Diplecogaster Fraser-Brunner 1938

• Main Authors: Fricke, Ronald, Wirtz, Peter, Brito, Alberto
• Format: Text
• Language: unknown
• Published: Zenodo 2015
• Subjects: Biodiversity; Taxonomy; Animalia; Chordata; Actinopterygii; Perciformes; Gobiesocidae; Diplecogaster; Diplecogaster ctenocrypta; Diplecogaster euxinica; Diplecogaster melagops; Diplecogaster pectoralis; Diplecogaster tonstricula; Norway; Cornwall; Noire; Briggs; Clowes; Faroes
• Online Access: https://dx.doi.org/10.5281/zenodo.4328111; https://zenodo.org/record/4328111

Diplecogaster Fraser-Brunner 1938 Diplecogaster Fraser-Brunner 1938: 415 (type species: Cyclopterus bimaculatus Bonnaterre 1788 by original designation). Diagnosis Three and one half gills; gill membranes attached to the isthmus; disc double; dorsal and anal fins normal with strong rays; disc length 3.2 – 5.2 in SL; no spine in subopercular area; 4 – 9 dorsal-fin rays; 3 – 8 anal-fin rays; 20 – 26 pectoral-fin rays; premaxillaries short; maxillaries well forward in position; head lateral-line system with two pores in the lacrymal canal. Remarks A total of six valid species is known in this genus; a checklist of the species and an identification key are presented below. Within the genus Diplecogaster , two species groups can be distinguished: – Diplecogaster-bimaculata group: characterised by a moderate number of 4 – 8 rays in the dorsal fin and 3 – 7 in the anal fin ( D.- ctenocrypta group: 9 rays in the dorsal fin, 8 rays in the anal fin), and the position of the anus which is situated in the middle between disc and anal-fin origin ( D.- ctenocrypta group: situated closer to the analfin origin than to the end of the disc). Species. D. bimaculata, D. euxinica, D. megalops, D. pectoralis . Distribution . Mediterranean Sea, Black Sea, eastern Atlantic Ocean, South Africa. – Diplecogaster-ctenocrypta group (reviewed in the present paper): characterised by a high number of 9 rays in the dorsal fin and 8 in the anal fin ( D.- bimaculata group: 4 – 8 rays in the dorsal fin, 3 – 7 rays in the anal fin), and the position of the anus which is situated closer to the anal-fin origin than to the end of the disc ( D.- bimaculata group: situated in the middle between disc and anal-fin origin). The species of the group are further distinguished from the Diplecogaster bimaculata, D. euxinica and D. pectoralis in having 14 – 15 caudalfin rays (18 – 21 in D. bimaculata, D. euxinica and D. pectoralis) , and lacking lateral papillae in disc region A (many lateral papillae present in D. bimaculata, D. euxinica and D. pectoralis ), and from D. megalops in 13 – 16 rakers on third gill arch (7 – 9 rakers in D. megalops ). Species. D. ctenocrypta, D. tonstricula n. sp. Distribution . Eastern Atlantic Ocean. Checklist of the species of Diplecogaster Diplecogaster bimaculata (Bonnaterre [ex Pennant] 1788) Cyclopterus bimaculatus Bonnaterre [ex Pennant] 1788: 29, pl, 86, figure 355 (seas of England; no types known) Lepadogaster ocellatus Risso 1810: 74 (Villefranche-sur-Mer, France; no types known). Lepadogaster reticulatus Risso 1810: 77 (Nice, France; no types known). Lepadogaster mirbeli Risso 1820: 249 (Nice, France; no types known). Lepadogaster desfontanii Risso 1827: 275, pl. 14, figure 39 (Nice, France; syntypes: MZUF 584-0093, 10 specimens). Lepadogaster latirostris Costa 1840: Lepadogaster p. 4 (Naples, Italy; no types known). Lepadogaster urifasciatus Costa 1840: Lepadogaster p. 9 (Gulf of Salerno, Italy; no types known). Lepadogaster norvegicus Düben 1845: 112 (Norway; no types known). Lepadogaster listellus Nardo [ex Chiereghini] 1847: col. 113 (Italy; no types known). Lepadogaster raninus Nardo [ex Chiereghini] 1847: col. 113 (Italy; no types known). Lepidogaster couchii Saville-Kent 1883: 55 – 56 (Devonshire and Cornwall, UK; no types known). Distribution: Mediterranean Sea, north-eastern Atlantic: Norway and Faroes south to Gibraltar. Diplecogaster ctenocrypta Briggs 1955 Diplecogaster ctenocrypta Briggs 1955: 32, figure 85 (Gran Canaria, Canary Islands; holotype: ZMUC P9037). Distribution: Canary Islands. Diplecogaster