New species, misidentifications and problematic taxonomy of some Atlantic South American marine mollusks: a review Author Simone, Luiz Ricardo L. text Papéis Avulsos de Zoologia 2024 2024-08-09 64 1 104 https://doi.org/10.11606/1807-0205/2024.64.031 journal article 10.11606/1807-0205/2024.64.031 1807-0205 14705562 Superfamily Olivoidea Family Olividae Genus Agaronia Gray, 1839 Agaronia sterica new species ( Figs. 13-14 ) https://zoobank.org/ 31899908-C9BC-451E-AAF2-F6D62F828E37 Agaronia steeriae : Morretes, 1949: 101 ; Rios, 1970: 102 (pl. 32); Teso & Pastorino, 2011: 24 (in syn of O. carcellesi ) (non Reeve, 1850). Olivancillaria steeriae : Rios, 1975: 110 (pl. 32, fig. 465), 1985: 110 (in syn of O. vesica ), 1994: 142 (in syn of O. vesica ), 2009: 270 (in syn of O. vesica ); Oliveira et al., 1981: 223 ; Teso & Pastorino, 2011: 24 (in syn of O. carcellesi ) (non Reeve, 1850). Olivancillaria cf. carcellesi : Teso & Pastorino, 2011: 25 (fig. 15G, H, J) (non Klappenbach, 1965). Types: Holotype MZSP 166100, ♀ . Paratypes : MZSP 36498, 1♂ from type locality. BRAZIL . Espírito Santo ; Vitória, Praia da Guarderia ( Praia Comprida ), 20°18′24″S 40°17′07″W , MZSP 51042, 3 shells (Castro col., o.t., xii.1974 ); Guarapari, off, 20°54′12″S 40°07′55″W , 50-60 m , MZSP 69465, 2 spm (Femorale #18772, o.t., vii.2005 ). Rio de Janeiro ; Campos dos Goytacazes, off Cabo de São Tomé, 22°05′02″S 40°45′10″W , 30-40 m , MZSP 73374, 3 shells (Femorale, o.t., ix.2000 ); Cabo Frio, off, 22°55′30″S 41°57′44″W , 30-40 m , MZSP 68586, 15 spm (Femorale #21803, o.t., ix.2005 ). Type locality: BRAZIL . Espírito Santo ; Meaípe, off Meaípe, 20°46′32″S 40°31′35″W , 20-25 m [o.t., x.1993 ]. Diagnosis: SE Brazilian species generally with 35-40 mm , slender. Color uniform brownish grey to spotted brown on beige base. Spire short, bluntly angled. Aperture narrow, with narrow callus; inferior half of inner lip weakly folded obliquely. Radula with rachidian wide, with samesized central cusps. Description: Shell ( Figs. 13 , 14 A-B) up to 50 mm . Fusiform, lateralized; ~2.0-2.2 times longer than wide; spire~20% of total length, last whorl ~93% of total length. Spire angle ~70°. Spire up to 4 plane whorls; suture pane, only seen by narrow furrow. Protoconch of ~2 smooth, glossy whorls, ~ 1.8 mm , white ( Fig. 13E ); profile blunt ( Fig. 13 G-K), slightly pointed ( Fig. 13 A-D, L-M) or mamillated ( Figs. 13 O-P, 14A-B). Shell surface smooth, glossy, weak growth lines. Color siphonal slope always brown, with narrow ( Fig. 13J, K ), to wide middle spiral white band ( Fig. 13H, P ), sometimes absent ( Fig. 13D ); remaining body whorl variating from uniform gray ( Fig. 13 B-D), predominantly gray with some beige ( Fig. 13L, N ), basic light beige with brown drizzle denser ( Figs. 13J, K, P , 14B ), or sparser ( Fig. 13H ); spire variating from brown ( Fig. 13D ), beige ( Fig. 13 G-K), light beige ( Fig. 13P ), to bicolor ( Figs. 13N , 14B ). Aperture elongated, ~4-times longer than wide; superior end continuing with sutural narrow furrow. Canal widely opened, of ~40% of last whorl width. Outer lip simply arched. Inner lip white, weakly concave, almost straight; callus relatively thick in larger specimens ( Figs. 13A, B, O , 14A ), located in superi- or region, sometimes covering part of spire; sometimes white ( Fig. 13O ), sometimes with brown spot ( Fig. 13S ); callus narrowing in middle level of inner lip; inferior half of inner lip with set of ~10 oblique narrow, relatively uniform folds, located close from each other ( Fig. 13C, M ); superior fold usually larger than others,groove as inferior limit of this set of folds, ending in anterior blunt beak (Fi gs. 13B, C, G, I, L, M, O, 14A). No umbilicus. No operculum. Head-foot entirely