Macrocypraea Schilder 1930
Creators: name: Simone, Luiz Ricardo L.
name: Cavallari, Daniel C.
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Littorinimorpha
Cypraeidae
Macrocypraea

description: Genus Macrocypraea Schilder, 1930.
Macrocypraea Schilder, 1930: 55. Lorenz, 2071[2]: 286.
Type species: Cypraea exanthema Linné, 1767 (= M. zebra (L., 1758) see [10, 11]) by original designation. Recent, Western Atlantic.
Macrocypraea mammoth sp. nov .. (Figs 2 and 3F, 3L–3M and 4–7)
urn:lsid:zoobank.org:act: B76C5BC6-595A-4782-A706-6A2BBF1D718F
Cypraea zebra: Rios, 1987[12]: 59 (partim) (non Linnaeus, 1758).
Cypraea (Macrocypraea) zebra: Leal, 1991[13]: 99; Rios, 2009[14]: 123, text figure. (partim) (non Linnaeus, 1758).
Macrocypraea zebra dissimilis: Lorenz, 2017[2]: 289, text figure., pl. 59 (partim) (non Schilder, 1924).
Type specimens. Holotype ♀, MZSP 137544. Paratypes: BRAZIL: off EspÍrito Santo; Trindade Island: Praia dos Cabritos, MNRJ 5059, 1 shell (B. Prazeres col., xii.1975 - ii.1976), Calhaus / Farrilhões, MNRJ 5056, 1 shell (J. Becker & A.B. Costa col., 1965, sta. D248/966), Calheta, MZSP 108077, 20 ˚30’37.6”S 29˚18’28.1”W, 1 shell (J.B. Mendonça col., 12.vi.2012), MZSP 137545, 20 ˚30’29.5”S 29˚18’37.0”W, 16.3 m, 1 ♂, MZSP 137546, 1 ♂ (shell now broken) (J.B. Mendonça col., 9.vii.2015).
Type locality. BRAZIL, off Espírito Santo state, Trindade Island, Secon / GCIT, 20˚ 30’20.9”S 29˚18’43.7”W, 11.6 m (J.B. Mendonça col., 9.vii.2015).
Diagnosis. Shell large, solid and heavy. Posterior ending tapered and long, base slightly inflated. Anterior end flattened, projected, flanking both sides of siphon. Color pattern with large, scattered beige spots, most basal of which presenting dark brown central area. Teeth of inner lip slope long, close from each other, radially disposed, forming nodes preceding canal. Mantle papillae mostly bearing 3–5 small aligned distal projections. Osphradium elongated, with short posterior branch and narrow anterior branch. Odontophore protractor muscles (m1d) composed of single strong dorsal pair of bundles; ventral protractor pair (m10) with multiple branches. Seminal vesicle with uniform width along its length; pallial sperm groove with similar-sized edges. Penis with clear glandular region. Bursa copulatrix bearing long duct, sac-like, with thin-walled terminal region.
Description
Shell (Figs 2–4). Large (95–133 mm), inflated, antero-posteriorly elongated, solid and heavy, with tapered anterior and posterior extremities, 1.8 times as long as wide, slightly taller (~10%) than wide (Figs 2A, 2G, 2K, 3A and 4H). Surface glossy, color light to dark brown,
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with lighter-colored longitudinal median dorsal line (usually dislocated to right), and scattered rounded beige spots; spots near base usually larger, some with dark brown (ocellated) central area (Fig 2C, 2I and 2M). Basal area usually lighter colored, especially around aperture, with dark brown labral teeth (Figs 2B, 2I, 2J and 3B); younger individuals ground color yellowish, with wide orange transverse stripes dorsally (Fig 3E and 3F). Aperture slit-like, long and narrow, becoming progressively wider toward anterior end (Figs 2B, 2H, 2J and 4F); width ~12– 15% of shell width. Inner lip glossy, bearing 35–42 strong labral teeth, each individual tooth sometimes branching into 2–3 narrower teeth towards interior of aperture; inner slope full of narrow, transverse teeth, radially disposed (virtual focus above middle region of dorsal shell surface; Fig 4J); anterior plate relatively deep concave, tall (~half local height), ventral end of more anterior teeth strongly nodose, with a node at base of ventral-left siphonal edge (Fig 4J). Outer lip bearing 34–41 strong labral teeth. Canal flanked by pair of spatulate long projections (Figs 2E and 4G), length ~1/6 of remaining shell length (Fig 4F) relatively horizontal positioned (Fig 4J and 4K). Shell walls relatively thick (Fig 4G, 4J and 4K).
