Chiropsoides buitendijki ( Horst 1907 )

Gershwin, Lisa-Ann, 2006, Comments on Chiropsalmus (Cnidaria: Cubozoa: Chirodropida): a preliminary revision of the Chiropsalmidae, with descriptions of two new genera and two new species, Zootaxa 1231 (1), pp. 1-42 : 18-22

Chiropsoides buitendijki ( Horst 1907)

Plates 3A–D , 5 B–C

Chiropsalmus buitendijki Horst, 1907: 101–106 , pl. 2, figs. 1–6. — Mayer, 1910: 515. — Stiasny, 1919: 46–47, text figs. 12–14; examination of type specimens, plus 3 additional. — Menon, 1930: 4–5; Madras. — Rao, 1931: 29; curiously not found. — Menon, 1936: 3; Krusadai Island, India. — Ranson, 1945: 314; Indochina. — Nair, 1951: 71, Trivandrum Coast, India. — Kramp, 1959: 16, comparison with C. quadrumanus . — Kramp, 1961: 309. — Fernando, 2001: 140; Sri Lanka, earlier reports attributed to Chiropsalmus quadrumanus were inaccurate.

Drepanochirus buitendijki — Krumbach, 1925: 565–571, 575, fig. 531. — Uchida, 1929: 182, noted in classification. — Dawydoff, 1936: 471; Indochina, extremely rare. — Southcott, 1956: 276, genus preoccupied for Coleoptera .

Chiropsoides buitendijki — Southcott, 1956: 276. — Southcott, 1963: 49; comparison with Chironex . — Gershwin, 2005: 126, pl. 4.10A, B and throughout; taxonomy and phylogeny.

‘ Chiropsalmus quadrumanus . — Fernando, 1992: 75–76; stings in Sri Lanka; later identified as C. quadrigatus [non Chiropsalmus quadrumanus ( Müller, 1859) ].

‘ Chiropsalmus quadrigatus . — Fernando, 1994: 58; stings in Sri Lanka [non Chiropsalmus quadrigatus Haeckel, 1880 ].

non Chiropsalmus buitendijki . — Stiasny, 1926: 249, Bowen Harbour, QLD, Australia [= Chironex fleckeri Southcott, 1956 ]. — Pope, 1953: 111, presence in Australia. — Payne, 1960: 6; Australia.

Type locality From the harbor of Batavia, Java.

Material examined

Syntype: RMNH 5234 , Reede van Batavia, Java, P. Buitendijk, 1907; 2 specimens, A) gravid female, BH 64.21mm, DBW 86.60mm, IRW 46.38mm, TBW 3.46mm; B) BH 64.56mm, DBW 88.72mm, IRW 48.78mm, TBW 3.42mm .

Other material: RMNH 5235 , Reede van Batavia, Java, P. Buitendijk, 1908–1909 . QM G317021 , Mt. Lavinia , Sri Lanka, 12 September 1993; 79.84mm BH, 85.26mm DBW, 41.09mm IRW, 1.80mm TBW, 9­tentacle stage . QM G317032 , no data, 58.91mm BH, 92.08mm DBW, 41.69 IRW, 7­tentacle stage .

Revised diagnosis

Chiropsoides with 5–9 fingers and tentacles; with long, hollow, finger­shaped gastric saccules; with low, pyramidal diverticulae on the main shafts of the pedalial canals, singly between successive branches.

Revised description, primarily based on syntype specimen A

Bell small and quite cuboid, with a smoothly rounded apical dome ( Plate 3A ), with or without a shallow subapical coronal furrow (spec. A lacks it, spec. B has it). Mesoglea of a thick and rigid consistency, with noticeable thickenings on the apical dome and on the interradial pillars. Interradial furrows absent. Adradial furrows shallow in lower half, becoming indistinct in upper half, defining the interradial pillars. Exumbrellar texture smooth, lacking nematocyst warts or freckles; nematocyst clusters similarly not present on the pedalia or the velarium.

Pedalia 4, interradial, less than one half bell height, with 5 fingers and tentacles arranged in a linear series, decreasing in size sequentially, the smallest being the outermost ( Plate 3B ). The pedalium itself curls adaxially under the bell, but the branches arise in a single row along the abaxial surface. Fingers substantially flattened with the same axis as the pedalia, each narrowly scalpel­shaped. Pedalial canals flattened in cross section, with an extremely long, narrow, upward­pointing ‘spike’ into the sub­lamellar space, obscuring the canal bend. Abaxial edge of main shaft with a single shallow V­shaped convexity between successive tentacles; adaxial edge of main shaft and both edges of branches unadorned. Canal branches L­shaped or crescent­shaped overall, such that the tentacles arise from the side of the distal end of the fingers, rather than the actual terminal end. Canals not flared at tentacle insertion. Tentacles substantially flattened, ribbon­like, considerably larger in diameter than the pedalial canals with which they connect. Tentacle banding pattern could not be discerned due to breakage; none of the tentacles of the holotype are longer than about 1cm.

Rhopaliar niche ostia shallow oval­shaped, with a poorly defined lower covering scale and a shallowly­concave upper scale. Rhopaliar horns absent. Rhopaliar warts not examined. Eyes 6 per rhopalium, with 2 median lensed eyes, with 4 lateral pigment spots.

Velarium broad, with 2 velarial canals arising from the stomach but branching so profusely that the number of dendritic branches and lateral diverticulae is impossible to count accurately. Perradial lappets more or less equilaterally triangular, extending about three­fourths the distance to the velarial edge; with side branches and distal branches. Frenulae narrowly developed, extending only about half the distance to the velarial margin; with conspicuous perforations down the midline. The number of frenular sheets was not noted during examination of the type specimens, but later examination of rhopaliar niche and velarial photographs reveals that they are thick where they connect to the perradial lappets and approach the rhopaliar niche; thus, they either are a solid gelatinous sheet, or are a hollow structure with two sheets. In specimen RMNH 5235, the frenulae are comprised of double sheets.

