects, insect larvae, snails of the genus Rhytida
and on its own species (cannibalism
).
This snail sometimes lives in trees, very likely in clusters of semiparasitic plants, where it may find its natural food, earthworms.
It takes 7 years to grow to the size where the width of the shell is 54 mm.
The population density
of Paryphanta busbyi is low in comparison of Powelliphanta.
Predators of Paryphanta busbyi include rat
s, pig
s, possum
s, hedgehogs and birds. Rats and birds eat the juvenile snails. Pigs eat these snails at all sizes including the eggs, and pigs also destroy the snail's habitat.
noted in 1913, that this species is being rapidly exterminated by the destruction of its natural habitat - (the kauri forests), by bush-fires, and by rats and pigs. Threats of this species are consuming by introduced animals, habitat fragmentation
and habitat modification.
It is protected by Wildlife Act 1953
.
Paryphanta spp. was listed in appendix II of CITES and it was removed, because collection is not a significant factor of this species (and the genus) decline.
This species is nearly threatened in the 2009 IUCN Red List
.
It was listed as in category "Chronically Threatened - Gradual decline" in 2002 New Zealand Threat Classification System
lists, and was classified in category C ("third priority of threatened species") according to the Molloy & Davis 1994 ranking system. However it is not in this category in the 2005 New Zealand Threat Classification System lists.
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of large predatory land snail
Snail
Snail is a common name applied to most of the members of the molluscan class Gastropoda that have coiled shells in the adult stage. When the word is used in its most general sense, it includes sea snails, land snails and freshwater snails. The word snail without any qualifier is however more often...
, a terrestrial
Terrestrial animal
Terrestrial animals are animals that live predominantly or entirely on land , as compared with aquatic animals, which live predominantly or entirely in the water , or amphibians, which rely on a combination of aquatic and terrestrial habitats...
pulmonate gastropod mollusk in the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Rhytididae
Rhytididae
Rhytididae is a taxonomic family of medium-sized predatory air-breathing land snails, carnivorous terrestrial pulmonate gastropod molluscs in the superfamily Rhytidoidea.This family has no subfamilies.-Anatomy:...
.
Distribution
The distribution of Paryphanta busbyi includes the Northern parts of North IslandNorth Island
The North Island is one of the two main islands of New Zealand, separated from the much less populous South Island by Cook Strait. The island is in area, making it the world's 14th-largest island...
, New Zealand: Kaitaia
Kaitaia
Kaitaia is a town in the far north region of New Zealand, at the base of the Aupouri Peninsula which is about 160 km northwest of Whangarei. It is the last major settlement on the main road north to the capes and bays on the peninsula...
, Hokianga
Hokianga
Hokianga is an area surrounding the Hokianga Harbour, also known as The Hokianga River, a long estuarine drowned valley on the west coast in the north of the North Island of New Zealand....
, Mangonui, Bay of Islands
Bay of Islands
The Bay of Islands is an area in the Northland Region of the North Island of New Zealand. Located 60 km north-west of Whangarei, it is close to the northern tip of the country....
, Otonga East, Mania Hill, Whangarei
Whangarei
Whangarei, pronounced , is the northernmost city in New Zealand and the regional capital of Northland Region. Although commonly classified as a city, it is officially part of the Whangarei District, administered by the Whangarei District Council a local body created in 1989 to administer both the...
, Brynderwyn Range
Brynderwyn Range
The Brynderwyn Range or Brynderwyn Hills is a ridge extending east-west across the Northland Peninsula in northern New Zealand some 60 kilometres south of Whangarei, from the southern end of Bream Bay in the east to the Otamatea River in the west...
, Hen Island
Hen and Chicken Islands
The Hen and Chickens Islands lie to the east of the North Auckland Peninsula off the coast of northern New Zealand. They are located to the east of Bream Head and southeast of Whangarei....
, Woodcocks
Woodcocks
Woodcocks is a locality 15 km west of Warkworth in the Rodney District of New Zealand. It was named in honour of the Woodcock family who settled there around 1895....
and Warkworth
Warkworth
Warkworth may refer to:*Warkworth, Northamptonshire, England*Warkworth, Northumberland, England* Warkworth Castle* Warkworth Hermitage*Warkworth, Ontario, Canada*Warkworth, New South Wales, Australia*Warkworth, New Zealand*John Warkworth...
