Pinnotheres pisum (Linnaeus, 1767)

Becker, C. & Türkay, M., 2010, Taxonomy and morphology of European pea crabs (Crustacea: Brachyura: Pinnotheridae), Journal of Natural History 44 (25 - 26), pp. 1555-1575 : 1564-1569

Pinnotheres pisum (Linnaeus, 1767)

( Figure 1A–C, 4A–D , 5A–C )

Cancer pisum Linnaeus, 1767, p 1039 (type probably not extant, type-locality: “Barbarbia, North coast of Africa”); Herbst, 1783, p 95–96, plate 2, figure 21.

Cancer mytilorum albus Herbst, 1783, p 101 , plate 2, figure 24.

Pinnotheres pisum: Bosc, 1802, p 243 [new combination]; H. Milne Edwards, 1837, p 31–32, plate 19, figure 1a–f; Atkins, 1926, p 475–493, plate 1–5, text-figures 1–4; Atkins, 1954, p 687–700, figures 1–7, 14, 16; Lebour, 1928, p 109–110, 114–115, plate 2, figures 1–6; Lebour, 1928, p 553 (larval stages) Christensen, 1959, p 267–270, figures 1–2.

A detailed synonymy is represented in Schmitt et al. (1973).

Material examined

Northeast Atlantic. North Sea , Dogger Bank: 13, host: Mactra stultorum, Stat. DOGN-14 Ku, 54°30.73′N, 2°40.352′E – 54°30.478′N, 2°39.246′E, 19 July 2006, beam trawl, RV SENCKENBERG, leg. K. Pietratus ( SMF 34583). 13, 2♀, host: Mactra stultorum, Stat. DOGN-6 Ku , 54°45.489′N, 1°43.853′E – 54°45.7′N, 1°42.443′E, 19 July 2006, beam trawl, RV SENCKENBERG, leg. K. Pietratus ( SMF 34584– SMF 34586). 13, 1♀ juvenile hard stage, host: Spisula solida, Dogger Bank-West, Stat. DOGO-9 RD, 54°59.635′N, 1°39.267′E – 54°59.635′N, 1°39.267′E, 01 August 2008, ring dredge, leg. RV SENCKENBERG, ( SMF 34043). 1♀ juvenile hard stage, host: Mactra stultorum, Dogger Bank-West, Stat. DOGO-4 RD, 54°28.71′N, 1°51.771′E – 54°28.71′N, 1°51.771′E, ring drdge, 30 July 2008, leg. RV SENCKENBERG, ( SMF 34040). 1♀, host: Mactra stultorum, Dogger Bank-West, Stat. DOGO-5 Ku , 54°37.473′N, 1°42.225′E, 54°–37.307′N, 1°42.38′E, beam trawl, 30 July 2008, leg. RV SENCKENBERG ( SMF 34007). 1♀, host: Mactra stultorum, Dogger Bank-East, Stat. DOGO-17 Ku , 54°51.011′N, 2°5.168′E – 54°51.859′N, 2°5.222′E, beam trawl, 1 August 2008, leg. RV SENCKENBERG ( SMF 34008). 13, host: Mactra stultorum, Dogger Bank-East, Stat. DOGO-26 Ku , 54°50.798′N, 2°49.403′E – 54°51.625′N, 2°50.568′E, beam trawl, 1 August 2008, leg. RV SENCKENBERG ( SMF 34009). 1♀ ovigerous, host: Mactra stultorum, Dogger Bank-East , DOGL-14 ku, 54°31′N, 2°40.8′E – 54°30.8′N, 2°38.8′E, beam trawl, 3 August 2004, leg. RV SENCKENBERG ( SMF 34006). 1♀, host: Gari fervensis, Dogger Bank-East, Stat. DOGN-40/8 Ku , 55°27.544′N, 4°8.624′E – 55°27.768′N, 4°6.907′E, beam trawl, 24 July 2006, RV Notes: scale bars, 2 mm (A), 500 µm (B), 250 µm (C).

