The genus Lilloiconcha in Colombia (Gastropoda: Charopidae)

The name Lilloiconcha Weyrauch, 1965 is used tentatively for South American charopids with a reduced penis, a barely differentiated epiphallus and multicuspid marginal radular teeth. Trochogyra Weyrauch, 1965 is considered to be a synonym of Lilloiconcha. In addition to the widespread Lilloiconcha gordurasensis (Thiele, 1927), Lilloiconcha costulata new species and Lilloiconcha laevigata new species are described from the Cordillera Oriental in Colombia. The distribution of Lilloiconcha gordurasensis in South America is summarized.


Introduction
established the names Lilloiconcha Weyrauch, 1965 for a single species which usually has basal and parietal denticles in juvenile stages, Austrodiscus superbus tucumanus Hylton Trochogyra Weyrauch, 1965 (Gastropoda: Charopidae) as a subgenus of Zilchogyra Weyrauch, 1965 for a single conical species with a narrow umbilicus, Endodonta superba Thiele, 1927. Fonseca andThomé (1993) separated Trochogyra as a genus from Zilchogyra. They mentioned that there is a microsculpture on the apparently smooth protoconch of Trochogyra, whereas the protoconch of Zilchogyra is completely smooth. They transferred several species included by Weyrauch (1965) in Zilchogyra (Zilchogyra) to Trochogyra. Moreover, they established a new subgenus, Glabrogyra Fonseca and Thomé, 1993, for two species from Chile. Schileyko (2001) separated Glabrogyra Fonseca and Thomé, 1993 as a distinct genus. The monotypic Lilloiconcha Weyrauch, 1965 from northern Argentina was retained by Fonseca and Thomé (1993) and Schileyko (2001). Species classified with Trochogyra by Fonseca and Thomé (1993) were known from Peru, Brazil, Paraguay, Argentina, and Chile. During a land snail survey by the author and staff of the Facultad de Ciencias of the Universidad Militar Nueva Granada in Colombia, three charopid species belonging to this group were found in the Cordillera Oriental in the Distrito Especial and the Departamentos Cundinamarca and Boyacá. In the following review the anatomy of one of these species is described in detail, the application of the existing genus group names is discussed, and the Colombian species are described.

Material and methods
Specimens which were collected alive in the field were killed by drowning in water for a few hours and conserved in 70% ethanol. Most of the material was extracted from dried litter samples.
Radulae were prepared by dissolving the dissected buccal mass or complete dried specimens in 5% potassium hydroxide for several hours. Then they were cleaned in an ultrasonic cleaner for 10 s and washed with distilled water. The cleaned radula was mounted on a small piece of coverslip in water and allowed to dry directly on to the glass. The coverslip was fixed to a SEM stub using double-sided tape and sputtered with gold in a sputter coater (GEA004S). The radulae were examined in a Leo 1525 scanning electron microscope.
The counting of the shell whorls (accuracy 0.25) follows Kerney and Cameron (1979, p 13). Shells were photographed without coating in a variable pressure scanning electron microscope (Leo 1455VP).
The material on which this study is based is kept in the following collections: Museo de La Plata, La Plata (MLP); Instituto de Ciencias Naturales of the Universidad Nacional de Colombia, Santafé de Bogotá (UNAL); Zoologisches Museum der Humboldt-Universität, Berlin (ZMB); Zoologisches Museum der Universität Hamburg (ZMH).

