Kyphocalanus
- Dataset
- A new family and genus of calanoid copepods (Crustacea) from the abyss of the Atlantic Ocean
- Rank
- GENUS
Classification
- kingdom
- Animalia
- phylum
- Arthropoda
- class
- Maxillopoda
- order
- Calanoida
- family
- Kyphocalanidae
- genus
- Kyphocalanus
description
Description. Female. Prosome 5.1 times as long as urosome. Rostrum with two strong rami (Fig. 6 A – B). Cephalosome and somite 1 and somites 4 and 5 of prosome separate; posterior corners as triangular lobes (Fig. 6 A, C-D). Genital double-somite with attached spermatophore. Caudal rami with 4 terminal setae, 2 lateral broken, and 1 ventral seta, dorsal seta not located. Antennule broken posterior to ancestral segment XII. Setation as in type species. Antenna (Fig. 7 A) coxa with 1 seta, basis without seta, exopod of 8 free segments with 0, 1, 1, 1, 1, 1, 1, and 3 setae, about 2.3 times as long as endopod; first endopodal segment without seta, second with 3 plus 6 setae. Mandible (Fig. 7 B), gnathobase long and slender, cutting edge with 4 larger, acute teeth and a row of small teeth plus dorsal seta; basis with 2 setae, proximal one with basal part knife handle-like; exopod 5 - segmented with 5 setae, distal one distinctly smaller; endopod segment 1 without setae, segment 2 with 9 setae. Maxillule (Fig. 7 C), praecoxal endite with 3 terminal setae; coxal endite with 2 setae; proximal basal endite without seta, distal basal endite with 1 seta; endopod with 5 setae; exopod with 7 setae; coxal epipodite with 9 setae. Maxilla (Fig. 8 A – B), proximal praecoxal endite with 2 setae; distal praecoxal endite with 2 setae; proximal coxal endite with 1 seta; distal coxal endite with 2 setae; proximal basal endite with 1 spine; distal basal endite plus endopod with 8 long and thick worm-like sensory setae. Maxilliped (Fig. 7 D), syncoxa with 1 worm-like, comparably thin and short sensory seta on proximal praecoxal lobe, 2 long and thick worm-like setae setae on middle lobe, distal praecoxal lobe without setae; coxal lobe with 1 seta. Basis with 3 setae. Endopod of six segments with 2, 4, 2, 2, 2 + 1, and 4 setae. Swimming legs. P 1 (Fig. 8 C), basis with medial distal seta significantly curved with setules; endopod 1 - segmented without lateral lobe; exopod segments 1, 2, and 3 with lateral spines, the proximal spine is the longest, distal spine is the shortest; spine of exopod segment 1 exceeding base of following spine, spine of exopod segment 2 not reaching base of following spine. P 2 – P 4 broken. P 5 3 - segmented, exopod with 1 terminal attenuation and 1 subterminal inner spine, inner spine about three times length of terminal attenuation; spinules present only on right and left coxa distolaterally.
discussion
Remarks. Kyphocalanus sp. 1 differs from the type species in: i) smaller size (1.82 mm vs 2.24 mm in K. atlanticus); ii) shorter endopod of antenna (length ratio of exopod and endopod as 2.3: 1, vs 1.8 in K. atlanticus); iii) 3 setae on inner lobe of antenna endopod segment 2 (vs 4 setae in K. atlanticus); iv) 1 seta on maxilla proximal coxal endite (vs 2 setae in K. atlanticus); v) P 1 lateral spine of exopod segment 1 the longest compared to those of exopod segments 2 and 3 (vs this spine is the shortest in K. atlanticus); vi) spinules present only on the right coxa of P 5 (vs spinules present on coxa, basis and exopod of P 5 in K. atlanticus).
materials_examined
Material examined. Dissected adult female, body length 1.82 mm. Collected on 28 July 2000, above the sea bed at abyssal depths (5390 m) in the South Atlantic (16 º 18 ’ S 05 º 27 ’ E). Specimen is deposited at the Zoological Museum Hamburg (ZMH), University of Hamburg.
Name
- Homonyms
- Kyphocalanus
- Kyphocalanus
- Kyphocalanus
- Kyphocalanus