Bolocera kensmithi, Fautin, 2012

Fautin, D. G., 2012, Taxonomy and distribution of sea anemones (Cnidaria: Actiniaria and Corallimorpharia) from deep water of the northeastern Pacific, Zootaxa 3375, pp. 1-80 : 10-15

Bolocera kensmithi n. sp.

( Figures 5–8, Table 1, Appendix 4)

Body form and size. Column tan or pink, smooth, ectoderm typically slightly wrinkled. Column stiff but not thick (about 0.5 mm); mesenterial insertions typically visible along entire length, most evident at limbus and margin. In some preserved specimens mesenteries protrude from proximal end of column or pedal disc ( Figure 5).

Most animals contracted so margin partially covers insertion of tentacles. Column short (10–31 mm long), in

Tentacles deciduous (characteristic of genus): circumscribed endodermal sphincter muscle at base of each tentacle. All specimens devoid of tentacles.

Pedal disc. Tan to pink, wrinkled or smooth. Circular, slightly concave; about half diameter of oral disc.

Oral disc and tentacles. Oral disc tan to reddish-purple; smooth in poorly-preserved specimens, radially furrowed along mesenterial insertions in well-preserved specimens. In most specimens, oral disc torn, and mesenteries protrude through mouth. Mouth large (about 2/3 diameter of oral disc, opening to 18 mm); radially furrowed, lips raised and very prominent when mouth not torn (to 5 mm wide and long). Two prominent, symmetrical, off-white siphonoglyphs apparent in specimens with intact oral disc.

Number and arrangement of tentacles inferred by pores (to about 2 mm diameter) on oral disc; small ridge typically surrounds each pore. To 72 pores, about 48 in most specimens, arrayed in three or four cycles; those of inner cycles communicate with endocoels, those of outermost cycle communicate with exocoels.

Internal anatomy. Actinopharynx tan to deep purple, longitudinally furrowed; protruded in most specimens, nearly same length as column. Each of two long symmetrical siphonoglyphs attached to pair of directive mesenteries.

Mesenteries thick and muscular, hexamerously arrayed in three cycles; typically more numerous at limbus than at margin (e.g. 56 vs. 48). Rare quaternary mesenteries occur in pairs between mesenteries of second and third cycles (i.e. 11 44 3344224433 44 11: bolded 4s represent position of quaternary mesenteries absent in most specimens examined). First to third cycle complete; youngest complete mesenteries reach actinopharynx only at distal end. Incomplete mesenteries lack filaments. Oral stomata large, marginal stomata small. Directives and some members of youngest cycle sterile; all other mesenteries fertile. Sexes separate; ova to about 1.5 mm diameter.

Retractor muscles strong and diffuse ( Figure 6a); in some specimens may be lobed. Parietobasilar muscles with no pennons or short detached ones.

Diffuse endodermal marginal sphincter muscle poorly developed; lamellae short to moderately long (Figure

6b).

Cnidae. Basitrichs, microbasic p -mastigophores; presumably spirocysts are present in tentacles, but all specimens examined lacked tentacles. Sizes and distribution of cnidae given in Table 1; cnidae illustrated in Figure 7.

Type specimens. Holotype: KUIZ 003252 , collected 6-Apr-2003 from 49.35– 49.33° N 127.55– 127.52° W, 1,804–1,827 m. Column length 25 mm, oral disc diameter 40 mm, and pedal disc 22 mm. Third cycle of mesenteries developed, fourth cycle partially developed with same number of tentacle pores.

Paratypes: CAS 184529 , 4 specimens collected 5-Jun-1996 from 34.67° N 123.18° W, 4,100 m ; USNM 1149361 , 1 specimen collected 14-Nov-1995 from 34.70° N 123.03° W, 4,100 m ; KUIZ 001522 , 1 specimen collected 29-Jan-1996 from 34.72° N 123.22° W, 4,100 m ; SBMNH 149659 , 1 specimen collected 17-Oct-1992 from 34.77° N 123.13° W, 4,100 m ; RBCM 010-00573 - 001 , 1 specimen collected 15-Apr-2003 from 49.71– 49.71° N 127.95– 127.96° W, 2,003 –2,091 m.

Etymology. Named in honor of Kenneth L. Smith, Jr., who collected specimens of this species, as well as many other deep-sea anemones, from Station M off the coast of California.

Material examined. See Appendix 4.

Differential diagnosis. The only other species of Bolocera known from the northeastern Pacific is B. pannosa McMurrich, 1893 , which has a large, convex oral disc covered by about 400 tentacles, and an oral disc that conceals the short column, is easily separated from B. kensmithi n. sp. Bolocera kensmithi n. sp. can be distinguished from its congeners by its combination of: concave pedal disc; column that tapers from the widest part distally to the narrowest part proximally; about 48 tentacles arrayed in four cycles; 24 pairs of mesenteries arrayed in three cycles (plus occasionally a few pairs of a fourth cycle); directive mesenteries sterile; marginal stomata.

Dichotomous key to species of Bolocera (except Bolocera maxima , described by Carlgren [1921] from off Greenland based solely on tentacles, and therefore distinguished by its nematocysts, for which we lack comparable data for B. kensmithi n. sp.).

1 Column so short margin almost touches limbus, oral disc broad and convex....................................... 2

- Column not short, either cylindrical or wider at distal than at proximal end, margin not near limbus.................... 3

2 About 400 flaccid slender tentacles to 37 mm long arrayed in seven cycles. Pedal disc oval (70 x 25 mm diameter in average specimen) and thin; mesenterial insertions visible. Northeastern Pacific Ocean.............. B. pannosa McMurrich, 1893

- About 150 blunt digitiform tentacles to 20 mm long scattered over oral disc. To five cycles of mesenteries; oral and marginal stomata present. Pedal disc circular, slightly larger diameter than proximal end of column. Two size classes of basitrichs in actinopharynx. Southern Ocean..................................................... B. paucicornis Dunn, 1983

3 Marginal sphincter muscle well developed................................................................. 4

- Marginal sphincter muscle poorly developed............................................................... 5

4 Column approximately twice as long as diameter of oral and pedal disc in preserved specimens; tentacles arrayed in four cycles. Off East Africa................................................................ B. africana Pax, 1909

- Column thin, same length as diameter of oral disc in preservation. About 200 long, conical, and longitudinally furrowed tentacles arrayed in five or six cycles. Northern Atlantic Ocean............................ B. tuediae ( Johnston, 1832)

5 All mesenteries fertile except for directives and some of youngest cycle......................................... 6

- Mesenteries of first cycle, and some of second cycle sterile; 96 pairs of mesenteries total, 48 pairs complete. About 180 tentacles. Off East Africa....................................................... B. somaliensis Carlgren, 1928a

6 Mesenteries lack oral and marginal stomata. To five cycles of thin mesenteries equally developed along column; parietobasilar muscles with large detached pennons. Tentacles (to about 100) arrayed in as many as seven cycles. Basitrichs of mesenterial filaments to 64 µm long, one size class of basitrichs in column. South of 30° S ............... B. kerguelensis Studer, 1879

- Mesenteries possess oral and marginal stomata. 24 pairs of thick mesenteries arrayed in three cycles (plus rarely a few pairs of a fourth cycle), develop from proximal end; parietobasilar muscles with small detached pennons or without pennons. About 48 tentacle pores (correspond to number of tentacles in life) arrayed in four cycles near margin. Pedal disc circular. Basitrichs of mesenterial filaments to 73 µm long; two size classes of basitrichs in column. Northeastern Pacific Ocean...................................................................................................... B. kensmithi n. sp.