Sexually Dimorphic Morphological Characters in Five North Atlantic Deepwater Skates (Chondrichthyes: Rajiformes)

Table 3

Morphometrics and meristics of male and female Richardson’s ray Bathyraja richardsoni from different areas of the North Atlantic (significant differences are given in bold, number of specimens examined are shown in parentheses, m = standard error).

	Females (14)						Males (13)
Character	Absolute			% TL			Absolute			% TL
	Min	Max	Mean	Min	Max	Mean ±m	Min	Max	Mean	Min	Max	Mean ± m
TL, mm	240.0	1530.0	924.0				182.0	1133.0	570.2
Disc, width	159.1	1042.0	626.6	64.4	72.3	68.1 ± 0.56	93.9	784.0	382.5	51.6	70.3	65.7 ± 1.45
length	121.0	922.0	525.6	50.4	60.3	56.2 ± 0.65	76.1	637.9	314.5	41.8	59.9	53.1 ± 1.59
Snout length, preorbital	21.6	211.0	118.3	9.0	15.4	12.9 ± 0.53	14.6	145.0	74.5	7.5	15.3	12.2 ± 0.78
preoral	24.5	206.6	120.5	10.2	14.5	13.2 ± 0.38	14.9	147.3	76.1	8.2	16.3	12.7 ± 0.72
prenasal	15.4	139.0	76.3	6.4	11.5	9.4 ± 0.56	12.0	102.0	52.0	5.9	11.9	9.2 ± 0.62
Orbit, horizontal diameter	11.3	31.1	20.4	1.7	5.0	2.6 ± 0.30	8.7	28.7	17.4	1.9	5.6	3.7 ± 0.40
Interorbital width	16.8	161.5	70.5	5.2	11.1	7.5 ± 0.45	9.6	117.8	41.7	5.3	10.4	6.9 ± 0.34
Spiracle length	5.3	53.3	23.2	2.0	3.5	2.6 ± 0.15	4.0	20.0	11.9	1.8	3.4	2.4 ± 0.15
Interspiracular width	28.8	180.4	104.7	9.0	12.8	11.3 ± 0.25	23.5	122.4	63.9	10.2	14.1	11.3 ± 0.27
Orbit + spiracle length	15.4	70.0	42.1	4.4	6.8	5.2 ± 0.21	11.5	52.4	28.5	4.8	7.5	5.7 ± 0.27
D1, height	5.8	20.5	13.8	1.1	2.4	1.6 ± 0.10	4.2	16.6	9.1	1.3	2.8	1.8 ± 0.13
base length	10.1	50.9	30.8	2.8	4.6	3.4 ± 0.12	9.5	38.3	19.8	2.8	5.4	3.7 ± 0.21
D2, height	5.0	20.4	12.7	1.0	2.1	1.6 ± 0.10	4.4	20.4	9.8	1.4	2.5	1.8 ± 0.11
base length	10.3	45.0	28.4	2.9	4.3	3.5 ± 0.12	9.1	36.0	19.6	2.8	5.0	3.8 ± 0.23
Interdorsal space	0.0	14.5	5.2	0.0	1.0	0.6 ± 0.08	0.0	7.9	3.6	0.0	1.0	0.6 ± 0.08
C, base length	11.4	44.2	27.1	2.8	5.5	3.8 ± 0.27	11.8	32.8	19.7	2.9	7.0	4.4 ± 0.43
Tail, postdorsal length	0.0	52.4	29.1	0.0	7.9	4.0 ± 0.65	0.0	44.2	21.9	0.0	8.1	4.4 ± 0.68
height at V-tips	8.6	47.7	25.1	2.5	3.6	2.9 ± 0.10	7.8	38.8	15.7	2.4	4.3	3.1 ± 0.16
width at V-tips	7.6	64.0	32.3	2.6	4.8	3.7 ± 0.18	10.2	45.1	21.6	3.5	5.6	4.3 ± 0.17