, where is its souther native distribution. Localitions with introduced distribution include Little Huia in Waitakere Ranges
Waitakere Ranges
The Waitakere Ranges are a chain of hills in the Auckland metropolitan area, generally running approximately 25 km from north to south, 25 km west of central Auckland, New Zealand. The maximum elevation within the ranges is 474 m...
, Waiuku
Waiuku
Waiuku is a country town in the Franklin District, in the North Island of New Zealand. It is located at the southern end of the Waiuku River, which is an estuarial arm of the Manukau Harbour...
in Awhitu Peninsula and Kaimai Ranges
Kaimai Ranges
The Kaimai Range is a mountain range in the North Island of New Zealand. It is part of a series of ranges, with the Coromandel Range to the north and the Mamaku Ranges to the south. The Kaimai Range separates the Waikato in the west from the Bay of Plenty in the east.The highest point of the range...
.
Its distribution is coincident in range with the kauri forest.
The type locality is New Zealand. The type specimen is stored in Natural History Museum, London.
Shell description
The shellGastropod shell
The gastropod shell is a shell which is part of the body of a gastropod or snail, one kind of mollusc. The gastropod shell is an external skeleton or exoskeleton, which serves not only for muscle attachment, but also for protection from predators and from mechanical damage...
is large, broadly umbilicated, depressed and subdiscoidal. The shell is opaque and shining. The colour is deep green, usually with some radial streaks of blackish-green.
There is a sculpture
Sculpture (mollusc)
The sculpture of a mollusc shell is the three-dimensional ornamentation on the outer surface, as distinct from the basic shape of the shell itself or colouration. Sculpture may be concave as well as convex. Sometimes it has microscopic detail. Sculpture refers to the calcareous outer layer, not the...
on the nucleus containing oblique and arcuate radial plaits. The succeeding two whorls are distinctly rugose. On the post-embryonic whorls more or less distinct spiral cords appear, which are first directed upwards, but become spiral on the last whorl. Plaits are distant, low, broadly rounded, varying in number from about 5 to 10 and absent on the base. There are retractive distant growth-plications,
which are prominently and closely plicate at the suture. The whole surface of the shell is microscopically decussated by exceedingly fine and dense radiate and spiral lines, the latter slightly wavy. The periostracum
Periostracum
The periostracum is a thin organic coating or "skin" which is the outermost layer of the shell of many shelled animals, including mollusks and brachiopods. Among mollusks it is primarily seen in snails and clams, i.e. in bivalves and gastropods, but it is also found in cephalopods such as the...
is thick, glabrous, shining, overhanging the peristome. The spire
Spire (mollusc)
A spire is a descriptive term for part of the coiled shell of mollusks. The word is a convenient aid in describing shells, but it does not refer to a very precise part of shell anatomy: the spire consists of all of the whorls except for the body whorl...
is flat, very little raised and broadly convex. The protoconch
Protoconch
A protoconch is an embryonic or larval shell of some classes of molluscs, e.g., the initial chamber of an ammonite or the larval shell of a gastropod...
has 2 whorls, flatly convex, the volutions rather rapidly increasing. The shell has 4½ whorls
Whorl (mollusc)
A whorl is a single, complete 360° revolution or turn in the spiral growth of a mollusc shell. A spiral configuration of the shell is found in of numerous gastropods, but it is also found in shelled cephalopods including Nautilus, Spirula and the large extinct subclass of cephalopods known as the...
, that are rapidly increasing. The last whorl is very large, slightly convex, periphery and base rounded, the body-whorl more or less deflexed anteriorly. Suture well impressed.
The aperture
Aperture (mollusc)
The aperture is an opening in certain kinds of mollusc shells: it is the main opening of the shell, where part of the body of the animal emerges for locomotion, feeding, etc....
is within shining-blue. Aperture obliquely lunate-oval. Peristome is simple, inflexed throughout. The columella is very oblique, slightly arcuate, and shortly reflexed above. Umbilicus broad, perspective and deep.
The width of the shell is 60–79 mm. The height of the shell is 33–44 mm. The width of the type specimen is 66 × 53 mm, the height of the shell is 29 mm.
 |
 |
The shell
Gastropod shell
The gastropod shell is a shell which is part of the body of a gastropod or snail, one kind of mollusc. The gastropod shell is an external skeleton or exoskeleton, which serves not only for muscle attachment, but also for protection from predators and from mechanical damage...
of Paryphanta busbyi has very thick periostracum
Periostracum
The periostracum is a thin organic coating or "skin" which is the outermost layer of the shell of many shelled animals, including mollusks and brachiopods. Among mollusks it is primarily seen in snails and clams, i.e. in bivalves and gastropods, but it is also found in cephalopods such as the...
and only few micrometre thick calcium
Calcium
Calcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...
layer. When the shell is kept in dry environment, the shell will explode into pieces, because its periostracum shrinks.
