Batheuchaeta Brodsky, 1950
Taxonomic description:
Female. Total length 4.10-5.20 mm. Body elongate-oval. Abdomen 4.0-4.5 times shorter than cephalothorax. Cephalon and Th1 unclearly separated, Th4-Th5 fused. Crest absent. Rostrum absent, or rarely present, vestigial. Posterior Th5 corners rounded or transformed into asymmetrical lobes of variable length and size. Genital segment asymmetrical or symmetrical. Genital field symmetrical or not with "spectacle"-like structure, typical of Batheuchaeta. Abd1-Abd3 with small denticles along posterior border. A1 reach Abd2, may overreach body length by 2-3 distal segments, 24-segmented. Re A2 1.2 times longer Ri, setation of A2: coxopodite with 1 seta, basipodite and Ri1 with 2 setae each, Ri2 with 14 (7+7), rarely 15 setae, Re1 lacking setae, Re2 with 1 distal seta. Setation of all other segments typical of Aetideidae. Md palp base with 3 setae, Ri1 Md with 2-3 and Ri2 Md 10 (9+1) setae, Re typical of Aetideidae. Mx1 gnathobase with 9 terminal and at posterior surface 4 thin setae, second internal lobe with 5, third with 4 setae, 5 setae at protopodite near Ri base, Ri with 14-16, Re with 11 and external lobe with 9 setae. Mx2 typical of Aetideidae: fourth-fifth endites with thickened claw-like setae. Mxp protopodite 1.5-2.0 times longer than Ri Mxp and supplied with 1 long seta proximally, and with 2, 3 and 3 setae and little conical (probably sensitive) appendage (from proximal to distal). P1 with one-segmented Ri, P2 with 3-segmented Ri, other rami of swimming legs 3-segmented. Separation between Re1-Re2 P2 unclear, but all Re segments supplied with external spines. Re2 and sometimes Re1 P2-P4 with row of small denticles near the base of external spine at anterior surface. Posterior surface of Ri2 P2 and Ri2-Ri3 P3-P4 covered with small spines; near distal edge of Ri2 P3-P4 there is a row of denticles.
Male. Total length 4.00-4.50 mm. Body elongate-oval. Rostrum present, small, conic, bifid at the apex. Cephalon and Th1, as well as Th4-Th5 fused. Posterior Th5 corners rounded or with small protuberances. A1 24-segmented. Oral part setation in comparison with that in females reduced. Segmentation of P1-P4 as in females. Re1-Re2, or only Re2 P2 with row of denticles arranged on the anterior surface near the base of external spine of Re2-Re3 or Re3; Re2 P3-P4 with the same row of denticles. P5 strong, of complex structure, large, longer than abdomen, with powerful left basipodite supplied with 2 knobs near internal border. Ri P5 1-segmented, right clavate, configuration of left strongly varies. Re P5 right 2-3 -segmented, left 3-segmented, its Re3 bilobated, or there is an appendage near its base.
Type species: Batheuchaeta lamellata Brodsky, 1950, by original designation.
Remarks. Batheuchaeta enormis Grice and Hulsemann, 1968 removed from Batheuchaeta (Von Vaupel Klein, 1984).
The genus Batheuchaeta includes 8 species.
Batheuchaeta anomala Markhaseva, 1981
Batheuchaeta antarctica Markhaseva, 1986 (male unknown)
Batheuchaeta gurjanovae (Brodsky, 1955)
Batheuchaeta heptneri Markhaseva, 1981 (male unknown)
Batheuchaeta lamellata Brodsky, 1950
Batheuchaeta peculiaris Markhaseva, 1983
Batheuchaeta pubescens Markhaseva, 1986 (male unknown)
Batheuchaeta tuberculata Markhaseva, 1986 (male unknown)