Microcochlis parva, Yoo, 1994

Yoo, E. K., 1994, Early Carboniferous Gastropoda from the Tamworth Belt, New South Wales, Australia, Records of the Australian Museum 46 (1), pp. 63-120 : 88-89

Microcochlis parva n.sp.

PI. 12 figs 1-5

Description. Shell minute, relatively high-spired turbiniform, narrowly phaneromphalous. Protoconch simple consisting of one and one eighth smooth whorls with sharp irregular boundary between protoconch and teleoconch. Teleoconch whorl profile arched in early stage and rather straight in late stage, suture shallow, ~ase subangular; first 11;4 whorls with gently prosocline, fme collabral lirae followed by strong collabral cords extended to umbilicus, with cords straight, prosocline, and evenly spaced but becoming gradually wider with growth, omamented by 4 spiral rows of pustules on final whorl between periphery and the upper suture. Aperture subrectangular, inner lip thin, nearly straight, outer lip thin, straight prosocline.

Dimensions. Figured specimens	H ( F78446 ) 2.2 mm	W 1.5 mm
	( F78447 )1.4	0.8

Dimensions. H Holotype ( F78437 ) 2.1	W mm 1.5 mm	PA 56°	NW 4~
Paratypes ( F78438 a)1.4 ( F78438 b)1.3	1.2 1.0	54 56	3~ 4

Types. Holotype ( F78437 ), 2 figured paratypes ( F78438 ) and 2 unfigured paratypes ( F78439 ).

Type locality. Behind 'Kyndalyn' homestead, 10 km south-west of Somerston, NSW (Locality 24).

Stratigraphic position. In base of oolitic limestone in the Kyndalyn Mudstone Member of the Merlewood Formation.

Dimensions. H	W	PA	NW
Holotype ( F78451 ) 1.6 mm Paratypes ( F78453 )1.6 ( F78452 )1.6	1.5 mm 1.6 1.4	85° 95 90	4~ 4~ 4

Geographic distribution. Type locality only.

Geological age. Middle or late Visean.

.Etymology. Derived from the Latin parvus meaning mmute.

Remarks. Microcochlis parva n.sp. differs from Eucochlis umbiliparva n.sp. in having a smaller shell, short blunt protoconch and prominent spiral rows of pustu!es. Figures 1 and 2 ~n Plate 12 are juveniles, showmg an arched whorl profile and only faint expression of spiral cords. The spiral angulation begins to appear at 2~ whorls.

Figures

Plate 12. Figs 1-5. Microcochlis parva n.gen., n.sp. l. Paratype, apertura1 view lA mm x l.2 mm (F78438a). 2. Paratype, apertural view l.3 mm x l.0 mm (F78438b). 3. Holotype, apertural view 2.1 mm x l.5 mm (F78437). 4. Oblique apical view, protoconch and early stage of teleoconch of Fig. l. 5. Apical view. Locality 24. Figs 6-1l. Kyndalynia inflata n.gen., n.sp. 6. Paratype, apertural view, slightly tilted forward 1.1 mm x l.0 mm (F78441a). 7. Holotype, side view, height l.3 mm (F78440). 8. Paratype, apertural view 1.0 mm x l.0 mm (F78442). 9. Paratype, apertural view 1.2 mm x l.0 mm (F78443). 10. Paratype, apertural view, slightly tilted forward 1.1 mm x 1.0 mm (F78441b). 1l. Protoconch of holotype. Locality 24. Bar scale 0.1 mm.

Fig. 1. Distribution of Carboniferous outcrop and examined localities,

Fig. 2. Stratigraphic nomenclature.