The embryonic shell globose, flat above, of 2 whorls, narrowed toward the base and narrowly umbilicate. The width of the shell is 10 mm. The height of the shell is 9 mm.
Anatomy
The animal is bluish-black, with the foot-sole perhaps a shade lighter in colour. On the head and neck are a few regular rows of rugae, somewhat quadrate in outline; on other parts of the body the rugae appear to be oval-shaped, irregular in size, and not forming continuous rows. The mantleMantle (mollusc)
The mantle is a significant part of the anatomy of molluscs: it is the dorsal body wall which covers the visceral mass and usually protrudes in the form of flaps well beyond the visceral mass itself.In many, but by no means all, species of molluscs, the epidermis of the mantle secretes...
has a sharp even margin, and a deeply incised line or groove rather less than 2 mm from the edge. On the underside of the mantle is the usual prominent lappet which conceals the respiratory and anal pores, and in addition to this is a long narrow fold on the left side.
The retractor muscles: The buccal mass and pedal retractors are fused together posteriorly where they unite with the columella of the shell. The buccal retractor rests dorsally on the pedal muscles, and forms a broad powerful band. The pedal retractors are continuously attached to the foot, and there are no free progressively attached pedal retractors as in genus Helix. The ocular retractors branch from the pedal muscles; they bifurcate towards their anterior ends, and supply the inferior tentacle retractors.
The length of the radula is about an inch, and 0.4 inch in width at the anterior end, tapering to a point posteriorly, with about 104 transverse rows of denticles (tiny teeth). The rows of denticles are forming an obtuse angle of about 130°, salient posteriorly. There is about 100 small denticles in each row, that described and figured by Captain Frederick Wollaston Hutton
Frederick Wollaston Hutton
Captain Frederick Wollaston Hutton, FRS, was an English scientist who applied the theory of natural selection to explain the origins and nature of the natural history of New Zealand.- Biography :...
with formula 50-0-50, while Robert C. Murdoch
Robert C. Murdoch
Robert C. Murdoch was a malacologist in New Zealand.- Biography :He received a secondary-school education, and afterwards travelled widely with Captain Shuttleworth, of Wanganui. He spent some years subsequent to 1888 in farming near Wanganui, but in 1892 he went to Sydney and studied Mollusca...
gave the formula 52-0-52. Hutton described them like this: Denticles are all aculeate, and similar, with simple bevelled tips. The first five lateral denticles are small. From the sixth they gradually increase in length to about the thirty-fifth, and then get smaller. Murdoch described them like this: A few of the innermost denticles, usually not more than two on each side, are small and very slender. Occasionally one of these slender spicula-like denticles is somewhat separated from the adjoining denticle, and where this occurs it gives to the row the appearance of a central denticle. There is no jaw.
The digestive system
Digestive system of gastropods
The digestive system of gastropods has evolved to suit almost every kind of diet and feeding behavior. Gastropods as the largest taxonomic class of the mollusca are very diverse indeed: the group includes carnivores, herbivores, scavengers, filter feeders, and even parasites.In particular, the...
contains enormous buccal mass is and muscular development. Its posterior end is curved down and forward, and a powerful ventral muscle firmly binds it to the more anterior cylindrical portion. The retractor muscle envelopes the posterior end, and from the anterior portion of the mass proceed a number of ventro-lateral muscles, which unite with the immediately adjoining body-walls. The oesophagus enters the buccal cavity dorsally in the anterior fourth. The salivary gland
Salivary gland
The salivary glands in mammals are exocrine glands, glands with ducts, that produce saliva. They also secrete amylase, an enzyme that breaks down starch into maltose...
s are situate upon the posterior half of the buccal mass; they are fused together in the median line and partly envelope the oesophagus. From the anterior end of each gland proceeds a small salivary duct
Salivary duct
Salivary duct may refer to:* Parotid duct* Submaxillary duct* Major sublingual duct...
