Paralaoma sarawakensis, Marzuki & Liew & Mohd-Azlan, 2021

Marzuki, Mohammad Effendi bin, Liew, Thor-Seng & Mohd-Azlan, Jayasilan, 2021, Land snails and slugs of Bau limestone hills, Sarawak (Malaysia, Borneo), with the descriptions of 13 new species, ZooKeys 1035, pp. 1-113 : 1

Paralaoma sarawakensis sp. nov. Figures 36B , 38

Material examined.

Holotype (SH 1.27 mm, SW 2.00 mm) (MZU.MOL.20.21), Malaysia, Sarawak, Kuching Division , Bukit Sokwang (Site 3), northern site of Gunung Doya, limestone hill along Skio road, 2.05 miles E Bau, 1°23'49.87"N, 110°10'32.14"E, coll. M. E. Marzuki, 22.IV.2017 . Paratypes: 1 ex. (ME0008944), same data as holotype ; 7 ex. (ME0008010), Gunung Sebayat , limestone hill near Bengoh resettlement scheme, along Jambusan-Semadang road, 10 miles SE Bau, 1°18'24.54"N, 110°15'21.80"E, coll. M. E. Marzuki, 13.IX.2016 ;> 10 ex. (ME0002234), Bukit Sekunyit , limestone quarry near Batu Kitang, Kuching-Bau road, 7.2 miles E Bau, 1°25'46.81"N, 110°15'47.20"E, coll. M. E. Marzuki, 10.III.2011 ; 4 ex. (ME0002269), Gunung Doya , limestone hill near Sungai Sebuyoh, 3.4 miles SE Bau, 1°22'57.24"N, 110°11'39.42"E, coll. M. E. Marzuki, 10.VII.2011 ; 8 ex. (ME0002230), Gunung Batu , limestone outcrop along Skio road, Jambusan, 2.4 miles E Bau, 1°23'50.65"N, 110°11'19.99"E, coll. M. E. Marzuki, 23.VI.2010 ; 5 ex. (ME0002235), the same locality, coll. M. E. Marzuki, 11.III.2011 ; 9 ex. (ME0002257), the same locality, coll. M. E. Marzuki, 10.VII.2011 ;> 10 ex. (ME0002229), Fairy Caves , south part of Gunung Kapor, 4 miles SW Bau, Kuching Division, 1°22'53.97"N, 110°7'2.29"E, coll. M. E. Marzuki, 11.III.2011 ; 2 ex. (ME0009211), Fairy Caves (Site 2), south part of Gunung Kapor, 4 miles SW Bau, 1°22'56.09"N, 110°6'58.82"E, coll. M. E. Marzuki, 8.IV.2017 ; 1 ex. (ME0009261), Buddha Caves (Site 3), north part of Gunung Kapor, 3 miles SW Bau, 1°23'26.51"N, 110°7'10.02"E, coll. M. E. Marzuki, 9.IV.2017 ; 1 ex. (ME0002233), South Flank of Bukit Akud , near Kampung Beratok, Serian-Kuching road, 14 miles NW Serian, 1°18'23.26"N, 110°24'15.07"E, coll. M. E. Marzuki, 21.VI.2010 ; 2 ex. (ME0006975), Gua Raya , along Kampung Skuduk-Chupak, 8.8 miles SE Siburan, 1°14'23.29"N, 110°25'49.05"E, coll. M. E. Marzuki, 1.I.2016 ; 2 ex. (MZU.MOL.20.22),> 10 ex. (ME0007998), North side of Gua Raya, along Kampung Skuduk-Chupak, 8.3 miles SE Siburan, 1°14'35.10"N, 110°25'51.08"E, coll. M. E. Marzuki, 17.IX.2016 ;> 10 ex. (ME0000430), Limestone escarpment near Kampung Benuk, 8.2 miles SW Kota Padawan, 1°18'41.43"N, 110°17'32.03"E, coll. M. E. Marzuki, 27.X.2008 ;> 10 ex. (ME0002258), the same locality, coll. M. E. Marzuki, 22.VI.2010 ;> 10 ex. (ME0002256), the same locality, coll. M. E. Marzuki, 9.III.2011 ; 7 ex. (ME0007966), the same locality, coll. M. E. Marzuki, 13.IX.2016 ; 3 ex. (ME0009461), the same locality, coll. M. E. Marzuki, 22.IX.2017 ; 1 ex. (ME0002231), Serian Division, Gua Sireh, Bukit Nambi, limestone outcrops near Kampung Taee, 7 miles W Serian, 1°10'36.18"N, 110°27'53.81"E, coll. M. E. Marzuki, 21.VI.2010 ; 6 ex. (ME0002232), Gunung Suka , Limestone outcrop 7.5 km from Kampung Picsing, Tebakang-Tebedu road, 8.45 miles SW Serian, 1°8'5.08"N, 110°26'53.30"E, coll. M. E. Marzuki, 20.VI.2010 ;> 10 ex. (ME0009386), Gunung Silabur , limestone hill near Kampung Lobang Batu, 15 miles S Serian, 0°57'22.63"N, 110°30'9.36"E, coll. M. E. Marzuki, 22.IX.2017 ; 2 ex. (ME0000644), Miri Division , limestone outcrop near logging road, Baram Valley, 3.5 miles SW Long Bemang, 11 miles NE Long Lama, 3°49'50.36"N, 114°33'15.09"E, coll. M. E. Marzuki, 4.XI.2012 ; 1 ex. (ME0002751), Small limestone outcrop near Bemang-Bedian Junction, 5.4 miles E Long Lama, 3°46'15.701"N, 114°28'52.693"E, coll. M. E. Marzuki, 16.VIII.2013 .

