Craspedotropis gretathunbergae, Schilthuizen & Lim & van Peursen & Alfano & Jenging & Cicuzza & Escoubas & Escoubas & Grafe & Ja & Koomen & Krotoski & Lavezzari & Lim & Maarschall & Slik & Steele & Ting & van Zeeland & Njunjić, 2020

Schilthuizen, Menno, Lim, Jonathan P, van Peursen, Anthonie D. P., Alfano, Massimiliano, Jenging, Awang Bikas, Cicuzza, Daniele, Escoubas, Alexandre, Escoubas, Pierre, Grafe, Ulmar, Ja, Jamil, Koomen, Peter, Krotoski, Aleks, Lavezzari, Denise, Lim, Laura, Maarschall, Rudie, Slik, Ferry, Steele, Derek, Ting, Dennis Teck Wah, van Zeeland, Ine & Njunjic, Iva, 2020, Craspedotropis gretathunbergae, a new species of Cyclophoridae (Gastropoda: Caenogastropoda), discovered and described on a field course to Kuala Belalong rainforest, Brunei, Biodiversity Data Journal 8, pp. 47484-47484 : 47484

Craspedotropis gretathunbergae sp. n.

Materials

Type status: Holotype. Occurrence: catalogNumber: 7.00141 ; recordedBy: Jonathan Lim and other Taxon Expeditions participants; individualCount: 1; sex: unknown; lifeStage: adult; preparations: total individual, dry, with dried-up tissue inside the shell; disposition: in collection; Taxon: scientificName: Craspedotropisgretathunbergae Schilthuizen et al.; kingdom: Animalia; phylum: Mollusca; class: Gastropoda; order: Caenogastropoda; family: Cyclophoridae; genus: Craspedotropis; specificEpithet: gretathunbergae; taxonRank: species; scientificNameAuthorship: Schilthuizen et al.; nomenclaturalCode: ICZN; Location: continent: Asia; island: Borneo; country: Brunei; stateProvince: Temburong; verbatimLocality: Ulu Temburong, 50 m downstream from Kuala Belalong Field Studies Centre, on green leaves near river bank; verbatimElevation: 50 m; verbatimCoordinateSystem: decimal degrees; decimalLatitude: 4.5478; decimalLongitude: 115.1578; Event: samplingProtocol: manual collecting at night; eventDate: 2019-09-28; eventTime: 20:00/22:00; habitat: primary dipterocarp forest; Record Level: type: PhyscalObject; institutionID: UBD; institutionCode: IBER-UBD; collectionCode: Zoology; basisOfRecord: PreservedSpecimen Type status: Paratype. Occurrence: catalogNumber: 7.00142 ; recordedBy: Jonathan Lim and other Taxon Expeditions participants; individualCount: 1; sex: unknown; lifeStage: adult; preparations: total individual, dry, with dried-up tissue inside the shell; disposition: in collection; Taxon: scientificName: Craspedotropisgretathunbergae Schilthuizen et al.; kingdom: Animalia; phylum: Mollusca; class: Gastropoda; order: Caenogastropoda; family: Cyclophoridae; genus: Craspedotropis; specificEpithet: gretathunbergae; taxonRank: species; scientificNameAuthorship: Schilthuizen et al.; nomenclaturalCode: ICZN; Location: continent: Asia; island: Borneo; country: Brunei; stateProvince: Temburong; verbatimLocality: Ulu Temburong, 50 m downstream from Kuala