Norfolk Island
Robert V J P Varman Ph D
Double click underlined names for the illustrations or you can cheat and go straight to the snail gallery. Don't forget to click the beautiful unnamed species (family Rytididae?) at the end of this list and email me if you have any comments.
REFERENCES
BEESLEY, P.L., ROSS, G.J.B. & WELLS, A. (eds) (1998). MOLLUSCA: THE SOUTHERN SYNTHESIS. FAUNA OF AUSTRALIA. VOL 5. CSIRO PUBLISHING: MELBOURNE, PARTS A AND B.
IREDALE, TOM. THE LAND MOLLUSCA OF NORFOLK ISLAND. THE AUSTRALIAN ZOOLOGIST. VOL 11, PART 1. JUNE 11, 1945.
IREDALE, TOM. A COMPARISON OF THE LAND MOLLUSCAN FAUNAS OF THE KERMADEC GROUP AND NORFOLK ISLAND. TRANSACTIONS NEW ZEALAND INSTITUTE. VOL 47. 1915.
PRESTON, H.B. CHARACTERS OF NEW GENERA AND SPECIES OF TERRESTRIAL MOLLUSCA FROM NORFOLK ISLAND. ANNALS AND MAGAZINE OF NATURAL HISTORY. SER. 8, VOL XII. December 1913.
SMITH, B.J. (1992). NON-MARINE MOLLUSCA. IN HOUSTON, W.W.K. (ed). ZOOLOGICAL CATALOGUE OF AUSTRALIA. CANBERRA: AGPS VOL 8.
SYKES, E.R. NOTES ON THE NON-MARINE MOLLUSCA OF NORFOLK AND PHILLIP ISLANDS, WITH DESCRIPTIONS OF NEW SPECIES. PROCEEDINGS OF THE MALACOLOGICAL SOCIETY. VOL IV. Read 8th June, 1900.
Introduction
The following has been reworked in the light of B.J. Smith's Non-Marine Mollusca so that the relationships of the species to those elsewhere may be better understood. Smith noted that the snail faunas of Norfolk and Lord Howe Islands are in need of revision, so I hope that this is a step in the right direction. Smith had to accept the decisions of previous workers at face value, except in the few cases where he was able to examine types and good original documentation to make taxonomic decisions for synonymy (for which there is plenty of scope).
For the vast majority of Norfolk Island species, taxonomy was based on shell features only. The early workers were over-zealous in naming species and subspecies where there may only have been one. An example of this over-zealousness is illustrated by the mistaking of the introduced zonitid Hawaiia miniscula (Binney, 1840) as indigenous; shells found were divided into two genera containing four species. Smith has corrected this but was obliged to place two of the species in 'Incertae sedis' because 'status and whereabouts unknown, presumed lost'.
The reliance on previous documentation has meant that one marine species, Dendrolamellaria mathewsi (Preston 1913), is still listed as a terrestrial species. The ecological designation, 'saxicoline; under rocks' is another case of inherited misinformation. Confusion exists in some of the species where, I suspect, juveniles were elevated to species, even genera. Other anomalies are pointed out under the various sections listed below. It must have been tempting for B.J.Smith to exclude Norfolk and Lord Howe Islands from his 1992 work, I am grateful to him that he did not.
A visit to Norfolk Island in 1997 gave me the opportunity to review species, species distribution and fossiliferous deposits containing shells. The visit allowed me to expand on and correct previous studies I made during the 1980s to 1997.
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FAMILY: ASSIMINIDAE (Omphalotropinea)
GENUS: Omphalotropis (Pfeiffer, 1851)
SUBGENUS: Omphalotropis (Duritropus) Iredale, 1944
B.J.Smith (1992) is responsible for this subgeneric arrangement.
Omphalotropis (Duritropis) brenchleyi (Sykes, 1900) (Species 1)
Lightly sculpted above the carination, smooth and often flattened below the carination line. There are great variations in some populations, from near-smooth to very sculptured, banded to mono-coloured. See discussion below.
GENERAL: Duritropis is found in a great range of colours and bands of colour. The colours include deep red, pink, yellow, orange and browns of all shades and intensity. Some white or colourless examples are also to be found. Sometimes the colouration is restricted to the top or to the base of the shell. The bands, where they exist, are clear or of a brown colour, sometimes both. There may be one, two or even three bands but mostly just one. Some specimens are highly sculpted with vertical ribs, with or without carination (so can be rounded in profile or angled). Some have strong sculpture below the keel, as seen in some of the fossiliferous deposits. The ostensibly smooth examples generally have traces of slight sculpture. The smooth examples tend to be larger and the sculpted ones smaller--as if there was only so much shell bulk available! There are many intermediate types. Duritropis feeds on moist or wet leaf litter, dead bark and bark at the base of trees (only when wet). A good time to see them in action is during a period of light rain.
The Palaeo deposit specimens are noticeably larger on average than those of the later fossiliferous deposits and those living at present. What made the individuals of the present population shrink?
Localized Coastal Varieties
There is a localized population at Lot 112d near the entrance to the road to the Cook Memorial which are uncommonly large, uncommonly smooth and rounded, and mono coloured, typically red or yellow with highlight colour patches on the last whorl. On shell characteristics, these fit better as Species 3 but they do not live on the bark of trees.
Nearby is another population (overlap) of a highly sculpted type with outstanding ribs and keeling, with a secondary keeling below seen on the last whorl. Strong ribbing below the keel (which is unusual in the coastal varieties but very like some of the Palaeo examples). They typically have "slipped" sutures along the whorl. Most are colourless or perhaps brown.
A few very isolated populations are to be found at Kingston, some confined to a single old pine tree (always a tree that represented a remnant of former forest). A small variety of a deep red-brown to amber brown colour. The Bataille variety has a double clear band and is without outstanding ribs; the Cemetery Bay variety has medium outstanding ribs but only on the upper side of the whorl, smooth on the underside, like the Ball Bay series. Found with coloured double band or without (some shells were old). These have a very outstanding keel (last whorl).