, which enters the buccal cavity a little below the œsophageal opening. The stomach forms a simple elongated sac, and the tract of the intestine does not appear to differ from Powelliphanta hochstetteri
Powelliphanta hochstetteri
Powelliphanta hochstetteri, known as one of the amber snails, is a species of large, carnivorous land snail, a terrestrial pulmonate gastropod mollusc in the family Rhytididae.-Distribution:...
.
The kidney is shortly tongue-shaped, in length less than twice its breadth, about half the length of the lung, and about one and a half times the length of the pericardium
Pericardium
The pericardium is a double-walled sac that contains the heart and the roots of the great vessels.-Layers:...
; the latter has the usual position on the left margin of the kidney. The ureter
Ureter
In human anatomy, the ureters are muscular tubes that propel urine from the kidneys to the urinary bladder. In the adult, the ureters are usually long and ~3-4 mm in diameter....
continues around the right margin of the kidney, follows the posterior limit of the lung, and opens close to the intestine. From this point the intestine, or rectum, forms a long straight tube. There is a well-marked ridge on the pulmonary wall less than 3 mm. from the side of the rectum, and the narrow area thus defined appears to be the open continuation of the ureter. The above-mentioned ridge examined in section proves to be tubular; it continues into the tissue of the mantle, and appears to unite with the blood-sinus contained therein. The venation of the lung, with the exception of the great pulmonary vein
Pulmonary vein
The pulmonary veins are large blood vessels that carry blood from the lungs to the left atrium of the heart. In humans there are four pulmonary veins, two from each lung...
, is very indistinct. This vein runs direct to the auricle, is of considerable breadth, and has an undulating, almost convolute, appearance. On approaching the pneumostome
Pneumostome
The pneumostome is a feature of the external body anatomy of an air-breathing land slug or land snail. It is a part of the respiratory system of gastropods....
it forms several branches, and the latter, with their accompanying afferent vessels, are fairly well indicated. The vessels on the rectal side of the lung are minute and very much branched, while on the cardiac side only a few traces may be seen.
The suprapedal gland
Suprapedal gland
The suprapedal gland or mucous pedal gland is an anatomical feature found in some snails and slugs. It is a gland located inside the front end of the foot of gastropods.The term suprapedal means "above the foot"....
opens between the head and foot immediately below the mouth; it forms a long flattish structure, much folded and lying on the floor of the body cavity. Its posterior end is slightly enlarged, and enclosed in a cavity in the foot, to which it has a muscular attachment. From the termination of the gland the usual tube or duct proceeds through the substance of the foot, but does not form a caudal mucous pit
Caudal mucous pit
The caudal mucous pit, or caudal mucous horn, is an anatomical structure on the tail end of the foot of various land snails and slugs, terrestrial pulmonate gastropod mollusks....
.
The reproductive system
Reproductive system of gastropods
The reproductive system of gastropods varies greatly from one group to another within this very large and diverse taxonomic class of animals...
anatomically differs from genera Powelliphanta
Powelliphanta
Powelliphanta, common name amber snails, is a genus of large, carnivorous land snails, terrestrial pulmonate gastropod molluscs. As a group their survival status is endangered.- Taxonomy :...
and Wainuia
Wainuia
Wainuia is a genus of air-breathing predatory land snails, terrestrial pulmonate gastropod molluscs in the family Rhytididae.-Species:Species within the genus Wainuia include:* Wainuia clarki , North Island...
. There is remarkable extreme reduction of male organs in Paryphanta busbyi and the absence of receptaculum seminis (spermatheca). This is resemblance with Schizoglossa novoseelandica. There is a blunt, somewhat triangular, projection of the vaginal wall, with a retractor muscle proceeding to the adjoining body-wall; this is the only evidence of the male organs before any of the surrounding tissue has been dissected away. On removing this outer tissue a small loop is seen to project from the vaginal wall. This is the posterior termination of the penis, which passes into the vas deferens without any perceptible change, except a slight diminution of the tube. The anterior portion of the vagina forms a wide chamber, closed posteriorly by a valve-like papillar structure; the interior walls are slightly darkish in colour, and weakly longitudinally plicated. The papilla is continuously united with the vaginal wall, and the perforation through its centre is the only communication with the oviduct. Its anterior third projects freely into the anterior vaginal chamber. Its walls are comparatively thick; internally they are lightly longitudinally plicated, and have a whitish epitheloid lining.
