9. THE CLASS CRUSTACEA
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side ; maxilliped knoblike, behind base of second maxilla ; first four
legs biramous, each ramus of three segments which are fringed with
spines on outer margin; each basipodite of two indistinct segments
and with a seta and a row of two to five minute spines on outer side and
a seta on inner side, spines also occur along posteroventral margin
between bases of both rami ; basipodite of first leg with a stout pectinate
spine and a group of smaller simple spines at its posteromedial corner ;
fifth leg uniramous, of two podomeres, basal podomere with one seta
at dorsal distal terminal, terminal podomere about twice as long as
broad, with marginal setae a t distal portion, a row of four to ten
setae on inner margin, and a few oblique rows of spines on ventral
surface.
Male unknown.
13. Pseudomyicola gbbra Pearse, 1947. (Figs. 208 and 209)
(Order Cyclopoida ; family Pseudomyicolidae)
This species was described by Pearse (1947) based on male and
female specimens removed from the gills and mantle cavities of Modiolus demissus, Crassostrea virginica, Atrina rigida, Aequipecten irradians,
Noetia ponderosa and Mytilus edulis collected at Beaufort, North Carolina. In following Humes and Cressey (1958), it is being assigned to the
family Pseudomyicolidae.
Adult female (Pig. 208) 2.23 mm in total length,
0.53 mm wide; head separate from first thoracic segment; second
through fifth thoracic segments become narrower posteriorly, urosome
half as long as metasome ; caudal rami more than twice as long as anal
segment, slender, tapering, with two short terminal setae and two on the
lateral and dorsal surfaces ; genital segment with five little ridges on
sides near posterior margin ; anal segment with minute spinules around
posterior margin ; first antenna with sharp strong spine projecting
posteriorly from basal segment, entire ant,enna of six segments, the
basal being the longest and the basal three being wider than distal
three ; second antenna with basal segment widest, second segment
shortest, and third segment longest, narrowest, and recurved, strong
terminal claw present; swimming legs all biramous with each ramus
being three-segmented ; fifth leg of two podomeres, broad, flat, and
thickened along one margin, with four distal setae, two rows of seven
and eight denticles along middle of thin margin, and eleven spines
across anterior surface ; egg strings, each measuring 0.33-0.55 mm long,
contain five to twelve eggs arranged in linear groups.
Adult male (Fig. 209) similar to female but smaller; total length
1-78 mm, width 0.47 mm; fifth legs relatively smaller, about half as
long as those of female, of two podomeres and with five denticles on
Description.
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side ; maxilliped knoblike, behind base of second maxilla ; first four
legs biramous, each ramus of three segments which are fringed with
spines on outer margin; each basipodite of two indistinct segments
and with a seta and a row of two to five minute spines on outer side and
a seta on inner side, spines also occur along posteroventral margin
between bases of both rami ; basipodite of first leg with a stout pectinate
spine and a group of smaller simple spines at its posteromedial corner ;
fifth leg uniramous, of two podomeres, basal podomere with one seta
at dorsal distal terminal, terminal podomere about twice as long as
broad, with marginal setae a t distal portion, a row of four to ten
setae on inner margin, and a few oblique rows of spines on ventral
surface.
Male unknown.
13. Pseudomyicola gbbra Pearse, 1947. (Figs. 208 and 209)
(Order Cyclopoida ; family Pseudomyicolidae)
This species was described by Pearse (1947) based on male and
female specimens removed from the gills and mantle cavities of Modiolus demissus, Crassostrea virginica, Atrina rigida, Aequipecten irradians,
Noetia ponderosa and Mytilus edulis collected at Beaufort, North Carolina. In following Humes and Cressey (1958), it is being assigned to the
family Pseudomyicolidae.
Adult female (Pig. 208) 2.23 mm in total length,
0.53 mm wide; head separate from first thoracic segment; second
through fifth thoracic segments become narrower posteriorly, urosome
half as long as metasome ; caudal rami more than twice as long as anal
segment, slender, tapering, with two short terminal setae and two on the
lateral and dorsal surfaces ; genital segment with five little ridges on
sides near posterior margin ; anal segment with minute spinules around
posterior margin ; first antenna with sharp strong spine projecting
posteriorly from basal segment, entire ant,enna of six segments, the
basal being the longest and the basal three being wider than distal
three ; second antenna with basal segment widest, second segment
shortest, and third segment longest, narrowest, and recurved, strong
terminal claw present; swimming legs all biramous with each ramus
being three-segmented ; fifth leg of two podomeres, broad, flat, and
thickened along one margin, with four distal setae, two rows of seven
and eight denticles along middle of thin margin, and eleven spines
across anterior surface ; egg strings, each measuring 0.33-0.55 mm long,
contain five to twelve eggs arranged in linear groups.
Adult male (Fig. 209) similar to female but smaller; total length
1-78 mm, width 0.47 mm; fifth legs relatively smaller, about half as
long as those of female, of two podomeres and with five denticles on
Description.