Ball Bay series (north-east direction from Kingston). These small varieties are very like the Cemetery Bay remnants with sculpted upper halves and smooth below with strong keeling but generally have a single red-brown coloured band just below the suture. Most are colourless or brown but nearly all the ones I've seen have unusually coloured apex whorls, red, red-brown, yellow brown--probably a reminder or remnant of a former greater variety of colour in the population. These marginalized populations have become smaller and dull coloured through predation selection I would guess. A Garnet Point (next to Ball Bay) example has two coloured bands.
Hundred Acre Series. These show the greatest variety of types: medium to large, sculpted to smooth, (if sculpted, it's on the upper whorl), keeled to rounded, coloured and clear bands with astonishing combinations, some are mono-coloured, bright yellow, red-orange or red and a few are bi-coloured (over-developed colour band?).
NOTE: What were named in Iredale (1945) as Duritropis fortilirata, Duritropis albocarinata and Telmosena cerea have been placed in incertae sedis by Smith (1992). In my view these names should be scrapped because of the lack of documentation and confusion with non-Norfolk Island species.
Omphalotropis (Duritropis) species 2
An easily recognized, squat heavily sculpted snail, the ribs are so outstanding that they appear like castilations at the suture area. The operculum is very deeply set during aestivation. These are found on the rich muddy surface loam and leaf litter found in the rain forest. During dry weather the loam dries into crispy lumps with the shell often incorporated. Seem to be confined to the upper slopes of Mounts Pitt, Bates and Cross. These are most definitely smaller than the other Duritropis types.
Omphalotropis (Duritropis) species 3
A very smooth shell without carination and lightly impressed sutures. These are to be found on wet or dry tree trunks, though usually not higher up than about a metre or two. I checked these again in 1997 and confirm that there is no integration of Omphalotropis (Duritropis) snail features, particularly in shell form, as is to be seen on the ground. I did not have time to study these in any detail but hope to on my next visit to the Island. I suspect that these snails are also to be found in leaf litter but should be distinguishable from the more common smooth forms which do integrate with the sculptured forms. In one localized population on the east side of Mount Bates (palm area) only sculptured and smooth forms of Omphalotropis (Duritropis) sp were found, that is without intermediate forms - I interpreted these as being represented by a restricted form of species 1 and by 3. See Telmosena
Note: D. fortilirata, Iredale and Omphalotropis albocarinata (also D. albocarinata) were relegated to Incertae sedis by Smith.
SUBGENUS: Omphalotropis (Duritropus) Iredale, 1944
Omphalotropis (Telmosena) suteri, Sykes, 1900.
Only this species identified. The ultimate prood of validity will rely on the analysis of the animal within the shell.
GENERAL: I had doubted the distinction between Duritropis and Telmosena because of the many intermediate types. Telmosena seems to lack the carination and sculpture of Duritropis, though shares some of the colour and band variations. I have often found specimens on the underside of leaves of certain plants and shrubs such as Macropiper excelsum, Meryta augustifolia, Meryta latifolia and Pennantia endlicheri. Duritropis is generally found under leaves or grazing on old leaves and rotting timber.
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Family DIPLOMMATINIDAE
GENUS: Palmatina Iredale, 1944
Palmatina belli, Preston, 1913
This type appears more squat, bulging out at the sides and is not as high as the others. Found in Palaeo and later fossiliferous deposits--note contrasting P. quintali. Distinct mid axis placing of the aperture.
Palmatina coxi, H Adams, 1868
Live population example seems mid way in features with the other two described here. Slightly off-set placement of the aperture.
Palmatina quintali, Iredale, 1945
Tall thinnish type found in Palaeo and later fossiliferous deposits. Has six or seven whorls and very distinct ribs. The Palaeo examples are noticeably larger than the later fossiliferous and the live examples. The original was found in a live population at Harpers Road--have checked this area and found none).
GENERAL: The live populations are difficult to locate and rare. They seem to like rotting stumps. The great variations found in the Palaeo and later fossiliferous deposits are not found in the live populations. I would suspect that all belong to the same species because of the intermediate types, at most two species or sub-species. The original determinations were based on limited examples but once one has seen several hundred, one begins to wonder if the distinctions of the number and quality of the whorls and ribs or whether the aperture is slightly off-set or not, are important determinations.
These differ from a similar series from Lord Howe Island, the latter have a characteristic depression on the face of the last whorl above the aperture. Out of the hundreds of Norfolk specimens I have examined not one showed this curious feature.
GENUS: Fermepalaina, Iredale, 1945
The two species Palaina nancena (Iredale, 1945) and Palaina pittensis (Iredale, 1945) seem to me to be descriptions of juvenile shells of Palmatina. For instance, as also seen in hundreds of the fossiliferous specimens, the juveniles do not have the trumpet-like apertures of the adults.
B.J. Smith (1992) raised Fermepalaina to genus level and decided that Palaina nancena and Palaina nancena bera were synonyms on the basis of examination of types. Smith did not compare Fermepalaina with Palmatina: I am still of the opinion that Fermepalaina is a synonym of palmatina
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FAMILY: ACHATINELLIDAE
GENUS: Elasmias wakefieldia, Cox 1868
These are found at the east and south-east quarter of coastal Kingston along with populations of Tornelasmias but can be easily distinguished. I suspect that they may have been introduced, as they are rarely found in fossiliferous deposits (contamination?). A very similar species, if not the same, can be found along coastal areas of the Sydney and the Central Coast of New South Wales. Not previously recorded on Norfolk Island.
GENUS: Tornatellinops, Pilsbry and Cooke, 1915
Tornatelliops norfolkensis, Preston, 1913
My live example is from Mount Pitt but answers the description of the original found at Ball Bay. These are very distinctive and uncommon. No juveniles found.
Tornatellinops nepeanense, Preston, 1913
Toothed juveniles. Variations found in an isolated population at Cascade.
Tornatellinops sp.
