Coullia Hamond, 1973

Huys, Rony, 2009, On the junior subjective synonyms of Coullia Hamond, 1973 (Copepoda, Harpacticoida, Laophontidae): an and key to species and related genera, ZooKeys 5 (5), pp. 33-40 : 36-38

Key to the species of Coullia Hamond , 1 973

The key to species below should be used with caution since several, as yet undescribed, species are known to exist ( Hicks 1977, Coull and Wells 1983, Coull et al. 1983, Fiers 1991, 1992a). Secondly, there is considerable confusion in the literature with regard to the exact setal formulae for the P2–P4 (particularly the endopods) as several minute elements have almost certainly been overlooked or tube-pores may have been misinterpreted as rudimentary setae. Finally, little is known about the sexual dimorphism expressed in the swimming legs since only the male of C. insularis has been formally described ( Table 1 ).

1 P2–P4 endopods 1-segmented or absent..................................................... 2

– P2–P4 endopods 2-segmented ....................................................................3

2 P2 endopod absent; P3 endopod ♀ quadrate; P 5 ♀ baseoendopod with 4 setae; caudal ramus nearly 2.5 times as long as wide..................... C. clysmae

– P2 endopod 1-segmented; P3 endopod ♀ about 3 times as long as wide; P 5 ♀ baseoendopod with 3 setae; caudal ramus 3 times as long as wide ............. ................................................................................................. C. heteropus

3 P1 exp-2 with 5 setae/spines; P4 exp- 3 ♀ with very long inner apical seta .... ................................................................................................................... 4

– P1 exp-2 with 4 setae/spines; P4 exp- 3 ♀ with minute (or without) inner apical seta ........................................................................................................5

4 P2 exp- 2 ♀ without inner seta, enp-2 as long as enp-1 ................................. ............................................................................... C. insularis comb. nov.

– P2 exp- 2 ♀ with inner seta, enp-2 distinctly smaller than enp-1 ................... .............................................................................. C. tongariki comb. nov.

5 Antennule ♀ 7-segmented; P 5 ♀ baseoendopod with 5 setae ....................... ................................................................................... C. platychelipusoides

– Antennule ♀ 6-segmented; P 5 ♀ baseoendopod with 4 setae ....................... ........................................................................ C. mediterranea comb. nov.

Additional notes. In addition to the type locality, Por and Marcus (1973) found C. clysmae also in algal washings at Port Taufiq, outside the Suez Canal (Gulf of Suez).

Fiers (1992a) noted that the text and figures describing the P2 and P3 are contradictory; Fig. 40 in reality illustrates the P2, not the P3, and vice versa. Coullia clysmae differs from its congeners in the complete absence of the P2 endopod; this character, and the loss of the outer spine on P1 exp-1 require confirmation.

Pallares (1975a) described C. insularis from washings of Macrocystis pyrifera (L.) and Delesseriaceae (red algae) collected in Bahía Vancouver, Isla de los Estados ( Argentina). In a subsequent paper, Pallares (1975b) recorded the species from the plankton surrounding Macrocystis beds and washings of various algae including Durvillea and Delesseriacea. Mielke (1985) added a second record from Maiquillahue, central Chile, and updated the description of the male. The only notable difference between the two populations is found in the caudal ramus which appears more slender, having concave margins and a shorter seta II (as long as seta I) in the Argentinian material. Mielke remarked that Pallares (1975a) had reversed the outer and inner margin of the caudal ramus in her text description. Pallares noted variability in the number of outer spines on P4 exp- 3 in the ♀ (2 or 3) but not in the ♁ (2); if 3 spines is the normal condition it implies that the P4 exopod is sexually dimorphic in those species that have retained that number in the female. The sexual dimorphism on the exopods of P2–P3 (exp-2 with inner seta) is probably diagnostic for all species of the genus since it is also expressed to a certain extent in the related genera Robustunguis and Psammoplatypus ( Lee and Huys 1999) .

Coullia mediterranea shares with C. clysmae the minute and unarmed proximal exopod segment of P1. It is unclear whether this indicates common ancestry or is merely the result of imperfect observation. Pesta’s (1959) record of this species is based on a single female abdomen found in a submarine cave in the Gulf of Sorrento ( Italy). Pesta gave illustrations of the P5 and caudal rami. Based on the apically recurved caudal seta V he claimed a certain similarity with L. inopinata , a species not yet recorded from the Mediterranean, but also admitted that the difference in leg 5 setation probably indicated that the specimen collected was juvenile.

The remaining three species ( platychelipusoides , heteropus , tongariki ) are known from their respective type localities (Tenerife, North Carolina, Easter Island) only. Noodt (1958) described the female antennule of C. platychelipusoides as indistinctly 8-segment-ed with a partial suture subdividing the apical segment, however, Lee and Huys (1999) reinterpreted or re-examined the 8-segmented condition reported for some species of Paralaophonte and Heteronychocamptus Lee & Huys, 1999 and concluded that the ancestral state for the family Laophontidae is 7-segmented. Coullia heteropus is thus far unique within the genus by the presence of only three elements on the female P5 baseoendopod. Hamond (1973) overlooked the minute inner distal seta on P2–P3 (and possibly P4) exp-3, and the pinnate ornamentation on the exopodal spines of P4.

Tables

Table 1. Armature formulae of Coullia species. The setal formulae of P2–P4 exp-3 have been corrected for the minute inner apical setae which may have been overlooked in some species [they are consistently present in detailed species descriptions (e.g. Mielke 1985, Gómez and Boyko 2006)]; it is possible that they are genuinely absent on P4 exp-3.

		P1	P2		P3		P4		P5
		exp-2	exp	enp	exp	enp	exp	enp	exp benp
C. clysmae	♀	4	0.0.023	absent	0.0.023	021a	0.0.022	021a	6 4
C. heteropus	♀	4	0.0.023	010	0.0.023	021	0.0.022	020	6 3
C. platychelipusoides	♀	4	0.0.023	0.020	0.0.023	0.021	0.0.022	0.011	6 5
C. mediterranea	♀	4	0.0.023	0.020	0.0.023	0.010	0.0.022	0.021	6 4
C. insularis	♀	5	0.0.023	0.020	0.0.023	0.021	0.0.023b	0.021	6 5
	♁	5	0.1.023	0.020	0.1.023	0.020	0.0.022	0.021	5 2
C. tongariki	♀	5	0.1.023	0.020	0.0.023	0.021	0.0.023	0.021	6 5

Table 1. Armature formulae of Coullia species. The setal formulae of P2–P4 exp-3 have been corrected for the minute inner apical setae which may have been overlooked in some species [they are consistently present in detailed species descriptions (e.g. Mielke 1985, Gómez and Boyko 2006)]; it is possible that they are genuinely absent on P4 exp-3.

a Por and Marcus (1973) claimed P3–P4 endopods have 3 setae; their figure of the P3 (Fig. 39) is inconclusive in this respect and requires confirmation; the tiny element between the 2 setae in both P3 and P4 may represent the apical tube-pore found in most other species (see e.g. Mielke (1985) for P4).

b According to Pallares (1975a) some specimens have only 2 outer spines (as in the ♁).