height at D1 origin	3.8	18.8	10.0	1.0	1.7	1.2 ± 0.06	3.3	13.4	6.3	0.9	2.0	1.3 ± 0.08
width at D1 origin	3.3	20.3	11.1	1.1	2.3	1.3 ± 0.10	4.0	15.1	7.1	1.0	2.7	1.5 ± 0.16
lateral fold length	111.1	481.0	274.0	30.9	46.3	36.5 ± 1.58	98.8	384.0	196.8	33.9	54.3	40.1 ± 1.97
Head length, ventrally	53.3	413.0	221.3	22.2	28.3	26.0 ± 0.53	44.4	264.0	133.6	20.0	28.7	25.1 ± 0.78
Mouth width	22.1	197.0	103.0	9.2	12.9	10.8 ± 0.29	14.4	130.3	58.8	7.9	11.5	9.9 ± 0.32
Internasal width	26.4	174.6	99.6	8.0	12.8	11.0 ± 0.31	16.0	124.6	62.6	8.8	14.2	10.9 ± 0.37
Nasal curtain, length	11.8	70.6	37.3	3.0	5.5	4.6 ± 0.17	6.6	37.6	24.6	3.4	12.0	5.0 ± 0.65
width each lobe	5.0	77.7	22.0	1.6	12.4	2.9 ± 0.87	2.2	20.7	10.3	1.2	2.4	2.0 ± 0.1
space between lobes	13.8	117.7	61.0	2.2	8.5	7.0 ± 0.48	12.7	84.4	42.2	5.8	8.3	7.2 ± 0.28
Gill slit length, first	2.6	26.2	14.9	1.1	1.9	1.5 ± 0.06	2.0	20.4	8.7	0.9	1.8	1.4 ± 0.08
third	3.1	30.2	17.3	1.3	2.2	1.8 ± 0.08	2.2	23.8	9.5	1.0	2.1	1.6 ± 0.08
fifth	2.2	25.5	14.0	0.8	1.9	1.5 ± 0.09	1.3	19.3	8.1	0.7	1.7	1.3 ± 0.10
Space between first gill slits	46.6	308.5	171.7	13.6	21.4	18.5 ± 0.59	27.5	235.7	102.8	14.8	20.8	17.9 ± 0.56
fifth gill slits	36.5	227.2	129.9	10.3	16.6	14.2 ± 0.51	20.9	174.5	80.2	11.1	15.9	13.9 ± 0.40
V-length, anterior lobe	19.2	149.0	77.9	6.2	10.1	8.7 ± 0.38	11.5	118.3	55.2	6.1	11.7	9.2 ± 0.59
posterior lobe	33.4	238.0	132.5	12.9	18.7	15.6 ± 0.56	20.7	147.0	79.5	11.0	18.6	14.4 ± 0.77
Clasper, postanus length	na	na	na	na	na	na	12.2	127.7	48.6	6.4	12.0	8.6 ± 0.47
Snout tip to center of anus	113.8	1010.0	539.9	46.1	66.0	56.0 ± 1.56	75.0	691.1	299.1	32.5	61.0	49.6 ± 2.05
to max. disc width	91.0	570.0	293.9	31.0	39.0	35.0 ± 0.74	32.4	386.0	170.2	9.0	36.4	31.1 ± 2.20
Center of anus to D1	90.5	566.0	298.1	25.1	37.7	31.5 ± 0.96	68.4	362.6	171.9	25.7	38.2	31.5 ± 1.22
to D2	103.0	471.0	276.4	29.3	42.9	35.3 ± 1.22	80.4	358.0	176.3	29.1	44.2	35.6 ± 1.54
to tail tip	129.1	601.0	358.4	37.4	53.8	43.1 ± 1.42	109.6	471.3	236.7	36.2	60.2	44.3 ± 2.15
Number of median thorns	12	21	16.5 ± 0.74				13	18	15.2 ± 0.46
Snout angle	70	120	90.8 ± 3.69				70	133	96.4 ± 5.41