Description

Female only (figs. 1-13).

Overall length, excluding egg strings, 3.74 mm-4.46 mm.

Head a little wider than long (0.48 mm-0.52 mm), narrowing to half this width anteriorly, anterior margin rounded, with a small median rostrum; posterolateral angles of head expanded into broad, bilobate processes. First and second antennae carried near anterior margin, mouthtube and remaining cephalic appendages reduced in size, and carried one-quarter distance from anterior margin.

Neck very long and narrow (2.24 mm-3.05 mm × 0.17 mm-0.25 mm), narrowest anteriorly (0.10 mm-0.15 mm) very gradually becoming wider near the trunk.

Trunk width two-thirds length (0.78 mm-1.14 mm × 0.54 mm-0.72 mm), widest posteriorly, narrowing rapidly to fuse with neck over anterior third, with a further slight narrowing at the midpoint; posterior angles broadly rounded, posterior margin with dorsal and ventral swellings over median third, so that in posterior view the trunk is almost +-shaped, the branches short and rounded.

Genital segment small, as wide as long (0.09 mm-0.11 mm × 0.09 mm-0.12 mm), the lateral margins broadly rounded, the egg strings arising ventrolaterally about half way along the segment.

Abdomen as wide as long (0.06 mm-0.07 mm × 0.06 mm-0.08 mm), widest anteriorly, narrowing to two-thirds this width posteriorly, posterior angles rounded; on ventral surface of segment there is a transverse row of very short spines one-third distance from anterior margin, a further row with a median discontinuity two-thirds distance from this margin, and a further transverse row at the base of each caudal lamella.

Caudal lamella carried postero-ventrally on the posterior angles of the abdomen, a little longer than wide (0.020 mm × 0.014 mm), angles rounded, with two setae carried on posterior margin.

Egg strings club shaped, width one-quarter length (1.12 mm-1.33 mm × 0.25 mm-0.31 mm), the eggs multiserriate.

First antenna of five subcylindrical segments, ratios of length from the most proximal 6:4:3:3:2; first segment with eleven setae mostly in the outer distal area; second segment with six setae near outer margin; third segment with five setae, two on outer distal angle, one on outer margin, two on distal margin near inner distal angle; fourth segment with three setae, two on outer distal angle, one on inner distal angle; fifth segment rounded distally, with five setae on distal margin.

Second antenna of three segments; first segment a solid base, as long as wide, with a small spine near outer distal angle; second segment as long as wide, somewhat rounded distally, with a stout blunt spine, one-quarter length of segment, medially on inner margin; third segment as long as second, width two-thirds length, narrowing distally to a blunt point, curved medially, forming a claw which closes against the second segment.

Labrum a scale-like structure 0.06 mm in length, width one-third length, situated immediately anterolateral to mouthtube.

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Mandible 0.027 mm in length, situated on a small wide base, basal width of mandible one-third length, narrowing slightly immediately distal to base, then widening but narrowing again over distal sixth to form a blunt point, a series of small transverse striations over distal half, a branch, one-quarter length of mandible, arising from midpoint, with a row of fine spines on its outer margin, a further jointed branch (palp?) arises near base, length three-fifths mandible length, pointed distally, with transverse striations over distal two-thirds of inner margin.

Mouthtube 0.045 mm in length, subcylindrical, somewhat rounded distally.

Maxilla (?) a lobate structure situated immediately posterior to mandible, two-thirds mandible length, with two setae on rounded distal margin.

Maxilliped (?) 0.039 mm in length, three-segmented, second segment as long as first, third segment half as long again, first segment a broad base; second segment basal width twice length, narrowing to half this width distally; third segment basal width two-thirds length, rounded distally, its distal margin covered by a clump of what appear to be stout spines which are rounded distally.

First pereiopod biramous, each ramus of three segments; protopodite width one-quarter length, rounded distally, median two-thirds of outer margin swollen ventrally, the swelling with a few transverse striations; exopod second segment half length of first, as long as third; first segment with plumose setae on outer distal angle and inner distal angle, third segment with six setae on distal margin; endopod second segment two-thirds length of first, third segment three-quarters length of second; first segment with a small seta on outer distal angle and a long seta on inner distal angle, second segment with a row of cilia on distal half of outer margin and on rounded outer distal angle, and a seta on inner distal angle, third segment rounded, with a row of fine spines on outer margin, and five setae on distal margin.

Second pereiopod similar in form to first, except that proximal segments of rami are proportionately longer, there is a seta on the inner margin of the second segment of exopod, the setae on the distal segment of exopod are proportionately longer, second segment of endopod has two setae on inner distal angle, and row of spines on outer margin of third segment of endopod are missing.

Third pereiopod similar to second.

Fourth pereiopod biramous, each ramus of one segment; protopodite width three-quarters length, narrowing distally, proximal two-thirds of outer margin swollen ventrally; exopod width two-thirds length, subrectangular, with four setae on distal margin; endopod width half length, subrectangular, with three setae on distal margin.