Skip to main content

Landouria bella and Landouria monodon (Camaenidae Pilsbry 1895), new species from Thailand

NEWS - Researchers described the genus Landouria (Godwin-Austen, 1918) and identified two new species, Landouria bella and Landouria monodon. The team from Chaiyaphum Rajabhat University in Chaiyaphum and Mahasarakham University in Maha Sarakham noted that the two species were distinct from each other in the genus.

Landouria bella and Landouria monodon (Camaenidae Pilsbry 1895), new species from Thailand 1

Hirano et al. (2014) suggested that Landouria is a junior synonym of Aegista. In fact, a unique characteristic shared by all Landouria members in Thailand is the absence of a dart sac and a stimulatory organ, a combination of characters that are considered to define the family Camaenidae.

Benchawan Nahok and team showed that Landouria and Aegista are two distinct genera. Landouria has a small, compressed shell, a wide, open umbilicus, and the presence of flagella of various shapes. To date, more than 50 species have been recorded in the genus.

L. bella was collected from isolated limestone hills in Ratchaburi and Phetchaburi provinces, western Thailand. Small, concave-rounded shell without peripheral keel, presence of small and thin lamellae on the columellar side of the inner aperture, long, cylindrical, bent distally flagellum, short penis with rounded verge, short and thick free oviduct and vagina.



L. monodon was collected from sandstone hills in Kalasin Province, northeastern Thailand. The shell is concave-conical with blunt peripheral keel, thick prominent lamellae on the columellar side of the inner aperture, short, finger-shaped, bent distally flagellum, long penis with small and short verge.

Landouria bella and Landouria monodon (Camaenidae Pilsbry 1895), new species from Thailand 2

L. bella differs from all other species from Thailand by its concave and rounded shell. Other Thai Landouria species usually have slightly angular to prominent keels on the edges, as seen in L. monodon. The presence of small and thin columellar lamellae on the inner aperture of L. bella resembles that of L. monodon, but is more prominent.

Original research

Nahok B, Chanlabut U, Tumpeesuwan S, Tumpeesuwan C (2024) Two new species of Landouria Godwin-Austen, 1918 (Gastropoda, Camaenidae) from Thailand, with a key to Thai species. ZooKeys 1208: 347-362. DOI:10.3897/zookeys.1208.117056

Popular Posts

Bugang (Clerodendrum calamitosum)

Bugang ( Clerodendrum calamitosum ) is a species of plant in the Lamiaceae family. It is an erect shrub, growing up to 1 meter tall, with cylindrical, green stems and white hairs. The leaves are opposite. The leaf blade is oval, wavy, with a central main vein with numerous pinnate minor veins, and serrated margins. The leaves are up to 9 cm long and 7 cm wide. The petiole is up to 2 cm long. The flowers are star-shaped, white, up to 3 cm in diameter and up to 6 cm in total length. The fruit is round, dark green, turning black when ripe. TAXON Kingdom: Plantae Phylum: Tracheophyta Subphylum: Angiospermae Class: Magnoliopsida Order: Lamiales Family: Lamiaceae Subfamily: Ajugoideae Genus: Clerodendrum L. in Sp. Pl.: 637 (1753) Species: Clerodendrum calamitosum L. in Mant. Pl. 1: 90 (1767) HETEROTYPIC SYNONYMS Clerodendrum fastigiatum (W.Hunter ex Ridl.) H.J.Lam in Verben. Malay. Archip.: 317 (1919) Volkameria alternifolia Burm.f. in Fl. Indica: 137 (1768) Volkameria fastigiata W.Hunter...

Plumeria rubra and Plumeria obtusa, the differences

SPECIES HEAD TO HEAD - The genus frangipani trees ( Plumeria Tourn. ex L.) has only 18 officially recorded species and two very similar species, frangipani ( Plumeria rubra L.) and white frangipani ( Plumeria obtusa L.). Both have the same habitus, flowers and fruits and are difficult to distinguish. The leaves of both species have slightly different shapes. Therefore, the leaves are very important to distinguish the two species, especially the shape of the tip. P. rubra has simple, lanceolate leaves with acute tips. P. obtusa has simple, elliptic leaves with rounded tips. By Aryo Bandoro Founder of Dlium.com . You can follow him on X: @Abandoro . Read more: Plumeria rubra Plumeria obtusa

Durian (Durio zibethinus)

Durian ( Durio zibethinus ) is a species of tropical plant in Malvaceae, an annual tree, everlasting green but there are certain times to grow new leaves after the fruiting period is over, popularly called "king of fruit" and considered a controversial fruit where many people like, but some others are even fed up with the scent. D. zibethinus grows to 25-50 m, reddish brown bark and irregular peeling, leafy and stretched canopy. The leaves are oval shaped to lanceolate, 10-15x3-4.5 cm, sitting alternately, stemmed, taper or blunt base and taper-pointed sloping, bright green upper side, the lower side covered with silver or golden scales. Flowers and fruit Flowers appear directly on the trunk or old branches at the proximal, clustered in panicles containing 3-10 florets or flat-shaped florets. Rounded flower buds, 2 cm in diameter and long stem. Tubular petals, 3 cm long, additional petals split into 2-3 round lobes. Crown shaped spatula with a length of 2 times the ...