Notes on Kora and description of a new species from Minas Gerais, Southeast Brazil (Mollusca: Gastropoda: Stylommatophora)
Author
Pena, Meire Silva
Laboratório de Malacologia, Museu de Ciências Naturais da Pontifícia Universidade Católica de Minas Gerais.
meirepena@yahoo.com.br
text
Zoologia
2024
e 23059
2024-05-10
41
1
11
http://dx.doi.org/10.1590/s1984-4689.v41.e23059
journal article
10.1590/S1984-4689.v41.e23059
1984-4689
13176730
76D4BFC5-CABA-4972-A30E-0DD7C42C501A
Kora rupestris
Simone
&
Salvador
, 2016
Holotype
:
Museu de Zoologia
,
Universidade
de
São Paulo
(
MZSP
)
HTMZSP 12412
;
Paratypes
:
MZSP 12
.441.
Type locality:
Brazil
,
Bahia
, Carinhanha (
Salvador
and Simone 2016
).
Diagnosis:
Kora rupestris
was distinguished from
K. corallina
by protoconch sculpture and thinner profile (
Salvador
and Simone 2016
).
Salvador
and Simone (2021)
featured
K. rupestris
shells from
PARNA
Cavernas do Peruaçu, which we describe herein as a new species based on evidence from the morphology of the shell and the soft part.
Redescription: shell (
Fig. 2A–I
) conical-fusiform, brown in color (Küppers N
30
A
80
M
50
) with slightly darker body whorl (Küppers N 80 A 50 M 50) and lighter narrow subsutural band (Küppers N 10 A 50 M 20). The studied material contains a morphotype with a darker color pattern (Küppers N
70
A
40
M
40
) in all whorls but maintaining the lighter subsutural band (Küppers N
40
A
50
M
30
) (
Fig. 2B, D
). Protoconch (
Fig. 2G–I
) with two whorls, and a wide and flat core; first whorl smooth, second with delicate discontinuous axial grooves. Teleoconch with wider and straighter grooves than the protoconch. Suture non-crenulated. Aperture oval, slightly inclined relative to columellar axis; columellar axis (
Fig. 2E–F
) not lamellar. Peristome deflected, wide and with clear columellar lip (Küppers N 20 A 30 M 10); parietal lip not thickened. Dimensions (in mm, n = 30 shells): H = 42.20–48.00; W = 19.45–24.80; ah = 22.95–18.40; aw = 4.00–12.85; wn = 7 ¼.
Figure 1. (A) PARNA Cavernas do Peruaçu map: (B–C) landscape; (D)
K. rupestris
live specimen.
Softs parts (
Fig. 3A–F
): cephalopedal mass dark gray (Küppers N
70
A
40
M
10
) with grooves forming a reticulated surface on the dorsum and light gray (Küppers N 60 A 40 M 10); ventral region with smooth surface. Genital pore below right ommatophore. Mantle edge, in ventral view, (
Fig. 3B
) thick, with wide and continuous external lobe, with acuminate angle at end that accommodates the pneumostome. Inner lobe with three thin flaps partially detached from outer lobe one flap adjacent to pneumostome, second extending from pneumostome to median region, third extending from median region to opposite end of pneumostome. Pneumostome circular, flanked by anal slit. Pallial roof, in ventral view (
Fig. 3A
), with translucent surface with dense embossed venation between edge of secondary ureter and median region of mantle edge. Pulmonary vein anteriorly branched, connected by numerous perpendicular and branched vessels from mantle edge to pericardial cavity. Transverse venation extending to bottom of pallial cavity between kidney and rectum. Kidney elongated, triangular with the most acuminate apex passing through the pericardium. Primary ureter as a lighter band attached to side of kidney; secondary ureter fully closed, running lateral to rectum. Pericardial sac partially opaque, tapered at both ends.
Figure 2.
Kora rupestris
: (A–B) frontal view; (C–D) dorsal view; (A–C) medium brown morphotype; (B–D) dark brown morphotype; (E–F) collumelar axis without extra lamellae; (G–I) protoconch. Scale bars: A–F = 5 mm, G = 500 µm, H = 1 mm, I = 200 µm.
A
Figure 3.