Shell variation relatively small. Size normally over 130 mm, but some rare specimens are about 90 mm. pale spots usually small, uniformly splayed (Fig 2A, 2G and 2K), but sometimes spots larger (Fig 3A, 3C and 3D). Ocellated spots usually visible in right side (Figs 2C, 2I, 2M and 3C), rather than left side (Fig 2D and 2L), with exceptions (Fig 3D).
Head-foot (Figs 5A and 6A). Exposed areas homogeneous dark grayish-brown. Proboscis cylindrical, large, occupying ~70% of haemocoel volume (Fig 6A). Cephalic tentacles long, origin located approximately at ventral lateral surface of snout base (Fig 5A: te); proximal half distinctly broader than distal half. Anterior furrow of pedal gland (pg) well-developed. Columellar muscle (cm) short (~half whorl long), thin distally. Anterior projection of head solid-muscular (Fig 5A: ar), originating in nuchal region, bending toward anterior region, located at left of siphonal canal. Accessory muscle of columellar muscle running along right edge of main muscle, attached to pallial cavity, right margin gradually fading (Fig 5B: pm). Haemocoel relatively broad, elliptical. Haemocoel connection with visceral mass (esophageal and aortic passage) located at middle level of left margin of haemocoel (Fig 6A). Two pairs of small retractor muscles of proboscis (Fig 6A: rm) originating in ventro-lateral middle region of haemocoel, bordering lateral haemocoel inner surface towards anterior region, inserting along ventral and lateral wall of proboscis; median pair larger than remaining counterparts.
Mantle organs (Fig 5B). Mantle border very large, broad, with left and right lobes (rl) exceeding shell aperture, covering shell completely during activity. Outer surface of exposed part of mantle dark grayish-brown in color (Fig 3M), bearing several uniformly distributed papillae (mp), except for anterior and posterior regions. Each papilla with base narrower than its middle region, profile broad, rather cylindrical, narrowing distally, with 3–5 transversallyaligned small terminal projections. Siphon small (si) distinctly separated from mantle border, shallow, lacking marginal papillae. Anal siphon (as) also separated from mantle border, slightly shallower and locaded on opposite side of incurrent siphon. Osphradium (os) occupying ~1/ 15 of pallial cavity roof, relatively large, located at some distance from siphon. Osphradium with 3 branches; anterior branch turned forward toward siphon, length ~70% of osphradium length, narrow, pointed; right branch similar to anterior branch, but slightly broader and shorter; left branch with ~1/3 of anterior branch length, distal end blunt, rounded. Each osphradium branch bipectinate, each filament low and thin, its base almost fully connected to mantle, except for rounded tip bent externally. Osphradium ganglion thick, running along central region of each branch. Distance between osphradium and gill equivalent to osphradium width. Gill (gi) occupying ~1/3 of pallial cavity roof, long, strongly curved (concavity located to left), surrounding osphradium. Ctenidial vein relatively broad, width homogeneous along its length; connection with auricle sub-terminal (Fig 5B: au) (described below). Each gill filament tall, triangular, tip long, slender and sharp (Fig 5B). Distance between gill and visceral mass narrow in posterior half, successively far from visceral mass and rectum in anterior half. Hypobranchial gland very developed (hg), thick, white; occupying area between gill and
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rectum in anterior 2/3 of pallial roof. Hypobranchial gland supported by transverse, thin septa originating from adjacent mantle. Rectum relatively broad, running along right margin of cavity. Anus siphoned, located close to anal siphon. Genital gonoducts running ventral and at right from rectum, most in floor of pallial cavity (details below).