Belalong Field Studies Centre, on green leaves near river bank; verbatimElevation: 50 m; verbatimCoordinateSystem: decimal degrees; decimalLatitude: 4.5478; decimalLongitude: 115.1578; Event: samplingProtocol: manual collecting at night; eventDate: 2019-09-28; eventTime: 20:00/22:00; habitat: primary dipterocarp forest; Record Level: type: PhyscalObject; institutionID: UBD; institutionCode: IBER-UBD; collectionCode: Zoology; basisOfRecord: PreservedSpecimen Type status: Paratype. Occurrence: catalogNumber: 7.00143 ; recordedBy: Jonathan Lim and other Taxon Expeditions participants; individualCount: 1; sex: unknown; lifeStage: adult; preparations: 2 total individuals, in 70% ethanol; disposition: in collection; Taxon: scientificName: Craspedotropisgretathunbergae Schilthuizen et al.; kingdom: Animalia; phylum: Mollusca; class: Gastropoda; order: Caenogastropoda; family: Cyclophoridae; genus: Craspedotropis; specificEpithet: gretathunbergae; taxonRank: species; scientificNameAuthorship: Schilthuizen et al.; nomenclaturalCode: ICZN; Location: continent: Asia; island: Borneo; country: Brunei; stateProvince: Temburong; verbatimLocality: Ulu Temburong, 50 m downstream from Kuala Belalong Field Studies Centre, on green leaves near river bank; verbatimElevation: 50 m; verbatimCoordinateSystem: decimal degrees; decimalLatitude: 4.5478; decimalLongitude: 115.1578; Event: samplingProtocol: manual collecting at night; eventDate: 2019-09-28; eventTime: 20:00/22:00; habitat: primary dipterocarp forest; Record Level: type: PhyscalObject; institutionID: UBD; institutionCode: IBER-UBD; collectionCode: Zoology; basisOfRecord: PreservedSpecimen Type status: Paratype. Occurrence: catalogNumber: 7.00144 ; recordedBy: Jonathan Lim and other Taxon Expeditions participants; individualCount: 1; sex: unknown; lifeStage: adult; preparations: 3 total individuals, in 100% ethanol; disposition: in collection; Taxon: scientificName: Craspedotropisgretathunbergae Schilthuizen et al.; kingdom: Animalia; phylum: Mollusca; class: Gastropoda; order: Caenogastropoda; family: Cyclophoridae; genus: Craspedotropis; specificEpithet: gretathunbergae; taxonRank: species; scientificNameAuthorship: Schilthuizen et al.; nomenclaturalCode: ICZN; Location: continent: Asia; island: Borneo; country: Brunei; stateProvince: Temburong; verbatimLocality: Ulu Temburong, 50 m downstream from Kuala Belalong Field Studies Centre, on green leaves near river bank; verbatimElevation: 50 m; verbatimCoordinateSystem: decimal degrees; decimalLatitude: 4.5478; decimalLongitude: 115.1578; Event: samplingProtocol: manual collecting at night; eventDate: 2019-09-29; eventTime: 20:00/22:00; habitat: primary dipterocarp forest; Record Level: type: PhyscalObject; institutionID: UBD; institutionCode: IBER-UBD; collectionCode: Zoology; basisOfRecord: PreservedSpecimen