Apart from the above, there might be several species or varieties involved, some may have been introduced. Some survive in very small isolated clumps of grass or in small pockets of remnant native vegetation.
Note: Tornelasmias (previously Tornatellinops) moohuense, Preston. Shorter and broader. Juveniles have teeth in their apertures, not seen in adults, except soetimes a trace. Some examples from the Palaeo show extraordinary teeth.
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FAMILY: ACHATINELLIDAE? (Drawing No 111)
Tiny shells were found in one location at Ball Bay. The shells, as Tornelasmias and Tornatellinops, are a very shiny brown but darkish. The apex of the shells have a very distinct dull greyish hue. The edge, or lip, of the aperture seems darker with a distinct reddish tinge and has a milky glass-like columella. I have seen nothing like them anywhere else on Norfolk. Not previously recorded?
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FAMILY: SUBULINIDAE
GENUS: Lamellaxis Strebel and Pfeiffer, 1882
SUBGENUS: Lamellaxis (Allopeas) Baker, 1935
Lamellaxis (Allopeas) clavulinus, Potiez and Michaud, 1838
Introduced. 'Large Opeas'. Found in a variety of habitats from exotic contexts to native vegetation but only near disturbed ground. One group found under waterfall ledges. None found in fossiliferous contexts.
Lamellaxis (Allopeas) gracilis, Hutton, 1834
More than likely introduced. Opeas (medium) Found at Lower Garden at Cascade, very rare. Not found in fossiliferous deposits.
GENUS: Eremopeas Pilsbury, 1906
Eremopeas tuckeri, Pfeiffer, 1846
Opeas (Lowland needle, sculptured (Drawing No 168). Introduced. Like Opeas sydneybayensis. Missing in Palaeo and fossiliferous deposits but found in deposits 1788-1790s at the Pier Area, Kingston, or earlier. A live population was found in a minuscule area (isolated rock outcrop) at Kingston.
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FAMILY:
GENUS:
Opeas (Lowland needle, smooth). (No 41)
Five specimens in the Palaeo deposit and others in the 'prehistoric deposit'. Seems like the descriptions of the 'Blind Snail'--Cecilioides acicula (Müller). A very small, elongated, thin, opeas-like shaped shell with a rounded protoconch. Shiny and see-through shell. Very rare live population at Kingston only confined to a rocky outcrop.
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FAMILY: PUPILLIDAE
GENUS: Nesopuparia Pilsbry, 1913
Nesopuparia norfolkensis Sykes, 1900
These are to be found on the bark of large old pines after good soaking rain, possibly feeding off minute fungi. They may also be found on blackish lichen on moist rocks or boulders. These snails are not common but have a wide distribution in native forest. They are rare in fossiliferous deposits, one was found in the Palaeo deposit, again, larger than the average in live populations. The live shell is a rich brown colour with a contrasting white aperture. The teeth are a characteristic feature of this shell, except in juveniles. The teeth and aperture appear to vary from shell to shell and seem to change as the shell gets older. Seven teeth may be traced but some of the smaller teeth are not well expressed. In some mature shells a tiny eighth tooth may be seen at the upper right hand area of the aperture. Not listed in B.J. Smith (1992).
Nesopuparia variety
A race of small Nesopuparia with the same colouring as N. norfolkensis but distinctly smaller and more compact. Specimens collected from the upper Orange Vale area (under Kay Woods): small colony restricted to a few old Norfolk Pines, probably isolated for some 150 years or more due to clearing and grazing. May be due to inbreeding.
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FAMILY: SUCCINEIDAE
GENUS: Succinea Draparnoud, 1801
SUBGENUS: Succinea (Succinea) Draparnoud, 1801
Succinea (Succinea) norfolkensis, Sykes 1900
Now regarded as belonging to the family Succinea. (pers. com. Phil Colman, Australian Museum). Iredale admits two species, one for Norfolk Island and one for Nepean Island However, all S. nepeanensis, Preston, specimens are fossiliferous. From the many hundreds of specimens examined, I find that the largeness and range of special features are not confined to the specimens found on Nepean Island and are well matched among two living populations on Norfolk: the same may be said for the Norfolk fossiliferous deposits. Variations include, extremes in height and width of shell and aperture; distinct keeling in the shell (fossiliferous and a population on Mount Pitt and at Hundred Acre); reduced upper sworls; axis variations; elongation without the usual 'shoulder'; weakly or stronly expressed growth lines. Hence, I feel that only one name is necessary, S. norfolkensis, Sykes, until anatomical studies prove otherwise. B.J. Smith came to the same conclusion.
Spirancinea are one of the more common of Norfolk Island's indigenous snail species and were also common during the time when the fossiliferous deposits were formed at Kingston and off-shore Nepean Island. They undoubtedly thrived on Philip Island once. Curiously they are strikingly uncommon in the Palaeo deposit.
Some live populations can be remarkably distinct; the snails of the coastal areas from Ball Bay to Steele's Point and from Simon's Water to Anson Bay are small with a maximum length of 12mm (the published length for S. norfolkensis!). An isolated population at Hundred Acre most strikingly resembles the range found in the Kingston and Nepean Island fossiliferous deposits; generally being large, up to 17mm long. The longest published length being 14.74mm: I found several at Nepean Island measuring 18mm to 19mm in length. There are also some large size populations in the National Park. The live snail is usually of a dark tan colour but when dead the skin comes off and the shell has a pinkish hue; the shell eventually decalcifies, becomming whiter and thicker.
Spirancinea are to be found among leaf litter, usually out feeding after rain. They are able to survive in areas of secondary native growth as long as there is no grazing. Interestingly, Succineidae are found in Australia (all over the world) with very similar shells but with entirely different habits and breeding cycles, so it is probable that a new genus name will have to be found because it is unlikely that these snails will be found to have a close relationship with the Austalian species.
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FAMILY: PUNCTIDAE
GENUS: Paralaoma Iredale, 1913
I find the distinctions made often unconvincing (four whorls, five whorls) or just confusing. These need reviewing and I strongly suspect that only about one or two names may be found to be valid. The genus is described as "depressedly turbinate shells" (Iredale). The following species as listed by Iredale were not examined or modified by B.J. Smith (1992) so had to admit them as were.
