Radiation and decline of endodontid land snails in Makatea, French Polynesia
Author
Sartori, André F.
Author
Gargominy, Olivier
Author
Fontaine, Benoît
text
Zootaxa
2014
3772
1
1
68
journal article
36890
10.11646/zootaxa.3772.1.1
12787306-9151-40cd-8103-1ecac6bdb6b8
1175-5326
285653
1A1578DD-4B10-4F70-8CB6-03B0ED07AB68
Mautodontha
(
Garrettoconcha
)
temaoensis
sp. nov.
Figures 10
C; 13; 35H; 37E; 39.
Examined material
(
19 specimens
).
Holotype
:
MNHN
25685, Mk16.
Paratypes
:
MNHN
26533, 8 shells, Mk16.
Additional material
: 10 shells, Mk16.
Type
locality.
Road descending to Temao, Makatea (
15.82593°S
;
148.27534°W
). Lower side of the road below rocks. Limestone, alt.
10 m
; station Mk16.
Diagnosis.
Shell less than
3 mm
in diameter, depressed, without flammulations; teleoconch sculptured by broad, relatively well-spaced primary axial ribs (
<
90 ribs on body whorl); umbilicus V-shaped; palatal wall with 4 barriers; parietal wall with 3 conspicuous barriers.
Description.
Shell depressed, white, without flammulations. Shell wall thin, opaque; periostracum unknown. Apex and spire elevated; later whorls descending slightly more rapidly. Apical and umbilical sutures impressed; whorls flattened above rounded periphery and at columellar wall. Sculpture of protoconch and transition with teleoconch unknown. Primary axial sculpture of the teleoconch composed of broad, prominent ribs, with interspaces approximately three to four times their width, overlaid by a secondary axial sculpture of fine riblets, with interspaces c. 1–3 times their width. Umbilicus deep, V-shaped. Peristome subovate; columellar lip very slightly reflected. Palatal wall with 4 barriers, all extending c. 1/8 whorl, descending gradually anteriorly and somewhat abruptly posteriorly, approximately equidistant, recessed within the aperture; barrier 1 columellar or positioned at the junction of basal and columellar walls; barriers 2 to 4 basal in position; barriers 1 and 4 slightly less prominent and more deeply recessed than barriers 2 and 3. Parietal wall with 3 conspicuous barriers, all extending c. 3/16 whorl, descending somewhat abruptly anteriorly and gradually posteriorly, not recessed within the aperture, similar in prominence; interspace between barriers 1 and 2 slightly larger than that between 2 and 3. Other shell features that can be expressed numerically are shown in
Table 2
.
Remarks.
M.
(
G.
)
temaoensis
was represented in the samples by worn specimens. Hence, fine details of its sculpture are unknown. It resembles
M.
(
G
.)
occidentalis
in shell size but at a lower whorl count. Its raised, somewhat pointed apex resembles those of
M.
(
G.
)
makateaensis
sp. nov.
and
M.
(
G
.)
passosi
sp. nov.
, from which it differs in having more numerous aperture barriers, a less elevated spire, and a smaller size at the same whorl count. A subovate periostome and well-spaced primary sculpture are additional characters suggesting a close relationship between
M.
(
G.
)
temaoensis
and
M.
(
G.
)
makateaensis
.
Etymology.
From the port of Temao. This species is only known from the road descending to the port.