Spinoncaea ivlevi Böttger-Schnack, 2003

Böttger-Schnack, Ruth, 2003, Taxonomy of Oncaeidae (Copepoda, Poecilostomatoida) from the Red Sea. V. Three species of Spinoncaea gen. nov. (ivlevi-group), with notes on zoogeographical distribution, Zoological Journal of the Linnean Society 137 (2), pp. 187-226 : 193-195

SPINONCAEA IVLEVI ( SHMELEVA, 1966) COMB. NOV.

Synonymy

Oncaea ivlevi Shmeleva, 1966 Original description

Shmeleva (1966): 932–933, Fig. 1.1–1.9 (♀), 1.10–1.11 (♂)

Other descriptions

Shmeleva (1969): 5–8, 27, Fig. 3a–i (♀), Fig. 4a–h (♂); Malt (1982): 186–187, 193, Fig. 3a–k (♀), 4a–d (♂)

Type locality

Southern Adriatic Sea, Stn. 46: 40∞40.8¢N, 18∞50¢E; Stn: 47: 40∞57.6¢N, 18∞48.3¢E; 0– 500 m.

Material examined

See Table 3 (a).

Preliminary note

In the following, the typical, ‘robust’ form of S. ivlevi from the Red Sea main basin is described in detail. Morphological differences of a more elongate female form variant occurring in the southern Red Sea will be given below under ‘ Variability ’. The taxonomic identity of the 2 forms will be discussed by detailed comparison with specimens of S. ivlevi (Shmeleva) from the type locality in the Adriatic Sea, comparing and discussing also the taxonomic status of specimens from various other geographical locations.

Description of female

Body length (measured in lateral aspect; from anterior margin of rostral area to posterior margin of caudal rami, calculated as sum of individual somites): 400 Mm [traditional method: 338 Mm, range: 330–340 Mm, based on 5 specimens from the Red Sea].

Exoskeleton well chitinized. Prosome 2.4 times length of urosome, excluding caudal rami, 2.0 times urosome length including caudal rami. P2-bearing somite without dorso-posterior projection in lateral aspect ( Fig. 2B ). Integumental pores on prosome as indicated in Fig. 2 (A,B). Pleural areas of P4-bearing somite with rounded posterolateral corners.

Proportional lengths (%) of urosomites are 8.8: 54.2: 8.8: 9.5: 18.7. Proportional lengths (%) of urosomites and caudal rami are 7.4: 46.0: 7.4: 8.1: 15.9: 15.2.

P5-bearing somite with 2 paired midventral spinous processes ( Fig. 2E ).

Posterior margin of genital double-somite and postgenital somites with lobate hyaline frill ( Fig. 2C,D ).

Genital double-somite 1.8 times as long as maximum width (measured in dorsal aspect) and 1.4 times as long as postgenital somites combined; variation in Region – Station no./

sampling depth Specimens Preservation Collection Reg. no.

(a) Spinoncaea ivlevi

Red Sea and Gulf of Aden

M44/2–156 (300–350 m)

1♀ (r), ovig. alcohol ZMH K-40096 5♀♀ (r) alcohol ZMH K-40098

1♂ alcohol ZMH K-40097 5♀♀ (r) alcohol NHM 2001.6782–6786 1♀ (r) dissected on slides RBS

2♀♀ (r) partly dissected, antennules on slides RBS

remaining specimens in alcohol

3♂♂ undissected on slides RBS M5/5–682 (50–100 m) 1♀ (r) partly dissected, antennule on slide, RBS

remaining specimen dried out after examination M5/5–682 (150–200 m) 3♀♀ (r) dissected on slides RBS 1♀ (r), 1♂ undissected on slides RBS M5/5–708 (125–150 m) 1♀ (e) slightly damaged (left antennule and ZMH K-40099

both CR setae V missing), alcohol

1♀ (r) alcohol ZMH K-40100 M5/5–717 (100–125 m)