Paralaoma orestias Preston, 1913 (Syn: P. nobbsiana).
Described by Iredale as normal for the genus but finely striate, slightly distant ribs (interstices longitudinally minutely striate) and deep narrow unbilicus. 1mm by 2mm to 2.25mm, 5 whorls.
Paralaoma perminuta Preston, 1913
Described as a little abnormal for the genus. Base concentrically striate and flattened. Rather wide umbilicus. Only, 0.5mm-1.25mm, 4 whorls.
Paralaoma depressior Preston, 1913
More depressed and umbilicus wider and sculpture less marked than P. orestias. Preston regarded the shell esp., sculpture similar to P. perminuta. 0.75mm by 2mm to 2.25mm, 4 1/2 whorls.
Paralaoma duncombei Iredale, 1945
Larger and more elevated, more rounded whorls, periferal sub-keeling obselete, slanting radial riblets, mouth more rounded and wider more open umbilicus. 2.5mm by 1.25mm.
Paralaoma ahena Iredale, 1945
Also not a normal member of the genus, like P. lidgbirdensis of Lord Howe according to Iredale. Whorls convex, impressed suture, more tightly coiled thanb usual. Narrow umbilicus. Apex smooth but adult whorls with fine radial ribs. Circular mouth and straight columella. 2mm by 1mm, 4 whorls.
GENUS: Laomopa Iredale, 1945 (generic name, temporarily located here --Iredale)
Laomopa flavida Iredale, 1945
Miniscule shell, 1mm by 0.6mm. Flattened convex base and narrow umbilicus. Rounded whorls closely coiled. Mouth transversely ear-shaped. Sculpture microscopically striate. 1mm by 0.6mm
GENUS: Christianoconcha quintale Iredale, 1945
Distinguished from Paralaoma by having two parietal lamellae medially placed.
Christianoconcha quintali Iredale, 1945
Apical whorls smooth one and a half whorls. 1.75mm by 1mm.
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FAMILY: CHAROPIDAE
Basically tight coiled and planar.
GENUS: Cryptocharopa Preston, 1913
Cryptocharopa exagitans Cox, 1870
I have found scores of what seems to be this species but have only found traces of the 'agglutinated mass' on a few examles (usually along the perifery of the shell). 3.75mm to 3.25mm by 1.5mm, 5 whorls
GENUS: Norfolcioconcha Preston, 1913 (Genotype: Endodonta norfolkensis)
These are easily distinguished by the two parietal lamellae and two lamellae on the outer wall (as seen at the aperture). Present in the Palaeo and 'Prehistoric' fossiliferous deposits.
Norfolcioconcha norfolkensis Hedley, 1899
Sub-translucent. Described size,1.44mm by 1mm.
Norfolcioconcha iota Preston, 1913
Distinguished by the smaller size and base of shell sculptured with revolving striae. 1mm by 0.25mm , 4 whorls.
Note: The original was found in a fossiliferous deposit in the 'Limestone quarry' (Preston). Material collected from Duncombe Bay was sorted in three sizes with varying shell characteristics, the largest being 2mm by 1.25mm. Iredale suggested that there may be three species involved and even some localized subspecies. I couldn't find any at Duncombe Bay but they are almost certainly still to be found there or nearby, despite the massive clearing of the 1920s. I am fairly certain that there is only one species involved.
GENUS: Penecosta Iredale, 1844 (Charopids untoothed)
Iredale thought these unlike any charopids 'yet seen'. Discoidal with flat upper surface, smooth apex, sculpture regular, wide umbilicus, thin lips, untoothed. Disc-like. Missing(?) in Palaeo, uncommon in fossiliferous deposits (slight keeling) and rare live or difficult to finds. The problem with this is that it might be a regularly occurring variation in the development of the shell within Penecosta.
Very common in Palaeo and Prehistoric deposits, uncommon in fossiliferous deposits. Very rare live or at least difficult to find.
Penecosta mathewsi Preston, 1913
Distinct sculpture, curved riblets, 45-50 ribs on last descending whorl. 2.25mm by 0.75mm, 4 1/2 whorls slowly increasing.
Penecosta sororcula Preston, 1913
Sculpture finer and less regular than above, apex slightly higher, last whorl not descending. 1.5mm by 0.5mm, 4 1/2 whorls!!
Pennecosta harperensis Iredale, 1945 (poss. subspecies of C. mathewsi).
Smaller than C. mathewsi with finer sculpture (60 plus ribs on last whorl). Last whorl NOT descending. Note: the Harper Road valley has been largely destroyed by clearing and weed growth.
Pennecosta duncombensis Iredale, 1945
Whorls more rounded and narrow, the last descending. The apex elevated. Small aperture. Very wide umbilicus. 2.25mm by 1mm.
Pennecosta piger Iredale, 1945
Described under P. duncombensis as a possible new species. More elevated shell, coarser sculpture, larger aperture and more narrow umbilicus. 1.5mm by 0.75.
GENUS: Frustropa Iredale, 1945
Described as a more rounded charopid with a large apex, slightly elevated spire and narrow umbilicus, smooth and with an ear-shaped aperture, untoothed.
Frustropa alea Iredale, 1945
Depressedly turbinate, apex whorl smooth (1 1/2), the adult whorls sculpted with fine curved close lamellae, upper surface convex, aperture a reversed ear-shape. 2mm by 1.25mm, 4 1/2 whorls. Iredale felt that there were, 'a very large number of small mollusca yet to be discovered'.
