An account of the Crustacea of Norway V7-1 Copepoda Supplement

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AN ACCOUNT OF THE CRUSTACEA OF NOR WAY WITH SHORT DESCRIPTIONS AND FIGURES OF ALL THE SPECIES BY G O SARS VOL VII COPEPODA SUPPLEMENT PARTS I & II CALANOIDA, HARPACTICOIDA (part) WITH ;6 AUTOTYPIC PLATES BERGEN PUBLISHED BYTHE BERGEN MUSEUM SOLO BY ALB CAMMERMEYERS'S FORLAG, CHRISTIANIA 1919 INTRODUCTION The considerable number me additional of species observed during the supplementary Volume to the Copepoda, and of these species, and embracing all the containing descriptions figures years has induced latter leading divisions number of treated to publish a of The preceding Volumes the in these species has been derived from the extensive far greater division Har- pacticoida; but also of Calanoida and Cyclopoida several interesting forms are added in Most the present Volume picket up from bottom-samples taken ities on our southern collections of study of the one, and I coast, Copepoda made present order of not doubt extensive coast will reveal Crustacea viz., in of the species here described different times, at Korshavn and the same Crustacea still Riser, localities and some It have been chiefly in local- is also from mixed evident that the remains to be a very promising that continued investigations in other places of our many additional forms worthy of note Calanoida Fam Phaennidae Gen Xanthocalanus, Giesbr Of Remarks this genus, in addition to the species originally recorded by Giesbrecht from the Mediterranean, several new forms have been described in recent time from the northern Ocean, some of them being, however, so nearly related, the ones to the others, that they, without a very close examination, may the of easily be confounded As moreover, owing to the great britlleness appendages, most specimens obtained are more or less defective, the determination of the species belonging to the present genus no small difficulty founded different is connected with have myself formerly, under the name X borealis, conThe one originally described by the present author species I under that name from the Nansen Expedition is a true arctic form, which does Norway It has recently been identified, though The Norwegian with some doubt, by Mr With with X hirtipes Vanhoeffen form recorded in Vol IV of the present work as X borealis is quite certainly not occur not identical inferior size seduced to the off with coast the the arctic this supposed differing, outer to as it does, both by joints in which the appendages be young, not yet the last pair of legs last and the presence changed fully pair the legs, in my much I was material of by the complete fusion apical spines, exhibited a These specimens the arctic form developed females, and that accordingly their character according to age has, however, turned out to be quite wrong adult specimens with of of only in its of the last pair of legs erroneous identification by the occurrence certain resemblance to these I species, and by the rather unlike structure some few specimens, of of I This supposition have subsequently found very same structure of the last pair of legs, fully and I have convinced myself that they are referable to a well defined species, which will be described below For the other Norwegian species I propose the name A 3rd Norwegian species has been described in the present work X fallax The most reliable character for distinguishing the species as X propinqvus of the present genus unquestionably the structure of the is Xanthocalanus minor, (Pi pair of legs last Giesbr I) Xanthocalanus minor, Giesbrecht, Fauna and Flora des Golfes von Neapel: Pelagische Copepoden, Characters Female oblong oval in Specific division anterior Cephalosome nearly behind exhibiting the lateral lobes triangularly the genital length U Fig 32 with slender, moderately the the middle; dorsal face only slightly dorsally a exposed part of the trunk, and transverse suture; distinct Rostral filaments of moderate length anterior and abruptly produced, and extending somewhat beyond the middle Urosome comparatively segment the of anterior division; exceeding short, scarcely segment only genital in slightly protuberant of the succeeding segments combined; anal Caudal rami scarcely longer than they are broad; apical well developed and somewhat divergent, the innermost but one, as usual, and below, about segment very setae the length small considerably longer than the others when tending, and 12, Last trunkal segment completely coalesced with the preceding one; reflexed of Body as long as the middle