The penis opens into the posterior portion of the papillar structure in the form of a small tube; it proceeds through the thick vaginal wall in an oblique anterior direction, and becomes slightly enlarged or bulbous towards its termination. The vas deferens, as previously stated, is free to a very limited extent, and is imbedded in the vaginal wall. Its posterior prostatic course through the prominent folds or plications of the oviduct is tubular, thence open, but for a short distance enfolded on all sides by the above-mentioned plications. From this point to the albumen gland it is a well-marked area of a rusty brownish tint, and somewhat separated from the uteral portion by the longitudinal folds. The uterus is thrown into numerous sacculations, and its interior walls are richly convolutely plicated. There is no indication of a receptaculum seminis. The albumen gland is very large, a usual feature in this group of animals; in outline it is roughly boot-shaped. The hermaphrodite duct enters near the base of the albumen gland; it is a simple straight tube, with several short lesser tubes branching from it and uniting with the several masses which form the hermaphrodite gland. The latter are closely convoluted structures and imbedded in the liver.
When compared with Schizoglossa novoseelandica it is found that the vas deferens in the latter species is free to a greater extent, that no portion of its internal prostatic course appears to be tubular, and there does not appear to be any vaginal papilla. During copulation the atrium is everted; the penis pore is thus brought forward and may be detected on the everted wall. In Paryphanta busbyi the anterior vaginal chamber doubtless undergoes complete eversion, and the vaginal papilla will be thrust outwards to a considerable degree—probably to a much greater extent than the appearance of the organ in its present condition suggests.
Ecology
These large snails live in litterLitter
Litter consists of waste products such as containers, papers, wrappers or faeces which have been disposed of without consent. Litter can also be used as a verb...
, among plants on the ground and under logs in kauri forests and in shrubland
Shrubland
Shrubland, scrubland, scrub or brush is a plant community characterized by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity...
. They are also found in shrublands with non-native species like Hedychium
Hedychium
Hedychium is a genus of perennial plants native to tropical Asia and the Himalayas, commonly growing to between 120 and 180 cm tall. Common names include garland flower, ginger lily, and kahili ginger...
and in forests with non-native plants including plantations of Pinus radiata.
Paryphanta busbyi is active when the weather is cool and wet. In dry weather it is inactive.
Paryphanta busbyi is carnivorous and predatory, feeding on earthworm
Earthworm
Earthworm is the common name for the largest members of Oligochaeta in the phylum Annelida. In classical systems they were placed in the order Opisthopora, on the basis of the male pores opening posterior to the female pores, even though the internal male segments are anterior to the female...
s, insects, insect larvae, snails of the genus Rhytida
Rhytida
Rhytida is a genus of small to medium-large, air-breathing, predatory land snails, terrestrial pulmonate gastropod molluscs in the family Rhytididae.This is the type genus of the family.- Distribution :This genus is endemic to New Zealand-Species:...
and on its own species (cannibalism
Cannibalism (zoology)
In zoology, cannibalism is the act of one individual of a species consuming all or part of another individual of the same species as food. Cannibalism is a common ecological interaction in the animal kingdom and has been recorded for more than 1500 species...
).
This snail sometimes lives in trees, very likely in clusters of semiparasitic plants, where it may find its natural food, earthworms.
Life cycle
The eggs are usually laid at the foot of large trees in clusters of four to six eggs, underneath dead leaves. The shape of the eggs is oval and seldom constant in dimensions and ranges from 10.5 × 9.5 mm or 12 × 9 mm to 14 × 10.75 mm. It has white limy egg without cuticle.It takes 7 years to grow to the size where the width of the shell is 54 mm.
The population density
Population density
Population density is a measurement of population per unit area or unit volume. It is frequently applied to living organisms, and particularly to humans...
of Paryphanta busbyi is low in comparison of Powelliphanta.
Predators
These snails were not eaten by the Māori people.Predators of Paryphanta busbyi include rat
Rat
Rats are various medium-sized, long-tailed rodents of the superfamily Muroidea. "True rats" are members of the genus Rattus, the most important of which to humans are the black rat, Rattus rattus, and the brown rat, Rattus norvegicus...
s, pig
Pig
A pig is any of the animals in the genus Sus, within the Suidae family of even-toed ungulates. Pigs include the domestic pig, its ancestor the wild boar, and several other wild relatives...
s, possum
Possum
A possum is any of about 70 small to medium-sized arboreal marsupial species native to Australia, New Guinea, and Sulawesi .Possums are quadrupedal diprotodont marsupials with long tails...
s, hedgehogs and birds. Rats and birds eat the juvenile snails. Pigs eat these snails at all sizes including the eggs, and pigs also destroy the snail's habitat.
