Gabbia carinata, Ponder, 2003

Ponder, Winston F., 2003, Monograph of the Australian Bithyniidae (Caenogastropoda: Rissooidea), Zootaxa 230 (1), pp. 1-126: 106-109

publication ID

http://doi.org/ 10.11646/zootaxa.230.1.1

publication LSID

lsid:zoobank.org:pub:AE9A8BE3-1CBD-4958-991A-C6EC1F203AF2

DOI

http://doi.org/10.5281/zenodo.5098513

persistent identifier

http://treatment.plazi.org/id/0C12051D-2304-FF97-FECC-FEE2CE0BB5C2

treatment provided by

Felipe

scientific name

Gabbia carinata
status

n.sp.

Gabbia carinata   n.sp.

Etymology Carinatus (L.) – keeled.

Type material

Two mudholes, by Walker Ck, Qld, 17° 28.030'S, 141° 10.790'E, in fine mud around edges, 31 MAY 1997, W.F.Ponder, V.Kessner & D.L.Beechey (Holotype, AMS C.417683; paratypes AMS C.331877, 1018 wet, 30+ juveniles, 10 dry, 4 on SEM stubs; NTM P21379 View Materials , 15; QM MO71721, 10) GoogleMaps   .

Additional material examined

Northern Territory: Tawarrila Ck, S. of Bing Bong, W   . Gulf of Carpentaria , 15° 46.580'S, 136° 25.170'E, amongst macrophytes, 23 AUG 1994, W.F.Ponder, G.Wilson & V.Kessner ( AMS C.327927, several) GoogleMaps   .

Queensland: billabong S of Tully Inlet, 2.5 km W of Settlement Ck, Wollogorang Stn   , Gulf of Carpentaria , 16° 45.700'S, 138° 8.950'E, 25 AUG 1994, V.Kessner ( VKC 23956 View Materials , 20 +; AMS C.318640, 6); billabong E of Settlement Ck GoogleMaps   crossing, Wollogorang Stn   , Gulf of Carpentaria , 16° 53.450'S, 138° 9.280'E, 25 AUG 1994, V.Kessner ( VKC 23955 View Materials , 20 +; AMS C.318576, 6); billabong above Tully Inlet, W. of Mornington Is GoogleMaps   ., Gulf of Carpentaria, 16° 45.710'S, 138° 8.960'E, amongst weed & macrophytes, 25 AUG 1994, W.F.Ponder, G.Wilson & V.Kessner ( AMS C.327879, several; AMS C.327893, 20+); billabong off road to beach nr Tully Inlet, W. of Mornington Is GoogleMaps   , Gulf of Carpentaria , 16° 46.900'S, 138° 10.140'E, 25 AUG 1994, W.F.Ponder, G.Wilson & V. Kessner ( AMS C.327883, 20+); permanent billabong E of Settlement Ck., Wollogorang Stn GoogleMaps   , Gulf of Carpentaria , 16° 46.920'S, 138° 10.170'E, 25 AUG 1994, V.Kessner ( VKC 23957 View Materials , 20 +; AMS C.318618, 6); 65 km by road NE of Woologorang GoogleMaps   HS, nr Qld border   , Gulf of Carpentaria , 16° 47.000'S, 138° 10.170'E, in shallow billabong, in mud, 29 AUG 1988, V.Kessner ( AMS C.300776, 3; VKC 13881 View Materials , 14; GoogleMaps   AMS C.318591, 3); 7 km SSE Scrutton Ck crossing, Gulf of Carpentaria GoogleMaps   , 17° 35.750'S, 138° 26.420'E, small billabong in Cliffdale Ck drainage, 30 AUG 1988, V.Kessner ( AMS C.300777, 1; VKC 13882 View Materials , 1); GoogleMaps   Jam Tin Yard, Devils Gate Stn, 17° 24.600'S, 138° 34.950'E, on mud, 24 MAY 1997, W.F.Ponder, V.Kessner & D.L. Beechey ( AMS C.326805, sev); GoogleMaps   M Lagoon next to M Ck on Normanton ­ Burketown Rd, 18° 6.070'S, 140° 16.880'E, on mud amongst vegetation, 29 MAY 1997, W.F.Ponder, V.Kessner & D.L. Beechey ( AMS C.331861, 20+); GoogleMaps   Twelve Mile Ck waterholes at Karumba to Normaton Rd, 17° 31.730'S, 141° 9.570'E, 31 MAY 1997, W.F.Ponder, V.Kessner & D.L. Beechey ( AMS C.332842, 20+); GoogleMaps   Brannigan Ck at Karumba to Normanton Rd (side channel with waterholes), 17° 28.660'S, 141° 10.600'E, 31 MAY 1997, W.F.Ponder, V.Kessner & D.L. Beechey ( AMS C.331863, 20+); GoogleMaps   waterhole in river flood channel of Gilbert R, ca. 0.2 km S of Gilbert R, 17° 10.450'S, 141° 45.990'E, on weed & mud, 1 JUN 1997, W.F.Ponder, V.Kessner & D.L. Beechey ( AMS C.333670, 1; GoogleMaps   AMS C.381244, 5); waterhole on Dogwood Ck on Burke Developmental Rd , 16° 51.730'S, 141° 58.060'E, on weed & mud, 1 JUN 1997, W.F.Ponder, V.Kessner & D.L. Beechey ( AMS C.326793, 20+); GoogleMaps   Clarks Lagoon, Dunbar Stn on Burke Dev Rd , 16° 1.030'S, 142° 25.010'E, on weed, 3 JUN 1997, W.F.Ponder, V.Kessner & D.L. Beechey ( AMS C.381474, 14); GoogleMaps   Nolan Ck at Burke Developmental Rd , 16° 48.670'S, 144° 10.090'E, 4 JUN 1997, W.F.Ponder, V.Kessner & D.L. Beechey ( AMS C.346293, 20+) GoogleMaps   .