Visceral mass (Figs 5B and 6C). Relatively small, ~3 whorls posterior to pallial cavity. Right anterior region more anterior than left one for ~1/2 whorl, invading pallial cavity. Gonad (ts) occupying from second whorl up to pericardial region, surrounding digestive gland on columellar side. Stomach with adjacent esophagus and intestine obliquely occupying central region of first visceral whorl. Digestive gland (dg) dark brown, filling space between stomach (and adjacent digestive tubes) and gonad, being more massive anteriorly to stomach in last visceral whorl. Kidney (ki) and pericardium as anterior border of digestive gland.
Circulatory and excretory systems (Fig 6C). Heart relatively large, located in anteriorleft region of visceral mass (Fig 5B). Auricle elongated, narrow, connecting with ctenidial vein at about ~1/10 before its posterior end, running immersed in mantle, crossing obliquely and dorsally to gill (Fig 5B: au), running about equivalent distance inside pericardial cavity, becoming slightly broader toward its insertion in ventricle. Ventricle large (ve), walls thick muscular. Aortas running attached to left pericardial wall, anterior aorta (aa) ~3 times broader than posterior aorta, running parallel to esophagus. Anterior aorta within haemocoel easily visible up to buccal mass (Fig 6A: aa). Kidney narrow, long, located in central and right regions of posterior limit of pallial cavity (Fig 5B). Kidney chamber mostly hollow, intestine running along its dorsal inner surface, digestive gland located in its posterior limit. Kidney lobe (kv) single, as solid glandular mass in right-anterior region of kidney, attached to adjacent intestine; gradually becoming flattened mass attached to membrane between kidney and pallial chambers. Nephridial gland triangular (ng), occupying ~1/4 of kidney inner space, transversely folded; central vessel well-developed (ns), running on right side, ventral to nephrostome. Nephrostome (ne) as broad, transverse slit in left region of membrane between kidney and pallial cavity (km), close to pericardium.
Digestive system (Figs 6B–6D and 7B). Proboscis very long, almost as long as haemocoel, occupying ~70% of haemocoel volume (Fig 6A: pb). Buccal mass occupying ~1/2 of haemocoel volume. Oral tube relatively long, broad, thickly muscular (mj), presenting several muscle layers in different dispositions (Fig 7B: ot). Differentiable jaws absent. Pair of dorsal folds of buccal cavity (df) very wide, with very narrow furrow separating folds in median line; dorsal folds becoming separated from each other at their middle level, showing series of narrow, longitudinal folds in this region, running in posterior direction longitudinally (Fig 7B: ff), flanked by pair of taller folds (ef), running up to esophageal gland. Odontophore muscles (Fig 6B and 6D): m1d) pair of narrow jugal muscles working as dorsal protractor muscles, relatively flattened, originating in anterior-dorsal surface of mouth, close to median line, running in posterior direction, inserting in posterior end of buccal mass; mc) buccal sphincter and circular muscles, relatively thin, inconspicuous; mj) jaws, oral tube and peri-buccal muscles, portion connected to odontophore working as odontophore protractors, inserting in posterior-ventral region of odontophore cartilages (Fig 6D: mj); m2) pair of broad dorsal retractor muscles of buccal mass, originating in ventral-posterior region of inner surface of haemocoel, originating in same of origin of pair of retractor muscle of proboscis (rm) (Fig 6A: m2), running towards anterior region, attached to lateral surface of esophagus, inserting in lateral-dorsal-posterior surface of buccal mass; m3) narrow and very thin pair of muscles, originating in lateral-ventral region of posterior odontophore surface, running dorsally, covering posterior region of odontophore, inserting in dorso-posterior region odontophore close to esophageal origin (Fig 6D: m3); m4) large pair of dorsal tensor muscle of radula, originating around origin of mj, broad at origin, running toward dorsum, covering entire inner odontophore structures and cartilages, inserting as two flaps, medial flap smaller (Fig 6D: m4a) connecting directly to radular ribbon, lateral flap broader (Fig 6D: m4), connecting laterally along subradular cartilage; m5) large pair of secondary dorsal tensor muscle of radula (Fig 6D: m5), originating in medianposterior region of m4, close to median line, running toward anterior