Diagnosis
Lilloiconcha costulata differs from other Lilloiconcha species in the depressed conical-globular shell with moderately coarse ribs. The shell is more depressed than in the almost conical Lilloiconcha pleurophora (Moricand, 1846), but less depressed than in Lilloiconcha gordurasensis (Thiele, 1927) and the ribs are weaker than in both these species.
Shell (Figures 1, 4 ribs (ca 6-9 per 1 mm of the body whorl) and a reticulate pattern consisting of fine growthstriae and dense microscopical spiral threads between the ribs; brownish corneous with reddish brown transverse stripes; body whorl rounded; aperture almost circular; upper insertion of the peristome not descending towards the aperture; suture impressed; peristome sharp, neither expanded nor thickened; umbilicus wide, about 24-30% of the shell diameter.
Mantle. Mantle with large, fused black spots and small white dots. Mantle collar ( Figure 10) broad, with a narrow, indistinctly delimited left mantle lobe and a broad, almost rectangular right mantle lobe. Pneumostome separated by a small, elongate-conical subpneumostomal mantle lobe.
Pallial complex ( Figure 11). Pallial complex about three times as long as the broad kidney, which extends to the hindgut. The kidney is slightly longer than the pericardium. It opens into the reflexed primary ureter near its anterior end. The primary ureter is continued by a tube-like secondary ureter along the hindgut, which ends with the ureteric pore opening next to the anus inside the pneumostome. Lung long and narrow, without coarse venation.
Genitalia ( Figure 12). The male copulatory organs are strongly reduced. The penis forms a lateral swelling at the large atrium and contains a conical papilla. The penis retractor inserts near the proximal end of the penis and at the diaphragm. It crosses the right ommatophoral retractor. The vas deferens is very broad and enters the penis terminally. No differentiated epiphallus could be discerned. The vagina is very short. The peduncle of the bursa copulatrix is long. The small bursa of the bursa copulatrix reaches the digestive gland. The free oviduct is short. The right ommatophoral retractor does not run between penis and vagina.
Radula (Figures 13-15). The tricuspid central teeth are narrower and shorter than the adjacent lateral teeth. The slender central cusps of the central teeth are about three times as long as the side cusps. The central cusp of the tricuspid lateral teeth is shifted backwards. It is connected with the large and strongly curved side cusps by a low bridge which begins between the bases of the side cusps with an apparent extra denticle. The side cusps of the lateral teeth are raised above the elevation plane of the mesocone. Towards the periphery the endocone of the lateral teeth increases and approximates the mesocone. At the transition to the marginal teeth extra denticles develop next to the ectocone so that the marginal teeth are multicuspid.

Etymology
The specific epithet refers to moderately coarse ribs which characterize the species (Latin costulatus).

Diagnosis
Lilloiconcha laevigata differs from Lilloiconcha costulata in the lack of ribs and the on average larger shell with more whorls. It also differs from other Lilloiconcha species in the lack of ribs.

Anatomy (Figures 16-20)
Only the radula of one paratype from La Calera, 0.5 km towards Bogotá (ZMH 4068) could be examined. The tricuspid central teeth are narrower and shorter than the adjacent lateral teeth. The slender central cusps of the central teeth are more than twice as long as the side cusps. The central cusp of the tricuspid lateral teeth is shifted backwards. It is connected with the large and strongly curved side cusps with a low bridge which begins between the bases of the side cusps with an apparent extra denticle, sometimes with two tips. Towards the periphery the endocone of the lateral teeth increases and approximates the mesocone. At the transition to the marginal teeth extra denticles develop next to the ectocone so that the marginal teeth are multicuspid.

Etymology
The specific epithet refers to the comparatively smooth (Latin laevigatus) shell which characterizes the species.

Diagnosis
Lilloiconcha gordurasensis differs from the other Columbian Lilloiconcha species in the on average smaller, more depressed shell with coarser and denser ribs and a wider umbilicus.

Shell (Figures 3, 8, 9)
Depressed conical-globular; with 3.75-4.25 convex whorls; protoconch with distinct microscopical spiral threads; teleoconch with coarse and regular ribs (10-13 per 1 mm of the body whorl) and a reticulate pattern consisting of fine growth-striae and dense microscopical spiral threads between the ribs; brownish corneous with reddish brown transverse stripes; body whorl rounded; aperture almost circular; upper insertion of the peristome not descending towards the aperture; suture impressed; peristome sharp, neither expanded nor thickened; umbilicus very wide, taking about 34-38% of the shell diameter.
Distribution (Figures 21, 22) Lilloiconcha gordurasensis was known so far from eastern Brazil, Paraguay and north-western Argentina (Thiele 1927;Jaeckel 1952;Miquel et al. 2004). In Colombia it was found in Andean forests at 1700-1840 m altitude in the Departamentos Cundinamarca and Boyacá. The occurrences in Colombia represent the highest localities from which Lilloiconcha gordurasensis has been recorded. The species has also been discovered in the Departamentos San Martín and Huánuco in Peru by Z. Guevara.