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Zonitoid Snails
FAMILY: HELICARIONIDAE
GENUS: Allenoconcha Preston, 1913
Examples from fossiliferous deposits seem fairly homogeneous though small distinctions made in live populations are difficult to judge because of the dulling of the shell with age. Very common live. I don't understand why Iredale (and others) divided Allenoconcha and Greenwoodoconcha into so many species on shell characteristics alone, the variations are found in most populations around the Island. From my most recent stay on Norfolk Island (October-November 1997) I suspect that there may only be two species
The easiest way to describe them is that they look superficially similar to the Garlic Snail (Oxychilus alliarus), being a shining reddish brown, semi-transparent, but without the umbilicus.
Allenoconcha basispiralis Preston, 1913
Suture lightly impressed and narrowly margined below. The last whorl sharply angled.4.5mm to 4mm by 2.5mm, 5 whorls.
Allenoconcha belli Preston, 1913
This one is yellowish brown, columella margin white, base a bit convex and last whorl angled at the perifery. 3.5 to 3.25mm by 2mm, 4 whorls.
Allenoconcha mathewsi Preston, 1913
Pale yellow-brown and last whorl angled at the perifery. Narrowly callously marginated below the usual impressed suture. 4.75 to 4.25mm by 2.25mm, 5 whorls. Note: from several distinct and separated localities, so if the others are found to be normal variations of a single species, this should probably be the name to be adopted.
Allenoconcha mons-pittensis Preston, 1913
Squat; and angled perifery type, as above and below. Narrowly perforate! Yellowish brown. Narrowly marginated below impressed suture, shading in the subsutural region; last whorl sharply angled. 4.25 to 3.75mm by 1.5mm, 5 whorls.
Allenoconcha perdepressa Iredale, 1945
Slightly iridescent; narrowly marginated below impressed suture. 3.25 to 3mm by 1.25mm, 4 whorls.
Allenoconcha royana Preston, 1913
Greenish brown. Last whorl angled at perifery. 4.75 to 4mm by 2mm, 5 whorls.
Allenoconcha congener Preston, 1913
Deep reddish brown shade and less depresed form than A. royana (both lots found at Duncombe Bay), otherwise nearly the same. 4.75 to 4.25mm by 2.25mm.
Note: I have found this type in the Cook Memorial area , not far from Duncombe Bay, as a distinct population but otherwise is not too much different to the norm.
GENUS: Greenwoodoconcha Preston, 1913(Orthotype: Microcystis nux)
Differ strikingly from Allenoconcha but obviously allied. A more solid and elevated shell and has distinct colouration. Not umbilicated but the region is well depressed. Only two of the following will be found to represent distinct species, G nux and G casteneocincta.
Greenwoodoconcha nux Sykes, 1900
Similar to G. castaneocincta but without the white band and deep red brown colouration. The shell is more squat, dull yellowish and has a distinctive white mark behind the lip. 7mm by 4mm, 5 to 5 1/2 whorls.
Missing in fossiliferous deposits. A high altitude species and common in the National Park. Indigenous.
Greenwoodoconcha castaneocincta Sykes, 1900
One of the most easily recognized species on Norfolk Island because of its strong colour pattern. Common live and in the Palaeo and fossiliferous deposits. 7.8mm by 3.9mm, 5 1/2 whorls.
Greenwoodoconcha castaneocincta sericea Iredale, 1945
Iredale names this as a subspecies because of the smaller size and slightly higher spire. It was located at Ball Bay. It might have been a low altitude variety or simply under pressure from clearing and predation: I didn't find any specimens at Ball Bay so this variety? may be extinct. B.J. Smith has placed this in Incertae sedis.
Greenwoodoconcha tomi Preston, 1913
A plain reddish brown shell, quite angled at the perifery. Impressed suture with distinct margin below. Large aperture 2.5mm by 2mm. Sculpture wavy and curved. 5.25 to 4.75mm by 3mm.
GENUS: Iredaleoconcha Preston, 1913
I was lucky enough to find one single specimen on the eastern slopes of Mount Pitt and one curious variation in the Palaeo deposit. Iredale seems to state that no drawings were made and the original specimens appear to have been lost.
From a distance the shell resembles Greenwoodoconcha but is yellowish, shining of a suborbicular shape. The astonishing feature of this shell is the widely grooved suture appearing on the last whorl as a 'supraperipheral channel'; on profile looking like a series of narrow terraces. Preston thought it very nearly resembled Diepenheimia of the Obi Islands, West Indies, except that the Norfolk one has no perforation.
Iredaleoconcha inopina Preston, 1913
Found both live and in the Linestone quarry originally. 2 to 1.75mm by 0.75mm, 3 1/2 whorls. I would suggest that this might just be an immature specimen, though the proportions are slightly different and the colour is described as yellowish and the following one brown.
Iredaleoconcha caloraphe Preston, 1913
Originally found at Duncombe Bay. 4.25 to 3.75mm by 2mm, 5 whorls. The one I found on Mt Pitt was intermediate in size between the two species (3.5mm by 1.8mm), though in proportion closer to I. caloraphe.
Iredaleoconcha sp (palaeo deposit).
This specimen which I found in the Palaeo deposit had tighter coiling, sporting 7 whorls!!
GENUS: Nancibella Iredale, 1945
One specimen found in the Palaeo deposit. The Palaeo specimen is larger than those previously recorded--reddish hue at the top--perhaps a sub-species? Seems closely related to Iredaleoconcha but has a much flatter spire, more whorls, and without the characteristic suture 'steps' (though note the extra whorls in the Iredaleoconcha palaeo find). Formerly placed after Pittoconcha.
Nancibella Quintalae Cox, 1870
At last found two small but healthy populations in November 1997 in the National Park. Given measurements are 4mm (max) to 3.5mm by 3mm to 2mm, 8 whorls!!
Nancibella sp Palaeo
The specimen I found in the Palaeo deposit had a reddish top, or spire. Measured 4.5mm by 2.5mm (or a fraction less), which is flatter than those found in the wild. 7-8 whorls.
GENUS: Buffetia Iredale, 1945
Described as depressedly conic, yellowish brown, thin transparent shell. To me the sculpture of closely set arcuate ribbing (plicae) is a very distintive feature, as well as the elegant shape. Placed after Allenoconcha congener by Iredale. Alied to Pittoconcha.