region of odontophore for relatively short distance (1/3 odontophore length), inserting in shorter region of ventral surface of radular sac, just ventrally to insertion of m4; m6) horizontal muscle, relatively thin, connecting anterior-ventral margin of both odontophore cartilages for about 1/4 of their length; m6a) accessory horizontal muscle, same function and same size as m6, but located behind it at distance equivalent to half its length (Fig 6D: m6, m6a); m7) absent; m10) pair of ventral protractor muscle of buccal mass, originating in ventral and lateral regions around mouth, very broad and thick at origin, running toward posterior and medial regions of odontophore, becoming narrow and thin at insertion, inserting in postero-ventral level of odontophore (Fig 6B: m10); m11) narrow pair of ventral tensor muscles of radula (Fig 6D: m11) and auxiliary ventral protractor muscle of buccal mass (Fig 6A and 6B: m11), originating in middle ventral region of inner surface of haemocoel near origin of retractor muscle of proboscis (rm), running towards anterior region of odontophore, dorsally to rm, penetrating into ventro-posterior region of odontophore near radular sac (Fig 6B), running further anteriorly, flanking m6 and m6a, inserting in anterior end of radular ribbon; m12, m13) absent; m14) pair of accessory ventral protractor muscle of buccal mass, slightly thin, same origin as m10 but medial, running in posterior direction, covering m10, gradually becoming narrower, inserting in posterior limit of odontophore on m4 (Fig 6B). Pair of odontophore cartilages long, flattened, somewhat elliptical, most of muscles inserted on their outer surface (Fig 6D: oc). Radula long, about 3 times odontophore length (Fig 6A: rs), coiled behind buccal mass inside haemocoel.
Radula. (Fig 4A–4C): rachidian tooth ~1/6 of width of radular ribbon, central cusp broad, length ~1/2 of rachidian length, blunt, curved inwards, bearing pair of very low secondary cusps opposed to central cusp (Fig 4B); lateral tooth as wide as rachidian, flattened, curved inwards and medially, tip acute, carinated at periphery, slightly arched, base flattened, bearing very small secondary cusp at base of lateral edge of main cusp; inner marginal tooth similar to lateral tooth, but slightly narrower; outer marginal tooth similar to inner marginal tooth, but ~40% narrower and lacking lateral secondary cusp. Salivary glands clustering around anterior and middle esophagus, behind nerve ring (Fig 7B: sg), located at left-middle region of haemocoel (Fig 6A). Salivary ducts passing through nerve ring; penetrating in dorsal wall of buccal mass, running immersed along base of dorsal folds; opening at middle level of dorsal folds, near and bent toward median line (Fig 7B: sa). Anterior esophagus somewhat narrow, inner surface with pair of tall longitudinal folds (as extension of dorsal folds of buccal mass) (ef), flanking series of longitudinal folds (Fig 7B: ff). Middle esophagus broad, smooth; ventral esophageal gland massive, broad, well delimited, located in posterior-right region of haemocoel (Fig 6A: ec); inner surface of esophageal gland entirely filled with several thin septa, bearing fragile glandular tissue (Fig 7B: ec). Posterior esophagus narrow (Fig 6A and 6C: es), long (about half of total esophagus length), inner surface lacking folds. Posterior esophagus located inside visceral mass, gradually becoming broader, with smooth inner surface (Fig 6C). Stomach large (Fig 6C), u-shaped, located around penultimate whorl of visceral mass (Fig 6C: st); esophagus inserting on its left side with no clear distinction. Duct to digestive gland (Fig 6C: dd) located at transition between esophagus and stomach, almost as broad as esophagus,
curved anteriorly, bearing series of transverse small folds along its ventral region; septa ending in duct bifurcation, at considerable distance from their origin. Intestine broad at origin, identifiable as right branch of stomach; running in anterior direction and leftward, parallel to posterior esophagus (Fig 6C: in); inner surface smooth. Digestive gland described above. Intestine, suddenly becoming bent rightward around left end of kidney, running attached to posterior surface of kidney along its entire length, crossing from left to right side of visceral mass anterior limit (Fig 6C). Rectum short, running along right margin of pallial cavity. Anus broad, siphoned, located close to anal siphon of mantle border (Figs 5B and 6C).
