Reinhardorhynchus ruffinjonesi (Karling, 1978) comb. n.

(Fig. 5–6)

Known distribution. St. George, Tobacco Bay, Bermuda (Type Locality) (Karling 1978) .

New records and material. Observations on live specimens, whole mounted afterwards. Two whole mounts from Las Sardinas (19°56’24”N; 76°46’41”W), Guamá, Santiago de Cuba, Cuba (June 22, 2017), on the alga Dictyota menstrualis with some sand, 0.5 m deep, salinity 35 ‰ (HU XIII.3.20– XIII.3.21). Two whole mounts from Siboney (19°57’34”N; 75°42’07”W), Santiago de Cuba, Cuba (March 22, 2017), intertidal, sand with organic matter, salinity 35 ‰ (HU XIII.3.22– XIII.3.23). Eight whole mounts from Bueycabón (19°57’38”N; 76°57’28”W), Santiago de Cuba, Cuba (February 6 & 21, 2018), fine-grained sand rich in organic matter, 0.5 m deep, salinity 33 ‰ (HU XIII.3.24– XIII.3.31). Two whole mounts from Punta Culebra (8°54’57”N; 79°31’50”W), Panama (December 13, 2011), intertidal, coarse to fine sand collected in front of the Smithsonian Tropical Research Institution (USNM 1642503–1642504) . One whole mount (USNM 1642505) from Bahía Can Can (09°32’23”N; 79°40’31”W), near Portobello, Panama (March 3, 2016), intertidal, very coarse sand. One whole mount from a beach at Araça Bay (23°48’47”S; 45°24’31”W), São Sebastião, São Paulo, Brazil (October 26, 2012), intertidal (HU XIII.3.32) .

Remarks. According to Karling (1978), R. ruffinjonesi comb. n. is characterised by a cirrus with small sclerotised dots, a curved row of scale-like spines (15 μm maximum length), and two distal hooks (72 μm and 45 μm long, respectively). In addition, Karling (1978) describes a “small, easily overlooked spiny diverticulum” in the cirrus. Our re-examination of the holotype of R. ruffinjonesi comb. n. (Fig. 6A–B) reveals that the “small sclerotised dots” of the cirrus described by Karling (1978) are in fact triangular spines of 1–2 μm long (x̄ = 2 μm; n = 20). These spines are larger in the “spiny diverticulum” (4 μm; n = 9). The curved belt described by Karling (1978), consists of a proximal part of large and scale-like spines, followed by a middle part of small spines, and a distal part of strong, more or less triangular spines. In the holotype, the spines in the proximal part of the row (Fig. 6A: cps) are 6–9 μm long (x̄ = 8 μm; n = 15), smaller toward the distal end. The spines of the middle part are 1–2-μm-long (x̄ = 2 μm; n = 10). In the distal part of the belt (Fig. 6A: cds), the spines are 4–20 μm long (x̄ = 13 μm; n = 20), the most distal ones of which are curved (Fig. 6B: ds) and 13–21 μm long (x̄ = 18 μm; n = 5).

In the specimens from Cuba (Fig. 5A–C & 6C–D), the copulatory bulb is 162–220 μm long (x̄ = 192 μm; n = 6). The cirrus (Fig. 6C: ci) is armed with triangular spines of 1–2 μm long (x̄ = 2 μm; n = 27). The spiny belt is 149–247 μm long (x̄ = 176 μm; n = 10). In the proximal part of the belt (Fig. 6C: cps), the spines are 5–9 μm long (x̄ = 7 μm; n = 31), with the size of the spines decreasing distally. In the middle part, the spines are 2–3-μm-long (x̄ = 3 μm; n = 25). In the distal part (Fig. 6C: cds), the spines are 6–18 μm long (x̄ = 12 μm; n = 26), the most distal ones of which (Fig. 5C, 6C–D: ds) are 6–15 μm long (x̄ = 12 μm; n = 9). The distal sclerotised hooks differ in size. The larger hook (Fig. 5A, 6C–D: h1) is 46–60 μm long (x̄ = 54 μm; n = 10) and 15–27 μm wide at its base (x̄ = 21 μm; n = 10). The smaller hook (Fig. 5B, 6C–D: h2) is 21–32 μm long (x̄ = 27 μm; n = 10) and 11–21 μm wide at its base (x̄ = 17 μm; n = 10).

In the specimens from Punta Culebra (Panama) (Fig. 5D–F, 6E) the copulatory bulb is 339–348 μm long (x̄ = 344 μm; n = 2). The cirrus is armed with 2–3-μm-long triangular spines (x̄ = 3 μm; n = 20). The belt of spines is 253–366 μm long (x̄ = 260 μm; n = 2), with spines of 3–13 μm long (x̄ = 8 μm; n = 26) in the proximal part and of 9–23-μm-long (x̄ = 17 μm; n = 16) in the distal part. The most distal spines of the posterior part (Fig. 5F) are 20–21 μm long (x̄ = 21 μm; n = 3) and shark-tooth shaped, with a broad base, curved, and ending in a sharp tip. The larger distal hook (Fig. 5D & 6E) is 62 μm long (n = 2) and 33–34 μm wide at its base (n = 2). The smaller hook (Fig. 5E) is 26–33 μm long (x̄ = 30 μm; n = 2) and 15–16 μm wide at its base (n = 2).

In the specimen from Brazil (Fig. 5G–I, 6F) the copulatory bulb is 165 μm long. No triangular spines were observed in the cirrus. The spiny belt is 165 μm long, with spines of 3–6 μm in length (x̄ = 5 μm; n = 14) in the proximal part and a of 3–15 μm in length (x̄ = 9 μm; n = 14) in the distal part. The most distal spines (Fig. 5I, 6F: ds) of the distal part are shark-tooth shaped, with a broad base and a sharp curved tip, 15–20 μm long (x̄ = 18 μm; n = 3). The larger of the distal hooks (Fig. 5G, 6F: h1) is 60 μm long and 22 μm wide at its base. The smaller hook (Fig. 5H, 6F: h2) is 33 μm long and 16 μm wide at its base.

The specimen from Bahía Can Can (Panama) (Fig. 5J–K) has a copulatory bulb of 310 μm long. The cirrus is armed with 2–3-μm-long triangular spines (x̄ = 2 μm; n = 20). The belt of spines is 251 μm long, with spines of 4–10 μm in length (x̄ = 7 μm; n = 15) in the proximal part and of 2–18 μm in length (x̄ = 10 μm; n = 27) in the distal part. The most distal spines of the distal part are triangular and curved, 16–24 μm long (x̄ = 18 μm; n = 4). The larger of the distal hooks (Fig. 5J) is 56 μm long and 30 μm wide at its base. The smaller hook (Fig. 5K) is 29 μm long and 20 μm wide at its base, slightly curved, ending in a rounded tip.