Stapafurdius glaber, Simone, 2021

Simone, Luiz Ricardo L., 2021, Stapafurdius, a new genus of Bulimulidae (Mollusca, Eupulmonata) from Bahia, Brazil, with two new species, Papéis Avulsos de Zoologia (Pap. Avulsos Zool., S. Paulo) 61, pp. 1-7 : 2

Stapafurdius glaber sp. nov.

( Figs. 1-12 , 24-26 ) http://zoobank.org/ B21ABE18-E5FE-4B08-AC63-FA4B51085F64

Types: Holotype MZSP 154048 ( Figs. 1-6 ) . Paratypes MZSP 153803, 5 shells, MZSP 154047, 9 shells ( Figs. 7-8, 11-12 ), from type locality.

Type locality: BRAZIL. Bahia: Ibicoara ; ItuaÇu, TanhaÇu, 13°55 ′ 23″S, 41°16′35″W [Wesley Vailant col., iii/2021] ( Fig. 30 ).

Etymology: The specific epithet is from Latin glaber , meaning smooth, an allusion to the lack of the shell sculpture.

Diagnosis: Shell rather conic, sculpture missing except for growth lines.

Description

Shell: About 10 mm, elongated, slightly turriform; width ~ 36% of length. Spire angle ~ 30°, growth increasing relatively uniformly, except for peristome slightly dislocated externally. Color pale beige, with small, punctiform brown spot, of apparent random distribution, coalescent in some regions forming irregular axial bands ( Figs. 1, 3, 7, 11 ). Protoconch ( Figs. 5, 12 , 25, 26 ) of 2.2 whorls, width 1.2 mm; whorls relatively rounded, suture deep; sculpture delicate net of spiral and axial lines, equally predominating, uniform, easily eroded ( Fig. 5 ); ~ 45% of shell width, ~ 8% of shell length; transition with teleoconch relatively clear, prosocline, ~ 20° in relation of longitudinal axis ( Figs. 25, 26 ). Teleoconch of ~ 4 whorls, suture relatively shallow, but well-marked; transverse section rounded ( Fig. 6 ); growth relatively uniform, except for peristome, slightly dislocated externally to right. Sculpture missing, except for growth lines and scanty axial undulations ( Fig.26 ); surface relatively glossy,small regions of dark spots with weak depression ( Figs. 3, 8, 10 ). Aperture antero-posteriorly elongated, width ~ 40% of length ( Figs. 1, 7, 9 ); peristome slightly prosocline, ~ 10% in relation to longitudinal axis ( Figs. 2, 4 ); outer lip straight in middle, curved in both ends; anterior edge rounded; inner lip relatively similar to outer lip, attached to last whorl only in its superior third, sometimes producing low callus ( Figs. 1, 9 ), sometimes planar ( Fig. 7 ). Umbilicus opened ( Fig. 4 ), protected on right side by middle region of inner lip ( Figs. 1, 7, 9 ). Immature specimen bulimuliform ( Figs. 11 , 24 ).

Figures

Figure 30. Map of Brazil with states outlined. Bahia indicated by“BA”, with indication of places of occurrenceof Stapafurdius glaber sp.nov.(1 = Ituaçu) and of S.costierus sp.nov. (2 = Ubiraitá).

Figures 1-12. Stapafurdius glaber sp. nov., shell of types.(1-6) Holotype MZSP 154048 (L 10.5 mm). (1) frontal view. (2) right view. (3) dorsal view.(4) inferior view.(5) protoconch and first teleoconch,profile,scale = 1 mm.(6) apical view.(7-8) paratype MZSP 154047#1 (L 10.2 mm),frontal and dorsal views.(9-10) paratype MZSP 153803#1 (L 11.0 mm): frontal and dorsal views. (11-12) paratype MZSP 154047#3, immature shell (L 7.5 mm), (11) frontal view. (12) detail of protoconch and first teleoconch whorl,profile,scale = 1 mm.

Figures 24-29.Stapafurdius gen. nov.young shell SEM images.(24) S.glabersp.nov.paratype MZSP 154047,whole dorsalview,scale = 1 mm.(25) same,detail of apical region,dorsal-slightlyapical view,scale = 500 µm.(26)same,detail of transition protoconch-teleoconch,scale = 100 µm.(27) S.costiferus sp. nov.paratype MZSP 153882,whole dorsal view,scale = 1 mm.(28) same,detail of apical region,dorsal-slightly apical view,scale = 500 µm.(29)same,detail of protoconch and first teleoconch whorl,scale = 200 µm.