Caulleriella rodmani Blake 2021, new species

Caulleriella rodmani new species

Figures 6–7

urn:lsid:zoobank.org:act: C4AA5F36-4C99-4055-81C8-96D30D0316AA

Caulleriella sp. 1: Blake et al. 1987: C-2; Maciolek et al.1987a: D-2; Hilbig 1994: 194.

Material Examined. (70 specimens) Off New Jersey and Delaware, U.S. Mid-Atlantic ACSAR program, coll. Rosemarie Petrecca, Chief Scientist. Sta. 5: Cruise Mid-4, Rep. 2, 16 May 1985, 38°50.48ʹN, 72°33.19ʹW, 2080 m, holotype (USNM 1642603); Rep. 1, 16 May 1985, 38°50.46ʹN, 72°33.23ʹW, 2080 m, 2 paratypes (USNM 1642604); Cruise Mid-1, Rep. 3, May 1984, 38°36.88ʹN, 72°51.34ʹW, 2055 m, paratype (USNM 1642605); Cruise Mid-3, Rep. 1, 5 Dec 1984, 38°50.42ʹN, 72°, 33.04ʹW, 2085 m, (1, USNM 1642606); Cruise Mid-5, Rep. 1, 3 Aug 1985, 38°50.44ʹN, 72°33.18ʹW, 2077, 2 paratypes (USNM 1642607). Sta. 1: Cruise Mid-2, Rep. 3, 03 Aug 1984, 38°35.99ʹN, 72°52.87ʹW, 2194 m (1, USNM 1642608); Cruise Mid-4, Rep. 3, 17 May 1985, 38°35.88ʹN, 72°53.13ʹW, 2195 m, paratype (USNM 1642609). Sta. 2: Cruise Mid-2, Rep. 1, 03 Aug 1984, 38°35.77ʹN, 72°53.58ʹW, 2019 m (1, USNM 1642610); Cruise Mid-3, Rep. 3, 02 Dec 1984, 38°35.68ʹN, 72°53.69ʹW, 2015 m (3, USNM 1642611). Sta. 4: Cruise Mid-3, Rep. 3, 05 Dec 1983, 38°44.40ʹN, 72°41.08ʹW, 2105 m, 2 paratypes (USNM 1642612); Cruise Mid-4, Rep. 2, 16 May 1985, 38°44.45ʹN, 72°41.26ʹW, 2091 m, 2 paratypes (USNM 1642613); Cruise Mid-5, Rep. 1, 3 Aug 1985, 38°44.43ʹN, 72°41.24ʹW, 2095 m, paratype (USNM 1642614); Cruise Mid-6, Rep. 3, 11 Nov. 1985, 38°44.40ʹN, 72°41.26ʹW, 2105 m (1, USNM 1642615). Sta. 6: Cruise Mid-3, Rep. 3, 28 Nov 1984, 39°05.65ʹN, 72°03.08ʹW, 2085 m, 2 paratypes (USNM 1642616). Sta. 7: Cruise Mid-1, Rep. 3, 06 May 1984, 38°27.30ʹN, 73°03.43ʹW. 2100 m, (1, USNM 1642617); Cruise Mid-5, Rep. 2, 07 Aug 1985, 38°27.32ʹN, 73°03.54ʹW, 2095 m, paratype (USNM 1642618); Rep. 3, 07 Aug 1985, 38°27.31ʹN, 73°03.54ʹW, 2088 m, (2, USNM 1642619); Cruise Mid-6, Rep. 1, 14 Nov 1985, 38°27.29ʹN, 73°03.58ʹW, 2096 m, paratype (USNM 1642620). Sta. 8: Cruise Mid- 1, Rep. 1, 06 May 1984, 38°27.36ʹN, 73°05.09ʹW, 2148 m, paratype (USNM 1642621); Rep. 3, 06 May 1984, 38°27.36ʹN, 73°04.81ʹW, 2150 m, paratype (USNM 1642622); Cruise Mid-2, Rep. 1, 05 Aug 1984, 38°27.21ʹN, 73°04.79ʹW, 2159 m (1, USNM 1642623); Cruise Mid-3, Rep. 3, 01 Dec 1984, 38°27.15ʹN, 73°04.79ʹW, 2155 m, 2 paratypes (USNM 1642624). Sta. 9: Cruise Mid-3, Rep. 1, 30 Nov. 1984, 38°17.20ʹN, 73°14.38ʹW, 2110 m (1, USNM 1642625); Cruise Mid-4, Rep. 2, 18 May 1985, 38°17.20ʹN, 73°14.65ʹW, 2105 m, paratype (USNM 1642626). Cruise Mid-5, Rep. 1, 08 Aug 1984, 38°17.24ʹN, 73°14.63ʹW, 2100 m, 2 paratypes (USNM 1642627); Cruise Mid-6, Rep. 1, 16 Nov 1985, 38°17.24ʹN, 73°14.92ʹ, 2108 m, (1, USNM 1642628). Sta. 10: Cruise