Genital system. Male. Testis running along columellar surface of visceral mass up to posterior limit of pallial cavity (Fig 5B: ts). Seminal vesicle intensely coiled, located in anterior projection of visceral mass, at left of esophagus, as extension of testis (Fig 5B: sv). Seminal vesicle with about same caliber along its length. Vas deferens suddenly running perpendicularly in anterior direction along approximately half of visceral mass width (Fig 5B: vd), in middle region of right surface of seminal vesicle mass; small aperture to sinus located in region preceding its exit to pallial cavity (Fig 7C: vd). Opened sperm grove beginning at its exit to pallial cavity floor (Fig 7C: ps), running up to penis base (Figs 5A and 7C), flanked by relatively thick, symmetrical edges. Penis long, with ~1/2 of head-foot length, almost cylindrical, curved distally (Figs 5A and 7C: pe). Penis groove running along its ventral surface up to penis tip. Penis tip bearing small, broad papilla. Penial gland located in middle region of right edge of penis (Fig 7C: pl), disform, occupying ~1/3 of penis surface.
Female (Fig 7A and 7D). Ovary occupying approximately same regions than testis of males, but broader posteriorly and very narrow anteriorly (Fig 7A: oy). Visceral oviduct (vo) running to right, in ventral surface of kidney. Visceral oviduct very slender, short, with ovarian tissue along its length (Fig 7A). In left half of visceral mass oviduct suddenly expanding, becoming thick glandular. Albumen gland of pallial oviduct (ag) with pair of glandular laminas, similarly sized, gradually increasing along its length. Bursa copulatrix (bc) balloon-shaped, located in middle level of pallial oviduct, insertion right; duct thick walled, as long as local pallial oviduct width, inner surface with 7–8 longitudinal simple folds (Fig 7D: bc). Bursa main region wide, with 4–5 spherical lobes, about as wide as local oviduct; walls thin, inner surface smooth (Fig 7D). Bursa orifice located just between both laminas of pallial oviduct. Female genital aperture (ap) as simple longitudinal slit, close to floor of pallial cavity far behind anus; edges thick.
Central nervous system. Nerve ring similar to those of remaining species. Degree of fusion of both cerebral ganglia high, almost resulting in single spherical mass. Cerebro-pedal and cerebro-pleural connectives very long, 5–6 times longer than both cerebral ganglia width.
Distribution. Known only from Trindade and Martim Vaz Islands.
Habitat. Rocks and corals, subtidal, ~ 20 m depth (Fig 3L and 3M).
Etymology. The specific epithet is in apposition; it is a reference to mammoths, which are widely recognized for their huge size and heavy build, an allusion to the large proportions and heavy shell of new species. Moreover, the long anterior projections of the shell are reminiscent of a mammoth’s tusk. The epithet also follows the tendency of naming Macrocypraea ’s after animals.
