Beroe sp. B

Verhaegen, Gerlien, Cimoli, Emiliano & Lindsay, Dhugal, 2021, Life beneath the ice: jellyfish and ctenophores from the Ross Sea, Antarctica, with an image-based training set for machine learning, Biodiversity Data Journal 9, pp. 69374-69374 : 69374

Beroe sp. B

Materials

Type status: Other material. Occurrence : individualID: MCMEC2019_ Beroe _sp_B_a; associatedMedia: "http://morphobank.org/permalink/?P3993", "https://youtu.be/VC-peoIaI0I"; Taxon : kingdom: Animalia ; phylum: Ctenophora ; class: Nuda ; order: Beroida ; genus: Beroe ; Location: continent: Antarctica; waterBody: McMurdo Sound; maximumDepthInMeters: 1; decimalLatitude: -77.637; decimalLongitude: 166.401; Identification: identifiedBy: Dhugal Lindsay; Event: samplingProtocol: Sony Alpha 7 III camera equipped with a FE 90mm F2.8 Macro G OSS lens; eventDate: 2019-11-15; Record Level: type: StillImage, Video; language: en; rightsHolder: Emiliano Cimoli

Distribution

First reported observation.

Notes

Description of and comments on observed material: N = 1 in 2019 (Fig. 12 ). Body length ca. 35 mm, body shape oval (body length ca. 1.5 times body width); colour transparent to milky white; length of comb rows 1/4 of the body length; ca. 22 comb plates per comb row; space between five comb plates ca. equal to width of comb plate and length of comb plates four times the width of a comb plate; length of meridional canals full body length; length stomodeum ca. equal to body length; no diverticula; small yellow round deposits located within the walls of the meridional canals (could be gonads, sperm, eggs or oil droplets). None of the currently described adult Beroe species found in the Southern Ocean matched with the description of our specimen (Table 1 ); however, the lack of colour and the shortness of the comb rows vs. body length could indicate our specimen was a juvenile. Indeed, despite the colour of juvenile individuals being rarely included in the description or re-description of Beroe species, when reported, juveniles are either colourless (e.g. B. abyssicola Mortensen, 1927), transparent (e.g. B. ovata sensu Chun, 1880 and B. pandorina Moser, 1903) or of lighter colour (e.g. B. abyssicola in Arai 1988) compared to intraspecific adults. Shorter comb rows vs. body length in larvae or young specimens compared to adults have been reported for B. campana ( Komai 1918), B. forskalii ( Moser 1903), B. gracilis ( Künne 1939), B. mitrata ( Moser 1907), B. ovata sensu Mayer, 1912 ( Mayer 1912) and B. ramosa ( Komai 1921). However, even when shorter, the comb length in juveniles of the Beroe species listed above usually extended up to half the body length. Therefore, the comb row length of our observed species is unusually short, regardless of its life stage and, therefore, likely it is a Beroe species not yet reported to occur in the Southern Ocean.

Figures

Figure 12. Beroe sp. B specimen MCMEC 2019 _ Beroe _ sp _ B _ a observed on 15 / 11 / 2019: lateral views (A-B) and oral view (C). Photos courtesy: E. Cimoli.