SENCKENBERG, leg. K. Pietratus ( SMF 32742). 1♀, host: Mactra stultorum, Dogger Bank-East, Stat. DOGO-11 RD, 54°45.396′N, 2°0.459′E – 54°45.396′N, 2°0.459′E, 1 August 2008, leg. RV SENCKENBERG ( SMF 34041). 1♀ juvenile hard stage, free-living, Dogger Bank-East, Stat. DOGO-29 Ku, 55°8.026′N – 55°8.323′N, 2°41.64′E – 2°43.195′E, 3 August 2008, leg. RV SENCKENBERG ( SMF 34042). 13, 1♀ ovigerous, host: Mactra stultorum, Dogger Bank-East, Stat. DOGO-40/1 RD, 55°27.453′N, 4°8.622′E – 55°27.453′N, 4°8.622′E, 4 August 2008, leg. RV SENCKEN- BERG ( SMF 34044). 1♀ juvenile hard stage, host: Donax vittatus, Dogger Bank-East, Stat. DOGO-13a RD, 54°27.113′N, 2°16.064′E – 54°27.113′N, 2°16.064′E, 30 July 2008, leg. RV SENCKENBERG ( SMF 34045). 1♀ ovigerous, host: Gari fervensis, Dogger Bank-East, Stat. DOGO-40/1 Ku, 55°27.612′N, 4°8.219′E – 55°27.525′N, 4°10.267′E, 4 August 2008, leg. RV SENCKENBERG ( SMF 34046). 1♀ ovigerous ,

Notes: scale bars, 2 mm (A), 1 mm (B), 500 µm (C).

host: Mactra stultorum, Dogger Bank-East, Stat. DOGM-14 Ku, 54°31.008′N, 2°40.609′E – 54°30.847′N, 2°40.535′E, hard-bottom dredge, 3 August 2005, RV SENCKENBERG, leg. M. Türkay ( SMF 34374) .

North Sea , German Bight: 783, 239♀ stage I to stage V (in part ovigerous) , host: Modiolus modiolus , Helgoland Trench , 54°08.419′N – 54°08.599′N to 07°50.921′E – 07°53.431′E, beam trawl/hard bottom dredge, January–December 1985 –1992, leg. RV SENCKENBERG, uncatalogued material. 1♀, Helgoland Trench , Stat. NR-45 Ku, 54°8.56′N, 7°52.3′E – 54°8.52′N, 7°52.08′E, beam trawl, 13 August 1984, leg. RV SENCKENBERG ( SMF 12887). 23 free living, Stat. D 2007-27 Ku , 55°17.046′N, 6°43.88′E – 55°17.55′N, 6°45.238′E, beam trawl, 7 August 2007, RV SENCKEN- BERG , leg. K. Pietratus ( SMF 32743). 1♀, 13, host: Spisula solida, Loreley Bank , ring dredge, 14.05.1985, leg. RV SENCKENBERG, uncatalogued material. 1♀ ovigerous, host: Mactra stultorum , north of Juist , Stat. D 2007-3 RD, 53°47.161′N, 7°3.225′E – 53°47.161′N, 7°3.225′E, hard bottom dredge, 1 August 2007, RV SENCK- ENBERG, leg. M. Türkay ( SMF 34375). 1♀, ovigerous, host: Spisula elliptica, Wangerooge, Stat. LR-060728-2 Ku , 53°49.395′N, 7°52.498′E – 53°48.899′N, 7°53.863′E, 28 July 2006, beam trawl, RV SENCKENBERG, leg. K. Pietratus ( SMF 34587). 1♀, Norderney , Stat. V53-078 Ku , 53°49.51′N, 7°13.64′E – 53°49.72′N, 7°12.13′E, beam trawl, 18 February 1987, RV Valdivia ( SMF 32676). 13, 1♀, host: Mactra stultorum, Jadebusen, Stat. WH 287 Stat. 398, 1 May 2006, beam trawl, RV WALTER HERWIG, leg. K. Pietratus ( SMF 32741) .

North Sea , other locations: 13, host: Mytilus edulis , Netherlands, close to the German boarder, mussels from a restaurant, 15 September 2006, leg. C. Becker, SMF 34582 . 33, 1♀, host: Mytilus edulis , North Sea , Ireland, supermarket “Metro” in Frankfurt, Germany, 2005, leg. S. George ( SMF 32744) .

