Genus Parisotoma Bagnall.
Two new species of this genus recently have been found in New Zealand—one a mountain-dwelling form, the other a coastal form. These, with the species previously reported, make five in all known from this country. The following key will assist in their separation:—
|1. Ocelli present.||2|
|2. Ocelli six to each side.||3|
|Ocelli four to each side, claw without any teeth; mucro tridentate.||P. notabilis Schaeffer.|
|3. Claw without any teeth, Postantennal organ four times as long as ocellus.||P. sindentata sp. nov.|
|Claw with outer teeth but no inner teeth. Postantennal organ smaller.||4|
|4. Mucro with three teeth.||P. pritchardi
|Mucro with five teeth.||P. quinquedentata
|5. Postantennal organ present, large and elliptical, claw without any teeth, mucro tridentate.||P. linnaniemia
Parisotoma sindentata sp. nov. Plate 41, figs. 35–39.
Colour: In life bluish-black with creamy-white intersegmental bands. Mounted the ground colour is creamy-white overlaid with coarse granular pigment, giving the appearance of a bluish-black insect with broad cream intersegmental bands. Ant. I, II and III deep blue-black with the joints marked by narrow bands of cream. Ant. IV pale-blue. Legs and furcula pale-cream with patches of granular pigment.
Clothing: Well clothed with short plain setae and occasional longer stiff setae. No ciliated setae occur.
Body: Length up to 1.5 mm. Antennae about twice as long as the head, the four segments related as 5:8:10:14. Ant. IV apically with small pit containing sense rod and with large exsertile sensory knob; just below the apex a smaller exsertile sensory knob. Ocelli six to each side, the anterior two slightly larger than the remainder. The ocelli are very difficult to determine, as they are set amongst an irregularly defined field of confused, coarse black pigment granules. Postantennal organ very large, oval, double outlined and about four times as long as the anterior ocellus. Ventral tube short and fat. Abd. III almost equal to Abd. IV.
Legs: Claw without any teeth. Empodial appendage about one-half as long as claw, with broad semi-circular inner lamella reaching to two-thirds its length and narrower outer lamella reaching to tip. No tenent hairs.
Furcula: Mucrodens almost three times as long as manubrium. Mucro elongate and tridentate, there being a large apical tooth, a slightly smaller central conical tooth, and a large lateral basal tooth.
Locality: Lyall Bay, Wellington, from kelp lying on beaches among the rocks. Readily obtained by submerging the kelp in rock-pools, when the Collembola come out and jump about on the surface of the water.
Type: Slide 3/1127, Dominion Museum Collection.
Parisotoma quinquedendata sp. nov. Plate 41, figs. 40–43.
Colour: In life a pale greyish-blue. Mounted, ochreous ground colour with coarse granular bluish-grey pigment all over. First two antennal segments deep blue, last two pale bluish-grey. Ocellar fields black.
Clothing: Heavily clothed with plain setae and numerous long, strongly ciliated setae, which occur at random anywhere on the body or appendages.
Body: Length up to 1.9 mm., twice as long as the head. The four segments related 6:7:11:11. Ant. IV flattened towards the tip and bearing a sensory pit or groove protected by a fringe of curved sense rods. Apically, Ant. IV is rounded and bears one or
two exsertile sensory knobs. Six equal ocelli to each side. Post-antennal organ pear-shaped, double outlined and equal in size to, or slightly larger than, an ocellus. Abd. III slightly longer than Abd. IV as 16: 14. Ventral tube short and slender.
Legs: Claw with a pair of large outer teeth a little above half-way down outer edge. No inner teeth. Empodial appendage half as long as claw, with broad inner and outer lamellae; the inner lamella truncate on distal half and with a small blunt tooth at the angle. Tenent hairs absent.
Furcula: Mucrodens about two-and-a-quarter times as long as the manubrium. Mucro long with five teeth—an apical and a pre-apical of equal height, a smaller basal tooth at one-third from base, flanked on each side by a strong lateral tooth. One lateral tooth is slightly forward of the other.
Locality: Mount Hector, Tararua Range, 2300 ft. under moss. (Coll. by R. Forster.)
Type: Slide 3/1126, Dominion Museum Collection.