Description

Spire (Fig. 1 ): Protoconch without distinct sculpture; juncture with the teleoconch not visible. Spire high conical, consisting of 5.25 to 5.75 convex whorls. Suture depressed. Radial sculpture: growth lines and densely placed riblets (30-70 per mm on the body whorl). Spiral sculpture: 4 high, prominent, here and there somewhat crenellated radial ribs, which start after 1.5 to 2.0 whorls. The first spiral rib (from the top) is located between the periphery and the suture with the previous whorl. The second sits at the periphery. The third is located near the suture with the next whorl and is visible on the body whorl in some, but not all, individuals. The fourth is located on the basal side and only visible on the edge of the umbilicus. Between the ribs are fine spiral lines. Umbilicus wide, without additional spiral ribs. Height 2.7 - 2.9 mm, width 1.7 - 1.8 mm. Periostracum greenish-yellow, deep brown when thickened (e.g. near the aperture).

Aperture (Fig. 3 ) Aperture slightly wider than high, peristome slightly thickened, with angularities coinciding with the four spiral ribs, but without sinuosities; basal side horizontal. The peristome carries ca. 10 tightly packed accretions, coloured dark brown because of the thickened periostracum. Height 0.86 - 0.90 mm, width 0.92 - 0.97 mm.

Operculum (Figs 1 , 3 ): Operculum thin, corneous, whorl margins not raised but flattened into a smooth concave dish, of which the outer part is greenish-brown (presumably because of a thickly applied periostracum), the central part nearly clear. No calcareous matter visible.

Body (Fig. 2 ): Body pale, tentacles dark grey, buccal mass visible as a pink-orange globule. (See also Suppl. material 1)

Genitalia: Not studied.

Diagnosis

Amongst the Bornean cyclophorids, Craspedotropis gretathunbergae n. sp. is most similar to C. borneensis ( Godwin Austen 1889), which, however, is somewhat less slender, has 7 - 9 spiral ribs and more broadly reflected apertural lip. In addition, the operculum of C. borneensis has raised whorl margins, which is not the case in C. gretathunbergae n. sp. Other Asian species, with which the new species may be confused, are: (i) Cyathopoma conoideum Sykes 1898, which has a more slender shell and the spiral ribs arranged in a different pattern, with the second rib located just above the suture; (ii) C. sivagherrianum Beddome 1875, which is smaller, has 7 spiral ribs and a nearly closed umbilicus; (iii) C. beddomeanum Nevill 1881, which has more (7 - 8) and more prominent, spiral ribs, more globular whorls and a rounder aperture; (iv) C. procerum Blanford 1868, which is stockier, has 9 - 12 spiral ribs and a peristome that is strongly thickened by folds.

Etymology

We name this species in honour of the young climate activist Greta Thunberg, because caenogastropod microsnails from tropical rainforests, like this new species, are very sensitive to the droughts and temperature extremes that are likely to be more frequent as climate change continues. Via mutual contacts, we have approached Ms. Thunberg and learned that she would be 'delighted' to have this species named after her.

Following Recommendation 51C of the Code ( ICZN 1999), if it is desired that authorship of the name be included as part of the name, instead of listing all authors, the species can be referred to as Craspedotropis gretathunbergae Schilthuizen et al., 2019, provided that all authors of the name are cited in full elsewhere in the same work, either in the text or in a bibliographic reference.

Distribution

Borneo: Brunei Darussalam: Temburong District: Ulu Temburong lowland rainforest.

Ecology

In tropical mixed dipterocarp lowland rainforest. All individuals were found alive at the foot of a steep hill-slope, next to a river bank, foraging at night on the upper surfaces of green leaves of understorey plants, up to 1 m above ground level.

Taxon discussion

The generic classification of minute cyclophorids in Southeast Asia is somewhat confused. The genera Craspedotropis Blanford 1864, Cyathopoma Blanford 1861 Blanford and Blanford 1861, Jerdonia Blanford 1861 ( Blanford and Blanford 1861; sometimes considered a subgenus of Cyathopoma ) and Ditropopsis Smith 1897 appear poorly defined and may be partly overlapping or synonymous ( Vermeulen et al. 2015, Vermeulen 1999). In its general shell form (a tall conical shell with spiral ribs), the present species is similar to several species of Cyathopoma (e.g. the South Asian C. conoideum Sykes 1898, C. sivagherrianum Beddome 1875, C. beddomeanum Nevill 1881 and C. procerum Blanford 1868) and Craspedotropis , especially C. borneensis ( Godwin Austen 1889), known from Sarawak. Given the geographical proximity of the latter, we have tentatively placed the new species in the same genus, Craspedotropis .

Figures

Figure 1. Craspedotropis gretathunbergae n. sp., holotype (IBER-UBD 7.00141), shell in apertural view. Photo by Pierre Escoubas.

Figure 2. Active individual of Craspedotropis gretathunbergae n. sp. (paratype, IBER-UBD 7.00142), taken from a video file (Suppl. material 1). Image by Pierre Escoubas.

Figure 3. Craspedotropis gretathunbergae n. sp. (paratype, IBER-UBD 7.00143) a, shell with operculum in apertural view. b, detail of the body whorl in lateral view. c, detail of the shell in umbilical view.