Kora rupestris
: (A) pallial roof; (B) mantle edge; (C) digestive system; (D) reproductive system; (E) detail showing the fertilization complex; (F) detail showing the vas deferens at the penial complex. (BB) buccal bulb, (BC) bursa copulatrix, (BD) bursa duct, (FC)fertilization complex, (HD) hermaphrodite duct, (IL) inner lobe, (Ki) Kidney, (OL) outer lobe, (OV) ovariotestis, (Ovd) oviduct, (Pe) pericardium, (Pn) pneumostome, (Pr) prostate, (PS) penial sheath, (PV) pulmonary vein, (RE) rectum, (RN) radular nucleus, (SG) salivary glands, (ST) stomach, (VD) vas deferens. Scale bars: 2 mm.
Digestive system: jaw (
Fig. 4A
) arched, comprising 17 folds of non-uniform widths, central four narrower than distal folds. Radula (
Fig. 4B–C
): with rows of approximately 102 monocuspid teeth of regular size and shape, without distinction between central, lateral, and marginal teeth. Teeth narrow with long base and free end curved like a hook and slightly pointed; free end of each tooth with an elongated concavity (visualized under higher magnification. Digestive tube (
Fig. 3C
): buccal bulb with very prominent radular nucleus that is slightly curved upwards. Esophagus diameter wider at crop. Salivary glands latero-basal; each gland with only one duct departing towards dorsal region of buccal bulb where it penetrates each side of the point of junction with the esophagus. Posterior esophagus equal in diameter to stomach. Stomach tubular, recurved, with delicate translucent walls.
Reproductive system (
Fig. 3D–F
): ovariotestis with single grouping of finger-like follicles with darker distal ends that internally fill digestive gland between third and fourth turn of the visceral mass; delicate tubules depart from various points of the grouping, which, reuniting near distal end of the gonad, form the hermaphrodite duct. Hermaphrodite duct undergoes great thickening, greater pigmentation and becomes coiled reaching ventral face of albumen gland connecting to the fertilization complex. Fertilization complex (
Fig. 3E
) elongated, tubular, with circular fold at mid-length that directs it upwards; second fold directs blind end forward. Albumen gland voluminous, translucent, short, and widely connected to ovispermoduct. Ovispermoduct long, twisted, uterus walls forming transverse folds throughout its extension. Prostate surface granular, adhered to uterine wall from albumen gland to just before oviduct bifurcation with bursa copulatrix duct. Bursa copulatrix duct originates in the oviduct just below vas deferens exteriorization; diameter constant for approximately 1/5 of its course, dilating slightly, narrowing again for last 1/5 of its course to encounter the bursa. Bursa copulatrix oval; vagina length equivalent to less than half of that of free oviduct. Vas deferens (
Fig. 3F
) emerging in oviduct just above bursa copulatrix duct bifurcation, descending towards penial complex, passing below muscular sheath of phallus, running externally through phallus and epiphallus, penetrating its limit with flagellum. Penial complex long, tubular, with three convoluted folds along its course; next to the vagina it has a muscular sheath corresponding in length to that of the oviduct. Phallus practically constant in diameter, slightly tapering distally; no external distinction from epiphallus; flagellum short, terminally attached to retractor phallus muscle.
Material examined:
Brazil
,
Minas Gerais
, Itacarambi,
PARNA
Cavernas do Peruaçu
,
Fazenda
ICIL
Volta da Serra
,
Col. Mol.
MCNPUC 301 (
22 specimens
preserved in ethanol), 13
December
, 2010,
M.S. Pena
, A.
Suhett
,
D.C. Souza
cols. I
;
PARNA
Cavernas do Peruaçu
,
Estrada Fazenda Sr Odilon
,
Col. Mol.
MCN
PUC 575
(
10 specimens
preserved in ethanol),
December
, 2022, J.S.
Silva
,
M.S.Pena
,
I.Santos Silva
cols
.;
PARNA
Cavernas do Peruaçu
,
ICIL
,
Volta da Serra
,
Col. Mol.
MCNPUC 249 (51 shells),
December 2010
,
M.S.Pena
,
A. Suhett
,
D.C.Souza
, cols
.