Description

Shell ( Figs 26H,J View FIGURE 26 , 36E,F View FIGURE 36 ) small (up to 5.6 mm in length), trochiform with strong spiral ridges, up to 4.4 convex whorls shouldered in upper third by upper­most spiral ridge. Protoconch of about 1.3­1.5 smooth whorls. Teleoconch sculptured with heavy, flat­topped spiral ridges, 3 on penultimate whorl, 6­11 on last whorl; intermediate cords present between main ridges, especially on last whorl, with one between main ridges on upper part of whorl and, usually, 3 between upper and lower basal ridges; weak spiral lines and threads also present; spiral sculpture crossed by much finer collabral growth lines; base convex, subangled by lower basal ridge; umbilicus wide, rimmed by lower basal spiral ridge and with 1 or 2 ridges within. Aperture broadly ovate; peristome moderately thickened in adults; outer lip prosocline. Colour: shell opaque to sub­translucent; periostracum thin to moderate, yellow­white to brown. One or two varices typically present, represented by rather irregular lines or breaks.

Dimensions. See Table 28 for dimensions of holotype and Appendix, Table 29 View TABLE 29 , for summary shell dimensions and whorl counts.

Operculum ( Fig. 32O,P View FIGURE 32 ) typical of genus. Ovate, yellowish­white (unless stained), slightly to moderately concave, concentric growth ridges distinct; inner surface sculptured with low, concentric ridges.

Radula (Appendix Table 30 View TABLE 30 ; Fig. 37F,G View FIGURES 37 ) typical of genus. Central teeth with 3­5 cusps on either side of median cusp; median cusp about 1.3­1.4 longer than adjacent cusps, base about twice as wide, initially parallel­sided to slightly tapering, distally tapering to blunt to sharp point. Face of central tooth with 2­3 pairs of cusps parallel to lateral margin, inner pair much larger than others, about half total height of tooth. Lateral margins straight to slightly concave; at about 50­60º, basal tongue short, rounded. Lateral teeth with cusp formula 3­4 + 1 + 4­6; cutting edge about third length of lateral part of tooth; median cusp up to about twice as long as adjacent cusps, broad, parallel­sided to slightly tapering, with rounded end; upper edge of lateral part of tooth at about 50­60º to cutting edge, lateral edge straight. Inner marginal teeth 21­25 cusps, outer marginal teeth long and very slender with expanded bases, with 5­9 cusps.

Head­foot with unpigmented foot, snout pale grey, tentacles with central pale grey stripe. Mantle roof unpigmented over rectum/kidney – remainder with black with large white blotches.

