Species Card of Copepod
Calanoida ( Order )
    Clausocalanoidea ( Superfamily )
        Scolecitrichidae ( Family )
            Amallothrix ( Genus )
Amallothrix pseudoarcuata  (Park, 1970)   (F)
Syn.: Amallothrix arcuata : Sewell, 1947 (p.155, figs.F);
Scolecithricella arcuata: Tanaka, 1962 (p.76, figs.F,M);
Scolecithricella pseudoarcuata Park, 1970 (p.476, 511, Descr.F, figs.F); Roe, 1972 (p.277, tabl.1, tabl.2); Kovalev & Shmeleva, 1982 (p.84); Vives, 1982 (p.292); Lozano Soldevilla & al., 1988 (p.59); Suarez-Morales & Gasca, 1998 a (p.111); Hernandez-Trujillo & Esqueda-Escargera, 2002 (in Appendix)
Ref.:
Bradford, 1973 (p.143); Bradford & al., 1983 (p.78, Rem.); Vyshkvartzeva, 1999 (2000) (p.235); Vives & Shmeleva, 2007 (p.702, figs.F,M, Rem.); Vives & Shmeleva, 2007 (p.738, figs.F, Rem.)
Species Amallothrix pseudoarcuata - Plate 1 of morphological figuresissued from : O. Tanaka in Publ. Seto Mar. Biol. Lab., 1962, X (1). [p.77, Fig.145]. As Scolecithricella arcuata.
Female (from Sagami and Suruga Bay): a, habitus (dorsal); b, forehead (left lateral side); c, last thoracic segment and urosome (left lateral side); d, rostrum (dorsal view); e, P1; f, P2; g, P3, h, P5.

Male (from Sagami Bay): i, forehead (left lateral side); j, last thoracic segment and urosome (left lateral side); k, right P5; l, exopod and endopod of left P5.

Nota Female:
- Cephalothorax about 3.55 times the abdomen length.
- Head and 1st thoracic segment fused, 4th and 5th pedigers incompletely fused, line of fusion observed from the dorsal.
- Posterolateral corners of the last thoracic segment rounded, but slightly produced on posterior margin.
- Caudal rami as long as wide.
- Abdominal segments and caudal rami in the proportional lengths 40 : 20 : 17 : 8 : 15 = 100.
- Abdominal segments 1-3 fringed with fine teeth on distal margin.
- A1 23-segmented on left side, extend to the end of the 3rd abdominal segment.
- A2 exopod 1.3 times as long as endopod.
- Mx1 with 9 setae on the outer lobe; 9 setae on exopod; 8 setae on endopod; 5 setae on the 2nd basal segment; 4 setae on the 3rd inner lobe; 2 setae on the 2nd lobe.
- Mx2 and Mxp as those of Scolecithricella propinqua Sars (1920c) = Amallothrix propinqua (Sars, 1925) = Scolecithrix propinqua (Sars, 1924).
- P1 with an outer edge spine on the 1st exopodal segment.
- P2 with the outer edge spine on the 1st exopodal segment, long and curved, furnished with minute teeth on the inner margin. Terminal spine of exopod with 27 teeth.
- P3 with the outer edge spine of the 1st as in P2.Terminal spine of exopod with 22 teeth.Basis furnished with 2 rows of spinules on the anterior distal border.
- P4 with an short and straight inner marginal seta on the basis; terminal spine of exopod with about 51 teeth.
- P5 2-segmented; terminal segment with a strong inner marginal spine on the distal 1/3 of the inner margin; spine furnished with 2 rows of denticles along anterior margin. Terminal spine about 1/3 the length of the inner marginal spine , and finely serrated on the anterior margin. Outer marginal spine short, and arises somewhat obliquely to the inner marginal spine.

Nota Male:
- Cephalothorax about 2.34 times the length of abdomen.
- Forehead slightly produced.
- Posterolateral corners of the last thoracic segment rounded, slightly produced on the ventro-lateral margin.
- Rostrum as in female.
- Urosome 5-segmented; abdominal segments and caudal rami in the proportional lengths 12 : 33 : 20 : 21 : 4 : 10 = 100.
- Caudal rami a little longer than wide.
- A1 19-segmented on the right, extends to the middle of the 2nd abdominal segment.
- P2 with the outer edge spine of the 1st exopodal segment long and curved and furnished with fine teeth along the inner margin.
- P3 with a long outer edge spine on the 1st exopodal segment, but the spine devoid of fine teeth on the inner margin.
- P5 reaches back to the middle of the 4th abdominal segment. Endopod on right leg moderately long. Exopod of the left leg longer than endopod; the inner margin of the 1st endopodal segment produced triangularly at the proximal 1/3 of the segment.


Species Amallothrix pseudoarcuata - Plate 2 of morphological figuresIssued from : T. S. Park in Bull. Mar. Sc., 1970, 20 (2). [p.510, Figs.175-183]. As Scolecithricella pseudoarcuata.
Female: 175, habitus (dorsal); 176, idem (lateral right side); 177, posterior part of metasome (lateral right side); 178, rostrum (frontal view); 179, A2; 180, Md; 181, Mx1; 182, Mx2 (distal part); 183, Mxp.
Nota: Basis of Md with a long and a minute seta. Mx1: 1st to 3rd inner lobes with 12, 2, and 4 setae, respectively; basis with 5 setae; endopod with 3+5 setae; exopod and outer lobe each with 9 setae.


Species Amallothrix pseudoarcuata - Plate 3 of morphological figuresIssued from : T. S. Park in Bull. Mar. Sc., 1970, 20 (2). [p.512, Figs.184-187]. As Scolecithricella pseudoarcuata.
Female: 184, P1 (anterior); 185, P2 (posterior); 186, P3 (posterior); 187, P5.


Species Amallothrix pseudoarcuata - Plate 4 of morphological figuresissued from : O. Tanaka in Publ. Seto Mar. Biol. Lab., 1962, X (1). [p.76]. As Scolecithricella arcuata.
Female: Proportional lengths of segments A1 on the left side.

Nota:

- A1 23-segmented on the left side; 22-segmented on the right side.


Species Amallothrix pseudoarcuata - Plate 5 of morphological figuresissued from : O. Tanaka in Publ. Seto Mar. Biol. Lab., 1962, X (1). [p.78]. As Scolecithricella arcuata.
Male: Proportional lengths of segments A1 on the right side.
Nota: A1 19-segmented on the right side; 1st segment furnished with a transverse row of hairs on the distal border. Proximal segments each provided with well-developed aesthetascs. Segments 13 and 14 separated.. Segments 14 and 15 make obtuse angle.

NZ: 5

Distribution map of Amallothrix pseudoarcuata by geographical zones
Loc:
G. of Mexico, Canary Is., E Medit., Arabian Sea, Japan
N: 3
Lg.:
(11) F: 2,5; (88) F: 2,44; (117) F: 2,49; (199) F: 2,74-2,66; M: 3,34-3,19; {F: 2,44-2,74}
Rem.: bathypelagic.
For Park (1970) the present female is identical with those described as Scolecithricella arcuata by Sewell (1947) and Tanaka (1962), but different from that described by Sars (1925). According to Sars S. arcuata has swimming legs similar to those of S. lobata, which are quite different from those described here. A new name is therefore proposed for the present female.
Roe (1972) gives dimensions of an undescribed male for this species.
? Cf. Amallothrix arcuata: synonymy pssible (See: Rem . in Amallothrix arcuata.
Last update : 16/03/2017
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