1♀ (e) partly dissected, urosome and P1–P4 on RBS

slides, remaining specimen in alcohol

M5/5–631 (100–150 m)

1♀ (e) undissected on slide RBS

Eastern Mediterranean Sea

M5/1–54 (100–150 m)

1♀ (r), 2♂♂ undissected on slides RBS

M5/1 - 54 (150 - 200 m) (1)

2♀♀ (e) alcohol ZMH K-40101 2♀♀ (r), 2♀♀ (e), 1♀ (int) undissected on slides RBS

1♀ (nd) dissected [dried out after examination] RBS

Adriatic Sea

1♀ (e) alcohol ZMH K-40095 1♀ (e) dissected on slides RBS

1♀ (e) undissected on slide RBS

10♀♀ (e) formaldehyde RBS

1♂ undissected on slide RBS

Indian Ocean

Equatorial Indian Ocean

2♀♀ (r), 1♀ (e) undissected on slides RBS

7♀♀ (r) formaldehyde RBS

SE Indian Ocean, off NW Cape Australia

1♀ (r), 2♀♀ (e), 3♂ ♀ undissected on slides RBS

Region – Station no./

sampling depth Specimens Preservation Collection Reg. no.

Pacific Ocean

NW Pacific, Kuroshio Extension

1♀ (r), 2♀♀ (e) undissected on slides RBS

7♀♀ (r) formaldehyde RBS

NE Pacific, off Monterey, California

1♀ (r) undissected on slide RBS

several ♀♀ (r,e) and ♂♂ formaldehyde RBS

(b) Spinoncaea humesi sp. nov.

Red Sea Type material

M44/2–156 (250–300 m)

2♀♀ (sperm.), 3♂♂ alcohol ZMH K-40103 M44/2–156 (300–350 m)

Holotype ♀ alcohol ZMH K-40084

2♀♀ alcohol ZMH K-40085

1♀ alcohol NHM 2001.6781

3♀♀, 1♂ dissected on slides RBS

M5/5–682 (150–200 m)

1♀, 1♂ dissected on slides RBS

1♀ partly dissected, antennule on slide, RBS

remaining specimen in alcohol

4♀♀, 2♂♂ alcohol M5/5–708 (125–150 m)

1♂ alcohol

Figures

Figure 1. Location of stations. ‘= VALDIVIA-Cruise 29, October 1980; -= METEOR-Cruise 5/1, January 1987; • = METEOR-Cruise 5/3b, May 1987; '= METEOR-Cruise 5/5, July/August 1987; ·= METEOR-Cruise 44/2, March 1999.

Figure 2. Spinoncaea ivlevi (Shmeleva, 1966) comb. nov., female, robust form (Red Sea). (A) Habitus, dorsal; (B) same, lateral (appendages omitted); (C) urosome, dorsal, seta V on left side missing; (D) urosome, lateral; (E) P5-bearing somite and genital double-somite, ventral; (F) caudal ramus, dorsal, lanceolate seta V shown separately; (G) antennule; (H) leg 5, dorsal; (I) same, ventral; (J) genital aperture; (K) paired egg-sac [note the scale].

Figure 3. Spinoncaea ivlevi (Shmeleva, 1966) comb. nov., female, robust form (Red Sea). (A) Antenna, lateral elements are numbered using Roman numerals, distal elements are identified by capital letters; (B) labrum, anterior; (C) same, posterior; (D) mandible, showing individual elements, which are identified by capital letters; (E) maxillule; (F) maxilla; (G) maxilliped, anterior.

Figure 4. Spinoncaea ivlevi (Shmeleva, 1966) comb. nov., female, robust form (Red Sea). (A) P1, anterior [a: second endopod segment, arrow indicating ornamentation on inner margin]; (B) P2, anterior, intercoxal sclerite not shown; (C) P3, posterior; (D) P4, anterior, intercoxal sclerite not shown.