retracted inside shell ( Fig. 13A, G, I ). Head small, marked by small pair of cephalic flaps ( Fig. 14E : cp); eyes and tentacles absent. Foot very wide and ample ( Fig. 14G : ft); anterior edge covered by well-developed propodium ( Fig. 14E, G : pr), laterally expanding in pair of small, pointed lateral projections ( Fig. 14G : fl). Mandle edge relatively thick, unpigmented ( Fig. 14C, E : mb); pallial tentacle ( Fig. 14E, F : pt) located in posterior end of mantle edge; basal region broad, tapering gradually up to pointed tip. Pallial cavity rather triangular, lateral positioned, gill ( Fig. 14D : gi) and osphradium located in left side; wide pallial gonoducts in right side). Rhynchostome pore-like, located between and ventral to cephalic flaps. Radula ( Fig. 13 H-I) rachidian ~40% of radular width; ~3 times wider than long; base chevron-like, posterior arched, concave; cutting edge with 3 central, tall cusps, divergently positioned, median cusp slightly smaller than lateral cusps;single very small cusps in base of lateral cusps; remaining marginal rachidian third as flattened, simple weakly arched rod. Lateral teeth with wide base (~50% of rachidian width), abruptly tapering up to hooklike terminal tip, tuned inside. Pallial oviduct occupying ~ ⅓ of pallial cavity, round- ed; displacing rectum and anus to left, anus aperture away from right corner ( Fig. 14D : an). Bursa copulatrix spheric, located in middle level of pallial oviduct posterior edge ( Fig. 14D : bc); bursa duct (bd) wide, running transversely along oviduct ventral wall dividing oviduct approximately in half, up to region close to anus. Penis filiform, very elongated ( Fig. 14E : pe), inserted at some distance posterior and at right from cephalic flaps, tapering very gradually; tip bluntly pointed; penis duct entirely closed (tubular), opening at tip. Figure 13. Agaronia sterica shells of some type specimens showing variation:(A-F) Holotype MZSP 166100(L 48.2 mm);(A) frontal view with specimen still inside; (B)frontal view;(C) right view;(D) dorsal view;(E)apical view;(F) anterior view;(G-H) paratype MZSP 68586#1 (L 33.8 mm),frontal and dorsal views;(I-J) 68586#2 (L 34.8 mm), frontal and dorsal views; (K) paratype MZSP 69465 (L 40.0 mm), dorsal view; (L-M) paratype MZSP 73374#1 (L 46.9 mm): frontal, right and dorsal views;(O-P) paratype MZSP 51042 (L 49.3 mm),frontal and dorsal views. Etymology: The specific epithet is the nickname of the species when the Brazilian population was called "steeriae ", a joking related to the name hysterical, related to the confusion with the African species, and the lability of shell colors. Figure 14. Agaronia sterica shell and anatomy of type specimens:(A-B) shell of paratype MZSP 73374#2 (L 31.0 mm),from Rio de Janeiro,frontal and dorsal views; (C) holotype head-foot and part of adjacent pallial region, dorsal-slightly right view; (D) same,right region of pallial cavity, ventral-inner view,specially showing pallial oviduct; (E) paratype MZSP 36498, anterior region of head-foot and adjacent pallial cavity, anterior-slightly right view, penis displaced from pallial cavity and deflected downwards; (F) same,detail of posterior region of mantel edge,showing pallial tentacle;(G) paratype MZSP 68586,entire specimen extracted from shell,ventral view,foot unfolded and expanded.Scales:= 2 mm.(H-I) radulae in SEM,middle region (MZSP 69465), scale:= 100 µm. Lettering:an,anus;bc,bursa copulatrix;bd, bursa duct;cm,columellar muscle;cp,cephalic flaps;fl, foot lateral projections;fs,foot sole;ft, foot;gi,gill; ki,kidney;mb, mantle border;ov,pallial oviduct;pe,penis;pr,propodium;pt, pallial tentacle;py,pallial cavity,si,siphon;vm,visceral mass. Distribution: Espírito Santo and Rio de Janeiro coasts.