Mid-4, Rep. 2, 19 May 1985, 37°51.75ʹN, 73°19.97ʹW, 2095 m, paratype (USNM 1642629). Sta. 11, Cruise Mid-5, Rep. 3, 06 Aug 1985, 38°40.14ʹN, 72°56.46ʹW, 1502 m, (1, USNM 1642630). Sta. 12: Cruise Mid-1, Rep. 1, 8 May 1984, 38°29.34ʹN, 72°42.23ʹW, 2501 m, paratype (USNM 1642631); Rep. 2, 8 May 1984, 38°29.33ʹN, 72°42.19ʹW, 2500 m, paratype (USNM 1642632); Cruise Mid-6, Rep. 3, 14 Nov. 1985, 38°29.22ʹN, 72°42.33ʹW, 2499 m, paratype (USNM 1642633).— Off New Jersey, U.S. EPA DWD-106 Site Survey, Sta. G, Rep. 3, 18 Nov 1985, 38°55.60ʹN, 72°02.62ʹW, 2509 m (2, MCZ 161720).— Off New England, U.S. North Atlantic ACSAR program, coll. G.W. Hampson, Chief Scientist. Sta. 3: Cruise NA-2, Rep. 1, 25 Apr 1985, 41°01.38ʹN, 66°20.18ʹw, 1340 m, 3 paratypes USNM 1642634). Sta. 5: Cruise NA-3, Rep. 2, 04 Jul 1985, 40°05.08ʹN, 67°29.85ʹW, 2060 m, (1, USNM 1642635); Cruise NA-4, Rep. 1, 25 Nov 1985, 40°05.06ʹN, 67°29.86ʹW, 2074 m (1, USNM 1642636); Rep. 3, 25 Nov 1985, 40°05.07ʹN, 67°29.81ʹW, 2071 m (1, USNM 1642637); Cruise NA-5, Rep. 1, 29 Apr 1986, 40°05.06ʹN, 67°29.94ʹW, 2052 m, paratype (USNM 1642638); Sta. 6: Cruise NA-1, Rep. 1, 05 Nov 1984, 40°05.09ʹN, 67°29.23ʹW, 2117 m, paratype (USNM 1642639); Cruise NA-2, Rep. 1, 29 Apr 1985, 40°05.04ʹN, 67.° 29.99ʹW, 2108 m, paratype (USNM 1642640); Rep. 2, 25 Apr 1985, 40°05.03ʹN, 67°29.13ʹW, 2108 m (1, USNM 1642641); Rep. 3, 25 Apr 1985, 40°05.06ʹN, 67°29.13ʹW, 2107 m, paratype (USNM 1642642). Sta. 8: Cruise NA-1, Rep. 1, 10 Nov 1984, 40°10.37ʹN, 67°37.43ʹW, 2175 m, paratype (USNM 1642643); Cruise NA-4, Rep. 1, 25 Nov 1985, 40°10.21ʹN, 67°37.24ʹW, 2184 m (1, USNM 1642644); Cruise NA-5, Rep. 2, 25 Nov. 1985, 40°10.25ʹN, 67°37.33ʹW, 2179 m (1, USNM 1642645). Sta. 9: Cruise NA-2, Rep. 1, 03 May 1985, 39°50.43ʹN, 70°01.58ʹW, 1235 m (1, USNM 1642646); Rep. 3, 03 May 1985, 39°50.42ʹN, 70°01.64ʹW, 1225 m (1, USNM 1642647). Sta. 10: Cruise NA-1, Rep. 2, 13 Nov 1984, 39°48.10ʹN, 70°05.29ʹW, 1234 m, paratype (USNM 1642648); Cruise NA-2, Rep. 3, 03 May 1985, 39°48.12ʹN, 70°05.24ʹW, 1210 m (2, USNM 1642649); Cruise NA-6, Rep. 3, 28 Jul 1986, 39°48.09ʹN, 70°05.29ʹW, 1228 m, 2 paratypes (USNM 1642650). Sta. 13: Cruise NA-6, Rep. 3, 30 Jul 1986, 39°48.25ʹN, 70°54.28ʹW, 1273 m, 2 paratypes (USNM 1642651). Sta. 14: Cruise NA-2, Rep. 2, 05 May 1985, 39°40.93ʹN, 70°54.21ʹW, 2092 m (2, USNM 1642652). Sta. 15: Cruise NA-2, Rep. 2, 05 May 1985, 39°40.07ʹN, 70°54.27ʹW, 2145 m, 2 paratypes (USNM 1642653); Cruise NA-5, Rep. 3, 06 May 1986, 39°40.10ʹN, 70°54.31ʹW, 2140 m, paratype (USNM 1642654).— Southeastern USA, U.S. South Atlantic ACSAR program, Off Cape Fear, North Carolina, coll. J.A. Blake, Chief Scientist. Sta. 12: Cruise SA-5, Rep. 1, 22 Sept 1985, 33°99.36ʹN, 76°97.27ʹW, 2004 m, paratype (USNM 1642655).