Phacellae of the typical Chirodropida form, i.e., V­shaped corner masses; cirri unbranched and singly rooted. Lateral gonads well developed, leaf­shaped along almost the full height of the bell, broader in the upper half. Interradial perforations lacking. Superior gonads well developed, enveloping the saccules, especially conspicuous around the distal half. Gastric saccules ( Plate 3C ) comprising 8 long hollow finger­shaped projections, arising singly from each side of the perradii on the uppermost part of the subumbrellar bell wall; reaching to about the height of the velarium. Manubrium very short, about one­fourth as long as the saccules, cruciform with thickened corners. Mouth with recurved, smooth­edged, folded, tongue­shaped lips. Mesenteries only rudimentarily developed in the uppermost parts of the stomach region, not extending down the bell wall as either flap­like or cord­like structures. Rhopalial window shape not examined.

Colour in life unknown; preserved, the body is hyaline, and the gonads and tentacles are pale pinkish, apparently from preservation.

Variation

The QM specimens are at a similar body size, but differ in several major characters from the Javanese specimens. The Sri Lankan specimen G317021 has nine ‘fingers’ on the pedalia, and about 13 velarial canals per octant reaching the margin, with the lateral diverticula being secondarily diverticulated with a spiky appearance ( Plate 3D ). The specimen G317022 from an unknown locality has seven ‘fingers’ on the pedalia, and broadly rounded velarial canals. Both QM specimens have fine, round tentacles.

Distribution

Originally described from Java, it has since been reported from the Malay Archipelago ( Stiasny 1919), India ( Menon 1936; Nair 1951; Chakrapani 1984), and Indochina ( Dawydoff 1936; Ranson 1945). Reports from Australia were erroneous ( Stiasny 1926; Pope 1953; Payne 1960); see below.

Nematocysts

The tentacular cnidome from one of the syntype specimens comprised two types ( Plate 5B ): elongate club­like microbasic p ­mastigophores (85.95–94.14µm long x 11.14–14.55µm wide, n=12), and large oval microbasic p ­mastigophores (37.31–41.43µm long x 16.01–17.86µm wide, n=16). No other nematocyst types were observed.

The tentacular cnidome of QM 317021 from Sri Lanka comprised five types: 1) hockey­stick­shaped microbasic p ­mastigophores (60.79–78.92µm long x 9.51–11.78µm wide, n=11; Plate 5C ); 2) small football­shaped isorhizas with a beehive­form tubule, 9.26–11.26µm long x 7.39–8.30µm wide, n=6; 3) small rod­shaped isorhizas, 14.34–15.25µm long x 3.76–4.22µm wide, n=3; 4) small spherical isorhizas, 6.97–9.71µm diameter, n=11; and 5) very small spherical isorhizas (3.53–4.21µm diameter, n=8) .

Remarks

It is not yet clear whether the Burmese Chiropsoides quadrigatus comb. nov. and Javanese Chiropsoides buitendijki should be regarded as the same species. Logic would hold that they might not be identical based on the geographical separation between the two forms. Furthermore, the holotype of C. quadrigatus has immature gonads and almost the same number of tentacles at only a fraction smaller body size than the C. buitendijki syntypes have at full maturity, leading one to think that perhaps they mature at different sizes (and perhaps different anatomical characteristics). However, until the juvenile stages of C. buitendijki from Java and the adult stages of C. quadrigatus from Rangoon become known and are compared, it would be misleading to conclude with certainty on the relationship between the two forms.

It is also possible that the Sri Lankan form is the adult form of the enigmatic C. quadrigatus , or this may represent a different species altogether. I have only had opportunity to study two specimens from Sri Lanka, both have nearly twice the number of pedalial branches at a smaller body size than the Javanese specimens, and the Sri Lankan velarial canals have a peculiar ‘spiky’ appearance, whereas the velarial canals of the Javanese specimens are broader and more rounded .

Note of correction to the scientific literature

Stiasny (1926) reported on Chiropsoides buitendijki (as Chiropsalmus buitendijki ) collected in Queensland. I have examined the specimens in question, which are housed at the Australian Museum ( AM G13099, lot of 3), and can confirm without doubt that they are Chironex fleckeri , not Chiropsoides buitendijki . All three specimens are in poor condition, but the pedalia unmistakably fork in both directions, unlike C. buitendijki , in which the pedalia fork serially and uni­directionally. Furthermore, the pedalial canals spike in the typical Chironex fashion, instead of the very long narrow spike of C. buitendijki or the knee­shaped bend of the common Australian “ Chiropsalmus ”.

Figures

PLATE 3. Chiropsoides spp. A. Chiropsoides buitendijki, syntype specimen, preserved. B. C. buitendijki, pedalium. C. C. buitendijki, gastric saccules (arrow). D. C. buitendijki, Sri Lanka, velarial canals. E. C. quadrigatus, holotype, preserved. F. C. quadrigatus, pedalium; note bulge on canal (arrow).

PLATE 5. Primary tentacular nematocysts. A. Chiropsalmus quadrumanus, neotype, club­form microbasic p­mastigophore (a), large oval microbasic p­mastigophore (b), spherical microbasic p­ mastigophore (c), and straight­sided isorhizas (d). B. Chiropsoides buitendijki, syntype, elongate club­form microbasic p­mastigophore above, large oval microbasic p­mastigophore below. C. Chiropsoides buitendijki, non­type specimen from Sri Lanka (QM 317021), microbasic p­ mastigophore; note ‘hockey­stick’ shape.