France, Brittany: 1♀, host: Mytilus edulis, Roscoff , 1 April 1990 – 31 May 1991, leg. J. Klein ( SMF 34382) . 1♀ ovigerous, host: Mytilus galloprovincialis , 48°34′N, 2°24′W, 8 October 1994, leg. C. d’Udekem d’Acoz, SMF 33457. 13, 1♀ juvenile hard stage, host: Spisula solida , Région de Dinard : “Les Haches”, ring dredge, April 1993, leg. C. d’Udekem d’Acoz ( SMF 34001) . 1♀ juvenile, host: Mytilus edulis, Brest (supermarket), April 1991, leg. J. Klein ( SMF 34318) . 1♀, host: Mytilus edulis , France, Brittany, Brest (supermarket), 17 April 1991, leg. J. Klein ( SMF 34319) . 1♀, host: Mytilus edulis , France, Brittany, Vannes (supermarket), 17 April 1991, leg. J. Klein ( SMF 34320) .

France, other locations: 93, 17♀, host: Mytilus edulis , France, Haute-Normandie, 49°19′N, 0°22′W, 8 October 1994, leg. C. d’Udekem d’Acoz, SMF 33456 . 2♀, host: Mytilus edulis from the market hall in Frankfurt/ Germany, origin: France, Bay of Biscay, Oléron , 6 August 2005, leg. C. Becker ( SMF 34576). 23, 11♀, host: Mytilus edulis from the market hall in Frankfurt / Germany, origin: France, Oléron , 17 February 2007, leg. C. Becker ( SMF 34581) .

Mediterranean. Northern Adriatic Sea, Croatia, Istria: 1♀ ovigerous, Rovinj , mole in front of the Institute Ruder Boškovi 0, Stat. Rov 93, 1 September 1993 ( SMF 31503) . 13, 1♀, host: Mytilus galloprovincialis, Rovinj , in front of the old town, leg. 19 August 1989 ( SMF 31519) . 1♀, host: Ostrea edulis, Rovinj, Big Figarola , skin-diving, 1 September 2005, leg. C. Becker and S. Kalscheid ( SMF 34579) . 1♀ ovigerous, host: Mytilus galloprovincialis, Rovinj, Sv. Katarina , 9 July 1986, leg. U. Pettke ( SMF 31512) . 13, 2♀, 1♀ juvenile stage III–IV, 5♀ ovigerous, host: Pinna nobilis, Rovinj , bay of Bale , 1982, leg. U. Pettke ( SMF 33808) . 1♀ ovigerous, host: Pinna nobilis, Rovinj , bay of Bale , July 1982, leg. U. Pettke ( SMF 33810) . 2♀, Rovinj , Sv. Katarina, SE-coast, Stat. Rov 01-02, 45°4.651′N, 13°37.891′E – 45°4.651′N, 13°37.891′E, leg. 13 August 2001 ( SMF 31500) . 13, 1♀, host: Pinna nobilis, Rovinj , bay of Bale , July 1982 ( SMF 31501) . 1♀, 13, host: Pinna nobilis, Rovinj , bay of Bale , July 1982 ( SMF 31502) . 13, 1♀ ovigerous, host: Pinna nobilis, Rovinj , bay of Bale , July 1987, leg. D. Krämer ( SMF 33809) . 83, 3♀, 3♀ juvenile, 5♀ ovigerous, host: Mytilus galloprovincialis, Rovinj, Monte Mulini , leg. 21 August 1989 ( SMF 31517) . 23, 2♀ juvenile, 6♀ ovigerous, Rovinj , Val Salina, leg. 23 August 1989 ( SMF 31518) . 1♀, host: Pinna nobilis, Rovinj , December 2003, leg. D. Brandis ( SMF 34577) . 13, 1♀ ovigerous, host: Pinna nobilis , bay of Kolone , July 1983 ( SMF 31504) . 1♀, host: Ostrea edulis, Limski Fjord , skin-diving, 29 August 2005, leg. C. Becker ( SMF 34580) . 1♀ juvenile stage II, host: Mytilus galloprovincialis, Limski Fjord , 21 August 1989 ( SMF 31520) . 3♀, Limski Fjord , August 1968, leg. Kinzelbach ( SMF 5099 ) .

Tyrrhenian Sea: 1♀, Italy, Isola d’Elba, leg. S. Rau ( SMF 5303 ) .

Ionian Sea : 13, 1♀, host: Pinna nobilis , Greece, Ionian Islands, Island Marathonisi in front of Island Zakynthos, 36°45′13″N, 22°34′25″E, August 1979, leg. B. Kurlemann ( SMF 16285) .