Conservation
Already Henry SuterHenry Suter
Henry Suter was a New Zealand zoologist, naturalist, palaeontologist, and malacologist.- Biography :...
noted in 1913, that this species is being rapidly exterminated by the destruction of its natural habitat - (the kauri forests), by bush-fires, and by rats and pigs. Threats of this species are consuming by introduced animals, habitat fragmentation
Habitat fragmentation
Habitat fragmentation as the name implies, describes the emergence of discontinuities in an organism's preferred environment , causing population fragmentation...
and habitat modification.
It is protected by Wildlife Act 1953
Wildlife Act 1953
-External links:*...
.
Paryphanta spp. was listed in appendix II of CITES and it was removed, because collection is not a significant factor of this species (and the genus) decline.
This species is nearly threatened in the 2009 IUCN Red List
IUCN Red List
The IUCN Red List of Threatened Species , founded in 1963, is the world's most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature is the world's main authority on the conservation status of species...
.
It was listed as in category "Chronically Threatened - Gradual decline" in 2002 New Zealand Threat Classification System
New Zealand Threat Classification System
The New Zealand Threat Classification System is used by the Department of Conservation to assess conservation priorities of species in New Zealand....
lists, and was classified in category C ("third priority of threatened species") according to the Molloy & Davis 1994 ranking system. However it is not in this category in the 2005 New Zealand Threat Classification System lists.
Further reading
- Coad N. (1998) "The kauri snail (Paryphanta busbyi busbyi), its ecology and the impact of introduced predators". MSc thesis, University of Auckland. 161 pp.
- Cox J. C.James Charles CoxJames Charles Cox was an Australian physician and conchologist.Cox was born at Mulgoa, southwest of Sydney where he played with Aboriginal children and leared from them about native birds and animals. He was educated at the local parish school and the King's School, Parramatta...
(1888) "Contributions to Conchology. No. I." Proceedings of the Linnean Society of New South Wales 2(4): 1061-1064. Linnean Society of New South Wales. Plate XX, figure 6. - Hutton F. W.Frederick Wollaston HuttonCaptain Frederick Wollaston Hutton, FRS, was an English scientist who applied the theory of natural selection to explain the origins and nature of the natural history of New Zealand.- Biography :...
(1880) Manual of the New Zealand Mollusca. A systematic and descriptive catalogue of the marine and land shells, and of the soft mollusks and Polyzoa of New Zealand and the adjacent islands. Wellington. Pages 21-22. - Ohms P. G. (1948) "Some aspects of the anatomy of Paryphanta busbyi". MSc thesis, University of Auckland.
- Powell A. W. B.Arthur William Baden PowellDr Arthur William Baden Powell CBE was a New Zealand malacologist, naturalist and palaeontologist, a major influence in the study and classification of New Zealand molluscs through much of the twentieth century. He was known to his friends and family by his third name, "Baden".Powell was born at...
(1979) New Zealand Mollusca. William Collins Publishers Ltd, Auckland, New Zealand, ISBN 0-00-216906-1 - Spencer H. G., Brook F. J., Kennedy M. (March 2006) "Phylogeography of Kauri Snails and their allies from Northland, New Zealand (Mollusca: Gastropoda: Rhytididae: Paryphantinae)". Molecular Phylogenetics and EvolutionMolecular Phylogenetics and EvolutionMolecular Phylogenetics and Evolution is a peer-reviewed scientific journal of evolutionary biology and phylogenetics. The journal is edited by D.E. Wildman.-Indexing:The journal is indexed in:*EMBiology*Journal Citation Reports*Scopus*Web of Science...
38(3): 835-842. ,
External links
- http://www.doc.govt.nz/conservation/native-animals/invertebrates/kauri-snail/
- http://bushmansfriend.blogspot.com/2007/07/kauri-snails-paryphanta-busbyi-mating.html
- photo of feeding
- photo of shells
- Paryphanta busbyi at National Center for Biotechnology InformationNational Center for Biotechnology InformationThe National Center for Biotechnology Information is part of the United States National Library of Medicine , a branch of the National Institutes of Health. The NCBI is located in Bethesda, Maryland and was founded in 1988 through legislation sponsored by Senator Claude Pepper...
(NCBI)