Deep-Water Crustacea of the Genus Sergestes (Decapoda, Natantia) from Cook Strait, New Zealand
Colour in Life
Colour in Life
The only specimens seen in a fresh condition were the damaged female from Collection 83 and the undamaged female from Collection 100. Each was examined within a few hours of capture and the following colour notes combine the observations made on both:
Entire body and appendages uniform scarlet, eyes black, organs of Pesta absent, numerous intense purple lens-less photophores (fading to yellow in preservative) arranged as follows:
Carapace: An irregular patch present behind base of antennule and above ventrolateral angle, an irregular row in roof of branchial chamber at level of suprabranchial ridge.
Eyestalk: None.
Antennular Peduncle: 2 distoventrally on 3rd segment.
Antennal Peduncle: 1 distolaterally on penultimate segment, 1 distoventrally on ultimate segment.
Scaphocerite: 1 ventrally at articulation and a longitudinal row of about 9–11 irregularly spaced in distal two-thirds. One long streak and 1 small spot diagonally in proximal third.
Mandible: 1 at distal end of proximal segment of palp.
1st Maxilla: None.
2nd Maxilla: 5 on anterior half of exopodite and a large kidney-shaped one on posterior half.
1st Maxilliped: 1 on the penultimate segment of the exopodite.
2nd Maxilliped: 1 proximally on merus, 1 distally on both carpus and propodus.
3rd Maxilliped: 1 distodorsally on both merus and carpus, and 1 distoventrally on propodus.
1st Pereiopod: 1 proximally on ischium, and 2, one larger than the other, proximally on the merus.
2nd Pereiopod: 1 proximally and 1 distally on ischium, none on merus.
3rd Pereiopod: 2 on ischium as in 2nd pereiopod, row of 8–13 on merus.
4th Pereiopod: 2 on ischium as in 2nd pereiopod, 1 distally on merus, and 2 distally on carpus. 2 internal pigmented patches were visible by reflected light, 1 on ischium and 1 proximally on merus; these were found on dissection to be similar in structure to the externally visible photophores.
5th Pereiopod: 2 on ischium as in 2nd pereiopod, 1 distally on both merus and carpus.
page 191st Pleopod: 1 proximally on exopodite.
2nd–5th Pleopods: 2 distolaterally on coxopodite, 1 distally on basipodite, and 1 proximally on exopodite.
Uropod: 1 at proximomedial angle of both endopodite and exopodite, an irregular streak and spot longitudinally on proximal third and an irregularly spaced longitudinal row of about 5 on distal third of exopodite.
Thoracic Sternum: 1 between bases of antennae. 1 large one each side of labrum. 2 between bases of lst-2nd maxillipeds. 1 between bases of 2nd-3rd maxillipeds. 1 between bases of 3rd maxillipeds. 1 between bases of lst-2nd pereiopods. 1 between bases of 2nd-3rd pereiopods. 1 median and 1 pair between bases of 3rd-4th pereiopods. 1 between bases of 4th pereiopods. 1 median and 2 pairs (1 large and 1 small) between bases of 4th and 5th pereiopods. 1 median pair between bases of 5th pereiopods. 1 large one behind base of each 5th pereiopod.
Abdominal Sternum: Each sternite (1st–6th) with one prominent antero-lateral pair and in addition in the midline: 1st sternite, 1 pair behind bases of pleopods. 2nd sternite, 1 pair and 1 unpaired in front of, and 1 pair behind, bases of pleopods. 3rd sternite, 1 pair and 1 unpaired in front of, 1 unpaired between and 1 pair behind, bases of pleopods. 4th sternite, 1 pair in front of, 1 unpaired between, and 1 unpaired behind, bases of pleopods. 5th sternite, 1 unpaired between and 1 unpaired behind, bases of pleopods. 6th sternite, a median longitudinal row of 4–6 irregularly shaped photophores (the posterior one wider than long).