Buffetia retinaculum, Preston (Nitor retinaculum, Preston: Allenoconcha ? retinaculum, Iredale). 3mm to 2.5mm by 1.5mm, 4 whorls.
NOTE: This shell has more in common with Pittoconcha than Allenoconcha. Iredale admitted that it was not a true Allenoconcha, so proposed a subgeneric value with the name Buffetia (but should really have a double 't'?). Also an uncarinated fossiliferous type. Rare in all fossiliferous deposits and live but fairly common in the Mt Cross vicinity. Is often found with Pittoconcha. The shell is so completely different from Allenoconcha, I can't understand why it was placed with it.
GENUS: Pittoconcha Preston, 1913
Three or four specimens found in the Palaeo deposit (significant in terms of the present day population is found in the higher altitudes of Mount Bates). Missing in other fossiliferous (low altitude) deposits? Seems to be a higher altitude species (though one found at the base of Pop Rock). Uncommon live.
Pittoconcha concinna Preston, 1913
Elegant distinctive shell, turbinate with inflated spire, very strongly and robustly ribbed but not as regular (or the spire so low) as illustrated. Given measurements 3mm by 1.75mm, 4 whorls.
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GENUS:
Only one worn specimen found in the palaeo deposit. Resembling Pittoconcha and Buffetia but the whorls rounded even more inflated. The shell may represent a lowland species during times of much lower sea levels and became extinct since the last great rise in sea level.
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FAMILY: HELICARIONIDAE
Formerly Fanulidae.
GENUS: Fanulena Iredale, 1945
Common in Palaeo deposits where the specimens are large. Very common in fossiliferous deposits. There are several variations. Common live, living in and around rotting logs or timbers (unlike most other species). Fanulena does not have sculpted apical whorls
Fanulena insculpta Pfeiffer, 1846
These seem to be the large broad type with very strong ribbing. The spire height varies. Not well described in the literature and I suspect that it is the same as F. testudo.
Fanulena testudo Preston, 1913
I suspect it to be the same as F. insculpta. A common shell on present day Norfolk and all fossiliferous deposits. Columella has a tooth-like projection. Given measurements, 7.75 to 7mm by 4.5mm, 5 whorls.
Fanulena perrugosa Iredale, 1945
Formerly Parcolena perrugosa and before that Fanulena perrugosa! I don't understand this one. The apical whorls are smooth so Iredale placed it initially under Fanulena instead of Lutilodix. Described as not having the periferal pinching of F. testudo. The columella does not have a tooth like projection. Rounded base and whorls but the perifery is subkeeled, the latter feature unlike the unnamed Palaeo species. This is very likely a usual variation of F. insculpta.
GENUS:
My anchor name for a species that became extinct before the fossiliferous deposits of Cemetery Bay (over 1000 years). Common in the Palaeo deposit. One solitary example (out of thousands of shells) at Cemetery Bay but I suspect it to be a windblown intrusion from a deposit in the direction of Point Hunter. A very early extinction.
GENUS: Lutilodix Iredale, 1945
These are superficially similar to Fanulena but is vertically orientated, almost conical. The base is flattish, slightly impressed, apart from the aperture which comes out at an angle. The columella is smooth. The apex sculpture is similar to the rest of the shell. Often covered in mud, which may explain the functions of the small hairs sometimes seen.
Lutilodix imitatrix Sykes, 1900
Common in the Palaeo and fossiliferous deposits. Uncommon live. 5.5mm by 5mm, 5 1/2 whorls.
GENUS: Dolapex Iredale, 1945
This group (Fanulena/Lutilodix) have overlaps and I think Iredale would have been tempted to make even finer distinctions and propose several more species. May just be a slight variation of F. insculpta.
Dolapex amiculus Iredale, 1945
Two apex whorls are finely sculptured. Columella toothed! (white). . Can be faintly flamed with white radials.The base is slightly convex and pinched below the sharp keeled perifery. Two specimens seemed to fulfil the written criteria near Cook Memorial. 5mm by 4mm.
Dolapex fraturnus Iredale, 1945
Proposed by Iredale for a larger version of D. amiculus. 6mm by 5mm. Very likely not justified as a separate species.
GENUS: Roybellia Preston, 1913
Very depressed and thin shelled snail, adapted to slide between leaves on the ground. Two species are listed but I believe them to be the same. Live bearing. A high altitude species, no trace of them found in fossiliferous deposits. (Orthotype, Trochonanina platysoma).
Roybellia platysoma Sykes, 1900
Umbilical depression. Given measurements, 7.5mm by 2.5mm, 5 whorls.
Roybellia depressa Preston, 1913
Almost no umbilical depression. I would suspect that this is the description of an immature specimen. Given measurements 6.5 to 5.5mm by 1.5mm.
FAMILY: HELICARIONIDAE (continued)
Formerly Advenidae.
GENUS: Advena Gude, 1913
Several varieties have been listed as species but I found some of those variations in the National Park in one location (including the so called Philip Island species), hence suspect them to be all of the one species. There is also some confusion in the species descriptions (note Philip Island and descriptions). The Nepean Island fossiliferous one with the flatter spire was found in the fossiliferous deposits also. Very common in the Palaeo deposit, fairly uncommon (numerically) in the fossiliferous deposits. Almost extinct live.
Advena campbelli Gray, 1834
Bi-colour type. The largest indigenous species on Norfolk Island, almost extinct. Live bearing, the baby shells are often found in the shells of fossiliferous examples. This is used to describe the bi-colour shell, the spire is a light tan, or fawn colour, the base a deep purple/brown to black colour (appears reddish in fossiliferous or long dead examples). Fossiliferous examples are often larger.
Advena campbelli var charon Preston, 1913
Uniform dark coloured type. This was used to describe the mainland shell of one uniform colour, a deep purple/brown colour. I found both this and the bi-colour shell (originally collected on Phillip Island) on Mt Pitt. Also found with a white zone along the suture. 11mm by 7mm.
