. Bulletin. Natural history; Natuurlijke historie. I I. Fig. 8. —Spicules of Microciona rarispinosa. A. Stout subtylostyles. B. Thin subtylostyle. C. Heads of stout tylostyles enlarged to show spination. D. Palmate isochelas. E. Toxa. A, B: scale I. C, D: scale II. E: scale III. YPM 5041. Holotype. are only 1-3 in number and usually less than I /a in height, (b) Thin, scattered sub- tylostyles, with narrow ovoid heads, 116-608 X 2-5 ju,. (c) Narrow palmate isochelas, 12-20 [X long, with a maximum head width of 3 jx- (d) Toxas 16-23 x 2 ju, or less. Most are tricurvate, with a wide deep arch, a
. Bulletin. Natural history; Natuurlijke historie. I I. Fig. 8. —Spicules of Microciona rarispinosa. A. Stout subtylostyles. B. Thin subtylostyle. C. Heads of stout tylostyles enlarged to show spination. D. Palmate isochelas. E. Toxa. A, B: scale I. C, D: scale II. E: scale III. YPM 5041. Holotype. are only 1-3 in number and usually less than I /a in height, (b) Thin, scattered sub- tylostyles, with narrow ovoid heads, 116-608 X 2-5 ju,. (c) Narrow palmate isochelas, 12-20 [X long, with a maximum head width of 3 jx- (d) Toxas 16-23 x 2 ju, or less. Most are tricurvate, with a wide deep arch, and recurved ends. The smaller toxas have a shal- low arch and straight ends. Individual analyses, lengths in microns: Thick Tylostyles 128-702 (50) 72-398 (50) 82-538 ^5)" Thin Tylostyles 153-375 (50) 116-348 (50) 146-608 (50)* Isochelas 13-16 (50) 12-15 (25) 13-20 (25)^ Toxas 16-60 (50) 20-44 (,25) 20-63 (50)" Discussion. The species is characterized by a lack of acanthostyles, and the near absence of shaft spination on the echinating megascleres. It is therefore intermediate between Microciona and the ophlitaspongiid genus Axociella. In spicule size ranges the present species is very similar to the Puerto Rican sponges described as Microciona spinosa by Wilson (1902a). Wilson's species differs by its complete lack of spination and by the presence of conules. De Laubenfels (1936a, p. 113) transferred M. spinosa to Axociella. De Laubenfels' Florida specimens differ from Wilson's in shape, spicule complement and megasclere distribution. They are therefore unlikely to be conspecific with either the Puerto Rican or Jamaican sponges. Microciona similis Stephens (1915) of South Africa is also similar in structure to the Jamaican species but differs in having thicker fibers and larger toxas. The smallest styles have a considerable number of spines on the shaft. De Laubenfels (1936a) established a. Please note that these images are extracted from scanned page images that m
Size: 3212px × 778px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookcollectionbiodiv, booksubjectnaturalhistory
