Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . lity and only previous record of E. superba is St Thomas, WestIndies (depth not given). It is a new record from South Africa. Opercularella sp. Fig. 2Description Several branched stems reaching 22 mm in height and growing on spongespicules. Stem branching sympodially, fascicled, giving ofT alternate hydrothecaefrom an axial tube, straight or very slightly geniculate, the two rows of hydro-thecae in one plane. Branches rather irregular, occasionally subaltemate andarising below every third and fourth hydrotheca, simila
Annals of the South African Museum = Annale van die Suid-Afrikaanse Museum . lity and only previous record of E. superba is St Thomas, WestIndies (depth not given). It is a new record from South Africa. Opercularella sp. Fig. 2Description Several branched stems reaching 22 mm in height and growing on spongespicules. Stem branching sympodially, fascicled, giving ofT alternate hydrothecaefrom an axial tube, straight or very slightly geniculate, the two rows of hydro-thecae in one plane. Branches rather irregular, occasionally subaltemate andarising below every third and fourth hydrotheca, similar to stem but unfascicledor lightly fascicled only, the two rows more or less in one plane. Stem andbranches either unsegmented or with a faint and very oblique node immediatelyabove the origin of each hydrotheca. Some solitary hydrothecae arising separatelyfrom hydro rhiza. Hydrotheca pedicellate. Pedicel shorter than hydrotheca and not clearlydemarcated from it (boundary only recognizable by attachment of hydranth base THE SOUTH AFRICAN MUSEUMS MEIRING NAUDE CRUISES 111. Fig. 2. Opercularella sp. Various hydrothecae and opercula, a solitary hydrotheca at bottom right. Scale in mm/10. 112 ANNALS OF THE SOUTH AFRICAN MUSEUM to hydrotheca), forming a very acute angle with stem and often pressed againstit at base, sometimes with one or two indistinct corrugations. Hydrothecatubular, asymmetrical and curved away from stem, with adcauline wall moreconvex than abcauline. Solitary hydrothecae less curved. No diaphragm of four or five fragile converging segments which are not sharplydemarcated from thecal absent. Measurements (mm) Pedicel, length 0,07-0,26 Hydrotheca, length abcauline . 0,35-0,54 maximum diameter . . 0,11-0,16 Remarks This material is unlike any other described species. It is perhaps closest toiClOpercularella spec. no. 2 of Vervoort (1966: 108), but diners from it in thecurved hydrothecae and the smaller number of opercular segment
Size: 1316px × 1899px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booki, booksubjectnaturalhistory
