Coricuma Watling & Breedy, 1988

Mühlenhardt-Siegel, Ute, 2021, The genus Coricuma Watling & Breedy, 1988 (Crustacea, Cumacea, Bodotriidae) in Indonesian waters, Zootaxa 5061 (2), pp. 393-400 : 393-399

Genus Coricuma Watling & Breedy, 1988

Type species: Coricuma nicoyensis Watling & Breedy, 1988

Diagnosis. “Body long and slender, pointed anteriorly; pseudorostrum moderately developed, efferent orifice anterior; eyelobe linguiform, pigmented; male and female with serrations on carapace dorsal crest; exopod only on pereiopod 1 in both sexes; pereiopod 2–5 6-articulate; male with 2 pairs of pleopods; male antenna 2 short, clasping” ( Watling & Breedy, 1988).

Species: Coricuma nicoyensis Watling & Breedy, 1988 , C. insolita n. comb. ( Petrescu, 1992).

Coricuma insolita n. comb. ( Petrescu, 1992).

Syn. Iphinoe insolita Petrescu, 1992: 4–30 , figs; 1995: 28–33, figs 2–5;— Haye, 2007: 21.

Material : 56 ovigerous ♀, 338 non-ovigerous ♀♀, 240 ♂♂, 128 mancae, 7 damaged; eastern Lembeh Island, Indonesia, 1m depth during low tide, sandy bottom with sea grass patches; ZMH K 60864 .

11 non-ovigerous ♀♀, 4 adult ♂♂, 10 mancae; Raja Ampat , Indonesia 0.3 to 0.6 m depth during low tide, sandy bottom; ZMH K 60865 .

Remarks. Both species, Coricuma nicoyensis and Iphinoe insolita identified from the material show very similar genus-level characters, i.e., a relatively short antenna 2, the presence of 2 pairs of pleopods in adult males and the presence of the exopod only on pereiopod 1. Consequently they are considered congeneric, with Coricuma insolita n. comb. representing the second species of the genus. Transferring I. insolita to the genus Coricuma clears up the diagnosis for the genus Iphinoe as in all the remaining species, wherever the males are known, adult males do have 5 pleopods in males.

The main differences between the species C. nicoyensis and C. insolita ( Table 1 ) are in the number of dorsal teeth on the carapace, the length proportion of the cephalothorax to the abdomen, the number of larger articles in the main flagellum of the first antenna, the armature and length proportion of the uropod endopod basal and distal articles, and the shape of the pleopods in males.

The intraspecific differences between the specimens from Bunaken, reported by Petrescu (1995), Lembeh Island and Raja Ampat (this study) are quite subtle ( Table 2 ):

The length proportions of the cephalothorax and abdomen: In ♂♂ from Bunaken the abdomen is clearly longer than the cephalothorax, in the ♂♂ from Lembeh Island ( Fig. 1a ) and in those from Raja Ampat ( Fig. 3a ) it is almost equal in length.

A1: The first antenna has a remarkable structure, as the main flagellum of the first antenna has two larger basal articles followed by a long structure which resembles a very big (almost as wide as the second article of the main flagellum) aesthetasc or, according to Petrescu (1995), a number of quite small articles ( Figs 2d , 3d , 4d ) in varying numbers within the specimens. Petrescu (1995) reported “2 basal well developed articles and few more distal ones (9 in holotype)” for the male, for the female he figured 2 larger basal articles in the main flagellum followed by 5 short articles. The number of the “short articles of the main flagellum” in ♂♂ is larger in the specimens from Lembeh Island ( Table 2 ) and Raja Ampat ( Fig. 3d ) compared to those from Bunaken. Also for the female Petrescu (1995) figured the accessory flagellum more than half as long as the basal article of the main flagellum.

The number of dorsomedian teeth on the ♂♂ carapace is 4–5 in the specimens from Bunaken, 3 in the Lembeh Island ♂♂ ( Fig. 1b ) and 2 in the Raja Ampat ♂♂ ( Fig. 3b ); for the ♀ Petrescu (1995) reported 5 teeth, however, there are 6–8 in the Lembeh Island ♀♀ ( Table 2 , Fig. 2b ) and 5 in the Raja Ampat ♀♀ ( Table 2 , Fig. 4b ).