Sea of Marmara: 33, 1♀ ovigerous, host: Pinna nobilis , Turkey, Princes’ Islands , Büyükada, July–August 1966, leg. M. Türkay ( SMF 4451 ) . 23, 1♀ ovigerous, host: Pinna nobilis , Turkey, Princes’ Islands , KInalIada, June 1964, leg. M. Türkay ( SMF 4455 ) . 2♀, host: Pinna nobilis , Turkey, Princes’ Islands , Büyükada, July 1964, leg. M. Türkay ( SMF 4467 ) .

Male

General description ( Figures 1B, 4A ). Colour light, nearly white to ivory with orange ornamentation on dorsal surface of carapace, chelipeds and walking legs. Carapace rounded, dorsally very convex, strongly calcified, not translucent, without defined regions and lateral teeth. Surface plain and smooth owing to lack of setae. Front very pronounced, slightly acuminated in middle. Eyes clearly visible in dorsal view, with light orange colouration in living specimens.

Chelipeds (P1), relative length of articles of walking legs and third maxillipeds consistent with description of female given below, but chelipeds generally much stronger and stouter than in adult females.

Second and third pair of walking legs (P3, P4) with swimming fringes: two rows of long pappose setae on distal articles. One running dorso-posteriorly on carpus and propodus, one ventro-anteriorly. Shorter pappose setae lining dorsal and ventral margins of all walking legs (P2–P5).

Largest males, found in Pinna nobilis , with carapace width of about 7 mm.

Pleon (abdomen) and sternum ( Figure 4B ). Male abdominal segments clearly separated. Belonging to Thoracotremata, male gonopores on sternum. Pleon narrow, general shape triangular. Pleon tapering distally from segment 3 to segment 6, lateral margins of segment 3 slightly rounded, shape of segment 4 and 5 trapezoid, margins of segment 6 slightly rounded, shape of telson trapezoid.

Whole outer margin of pleon setose, remaining surface smooth.

First gonopod ( GP 1) ( Figure 4C, D ). GP 1 straight over almost total length, strongly flattened dorso-ventrally. Distal part narrowed abruptly with light curve in last 7/8. Distal openings of ejaculatory canal oriented slightly towards lateral side of body. Gonopods with long pappose setae on proximal base and along total length, setae more numerous in curve of distal part.

Female (adult)

General description ( Figure 1A, C, 5A ). Colour light ivory, nearly white. Carapace subglobular or slightly wider than long, especially in large females. Carapace very soft, translucent through decalcification, without defined regions and lateral teeth. Eyes hardly visible in dorsal view, especially in large females. Eyes of living specimen with light orange colouration. Carapace and whole body surface smooth, shiny owing to lack of setae. Pleon very broad, rounded, covering whole ventral side including coxae, reaching front anteriorly. Pleons’ margin setose, outer surface smooth.

Maximum body size of adult (ovigerous) females about 18 mm in carapace width in specimen from Pinna nobilis , minimum about 4 mm in small ovigerous females inhabiting Mytilus edulis .

Juvenile females consistent with the description of males (except for pleopods).

Chelipeds and walking legs ( Figure 5A, B ). Cheliped (P1), especially palm, slender in adult females (stouter in juvenile females and males). Cutting edge of claw with one single pointed tooth on movable finger (dactylus) and one single tooth on fixed finger (propodus). Inner and outer surface of palm rather smooth, only scattered setae. Simple and plumose setae located near angle of propodus and dactylus and on cutting edge of claw. Field of long pappo-serrate setae forming dense comb on bottom side of claw.

Walking legs (P2–P5) with short, pointed, curved dactyli. Dactyli of P2–P5 considerably less than half as long as propodus. Dactyli almost of equal length in all walking legs. Swimming fringes of second and third walking legs (P3, P4) present in juvenile females, reduced in adults.

Third maxilliped ( Figure 5C ). Third maxilliped with large completely fused merusischium-article. Dactylus of palp inserting underneath propodus (subterminally). Flagellum two-segmented with tuft of long simple setae originating from tip. Third maxillipeds’ inner margins densely fringed with long simple setae, surfaces of merusischium, carpus and propodus smooth.

Comments

In contrast to data in the literature ( Schmitt et al. 1973), we found Pinnotheres pisum exclusively in bivalves, but never in ascidians.

Figures

Figure 4. Male of Pinnotheres pisum. (A) Dorsal view on male; (B) male pleon; (C) ventral view on left first gonopod; (D) dorsal view on left first gonopod.

Figure 5. Female of Pinnotheres pisum. (A) Dorsal view on female; (B) left cheliped with comb of setae; (C) exterior of left maxilliped.