Acryptolaria angulata ( Bale, 1914 )

Peña Cantero, Alvaro L., Marques, Antonio C. & Migotto, Alvaro E., 2007, Revision of the genus Acryptolaria Norman, 1875 (Cnidaria, Hydrozoa, Lafoeidae), Journal of Natural History 41 (5 - 8), pp. 229-291 : 235-237

Acryptolaria angulata ( Bale, 1914)

( Figures 2 , 17B ; Table II)

Cryptolaria angulata Bale 1914, p 166 –167, Plate 35 Figure 1 ; 1915, p 251; Stranks 1993, p 7.

Acryptolaria angulata: Schuchert 2003, p 155 –156, Figure 14 .

Not Acryptolaria angulata: Vervoort 1966, p 116 –117, Figure 16 [5 A. rectangularis ( Jarvis, 1922) ].

Not Acryptolaria angulata: Hirohito 1995, p 102 , Figure 29a, b, Plate 6 Figure B [5 A. bulbosa ( Stechow, 1932) ].

Material examined

Holotype: three microslides from the Museum of Victoria, Melbourne , MV F58335 .

Description

‘‘Hydrophyton about three inches in height [76.2 mm], branched and re-branched in one plane; branches irregular, neither opposite nor alternate, slender, fascicle-tubes not numerous’’ ( Bale 1914, p 166).

Hydrothecae alternately arranged approximately in one plane. Hydrotheca mostly cylindrical, but with two distinct constrictions due to sharp perisarc invaginations, narrowing hydrothecal diameter which, in any case, is smaller at the adnate part; diameter also decreasing at basal part. Hydrotheca curved twice: strongly abcaulinarly at distal part of adnate portion and slightly upwards just after the adnate wall becomes free. Abcauline wall straight but strongly inflected at approximately half of its length and provided with a sharp invagination at that point; basal half parallel to longitudinal axis of branch, distal half forming an angle of ca 70 ° with that axis. Adcauline wall adnate for approximately half its length, though hydrothecae with free part longer or shorter than adnate part also present. Adcauline wall convex at adnate part, with a strong invagination at approximately half of its length. Hydrothecal aperture circular, oblique, upwardly directed. Rim even, sometimes with several short renovations.

Coppinia not observed.

Remarks

All material examined consisted of microslide preparations, making it difficult to find nematocysts. However, at least one category of nematocyst is present.

Although the material studied is in three whole-mount preparations, we believe it belongs to a single colony, as there is no indication that the original description ( Bale 1914) was based on more than one colony. Therefore, we considered the three slides as parts of the holotype.

Bale (1914, p 166) characterized this species by the ‘‘sharply geniculate outward bend, with the noticeable crease in the angle, also by the distinct boss projecting into the hydrothecal cavity, opposite the crease. Immediately after the bend the axis of the hydrotheca is at a right angle with that of the lower portion, but it usually bends a little upward again, so that the distal half is not horizontal but slightly ascending’’. The distinct adcauline invagination of perisarc was also found by Vervoort (1966) examining a slidemounted specimen, which he believed to be Bale’s schizosyntype or schizoparatype, and by Schuchert (2003), who also examined type material of Acryptolaria angulata (three slides belonging to syntype).

Although the species A. angulata , A. bulbosa , and A. rectangularis share some similarities, we regard them as valid. However, confusion concerning these species may be found in the literature. At least two records of A. angulata refer to different species: Hirohito’s (1995) material, lacking the adcauline invagination, is here considered referable to A. bulbosa (see below), and the material described by Vervoort (1966) is here considered as A. rectangularis (see below).

Distribution

Acryptolaria angulata has been collected at depths from 180 ( Bale 1914) to 324 m ( Bale 1915) on bottoms of sandy mud and small stones ( Schuchert 2003). At present, it is known only from the Great Australian Bight ( Bale 1914, 1915) and the Kei Islands, Indonesia ( Schuchert 2003).

Figures

Figure 1. Acryptolaria abies (Allman, 1877). (A) Part of branch showing hydrothecal arrangement; (B–F) hydrothecae. (A–C, E) From the paralectotype; (D) from the lectotype; (F) from MCZ 45714. Scale bar: 1 mm (A); 400 Mm (B–F).

Figure 2. Acryptolaria angulata (Bale, 1914). (A–C) Hydrothecae. All drawings from the holotype. Scale bar: 400 Mm.

Figure 14. Acryptolaria tortugasensis Leloup, 1935. (A–F) Branch fragments showing shape and arrangement of hydrothecae. All drawings from the holotype. Scale bar: 1 mm (A); 400 Mm (B–F).

Figure 16. Hydrothecal arrangement in Acryptolaria (continued). (A) A. longitheca; (B) A. minima; (C) A. minuta; (D) A. operculata; (E) A. pulchella; (F) A. tortugasensis. Scale bar: 500 Mm (A, D); 250 Mm (B, C, E, F).

Figure 17. Shape of hydrotheca in Acryptolaria. (A) A. abies; (B) A. angulata; (C) A. conferta; (D) A. corniformis; (E) A. crassicaulis; (F) A. flabellum. Scale bar: 250 Mm.