The type with the white zone above the suture may only be due to the 'slipping' of the coil - only found on the uniform colour type.
Advena nepeanensis Preston, 1913
Not justified. Used to describe the Nepean Island fossiliferous examples but such variations as 'broader and with less elevated spire' I noted in the Kingston fossiliferous examples also. 27mm to 23.5mm by 15mm. B.J. Smith placed this one in incertae sedis.
GENUS: Mathewsoconcha Preston, 1913
Since my latest visit to Norfolk Island (1997), I conclude that there are probably four justifiable species:
- white banded tan or faun shell with a lowish turban. Highly positioned periferal keeling seen in juveniles. Only surviving form on Norfolk. M. belli Preston, 1913.
-white banded tan or faun shell with a high turban, distinctly larger and more inflated than the above. Rediscovered on Philip Island 1980s/1990s (so far about five or six 'fresh' shells collected). It is not known if the juveniles are flat-topped and keeled as the above. Very likely M. phillipii Grey, 1834 if that one had a white band.
- white banded shell of a large and squarish appearance. Very flat spire in juveniles and adults. M.microstriata. Extinct.
-red/brown banded species. M. vexillum. Extinct.
-There are some fossiliferous types which may prove to be additional species, for example a very rounded compact type found semi-petrified in fossiliferous deposits.
Mathewsoconcha belli Preston, 1913 (Syn. M. norfolkensis)
Rare in the Palaeo deposit, very common in the fossiliferous deposits. Distinguished by the white band. Almost extinct. 10 to 9mm by 6.5mm, 4 1/2 whorls (M. norfolkensis) and 9.25mm to 8.25mm by 6mm, 4 whorls (M. belli).
Mathewsoconcha albocinta Preston, 1913
Used to describe a Kingston fossiliferous type similar to M. belli, note the white band. 8.75 to 7.5mm by 5.5mm, 4 whorls.
Mathewsoconcha vexillum Preston, 1913
Missing in the Palaeo deposit, common in the fossiliferous deposits. Has a suprasutural reddish orange band and periferal band on the last whorl instead of a white band. 9 to 8mm by 6.5mm, 5 whorls. Extinct.
Mathewsoconcha microstriata Preston, 1913
A large size version of M. belli. Though stated to be colourless (was found in a fossiliferous deposit after all) but some noted with a white band. In the Palaeo and fossiliferous deposits. 16 to 14mm by 10mm, 4 1/2 whorls. Extinct unless it is a commonly occurring 'freak' in the M. belli population. I found one at Hundred Acre among a strong M. belli population, it measured 15mm by 9mm..
Mathewsoconcha phillipii Preston, 1913
Used to describe the Philip Island variety but as it had a white zone was probably the same as M. belli. Few details given. 14mm by 8mm (8lines by 5lines).
Mathewsoconcha suteri Sykes, 1900
Very common in the Palaeo deposit. Uncertain otherwise. Extinct? Used to describe a shell without a brown or white band but in some cases, particularly from fossiliferous deposits, the white band is difficult to see (M. belli). The original specimen needs re-examination. 12mm by 8.8mm, 5 whorls.
Mathewsoconcha Grayi Sykes, 1900
It seems that some examples may have been found in the wild rather than exclusively from fossiliferous deposits. The red banded Mathewsoconcha is definitely a separate species, it is not a variation amone the white banded types. 18mm by 13.5mm, 5 1/2 whorls.
NOTE: The following were grouped under the genus Belloconcha (Preston, 1913) but are only fossiliferous versions of Mathewsoconcha. B.J. Smith has sensibly placed them under Mathewsoconcha but probably neither of the following are justified and should be grouped under the above. The band fades as the shell gets older or becomes calcified.
Mathewsoconcha elevata Preston, 1913
A Nepean Island fossiliferous variety said not to have a trace of colour. The chief differential is said to be the non-bulging columella. 14.74 to 12.75mm by 11mm, five whorls.
Mathewsoconcha compacta Preston, 1913
Described as pale yellow with a white periferal band but that is what one would expect from M. belli, if found in a fossiliferous condition. 10 to 9mm by 6.5mm, 4 1/2 whorls.
GENUS: Quintalia Preston, 1913
Rare in the Palaeo deposit and on Nepean Island. Orthotype: Caracolla stoddartii. Found also in fossiliferous deposits at Kingston. Extinct. This is an interesting shell because it appears like a cross between a Advena and Mathewsoconcha but has the colour flashes only seen in Fanulena! It was collected from Philip Island but I doubt if a live one was ever collected on Norfolk. With the loss of vegetation on Philip Island, it became totally extinct (though no rats on Philip Island). In November 1997 I found a shell which seemed to answer the description of Q. stoddarti but as juveniles of M. belli often have a carination (though set high unlike Quintalia which is set in the middle of the shell as seen in profile) caution is advised until a better sample can be obtained.
Quintalia stoddarti Gray, 1834
14mm by 8mm, 'some specimens were larger' (Iredale). I found a number in the main fossiliferous deposits at Kingston but none were larger than 11mm wide. Quintalia stoddarti intermedia, taxonomic decision for synonymy, B.J. Smith (1992) but I feel that there are still two species to be described under Quintalia. The name was devised to describe the Nepean Island fossiliferous finds. All the ones I've seen have the 'transverse colour blotches', more like flames, but only one specimen with the 'subperiferal chestnut band'-- Kingston fossiliferous deposit which in many cases do not seem to differ. Given measurements 13 to 11.25mm by 8mm.
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FAMILY:
GENUS:
Helix patescens listed incorrectly, at present, as 'Quintalia flosculus'
This species needs a family and a genus. It was misnamed by Iredale who thought it must be Quintalia but it has obviously nothing in common with Quintalia. It does not belong to the family Helicarionidae. It is a unique species on the Island, one of the few living on plants and shrubs in the higher altitudes, usually on the underside of leaves of Macropiper excelsum, Meryta augustifolia, Meryta latifolia and Pennantia endlicheri. The snail has a very fine see-through shell, the lower half having a distinct yellow colour the upper half is milky white. It has the largest operculum in relation to shell size of any species on the Island. Cox named it Helix patescens (1870 - illustrated). Patescens should be the only part of the name that has justification for retention. Not found in fossiliferous deposits. High altitude species.