extremity narrowly rounded Pi form, greatest width not nearly attaining half somewhat behind the length and occurring vaulted 286 (footnote), p to reflexed, end the X fallax oral parts almost exactly as in though having the spinules similar structure, Last pair of in Posterior antennae caudal rami Natatory legs likewise of a very of the inner however, rather unlike those legs, joints being, as in ramus fewer in number the said species, the outer X borealis, completely coalesced to an elongated some- what curved piece armed spines, Anterior antennae rather elongated, exof the at the end with only comparatively edges of the piece nearly smooth, with only a few short, cilia subequal at the outer curvature Body ment at the the living animal highly pellucid, with only a faint rosy pig- in end Length of Remarks his some of the segments of adult female reaching to 2.70 The figure mm given by Giesbrecht of the X minor agrees pretty well with those appendages form, and figures I were think therefore that given by I am Giesbrecht, in last pair of leg in the above-described right in identifying both, though no other nor any description of the species The body is said to be only 1.20 mm.: but I suppose that an exact measurement may have been rendered difficult by the bad condition of the length of the specimen observed by that author As above stated, the present species was formerly confounded by me solitary with X fallax tainly time recorded as X borealis), to which species (at that resemblance bears a close somewhat more slender form of the of anterior antennae, legs, apical spines are these and in the of in the greater length the arctic species, X borealis in In densely hirsute, everywhere the and the stronger, nearly claw-like part of the upper cer- particularly in the structure of the last pair different localities of the Norwegian coast, in it and Adult female specimens of the present species have been Occurrence found and more appendages are much rather inferior in size body, differing moreover which more resembles that however, latter, of however is It only occasionaly and Distribution in Trondhjem In Fjord at Riser, viz., all localities Stavanger, occurred it comparatively shallow water Mediterranean (Giesbrecht) Fam Stephidae Gen Stephos, Two Remarks scribed in Vol well-defined IV of the present Scott species work of A this 3rd have genus species is now been de- added, to be described below Stephos minor, (PL Stephos minor, T Scott, Tenth Ann Report PI Specific Characters Scott II) of the Fishery VIII, figs Female Board for Scotland, Part III, p 245, 113 Body resembling in shape that of S Scotti G O Sars, the anterior division being regularly elliptical in outline evenly vaulted dorsally; greatest width about half the length and Cephalic segment very large, with the front obtusely truncated and exhibiting no trace of rostral filaments Lateral parts of last trunkal segment perfectly symmetrical and not the of the anterior /3 genital they are the l about equalling in length segment somewhat protuberant below, and about the length Caudal rami scarcely longer than succeeding segments combined division; of Urosome expanded lamellarly setae broad; apical longest the innermost but one, as usual, rather slender, and considerably exceeding the length antennae comparatively reflexed, beyond the shorter than in S scarcely Posterior segment genital urosome of the Scotti, antennae, natatory legs of a structure very similar to that in Scotti rather small, with the distal joint conical in form, some denticle inside at distance from the tip; Anterior extending, oral parts when and Last pair of legs and only armed with a single outer edge with a small bristle opposite the denticle Male much though smaller than female, with the Last pair of legs built on the 5-articulate exhibiting well-marked urosome more slender and same type differences, specific as in the other species, as seen from the figure here given Body both sexes highly pellucid and without any obvious pigment in Length Remarks to S Scotti female 0.73 mm., of male 0.60 of adult The G O Sars, but of much mm described by Scott, first present species, is nearly allied smaller size, and moreover well disting- uished by the somewhat storter anterior antennae and by the structure of the last pair of legs in both sexes Occurrence place at Several Korshavn from a specimens occasionally at Riser in about the Distribution of this form were taken depth of about 15 fathoms Remarks to in a single have also found it same depth Scottish coast (Scott) Gen Parastephos, G O author, I This genus was