Table 2 in Glaciambulata neumayeri gen. et sp. nov., a new Antarctic trachymedusa (Cnidaria: Hydrozoa), with a revision of the family Ptychogastriidae

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Horia R. Galea;Cornelia Roder;Christoph Walcher;Marco Warmuth;Eberhard Kohlberg;Philipp F. Fischer

Description

Table 2 (continued on next page). Morphological comparison between the nominal species Pectis antarctica Haeckel, 1879 and Voragonema laciniata Bouillon et al., 2001.P. antarctica Haeckel, 1879V. laciniata Bouillon et al., 2001ReferencesHaeckel (1881b)Bouillon et al. (2001), Lindsay & Pagès (2010)Distribution60°52′ S, 80°20′ E (500–600 km off eastern Antarctica)Weddell Sea, AntarcticaUmbrellaDome-shaped to “almost hemispherical; about 1½ times as broad as high”, ca. 24 mm high and 36 mm wide “Exumbrella Fnely radially ribbed” “The gelatinous substance of the umbrella […] is nearly of equal thickness in the upper aboral half of the umbrella”; “much thinner in the lower oral half, hardly one-fourth or one- Ffth as thick as in the upper half” “The ectodermal epithelium of […] the subumbrella consists of cells of dark brown pigment” “The underlying annular system of the subumbrella forms numerous compact circular folds”Dome-shaped to hemispherical, almost as high (30 mm) as wide (35 mm) Exumbrella transparent, with numerous Fne, meridional ridges Mesoglea 4 mm thick in the apex, thinning out towards umbrella margin Subumbrella dark red-brownish colored Musculature of subumbrella consisting of both circular and crossed oblique-radial musclesGastric peduncleThe mesoglea “is very much thickened in the centre of the apex, and projects into the fundus of the gastral cavity in the form of a short, conical, gelatinous appendage”Large, circular from above and slightly octagonal from the subumbrellar cavityCanal system“The eight radial canals […] which run from the basis of the stomach to the umbrella margin, and there open into the circular canal, as well as the circular canal itself […], and the blind centripetal canals proceeding from it, are not cylindrical tubes, but Fattened band- like vessels which are sharply distinguished by then milk-white colour from the dark violet subumbrella”; “11-13 blind radial canals (3 larger and 8-10 smaller) between each two radial canals […] have the form of a pointed equilateral triangle”; “number and8, white-cream colored, straight; peduncular part 5 mm long and 1.5 mm wide; proximal half of the subumbrellar part narrow, 0.5 mm wide, distal half broader, 1.3 mm wide. Ring canal wide, giving rise to 11–13 conically-shaped, irregular in length and width, centripetal canals in each octantarrangement […] not perfectly regular”Manubrium“The central oesophagus hangs down from the fundus of the umbrella cavity till past the middle of it in the shape of a quadrangular tube […]” “Oral cavity with with 8 pairs of hemispherical side pouches”. “These form hemispherical, or, more properly, semioval evaginations of the gastral wall, and hang together in pairs in such a way that eight pairs appear as oral bifurcated terminal shoots of the eight gastral grooves”Short, broad, square, slightly longer than the peduncle, with thick muscular walls. Gastric peduncle and manubrium taken together about half the height of the sumbumbrella cavity. Manubrial cavity divided into eight longitudinally folded gastric pouches that open into the radial canals. The presence of septal pouches presumably increases the absorption surface of the endoderm.“Oral margin Feshy and thickened, quadrate, with four radial oral tentacles” (sic!). “These folds are divided into four interradial groups by four perradial longitudinal muscles, ending in the four short heart-shaped oral lobes”Mouth with four prominent, elongated perradial lips, and swollen interradial edgesGonads“The eight genitalia […] are wide, folded, thick-walled pouches, which occupy the proximal half of the radial canals”8, extending along the proximal half of the radial canals; Fattened, with distal part free and slightly pendantNematocyst ring“Umbrella margin, thickened into a roll”Bell margin thickened by a conspicuous ring of cnidocystsVelum“The velum […] is distinguished by a very unusual development of the muscular system”, and is characterized by the presence of “numerous highly-developed circular folds”. “The breadth of the velum is so great that when fully extended it can probably close the entire umbrella cavity like a sphincter”Wide, with marked circular musclesTentacles“The numerous sucking-cups (sic!) form 6 to 8 alternating rows placed one above the other on the umbrella margin; in each of the thirty-two small groups, which have an almost rhomboidal outline, they are placed in 5 to 6 diagonal rows, each with 4 to 5 tentacles”; “about a thousand”. Types, shapes and arrangement well- illustrated in Haeckel’s Pl. 3 Fig. 12.About 1200 per medusa, ca 150 per octant, superimposed in 5–6 rows; their size increases from the adaxial to the abaxial side 2 types of tentacles: solid, with adnate base in the outermost row, and shorter and thinner in the innermost rowsStatocysts“The auditory clubs (sic!) […] lie on the axial side of the umbrella margin, under the insertion of the velum, inside the lowest row of tentacles. After most careful search, I was only able to discover two or three of them, very small”Numerous, free, placed among the marginal tentacles; with single, large statoliths

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Metrics

Dataset Index

1.8

FAIR Score

85%

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2

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0

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Publication Details

DOI

Publisher

Zenodo

Assigned Domain

Subfield

Pollution

Field

Environmental Science

Domain

Physical Sciences

Confidence Score

97%

Source

Open Alex

Keywords

BiodiversityTaxonomy

Normalization Factors

FT

30.77

CTw

1.00

MTw

1.00