Research Article |
Corresponding author: Barna Páll-Gergely ( pallgergely2@gmail.com ) Academic editor: Menno Schilthuizen
© 2017 Barna Páll-Gergely, András Hunyadi, Takahiro Asami.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Páll-Gergely B, Hunyadi A, Asami T (2017) A new diplommatinid genus and two new species from the Philippines (Gastropoda, Caenogastropoda, Cyclophoroidea). ZooKeys 678: 1-10. https://doi.org/10.3897/zookeys.678.13059
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A new diplommatinid genus, Luzonocoptis Páll-Gergely & Hunyadi, gen. n. is erected for two new species, Luzonocoptis antenna Páll-Gergely & Hunyadi, sp. n. and L. angulata Páll-Gergely & Hunyadi, sp. n. Both species inhabit the northeastern part of Luzon Island, Philippines. The genus Luzonocoptis gen. n. is mostly characterized by a very slender shell with 14–18 whorls, a strongly expanded peristome, an interrupted, weak columellar lamella, the absence of any additional plicae or lamellae, and a rachidian tooth having five cusps.
Land snail, Luzon, rock habitat, systematics, taxonomy
Diplommatinidae (Caenogastropoda: Cyclophoroidea) are mostly characterized by small shells, a body whorl with a distinctive constriction, and teeth or plicae, which are situated inside the last whorl. This family is widely distributed in eastern and southern Asia, northern Australia, the Pacific islands, and some isolated distributions in South America and Madagascar (
The Diplommatinidae of the Philippines were mainly described in 12 papers by Otto von Möllendorff (
To date, the following species have been described from Cagayan Province, northern Luzon island: Palaina conspicua Möllendorff, 1893, P. conspicua versicolor Möllendorff, 1893, P. cristata Quadras & Möllendorff, 1893, Diplommatina cagayanica Möllendorff, 1893, D. latilabris Kobelt, 1886, Diplommatina (Sinica) concolor Quadras & Möllendorff, 1893, and D. (S.) filicostata Möllendorff, 1893) (see
Determination of number of shell whorls (precision to 0.25 whorl) follows
shell width diameter of the penultimate whorl perpendicular to coiling axis;
shell height length from apical tip to the edge of the basal section of the peristome parallel to coiling axis;
aperture height length from upper palatal to basal section of peristome parallel to coiling axis.
The mostly widely used terms were used in the descriptions, with the exception of the following: “post-constriction bay” refers to the widened area just anterior to operculum; “neck region” indicates the part of the body whorl on the opposite (“back”) side of the aperture.
D shell diameter
H shell height
HA collection András Hunyadi (Budapest, Hungary)
PGB Collection Barna Páll-Gergely (Mosonmagyaróvár, Hungary)
Shell sinistral; apex blunt, club-like; shell very slender with 14–18 whorls, rather regularly, finely ribbed; aperture round with a weak columellar lamella visible from standard apertural view; columellar lamella interrupted, its inner, short portion blunt thorn or tubercle-like, situated inside post-constriction bay; other inner plicae and lamellae absent; outer surface of operculum matt, smooth; inner surface with a very slightly elevated arcuate ridge; rachidian tooth with five cusps (central one blunt, larger than other four cusps), marginal teeth with four pointed cusps.
Luzonocoptis gen. n. differs from Palaina Semper, 1865 (type species: Diplommatina macgillivrayi Pfeiffer, 1854) by the unique shell shape, the strongly expanded peristome, and most importantly, the presence of a columellar tooth, which continues to a strongly developed lamella (see
The first part of the name derives from the name of the island (Luzon), where the included new species have been found. The second part (“-coptis”) refers to the similarity with Middle American urocoptid taxa in terms of shell size, shape, colour and habitat. Gender feminine.
Luzonocoptis antenna sp. n.
Luzonocoptis antenna sp. n. and L. angulata sp. n.
This genus is known so far from northeastern Luzon Island. The distance between the type localities of the two species is approximately 34 km in a straight line.
