Bathycalanus bucklinae, Bradford-Grieve, Janet M., Blanco-Bercial, Leocadio & Boxshall, Geoffrey A., 2017

Bradford-Grieve, Janet M., Blanco-Bercial, Leocadio & Boxshall, Geoffrey A., 2017, Revision of Family Megacalanidae (Copepoda: Calanoida), Zootaxa 4229 (1), pp. 1-183 : 118-122

publication ID	https://doi.org/ 10.5281/zenodo.293480
publication LSID	lsid:zoobank.org:pub:BCDF8F6F-B8B4-4A9D-A8B8-7EDCEF1100BE
DOI	https://doi.org/10.5281/zenodo.6029190
persistent identifier	https://treatment.plazi.org/id/03FC3969-BB0F-FFC1-01BE-61B7FB8D02BE
treatment provided by	Plazi
scientific name	Bathycalanus bucklinae
status	sp. nov.

Treatment

Bathycalanus bucklinae n. sp.

( Fig. 46 View FIGURE 46 , 77–80 View FIGURE 77 View FIGURE 78 View FIGURE 79 View FIGURE 80 )

Type locality. 25.082o S, 9.584o W.

Material examined. ANTXXIV/1, Stn 8, MOC10, 2062– 2990 m, 1♀ (11.2 mm), holotype.

Type specimens. Deposited in the collection of the National Institute of Water and Atmospheric Research, New Zealand: Holotype female: NIWA 85233 View Materials (1 vial, 2 slides).

Morphological description. Following description based on holotype specimen from ANTXXIV/1, Stn 8. As for genus with following specific level features.

Female ( Fig. 77 View FIGURE 77 A–E). Total length 11.2 mm. Anterior margin of head in dorsal view produced into rounded protrusion dorsal to base of rostrum and extending into pair of small divergent spine-like processes. In dorsal view, posterior border of pedigerous somite 5 extending into transparent, asymmetrical lappets, slightly longer on right. Genital double-somite symmetrical in dorsal view, widest at about anterior one third, 1.21 times longer than wide, seminal receptacles not observed.

Antennule ( Fig. 78 View FIGURE 78 ) extending beyond caudal rami by about 4 segments. Lengths of antennule segments (µm) as follows. Measurements taken along posterior border of each segment but two (posterior (shortest) and anterior) measurements taken of ancestral segment I. I (320, 655); II–IV (399); V (209); VI (266); VII (330); VIII (367); IX (367); X–XI (695); XII (525); XIII (530); XIV (650); XV (818); XVI (916); XVII (978); XVIII (1071); XIX (1101); XX (1278); XXI (1296); XXII (897); XXIII (855); XXIV (934); XXV (877); XXVI (458); XXVII (823); XXVIII (47). Anterior and posterior borders of ancestral segments XVI–XXI smooth. Hair sensillum on ancestral segment II not accompanied by macula cribrosa ( Fig. 78 View FIGURE 78 E).

Antenna ( Fig. 79 View FIGURE 79 A) exopod segment IV with short seta extending to distal border of segment VIII and bearing short setules.

Maxillule ( Fig. 79 View FIGURE 79 D) praecoxal arthrite with 13 setae including 2 on posterior surface and 2 setae on anterior surface, one of them small; coxal endite without setae, basal endites 1 and 2 with 2 and 4 setae respectively; endopod segments with 2 (subequal), 2 (subequal), 5+1 smaller anterior surface seta.

Maxilliped ( Fig. 79 View FIGURE 79 F) syncoxal endite 4 longest, toothed seta extending half way along endopod segment 2.

Leg 1 ( Fig. 77 View FIGURE 77 F) exopod with articulation between exopod segments 2 and 3 well developed; distolateral corner of endopod segment 1 bilobed.

Male. Unknown.

Etymology. This species is named for Professor Ann Bucklin, University of Connecticut, who conceived and led the CMarZ programme.

Distribution. Bathycalanus bucklinae n. sp. is an upper abyssopelagic species taken from the type locality south of the Walvis Ridge over the Namibia Abyssal Plane in the South Atlantic at greater than 2000 m depth ( Fig. 46 View FIGURE 46 , Table 1 View TABLE 1 ).

Species comparisons. This species is related to Ba. richardi in that it has a pair of small anterior spine-like processes on the head. Nevertheless, Ba. bucklinae can be distinguished from any other Bathycalanus species by a combination of having 1) pedigerous somite 5 with long asymmetrical posterolateral lappets; 2) body somites smooth and without pustules; 3) a genital double-somite with its widest part, in dorsal view, at one third the distance from the anterior border; 4) female antennule ancestral segment II hair sensillum not accompanied by macula cribrosa; and 5) 4 setae on the second basal endite of the maxillule ( Table 10 View TABLE 10 ).