Measurements (respectively length, height, width in mm). Holotype: 133.1 by 54.6 by 72.4; MZSP 108077: 95.8 by 46.7 by 54.9; MZSP 104754: 116.7; MZSP 108079: 74.1 by 32.6 by 41.1; MZSP 108084: 111.6; MZSP 108095: 114.9 by 56.6 by 65.9. MZSP 101404: 88.7 by 37.1 by 47.4; MZSP 108054: 103.3 by 46.7 by 55.3; MZSP 118452: 111.7 by 49.5 by 60.4. MZSP 121946: 120.1 by 53.1 by 65.0.
Material examined. Types. Additional material: BRAZIL. off Espírito Santo; Trindade Island, MNRJ 30770, 30771, 30772, 35142, 4 shells (Bruno Lobo col., 1916), Praia dos Cabritos (Cabritas), MNRJ not numb., 1 shell (A Coelho col., 31.x.1957), MNRJ 5055, 2 shells (L.S.Silva
& J. Becker col., i.1966), MNRJ 5058, 3 shells (J. Becker col., xii.1958), MNRJ 5054, 1 shell (S. Ypiranga, A Coelho & J Becker col., x.1957), MZSP 108079, 1 subadult shell, 20˚29’38.2”S 29˚ 19’50.2”W, 10 m (J.B. Mendonça col., 12.vi.2012), MZSP 108054, 1 shell (J.B. Mendonça coll., 17/vi/2012), Praia da Tartaruga, MNRJ 5057, 3 shells (J. Becker col., xii.1958), MZSP 101404, 1 shell+ 1 fragment (D. Abbate & P.O. Lima col., 25.vii.2011), MZSP 121241, 1 shell fragment (Simone et al col., 25.vii.2011), MZSP 104152, 1 subadult shell fragment (C.H. Guimarães col., 27.ii.2012), Calheta, MNRJ 5060, 3 shells (B. Prazeres col., xii.1975 - ii.1976), near local lighthouse, 20˚29 0 52.3 @ S 29˚19 0 15.6 @ W, 12.9 m, MZSP 118452, 1 shell (J.B. Mendonça coll., 17/iv/ 2012), 20˚30’26.1”S 29˚18’44.2”W, MZSP 108095, 1 shell (J.B. Mendonça col.), Praia do Monumento, 20˚30’10.3”S 29˚20’36.1”W, 15 m, MZSP 121496, 1 shell (J.B. Mendonça col., 2. xi.2014), Ponta Norte, 20˚29’18.7”S 29˚20’18.3”W, 10 m, MZSP 108078, 1 shell, MZSP 121237, 1 shell fragment (J.B. Mendonça coll., 03/vii/2012), between Calheta and Andradas Beach, 20˚ 30’37.9”S 29˚18’32.0”W, 10 m MZSP 104754, 1 fragmented shell, (C.H. Guimarães col., 14. ii.2012); Parcel das Tartarugas, 20˚31’01.3”S 29˚17’56.9”W, 5 m, MZSP 108084, 1 fragmented shell depth (J.B. Mendonça col., 11.vi.2012), Enseada Noroeste, 20˚29’40.9”S 29˚20’44.1”W, 12.2 m, MZSP 104744, 2 shell fragments (C.H. Guimarães col., 30.i.2012); Martim Vaz, 20˚ 28’28.42”S 28˚51’24.56”W, 21 m, 1 shell (J.B. Mendonça col., 21.vi.2015).
description: Published as part of Simone, Luiz Ricardo L. & Cavallari, Daniel C., 2020, A new species of Macrocypraea (Gastropoda, Cypraeidae) from Trindade Island, Brazil, including phenotypic differentiation from remaining congeneric species, pp. 1-26 in PLoS ONE (e 0225963) (e 0225963) 15 (1) on pages 4-15, DOI: 10.1371/journal.pone.0225963, http://zenodo.org/record/12630957