Description. A small, threadlike species; most specimens between 2.5 and 7 mm long. Holotype complete, 5.15 mm long, 0.07 mm across peristomium, 0.05 across far posterior setigers, with 24 setigers; large paratype a male, (USNM 1642634) complete in two parts, 7.27 mm long, 0.12 mm wide across peristomium, with 31 setigers. First 3–5 segments short, narrow, oval in shape, up to 1.5 times long as wide (Figs. 6A, C, 7A–E); following segments becoming elongated, moniliform, up to three to five times as long as wide (Figs. 6A, C–D, 7A–B); last 2–3 segments narrowing, bearing rounded pygidial lobe (Figs. 6B, 7F). Body generally cylindrical in cross section, no evidence of dorsal or ventral grooves. Color in alcohol; opaque white, with no pigment on body; most specimens with few to many elongate dark fecal masses (pellets) in middle setigers (Fig. 7A–B).

Pre-setiger region narrow, tapering anteriorly, up to twice as long as wide. Prostomium, triangular, weakly set off from peristomium, conical tapering to narrow, apex (Figs. 6A, C, 7C–E); eyespots absent; nuchal organs narrow slits on posterior lateral margins of prostomium, difficult to observe with light microscope. Peristomium smooth, with no apparent annular rings (Fig. 6A, C). Dorsal tentacles arise from posterior margin of peristomium (Figs. 6A–B, 7A, C, E). First pair of branchiae on setiger 1 dorsal to notosetae (Fig. 6C); subsequent branchiae in same location; branchiae or stubs only rarely observed on small specimens. Dorsal tentacles and branchiae when present long, thin, weakly expanded apically.

Parapodia reduced with setae appearing to arise directly from body wall. Noto- and neuropodia distinctly separated from one another, separation not as wide in anterior segments. Capillaries present throughout; anterior notosetae numbering 3–4 per fascicle, longer than neurosetae, which number 2 or 3 per fascicle. Neuropodial bidentate hooks first present from setiger 3–6; hooks numbering one per fascicle at first, increasing to no more than two hooks over last 10–12 setigers, accompanied by 1–2 capillaries throughout. Notopodial bidentate hooks first present from far posterior setiger 21, with one hook at first, second hook present or absent in posterior-most segments; smallest specimens lacking notopodial hooks. Individual hooks with thickened, weakly curved shaft, tapering to bidentate tip with main fang and apical tooth each about same length (Fig. 6G); hood or sheath absent.

Far posterior segments narrowing to a rounded, bulbous pygidium (Figs. 6B, 7F); anal cirri absent.

Methyl Green staining. No pattern.

Remarks. The majority of 70 specimens identified as C. rodmani n. sp. from the U.S. Atlantic continental slope are small and rarely exceeded more than one specimen per 0.09 m 2 box core sample. The specimens are so thin that after being emptied from the sample vials into a clean Stender dish with alcohol, they can often only be located visually after a careful search; if specimens cannot be located, the entire dish needs to be searched using the stereomicroscope; the labels and cotton plugs may also need to be rinsed and examined.

The long, thin, fragile body of this species indicates it is meiofaunal in habitat and that most specimens were likely not retained on the 0.3-mm-mesh-sieves used in the ACSAR program. The largest paratype was the only specimen determined to be sexually mature; it is a male with numerous sperm packets in the coelom.

Caulleriella rodmani n. sp. is closely related to C. filiformia n. sp., another threadlike species with which it may occur. In C. rodmani n. sp. the first pair of branchiae arise on setiger 1, dorsal to the notosetae, whereas in C. filiformia n. sp. the first branchiae are lateral to the dorsal tentacles on the posterior margin of the peristomium, with the second pair on setiger 1 dorsal to the notosetae. Rounded or moniliform segments typically occur along the entire of body of C. filiformia n. sp., while only the first 3–5 thoracic segments of C. rodmani n. sp. are rounded. Two short anal cirri occur on the pygidial segment of C. filiformia n. sp., whereas the pygidium of C. rodmani n. sp. is rounded and lacks anal cirri. In addition, the bidentate hooks of the two species are different. In C. filiformia n. sp. the apical tooth is an extension of an ‘alate’ hood or flange on the convex side of the shaft, whereas in C. rodmani n. sp., the apical tooth directly emerges from the end of the shaft and is not associated with a hood or flange. The dark elongate fecal pellets found in the intestine on most specimens assist in recognition.

Etymology. This species is named for Dr. James E. Rodman, retired Program Director, Division of Environmental Biology, National Science Foundation. Dr. Rodman initiated the PEET (Partnerships for Enhancement and Expertise in Taxonomy) Program and provided funding to this author for the study of polychaetes and training of students.

Distribution. U.S. Atlantic continental Slope from off New England to North Carolina, 1210–2509 m.