Smittina acicularis, Figuerola & Gordon & Cristobo, 2018

Figuerola, Blanca, Gordon, Dennis P. & Cristobo, Javier, 2018, New deep Cheilostomata (Bryozoa) species from the Southwestern Atlantic: shedding light in the dark, Zootaxa 4375 (2), pp. 211-249 : 223

Smittina acicularis n. sp.

( FIg. 7 ; TAbLE 9)

Etymology. LATIN ‘ acicula ’, LITTLE NEEDLE, ALLUDINg TO THE PAIR OF ANgLED NEEDLE-LIKE PIVOTS.

Material examined. HΟlΟtype: CRBA-58261, STN PAT0209DR09, COLONY C. 15 MM LONg, 5 MM WIDE, ENCRUSTINg CORAL.

Description. COLONY ENCRUSTINg, UNILAMINAR; COLONY SIZE C. 15 MM LONg, 5 MM WIDE. AUTOZOOIDS HEXAgONAL TO RECTANgULAR, THE LATERAL WALL VISIbLE AS THIN RIDgES. FRONTAL WALL DENSELY PERFORATED bY ROUND PORES. PRIMARY ORIFICE WIDER THAN LONg, LYRULA SHORT AND bROAD, WITH STRAIgHT EDgE AND SHARPLY CUSPED CORNERS, OCCUPYINg MOST OF PROXIMAL bORDER OF ORIFICE. NO ORAL SPINES. PERISTOME WELL DEVELOPED AND SUbTUbULAR, WITH ELEVATED SLOPINg SIDES LIKE A bROAD-bASED CONE. AVICULARIUM SITUATED PROXIMAL TO A SMALL PERISTOMIAL PSEUDOSPIRAMEN; ROSTRUM NORMAL TO FRONTAL PLANE, ELONgATE; A PAIR OF ANgLED NEEDLE-LIKE PIVOTS; PALATE ALMOST ENTIRE, WITH A SMALL FORAMEN bELOW THE PIVOTS. OVICELL SLIgHTLY WIDER THAN LONg, CONVEX, PERFORATED bY VARIAbLY SIZED PORES.

Remarks. Smittina IS A DIVERSE gENUS WITH A WORLDWIDE DISTRIbUTION bUT, AMONg THE SUbANTARCTIC SPECIES, ONLY A FEW HAVE THE SUbORAL AVICULARIUM SITUATED PROXIMAL TO THE PERISTOME AND WITHOUT A PSEUDOSINUS LIKE THE PRESENT SPECIES. S. lebruni (WATERS, 1905), S. leptΟdentata HAYWARD & THORPE, 1990 AND S. mΟnacha (JULLIEN, 1888) HAVE A PERISTOME WITH A LARgE PROXIMAL FORAMEN AND THE LATTER SPECIES SHOW DIFFERENT TYPES OF SUbORAL AVICULARIA (WITH ROUNDED OR SPATULATE ROSTRUM). S. acicularis n. sp. CLOSELY RESEMbLES Smittina Οblita LóPEZ-GAPPA, 2002, WHICH WAS ALSO RECORDED FROM THE SOUTHWESTERN ATLANTIC bUT IN SHALLOWER WATERS (92–183 M). IT MAY bE DISTINgUISHED FROM IT IN HAVINg A gREATER PSEUDOPORE DENSITY (63–77 PER ZOOID COMPARED TO 35–46), A PROPORTIONATELY SMALLER PSEUDOSPIRAMINAL PORE, A bROADER EXPANSE OF PERISTOMIAL WALL AbOVE THE PSEUDOSPIRAMEN, AND MANDIbULAR PIVOTS INSTEAD OF A COMPLETE CROSSbAR. LóPEZ-GAPPA ALSO ILLUSTRATED A WIDER, MORE-SPATULATE AVICULARIUM PRESENT IN SOME ZOOIDS OF S. Οblita bUT WHICH HAS NOT bEEN ENCOUNTERED IN S. acicularis n. sp.

n, number of measurements made; SD, standard deviation

Figures

FIGURE7. Smittinaacicularis n. sp., HOLOTYPE.A–B, PORTION OF ACOLONY;C,DETAIL OF THE PRIMARY ORIFICE WITH LYRULA;D, DETAIL OF THE OVICELL;E, DETAIL OF AN ELONGATED AVICULARIUM.SCALE bARS:A, 500 ΜM;B, 200 ΜM,C–D, 100 ΜM;E, 50 ΜM.