Philippines, Luzon, Cagayan Province, 20 km south-southeast from Baggao, Barangay San Miguel, environment of the Duba Cave, limestone rock wall on the bank of the Pared River, 50 m, 17°49.967'N, 121°56.042'E, leg. Hunyadi, A., 07.01.2014.,
Shells of Luzonocoptis gen. n. species. A–H Luzonocoptis antenna sp. n. (A–G holotype
Philippines, Luzon, Cagayan Province, 20 km south-southeast from Baggao, Barangay San Miguel, environment of the Duba Cave, limestone rock wall on the bank of the Pared River, 50 m, 17°49.967'N, 121°56.042'E.
A tall, yellowish, very slender diplommatinid with club-shaped apex, dense, low ribs on the last whorl, rounded lower whorls, strongly expanded and reflected peristome that is strongly oblique to the shell axis, and a weak interrupted columellar lamella.
(Figs
Shell height: 8.7–10.3 mm; shell width: 1.6–1.8 mm; aperture height: 2.2–2.7 mm (n = 6).
Operculum (Figs
Radula (Fig.
Shells, operculum and radula of Luzonocoptis gen. n. species. A–F Luzonocoptis antenna sp. n. A outer side of the operculum B inner surface of the operculum C SEM of the inner surface of the operculum D schematic drawing of the inner side, showing the slightly elevated ridge and the central nipple E radula (paratype no. 7.) F Neck region G Neck region of Luzonocoptis angulata sp. n. H protoconch of Luzonocoptis antenna sp. n. I protoconch of Luzonocoptis angulata sp. n. White arrow shows the constriction. All images B. Páll-Gergely.
The shell shape of this new species (wide aperture, very slender upper whorls, and a club-shaped apex) resembles a radio antenna. The specific epithet antenna to be used as a noun in apposition.
Living specimens were found on a limestone rock wall. This species is known from the type locality only, which is situated ca. 34 km in a straight line from the type locality of L. angulata sp. n.
Most sinistral diplommatinids from the Philippines belong to the genera Palaina and Diancta Martens, 1867, and have conical, ovoid, or cylindrical shells. However, most Diplommatina species from the Philippines are dextral, and the very few sinistral species have much lower spire, and triangular or ovoid shell shape (
Philippines, Luzon, Cagayan Province, 10 km southeast from Gattaran, Barangay Naddungan, environment of the Ar-Aro Cave, rock wall facing east, 90 m, 18°4.477'N, 121°44.128'E, leg. Hunyadi, 08.01.2014.
Philippines, Luzon, Cagayan Province, 10 km southeast from Gattaran, Barangay Naddungan, environment of the Ar-Aro Cave, rock wall facing east, 90 m, 18°4.477'N, 121°44.128'E.
A tall, yellowish, moderately slender diplommatinid with club-shaped apex, widely spaced, sharp ribs on the last whorl, angled lower whorls, strongly expanded peristome that is slightly oblique to the shell axis, and a weak interrupted columellar lamella.
(Figs
Shell height: 7.8–9.3 mm; shell width: 1.8–2.1 mm; aperture height: 2.2–2.6 mm (n = 5).
Operculum. Unknown.
The specific epithet angulata (Latin: angled) refers to the keeled lower whorls, which distinguishes this species from L. antenna sp. n.
Empty shells were found at the base of a limestone rock wall. This species is known from the type locality only, which is situated ca. 34 km in a straight line from the type locality of L. antenna sp. n.
See under Luzonocoptis antenna sp. n.
Although molecular phylogenetic studies involving numerous species were recently published (
The two Luzonocoptis gen. n. species are similar to species of the Palawan endemic genus Hungerfordia (type species: Hungerfordia pelewensis Beddome, 1889) in the rock-dwelling lifestyle, the sinistral coiling direction, the absence of parietal and palatal plicae or lamellae, and the low arcuate ridge on the inner surface of the operculum (
We are grateful to Rei Ueshima and Bernhard Hausdorf for important discussions and Junn Kitt Foon for reviewing the manuscript. This study was supported by Grants-in-Aid for Scientific Research (KAKENHI) from Japan Society for the Promotion of Science to T. Asami. Barna Páll-Gergely is an International Research Fellow of the Japan Society for the Promotion of Science. We are indebted to The Biodiversity Heritage Library for the multitude of rare literature made available to us (www.biodiversitylibrary.org).