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FAMILY: ZONITIDAE
GENUS: Hawaiia
A classic case of over-enthusiasm for naming species!
Formerly described under genus Johannesoconcha Preston, 1913 (noted as minute, vitreous, turbinate and umbilicate) and genus Macgillivrayella Preston, 1913 (Described as depressedly turbinate, vitreous, somewhat broadly perforate).
Hawaiia miniscula Binney, 1840
Synonymy: Johannesoconcha multivola Preston, 1913 (as for the genus and is white1.25mm by 0.5mm, five whorls rapidly increasing--the last whorl 'scarcely ascending', aperture obliquely sublunate. Umbilicus wide and well-like) and Macgillivrayella crystallina Preston, 1913 (noted as orbicular, white , semitransparent, suture deeply impressed, umbilicus wide and moderately deep. 2.5 to 2.25mm by 1mm, 3 1/2 whorls).
Placed in incertae sedis by B.J. Smith (1992) but very likely also being Hawaiia miniscula: Johannesoconcha pusillior Preston, 1913 - (more depressed and less well-like umbilicus. 1.25mm by 0.25mm, ? whorls) and Johannesoconcha minuscula Preston, 1913 - (fossiliferous, white, unbilicus moderately narrow but well-like. 1mm by 0.25mm, 3 1/2 whorls). There may have been contamination at the Quarry because Hawaiia miniscula is to be found living in or near such areas where fossiliferous material; is found.
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"FAMILY ?" (Iredale). Placed in incertae sedis under CHAROPIDAE (B.J. Smith (1992)).
GENUS ?
Helix depsta Cox, 1870 ("Charopa (?) depsta Cox, 1870").
Simply described as having a weakly grained structure and recalls the structure of Trachiopsis. Not re-found by Roy Bell or H.C. Quintal. I think I found one example off Selwyn Pine but measured 3-4mm max (the records allow 6mm max).
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FAMILY: Placed incorrectly in Helicarionidae (B.J. Smith (1992)).
GENUS: Dendrolamellaria Preston, 1913
Dendrolamellaria mathewsi Preston, 1913
Found at Ball Bay. The description is that of the marine genus lamellaria which Preston wrote 'resembles almost exactly in form. Iredale wrote 'a study of the animal might provide some interesting surprises'. 18.75 to 15.5mm by 14mm, 3 whorls.
The surprise is that it is a marine species. It ended up in the tree because that is where it was dropped by sea birds. Sea life is often found in the trees at Ball Bay and elsewhere on the Island-- carried there by birds feeding their chicks. I have found identical shells along the beach at various times.
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GENUS: Posticobia
"Paludestrina norfolkensis" Sykes, 1900
Considered at present to be a Posticobia. Once found in freshwater streams on Norfolk, 'A very small dark-brown species, with tumid whorls; the peristome is generally thickened all round'.
I have tried to find specimens as have others before me (Winston Ponder?) but no luck. I expect that they may have been 'flushed out' during 'The Flood' around 1936 which devastated the Island. Some must have survived somewhere. Another unsuccessful search was made by me in November 1997. Stephanie Clark has based her MSc (1997) on the research of this and related species. Stephanie suspects that the snail was indigenous.
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Several similar micro species found which I could not identify.
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FAMILY:
GENUS:
Unrecorded species, probably the most beautiful of Norfolk's snail species. Should have relatives in other Pacific Island and New Guinea etc., judging by illustrations I have seen. Fairly common in the Palaeo deposit, common in the fossiliferous deposits and very rare live (I found one population on an east slope of Mount Cross).
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INTRODUCED SPECIES
FAMILY: PUPILIDAE
GENUS: Gastrocopta
Gastrocopta strangeana, Iredale, 1937
Introduced. Formerly Australbinula strangeana. Not found in fossiliferous deposits (although two specimens appear close to this type). Otherwise found only at Emily Bay, Kingston and possibly Cascade (1997).
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FAMILY: VALLONIIDAE
GENUS: Valonia
Valonia pulchella Müller, 1774
Introduced. Grass Snails. Very common in the long grasses at Kingston and some south-east coastal areas. Has contaminated the sand quarry deposits, where disturbed.
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FAMILY: BRADYBAENIDAE
GENUS: Bradybaena
Bradybaena similaris Ferussac, 1821.
Common in overgrown gardens and spreading. Both the banded and plain versions (as in NSW Australia). Can be mistaken for Mathewsoconcha at a distance.
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FAMILY:
GENUS: Helix
Helix (Cornu) aspersa Müller, 1774
Common Garden Snail. Not found in early archaeological contexts. Shells have been transported into holes in convict-built structures at Kingston, probably by rats. Common in gardens. Specimens found in the National Park are very dark and difficult to see in the leaf litter. Specimens in the 'new' pine forest at Emily Bay are larger than found elsewhere, one or two shells were so large that they could be mistaken for French culinary snail shells.
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FAMILY: ZONITIDAE
GENUS: Oxychilus
Oxychilus alliarus Miller, 1822
Garlic Snail. This glossy snail is to be found in some of the weed areas and gardens around the Island. They can appear superficially like Allenoconcha sp but are distinctly umbilicated.
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NOTE: There were a number of minuscule species, introduced and indigenous which need further work. Add common introduced water snails!
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Dr Robert V J P Varman.
Updated: 27 April 1998 - Uploaded:3 July 1998
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FRIENDLY NOTE: I am not a trained taxonomist, anchor names are used where a name is in doubt. All shells described have been drawn to scale and the specimens bagged and numbered with details as to where the snails were found and when. Journals document the various excursions I have made. The decision to share what I have discovered to this stage is based on the thought that others studying related species or geographical areas may benefit in some way and may also share their expertise.