Material
Colombia, Cundinamarca: La Mesa, 12 km towards Bogotá, Los Alpes near El Rosario, W slope with forest, 1700 m altitude, 04u409140N, 74u239430W (UNAL; ZMH 4317). Colombia, Boyacá: Barbosa, 5 km towards Arcabuco, forest near quarry El Cairo in Vereda Figure 22. Distribution of Lilloiconcha gordurasensis (Thiele) in South America (2u-grid). examine juvenile shells of Zilchogyra (Trochogyra) superba. No denticles have been found in juvenile shells of Lilloiconcha costulata, Lilloiconcha laevigata, Lilloiconcha gordurasensis, and Lilloiconcha pleurophora. The variability of the development of the denticles in Lilloiconcha tucumana shows that their presence is not even species specific and can hardly be used to substantiate the establishment of a distinct genus. Weyrauch (1965) states that Lilloiconcha tucumana differs from Zilchogyra (Trochogyra) superba also in the completely smooth protoconch. Thus, Lilloiconcha tucumana should be related to Zilchogyra rather than to Trochogyra according to the diagnosis given by Fonseca and Thomé (1993). However, the spiral sculpture of the protoconch can sometimes be recognized only by means of a scanning electron microscope, and the protoconch of well-preserved specimens of Lilloiconcha tucumana has not yet been examined with a scanning electron microscope. It cannot be excluded that there is also a spiral protoconch sculpture in that species. Thus, the known conchological differences between Endodonta superba and Austrodiscus superbus tucumanus are not sufficient to classify these very similar and geographically neighbouring species in different genera at the present state of knowledge. Of course their classification has to be reconsidered when their anatomy becomes known. According to Article 24.1 of the International Code of Zoological Nomenclature (International Commission on Zoological Nomenclature 1999), Lilloiconcha Weyrauch, 1965 has priority over Zilchogyra (Trochogyra) Weyrauch, 1965 because it was established for a genus.
There is another conchologically similar species of which the anatomy is known, P. leptotera Rochebrune and Mabille, 1882 from Patagonia (see Hylton Scott 1970). This species differs from Lilloiconcha pleurophora and Lilloiconcha costulata in the well-developed penis, a differentiated epiphallus, the lack of a vagina, and tricuspid radular marginals. It differs from Zilchogyra costellata in the shorter penis (perhaps with two sections) and shorter epiphallus, the insertion of the penis retractor at the distal section of the epiphallus and the lack of a vagina. Nevertheless, Hylton Scott (1970) and Schileyko (2001) included it in Zilchogyra, whereas Fonseca and Thomé (1993) classified it with Trochogyra. Probably a new genus has to be established for that species. This makes clear that a classification of the species belonging to the discussed groups based on conchological characters only is hardly possible. As long as the anatomy of the type species of the established genus group names like Lilloiconcha Weyrauch, 1965, Trochogyra Weyrauch, 1965, and Glabrogyra Fonseca and Thomé, 1993 is not known, the classification and nomenclature of the groups involved will remain tentative.
The suprageneric classification of the Punctoidea is also in confusion. Vaz (1991) included Lilloiconcha pleurophora (which he classified as Austrodiscus (Zilchogyra)) in the Helicodiscinae (Endodontidae). Fonseca and Thomé (1993) classified Trochogyra with the Rotadiscinae (Charopidae), but Lilloiconcha and Zilchogyra with the Helicodiscidae. Schileyko (2001) included all these genera in his Trachycystinae (Endodontidae), which are characterized by ''spermatophores found in penis'' according to his diagnosis. However, a spermatophore has not so far been found in any of the mentioned South American genera. Also, the other classifications lack a thorough substantiation.
A phylogenetic analysis of the Punctoidea is still not available. Therefore, the classification of the Punctoidea proposed by Solem (1976Solem ( , 1983) is used here. According to that classification, Lilloiconcha can be classified with the Charopidae, because of the presence of a secondary ureter, the fusion of the prostate and the oviduct, the tricuspid radular lateral teeth (the side cusps of which are raised above the elevation plane of the mesocone), the dominant spiral threads on the protoconch and the lack of apertural denticles. According to Solem's (1983) diagnosis, Lilloiconcha does not belong to the Rotadiscinae where it has been included by Fonseca and Thomé (1993), but to the Charopinae, because the spiral sculpture on the protoconch is not composed of short segments, but of continuous threads. The Charopinae sensu Solem are probably only a non-monophyletic conglomerate of charopids which were not assigned to one of the other, more restrictively defined subfamilies (Solem 1983). Both Lilloiconcha and Zilchogyra differ from most other sufficiently known Charopidae in the lack of a rectal lobe of the kidney. However, this might be only a symplesiomorphy.