Acyptolaria pulchella ( Allman, 1888 )

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 : 261-263

Acyptolaria pulchella ( Allman, 1888)

( Figures 13 , 16E , 18E ; Table XIII)

Cryptolaria pulchella Allman 1888 , p lvii, lxvii, lxviii, 40–41, Plate 19 Figures 2, 2a .

Material examined

Holotype: BMNH 1888.11 .13.28, H.M.S. Challenger, Sta.?, Honolulu, 20–40 fathoms (36–72 m), one stem ca 70 mm high, with coppiniae.

Description

‘‘Colony attaining a height of nearly three inches [76.2 mm], main stem irregularly branched, branches carrying regular, pinnately disposed, alternate ramuli’’ ( Allman 1888, p 40).

Stem strongly polysiphonic, quite straight basally, giving rise to branches alternately arranged in one plane, sometimes in two planes making an obtuse angle. Distal part of colony with indefinite branching pattern; some areas with alternate branching, others with irregular arrangement. Basal part of stem with branches originating at ca 45 °, but thereafter curving upwards.

Hydrothecae alternate, in one plane. Hydrotheca tubular, almost completely cylindrical; diameter only slightly decreasing at basal part. Hydrotheca gently curved abcaulinarly; four-fifths to three-quarters of adcauline wall adnate to internode. Adcauline wall entirely convex; abcauline wall concave. Hydrothecal aperture circular, directed upwards, forming an angle of 50–70 ° with long axis of branch. Rim even, with few short renovations.

Coppiniae without defensive tubes. Gonothecae fusiform, bottle-shaped, firmly aggregated. Diameter strongly decreasing at distal part forming a short distal neck bearing a circular aperture.

Remarks

‘‘The very regularly pinnate disposition of the ramuli, and the absolutely distichous and regular disposition of the hydrothecae, give to this species an aspect of considerable elegance. It is a strong growing form with rather close-set, stout, and short hydrothecae’’ ( Allman 1888, p 41). Although Allman (1888, p 41) indicated that the ‘‘gonosome [was] not known’’, the type material examined has coppinia and afforded us an opportunity to describe the reproductive structures. Acryptolaria pulchella is characterized by the relatively short and wide hydrothecae, adnate to the branches by most of its adcauline wall, and by the large nematocysts.

Distribution

Pacific Ocean, Hawaii, Honolulu , 36–72 m ( Allman 1888) .

Figures

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

Figure 13. Acryptolaria pulchella (Allman, 1888). (A) Branch fragment showing hydrothecal arrangement; (B–E) hydrothecae; (F) coppinia fragment (dorsal view); (G) gonotheca (lateral view). All drawings from the holotype. Scale bar: 1 mm (A); 400 Mm (B–G).

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 18. Shape of hydrotheca in Acryptolaria (continued). (A) A. gracilis; (B) A. longitheca; (C) A. minima; (D) A. operculata; (E) A. pulchella; (F) A. tortugasensis. Scale bar: 100 Mm (A, C, F); 250 Mm (B, D, E).