Axinyssa ambrosia ( De Laubenfels, 1936 ),

Van, Rob W. M., 2017, Sponges of the Guyana Shelf, Zootaxa 1, pp. 1-225: 181

publication ID

http://doi.org/ 10.5281/zenodo.272951

publication LSID

lsid:zoobank.org:pub:6D68A019-6F63-4AA4-A8B3-92D351F1F69B

DOI

http://doi.org/10.5281/zenodo.3511283

persistent identifier

http://treatment.plazi.org/id/03A80010-77E3-FF18-FF14-A0BB92B6F856

treatment provided by

Plazi

scientific name

Axinyssa ambrosia ( De Laubenfels, 1936 )
status

 

Axinyssa ambrosia ( De Laubenfels, 1936) 

Figures 113View FIGURE 113 a –b

Rhaphisia ambrosia De Laubenfels, 1936: 135  .

Axinyssa ambrosia  ; Díaz et al. 1993: 289, figs 5, 10; Zea et al. 2013: 495 View Cited Treatment , figs 1, 3A –C.

Material examined. RMNH Por. 9331, Guyana, ‘Luymes’ Guyana Shelf Expedition, station 65, 7.55°N 57.0833°W, depth 63 m, sandy bottom, 31 August 1970GoogleMaps  ; RMNH Por. 9999, Suriname, ‘ Snellius O.C.P.S. ’ Guyana Shelf Expedition, station F45, 6.4417°N 56.5467°W, depth 34 m, Van Veen grab, 7 May 1966GoogleMaps  .

Description. Three lobate-digitate fragments ( Fig. 113View FIGURE 113 a), presumably the upper parts of sponges partially buried in the sand, and two parallel developed, elongate cylindrical specimens ( Fig. 113View FIGURE 113 a1). Size of digitate fragments 5–8 cm high, 2–4 cm in diameter, of cylindrical specimens 20 cm long, 2.5 cm in diameter. Color (alcohol) pale orange-beige. Surface irregular, but optically smooth, somewhat ridged and grooved. No apparent oscules. Consistency firm to hard.

Skeleton. No ectosomal specialization. The choanosomal skeleton is confused but shows arrangement of the spicules in tracts directed towards the surface.

Spicules. Oxeas only.

Oxeas ( Figs 113View FIGURE 113 b,b1) fusiform, sharply pointed, lightly curved, in a large size range, but not divisible in size categories, 618– 784 –954 x 16 – 25.2 –34 µm.

Distribution and ecology. Guyana Shelf, Florida, Curaçao, Jamaica, Colombia, reefs and sand, at 18–85 m depth (Gyana Shelf 34–65 m).

Remarks. The present specimens conform to the description of Axinyssa ambrosia  as given by Díaz et al. (1993), who also assigned Dictyonella yumae Pulitzer-Finali, 1986  as a junior synonym. Subsequently, Zea et al. 2013 revised both species and concluded that there are small differences between the two and that they are distinct species. In their analysis they restricted the spicule sizes of Axinyssa ambrosia  to 490–941 x 4.8–23.8 µm. The Guyana shelf material has slight larger and thicker oxeas (up to 954 x 34 µm), but these fall short of the sizes quoted by Zea et al. 2013 for Axinyssa yumae  (up to 1121 x 37.4 µm). Although there are a few fusiform styles among the spicules of the present specimens, they are infrequent. In conclusion, the identity of the Guyana material is most likely to be A. ambrosia  and not A. yumae  .

RMNH

National Museum of Natural History, Naturalis

Kingdom

Animalia

Phylum

Porifera

Class

Demospongiae

Order

Halichondrida

Family

Halichondriidae

Genus

Axinyssa

Loc

Axinyssa ambrosia ( De Laubenfels, 1936 )

Van, Rob W. M. 2017
2017
Loc

Axinyssa ambrosia

Zea 2013: 495
Diaz 1993: 289
1993
Loc

Rhaphisia ambrosia

De 1936: 135