euxinica Murgoci 1964 Diplecogaster bimaculata euxinica Murgoci 1964: 229, figure 1 (Romania, Black Sea; holotype: MGAB 55). Distribution. Black Sea. Diplecogaster melagops Briggs 1955 Diplecogaster megalops Briggs 1955: 31, figure 84 (off Durban, KwaZulu-Natal, South Africa; holotype: ZMUC P9031). Distribution: South Africa. Diplecogaster pectoralis Briggs 1955 Diplecogaster bimaculata pectoralis Briggs 1955: 30, figure 83 (Gran Canaria, Canary Islands; holotype: ZMUC P9034). Distribution: Canary Islands, Madeira, Azores, Cape Verde Islands. Diplecogaster tonstricula new species (present paper) Distribution: Canary Islands, Senegal. Key to the species of the genus Diplecogaster 1. Dorsal-fin rays 4 – 8; anal-fin rays 3 – 7............................................................................................. 2 - Dorsal-fin rays 9; anal-fin rays 8......................................................................................................... 5 2. Eye large, eye diameter 0.5 – 0.6 in bony interorbital, 2.3 – 3.6 (mean 3.25) in head length; no ocelli on sides of body; South Africa............................ Diplecogaster megalops - Eye relatively small, eye diameter 0.7 – 1.2 in bony interorbital, 3.2 – 4.9 (mean 4.2) in head length; at least one ocellus on side of body below pectoral fin; eastern Atlantic, Mediterranean Sea and Black Sea................................................................................................................. 3 3. Snout length 3.7 – 7.7 in head length; upper attachment of axial, dermal flap opposite pectoral-fin rays 10 – 19 (mean 18); principal caudal rays 12 – 14.................................................................................................................... Diplecogaster euxinica - Snout length 3.3 – 3.8 in head length; upper attachment of axial, dermal flap opposite pectoral-fin rays 10 – 13 (mean 12); principal caudal rays 9 – 12............................................... 4 4. Pectoral-fin rays 21 – 24; caudal – peduncle depth 1.2 – 1.5 (mean 1.3); eye diameter 3.7 – 4.9 (mean 4.1) in head length............................................................................ Diplecogaster bimaculata - Pectoral-fin rays 25 – 26; caudal – peduncle depth 1.0 – 1.2 (mean 1.1); eye diameter 3.2 – 3.9 (mean 3.6) in head length................................................................................ Diplecogaster pectoralis 5. Pelvic disc with lateral papillae in region A; disc region B with 5 rows of papillae; mandibular canal with 1 pore; principal caudal-fin rays 16; interorbital distance 5.4 in head length; distance between disc and anus 19% of SL........................ Diplecogaster ctenocrypta - Pelvic disc without lateral papillae in region A; disc region B with 2 rows of weak papillae; mandibular pores missing; principal caudal-fin rays 14 – 15; interorbital distance 4.1 – 4.6 in head length; distance between disc and anus 14 – 17% of SL................................................................................................... Diplecogaster tonstricula n. sp. : Published as part of Fricke, Ronald, Wirtz, Peter & Brito, Alberto, 2015, Diplecogaster tonstricula, a new species of cleaning clingfish (Teleostei: Gobiesocidae) from the Canary Islands and Senegal, eastern Atlantic Ocean, with a review of the Diplecogaster-ctenocrypta species-group, pp. 731-748 in Journal of Natural History 50 on pages 734-736, DOI: 10.1080/00222933.2015.1079659, http://zenodo.org/record/3989731 : {"references": ["Fraser-Brunner A. 1938. Notes on the classification of certain British fishes. Ann Mag Nat Hist. 2: 410 - 416.", "Bonnaterre JP. 1788. Tableau encyclopedique et methodique des trois regnes de la nature \u2026 Ichthyologie. Paris: Panckoucke; lvi + 215 pp., Pls. A-B + 1 - 100.", "Risso A. 1810. Ichthyologie de Nice, ou histoire naturelle des poissons du departement des Alpes Maritimes. Paris: F. Schoell; xxxvi + 388 pp., pls. 1 - 11.", "Risso A. 1820. Memoire sur quelques poissons observes dans la mer de Nice. 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