Anatomy. Gill with apices at about quarter of width from right; 52­58 filaments (n=2). Osphradium opposite middle of gill. Penis and accessory lobe shorter than penial lobe, distal end of accessory lobe lacking swelling or distinct sucker; accessory gland moderate to short. Pallial oviduct ( Fig. 34D View FIGURE 34 ) similar to G. vertiginosa   but with relatively shorter albumen gland; bursa copulatrix narrow, extends to posterior pallial wall (AMS C.326793, AMS C.327883).

Distribution ( Fig. 39 View FIGURE 39 ) and habitat. Coastal plains of the Gulf of Capentaria and the eastern base of Cape York. In billabongs and pools on mud, although often associated with macrophytes and algae.

Remarks

This species is very distinctive amongst the Australian fauna with its trochiform shell with an open umbilicus and strong spiral ridges. However, Mysorella costigera   has a very similar shell to G. carinata   but differs in being much larger (about twice as large), in having a very heavy operculum, in the axial sculpture being heavier and sharper, especially on the base, and in the edge of the outer lip being very slightly reflected in adults (simple in G. carinata   ). M. costigera   and has been described anatomically (from India) by Seshaiya (1930). The central teeth of the radula reportedly have central teeth with only a single pair of basal cusps ( Annandale, 1920), although Seshaiya (1930) noted 1­3 pairs and Starmühlner (1974) 3 pairs, although the 2 nd and 3 rd pairs are small.

Mysorella costigera   is the type species of Mysorella Godwin­Austen, 1919   . Its anatomy, as described by Seshaiya (1930), closely resembles that of Gabbia   . No mention of a seminal receptacle is made in the description of the female reproductive system and it was probably overlooked as this structure is present on the outer side of the middle of the albumen gland (opposite the entry point of the coiled renal oviduct) in G. carinata   . Similarly, the bursa copulatrix is not recognised as such but is clearly present as the non­glandular arm of the V­shaped lumen ( Seshaiya, 1930, textfig. 27). However, this was open to the oviduct lumen along most of its length rather than having a small anterior opening. This configuration is similar to that seen in sub­mature specimens of G. carinata   but differs from the bursa seen in mature specimens, which is closed off from the ventral channel for most of its length. Thus it is likely that the female specimens examined by Seshaiya (1930) were not fully mature, which is also probably the reason that a seminal receptacle was not reported. Given the gradation of spiral sculpture with other shell sculptural patterns, and the lack of any obvious anatomical differences reported for Mysorella   [on the assumption that the female system described by Seshaiya (1930) was submature], the recognition of a distinct subfamily Mysorellinae ( Annandale, 1920)   for Mysorella   , or even a distinct genus, is questionable on the available evidence. Thus, pending a detailed assessment of the relationships of the group, Mysorella   is tentatively regarded here as a synonym of Gabbia   .

Pseudovivipara Annandale, 1918   and Parafossarulus Annandale, 1924   are the only other Asian bithyniid genus­group name based on species that have spiral ridges on the shell. However, both these taxa, which are probably synonyms (Ponder, pers. observ.), have a larger, tall­spired, non­umbilicate shell. They also differ from most other bithyniid genera in having the basal cusps of the central teeth aligned horizontally, and in a number of anatomical differences.

R

Departamento de Geologia, Universidad de Chile

Kingdom

Animalia

Phylum

Mollusca

Class

Gastropoda

Order

Littorinimorpha

Family

Bithyniidae

Genus

Gabbia

Loc

Gabbia carinata

Ponder, Winston F. 2003
2003
Loc

G. carinata

Ponder 2003
2003
Loc

G. carinata

Ponder 2003
2003
Loc

Parafossarulus

Annandale 1924
1924
Loc

Mysorella Godwin­Austen, 1919

Godwin-Austen 1919
1919
Loc

Mysorella

Godwin-Austen 1919
1919
Loc

Mysorella

Godwin-Austen 1919
1919
Loc

Mysorella

Godwin-Austen 1919
1919
Loc

Pseudovivipara

Annandale 1918
1918
Loc

Gabbia

, Tyron 1865
1865
Loc

Gabbia

, Tyron 1865
1865