established in Sars the year 1903 by the present include a peculiar Copepod, of which at that time only a solitary male specimen was obtained Subsequently Mr Scott found also the female, and the perplexing characters distinguishing this sex fully prove the validity of the present genus I have been fortunate enough to find a few female specimens off the Norwegian coast, and statements given by Scott about this sex I am thus enabled to confirm the pallidus, G O Sars Parastephos (Pi Parastephos pallidus, G O Sars, Account Female Specific Characters marked divisions sharply oval form in off middle dorsally; front truncal segment completely lateral parts equalling in only slightly about behind expanded recurved spinules; usual, the largest, with fused genital a with of the /a elevated to slender, with the Body very two XLIV chief faint transverse suture behind the Last preceding one, and having the the Urosome very powerfully developed, produced IV, p 65, Pi without any traces of rostral filaments blunted, length Norway, Vol from each other, the anterior one regularly oblong segment Cephalic ill) of the Crustacea of anterior division, circular ridges segment scarcely at though not much exceeding its all anterior segments clothed densely with delicate protuberant below and, as in size the succeeding segment; anal segment well developed and of sub-cylindrical form; without any elevated ridge Caudal rami scarcely longer than they are broad; apical setae the innermost but one on left ramus remarkably produced, behind slightly divergent, being nearly twice as long as that on the right ramus the very end of the same structure in and genus, but the reflexed, to the oral parts exactly as in Last pair of legs likewise built on the of left much comparatively proximal of which the is same type in as in and pronouncedly asym- larger size being considerably longer than the leg both legs conically produced and armed outside with denticles, Anterior antennae of when Natatory legs of quite normal structure and resembling those male metrical, the male, and extending, Posterior antennas the genital segment the genus Stephos that as a right; distal joint in row somewhat remote from of 12 15 coarse the others and of larger size the in Body living animal semipellucid, of an uniform whitish grey colour, without any obvious pigmentation of adult Length Of Remarks female reaching to 2.20 this formerly observed by me form, as mm above mentioned, only the male sex was The female, as usual, is of considerably larger size, most anomalous appearance by the powerful development and The last pair of leg are also remarkable peculiar armature of the urosome by their comparatively large size, and more particularly by their conspicuous and exhibits a observed asymmetry, also that author, is found On the left side in by Scott Another asymmetry, not mentioned by the extraordinary length of one of the caudal setae on other hand has the asymmetry described by the present some author in proved to be of the male specimen at first obtained no such asymmetry was found in another the natatory legs of as accidental, quite male subsequently obtained The Occurrence specimens of this originally Sogn was taken the one female described male specimen was taken at have subsequently obtained additional remarkable form, adult females and one male Of these Skjerjehavn, outside the at I Fjord Kopervik, south west coast of Norway, the other female and the male specimen at Riser, the depth in both localities ranging from 50 to 100 fathoms Scottish coast (Scott) Distribution Farn Pseudocyclopiidee Gen Pseudocyclopia, Remarks Only Scott a single species of this genus, P stephoides Thompson, am now enabled to has hitherto been recorded from the Norwegian coast add other species, both described it is at I an earlier date by British authors, and very probable that also the remaining species, P minor and P caudata Scott, will on a further investigation be found to belong to the fauna of Norway Pseudocyclopia Giesbrechti, Wolfenden (PI IV, PI V, fig 1) Pseudocyclopia Giesbrechti, Wolfenden, Journal of the Marine Biological Association, Vol VI, No 3, p 370, PL IV Specific anterior Characters hibiting in the dorsal scarcely attaining curved in Female Body rather short and stout, with the considerably vaulted above, and somewhat compressed, ex- division aspect half front; rostral a narrow oblong form, with the greatest width Cephalic segment very large and evenly the length prominence triangular, deflexed Last truncal segment united with the preceding one and deeply emarginated behind in the