Differential diagnosis.

It differs from ' Charopa ' Charopa lafargei Vermeulen & Marzuki, 2014 of West Malaysia, by having a depressed-conical shell and a protoconch with fine, moderately spaced, spiral striations consisting of rows of minute striae which are arranged in a dashed-line pattern towards the teleoconch.

Description.

Shell very small, dextral, rather solid, translucent, white; spire depressed. Surface with a silky lustre. Whorls slightly convex. Number of whorls < 4¼. Protoconch with a fine, moderately spaced, spiral striation consisting of rows of minute, striae are crossed by well-spaced radial grooves arranged in a dashed-line pattern towards the teleoconch. Teleoconch: spiral sculpture present with very distinct, moderately spaced, continuous striae arranged as dashed lines. Radial sculpture of teleoconch consisting of well-spaced, coarse, orthocline, slightly sinuous, high narrow ribs which reach down to the spiral ridge and are fused to it; interstices with inconspicuous radial grooves. Periphery rounded, slightly angular; suture deep. Aperture lunulate. Peristome simple; somewhat reflected on columellar side, not thickened nor reflected on basal or palatal sides. Umbilicus open, narrow; umbilical region moderately concave. Dimensions: Shell height <1.27 mm; shell width <2.00 mm; diameters of the first three whorls 0.17 mm, 0.20 mm, and 0.23 mm, respectively; aperture height <0.67 mm; aperture width <1.00 mm.

Geographic distribution and habitat.

It has a wide distribution in Sarawak. Living snails were observed foraging among leaf litter and plant debris near the cliffs in a lowland limestone forest and in a lowland non-limestone forest.

Etymology.

The specific epithet Paralaoma sarawakensis is derived from the name of Malaysian State of Sarawak.

Figures

Figure 36. A Paralaoma angusta Vermeulen, Liew & Schilthuizen, 2015 ME 9641 Gunung Kapor B Paralaoma sarawakensis, sp. nov., ME 2269 Paratype Gunung Doya C Charopa sp. " Charopa argos " ME 8593 Gunung Doya.

Figure 38. Paralaoma sarawakensis, sp. nov. A-F MZU. MOL. 20.21 Holotype A apertural view B apical view C basal view D enlargement of the apical side showing the apex E enlargement of the teleoconch showing the shell sculpture F enlargement of the basal side of the shell.