issued from : O. Tanaka in
Publ. Seto Mar. Biol. Lab., 1962, X (1). [p.59, Fig.138].
Female (from Sagami Bay): a, habitus (dorsal); b, forehead (left lateral side); c, last thoracic segment and urosome (left lateral side); d, rostrum (dorsal view); e, Mx2; f, P1; g, P2; h, endopod of P3; i, P4; j, P5.
- Forehead margin highly arched in dorsal aspect, but evenly rounded viewed from the lateral.
- Posterorlateral corners of the last thoracic segment narrowly rounded.
- Abdomen 4-segmented; proportional lengths abdominal segments and caudal rami 37 : 18 : 15 : 10 : 20 = 100.
- Genital segment slightly swollen ventrally.
- abdominal segments 1 to 3 fringed with fine teeth on distal margin.
- Caudal rami 2 times as long as wide.
- A2 exopod 1.4 times as long as endopod (25 : 18).
- Md with a slender endopod.
- Mx1 with on the outer lobe 7 long and 2 short setae; exopod with 6 setae; endopod with 6 setae; 2nd basal with 5 setae; 3rd inner lobe with 3 setae; 2nd inner lobe with 2 setae; 1st inner lobe (= praecoxal arthrite) with 13 setae.
- Mx2 with 8 long vermiform filaments on endopod.
Mxp 2nd basal segment as long as the endopod; 1st basal segment with a bud-like filament on the anterior margin about the middle of segment.
- P1 with an outer edge spine on the 1st exopodal segment.
- P5 composed of a free segment attached to the basal, the distal segment with 2 apical spines of which the inner one is longer, the outer marginal spine very small.
Tanaka remarks that the female specimen resembles Scolecithrix auropecten Giesbrecht (= Archeoscolecithrix auropecten) in the structure of P5 female, but differs from it in the structure of A2, and in the number of setae arising from various parts of the Mx1. It is noticiable that the specimen has an outer edge spine on the 1st exopodal segment of P1 and cylindrical P5, as are found in the genus Amallothrix Sars.