middle, lateral parts obtusely anterior division; rounded genital Urosome about segment only equalling in length Vs of the slightly protuberant the length of the succeeding segments combined scarcely longer than they are broad, and below and about Caudal rami short, somewhat obliquely truncated being at the end; apical strong and partly exhibiting a dense annulation setae rather terior antennae only slightly and composed exceeding half the length of the cephalic of 17 joints, the 1st of which, apparently of the or proximal joints, is very large, almost occupying half the length paratively shorter than in P stephoides, though a the ramus; and latter 6-articulate, provided little com- on the same type as what more slender than in the in longer than the outer with the 2nd joint somewhat dilated, oval in outside with setae, the succeeding joints very small Oral parts of the structure characteristic of the genus built segment, formed by the junction Posterior antennae with the terminal part (inner ramus) of the antenna form, An- Natatory legs likewise other species, though the rami appear some- P stephoides and more distinctly spinulose at the moreover densely covered with small of short and Last rather stout, with the last joint scarcely legs pair prickles longer than the middle one and somewhat hand-shaped, terminating in strong end of the joints, those of 4th pair being diverging digitiform spines of equal length, the outermost one distinctly defined at the joint; whereas base, all spines, as Male, and slender the other form usual, distinelly smaller immediate continuation of the than female and having the urosome more 5-articulate from those parts scarcely different the as also partly the surface of the joint, coarsely spinulose Antennae, oral parts and natatory legs Last pair of legs, however, con- in female spicuously transformed and very asymmetrical; right leg long and slender, termi- nating in a somewhat flexuous point; left leg much shorter, but with the 1st joint considerably tumefied, nearly globular in form, 2nd joint tapered distally and provided 3rd joint the end with a well-marked rudiment of an appendicular ramus, at very narrow and armed the end with a slender movable claw, at outside which are attached a bundle of delicate and closely superposed lamellae Colour of the living animal not yet ascertained Length of adult Remarks from a solitary T Scott female reaching to 0.90 mm., that of male to 0.79 The present species was female specimen taken found the same species also off first the Shetland off the mm described by Mr Wolfenden isles Scottish coast, Subsequently and has given a It may easily be distinguished figure with some details of a male specimen from P stephoides by the comparatively shorter and stouter_ form of the body and more particularly by the structure of the last pair of legs in bot sexes As these appendages were somewhat damaged in the male specimen examined by Scott, the figure he gives of them has turned out to be rather imperfect Moreover the right leg is described as the left, and vice versa Copepoda Suppl Cyclopinidas Volume G O Sars, del Cyclopina norvegica, Boeck brachystylis, G O Sars litoralis, Brady PI LXIX Copepoda Cyclopinidae Cyclopidae Suppl Volume PI j G O Sars, del Cyclopina dilatata, Sars Euryte minor, Scott LXX Copepoda Ascomyzontidae Suppl Volume G O Sars, del Rhynchomyzon t falco, Giesbr PI LXXI Copepoda Acontiophoridse Suppl Volume LXXII PI ,4-fr: ' ' , G O Sars, del Acontiophorus ornatus, Brady ' Copepoda Suppl Lichomolgidae Volume PI LXXIII I \ / Q O Sars, del Hermanella dubia, G Sars Lichomolgella pusilla, G O Sars Copepoda Volume Suppl Lichomolgidae PI LXXIV i7 v I'.i '} { ^, ' / -^ A I / ' O Sars del Pseudomolgus arenicola, (Brady) f Copepoda Suppl Sapphirinidae Volume PI I r: M - r G O Sars, de Sapphirina iris, Dana LXXV ** Copepoda Suppl Sapphiriniclae Volume PI y y & i 3^ "! * i ' }} y i O Sars, del Sapphirina iris, Dana LXXVI ... the and the stronger, nearly claw-like part of the upper cer- particularly in the structure of the last pair different localities of the Norwegian coast, in it and Adult female specimens of the. .. fuller like of development in it in the rather of joints, the general Anterior antennae less robust little 16-articulate, and the aesthetasks, the Last pair of legs with the outer composed and somewhat... very if of the Calanoida, the Heterarthrandria, an arrangement would be absolutely unreasonable 12 Anterior antennae scarcely exceeding half the length of the cephalic longest segment and gradually
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