Also the setation of the uropod endopod basal article differs: in ♂♂ from Bunaken there are 1 cuspidate + 5 microserrate reported, from Lembeh Island and Raja Ampat ♂♂ there are 6 microserrate ( Figs 1c , 3c ); in ♀♀ from Bunaken are 3 cuspidate + 2 microserrate reported, in the Lembeh Island ♀♀ we see 3 cuspidate + 3 microserrate setae+ serrated margin ( Fig. 2 c ), in the Raja Ampat ♀♀ there are 4 cuspidate setae + serrated margin ( Fig. 4c ).

The setation of the uropod endopod distal article is quite similar in the specimens of all regions sampled; however, the females from the Lembeh Island as well as from Raja Ampat do have, besides setations, also a serrated inner margin ( Figs 2c , 3c , 4c ) and those from Bunaken have not.

On the flagellum of antenna 2 in ♂♂ from the Lembeh Island and from Raja Ampat there are special clasping mechanisms with a verrucous basis ( Figs 1d , 3f, 3g ), only visible in higher magnification.

The specimens from Lembeh Island and Raja Ampat are obviously ( Table 2 ) conspecific. The differences between the specimens from this study and those described by Petrescu (1995) seem to be too weak to justify the designation of a new species for specimens obtained not too far away from the type locality of C. insolita n. comb.

Figures

FIGURE 1. SEM photos of Coricuma insolita n. comb. (Petrescu 1992), adult male from Lembeh Island: a: habitus, b: carapace, c: uropods, d: antenna 2, e: second antenna, detail.

FIGURE 2. SEM photos of Coricuma insolita n. comb. (Petrescu 1992), adult female from Lembeh Island: a: habitus, b: carapace, c: uropods, d: first antenna.

FIGURE 3. SEM photos of Coricuma insolita n. comb. (Petrescu 1992), adult male from Raja Ampat: a: habitus, b: carapace, c: uropods, d: first antenna, e: second antenna, f and g: second antenna, detail.

FIGURE 4. SEM photos of Coricuma insolita n. comb. (Petrescu 1992), adult female from Raja Ampat: a: habitus, b: carapace, c: uropods, d: first antenna.

Tables

TABLE 2. The intraspecific variability in Coricuma insolita n. comb. from different Indonesian regions (n.d. means: no

region	Bunaken	Lembeh Island	Raja Ampat
author	Petrescu 1995	this study	this study
depth (m)	1–5	1	0.3–0.6
Characters:
♂ body length (mm)	3.5	3.2	3.37
♀ body length (mm)	3.7	5.2	3.45
♂ length proportion cephalothorax: abdomen	0.8	0.95	0,97
♀ length proportion cephalothorax: abdomen	n.d.	1.0	0,93
A1, article 3	longest	longest	longest
♂ A1, accessory flagellum	minute	minute	minute
♀ A1, accessory flagellum	> half basal article main flagellum	minute	minute
♂ A1, main flagellum no. articles	2 bigger basal + 9 small	2 bigger + 22 small	2 bigger + 20 small
♀ A1, main flagellum no. articles	2 bigger basal + 5 small	2 bigger + 28 small	2 bigger + 20 small
♂ A2, flagellum, no of articles	16	16	16
♂ no. dorsomedian teeth on carapace	4–5	3	2
♀ no. dorsomedian teeth on carapace	5	6–8	5
♂ uropod peduncle inner margin, no. setae	12	11 microserrate setae	11 – 13 microserrate
♀ uropod peduncle inner margin, no. setae	13	11 cuspidate	11 cuspidate
♂ uropod endopod basal article, no. setae	6	6 microserrate	6 microserrate
♀ uropod endopod basal article, no. setae	5	3 cuspidate+ 3 microserrate + serrated margin	4 + serrated margin
♂ uropod endopod distal article, no. lateral setae	4	4 to 6 microserrate	4 microserrate
♀ uropod endopod distal article, no. lateral setae	4	5 microserrate + serrated margin	5 microserrate + serrated margin
♂ uropod endopod distal article, no. terminal setae	3	3 microserrate	3 microserrate
♀ uropod endopod distal article, no. terminal setae	3	1 microserrate + 2 simple	1 microserrate + 2 simple
♂ length proportion basal: distal article of endopod	1.3	1.5	1
♀ length proportion basal: distal article of endopod	1.2	1.2	1
Pleopods	rami subequal to peduncle	rami subequal to peduncle	rami subequal to peduncle