Stigmatopora narinosa, Browne & Smith, 2007

Browne, Robert K. & Smith, Kevin, 2007, A new pipefish, Stigmatopora narinosa (Syngnathidae) from South Australia, Memoirs of Museum Victoria 64, pp. 1-6 : 2-5

Stigmatopora narinosa sp. nov.

Figures 2–5 . Tables 1 , 2 .

Figured as Stigmatopora olivacea Castelnau, 1872 : Gulf Pipefish in Kuiter (2000): 199: figs A–D. Note that female in fig. C is S. argus . In contradiction to the captions these images were taken at Edithburgh, South Australia (Kuiter, pers. com).

Holotype: male, SAM F 10190 , 150 mm TL, South Australia, Edithburg Pool, 35°05'S, 137°45'E, 31 Dec 2003. Hand netted at 10.30 am while scuba diving 30 m offshore at 2-m depth MLWS, in an open bed of mixed Posidonia sp. and Zostera sp. sea-grasses, with brown algae, on a sandy rubble substrate.

Paratypes: South Australia: SAM F 10186 , 135 mm TL, Edithburgh Pool, 35°05'S, 137°45'E, 29 Dec 2004. SAM F10194 , 60 and 64 mm TL, Magazine Bay, Pt. Turton , 34°55'S, 137°20'E, 18 Jan 2004 . SAM F 10195 , 72 mm TL, Port Victoria , 34°29'S, 137°28'E, 7 Jan 2004. NMV A 29230 -001, 143, 130, 122, 131 mm TL, Edithburg Pool, 35°05'S, 137°45'E, 22 Oct 2005 . NMV A 29231 -001, 141, 117, 141, 128, 130 mm TL, Port Hughes Jetty , 34°04'S, 137°32'E, 30 Oct 2005 .

Other material examined. SAM F 7458 , 122 and 94 mm TL, Edithburgh Jetty , 35°05'S, 137° 45’E, 13 Apr 1992 . SAM F 7550 , 95 mm TL, Edithburgh Jetty , 35°05'S, 137°45'E, 15 Mar 1994 . SAM F 7551 , 73 mm TL, Edithburgh Jetty , 35°05'S, 137°45'E, 13 Apr 1992 . SAM F 10159 , 90 mm TL, Seacliff , 35°02'S, 138°31'E, 5 Mar 2003 . SAM F 10160 , 92 mm TL, Seacliff , 35°02'S, 138°31'E, 5 Mar 2003 . SAM F 10171 , 114 mm TL, Port Hughes Jetty , 34°04'S, 137°32'E, 18 Mar 1994 . F 10186 , 135 mm TL, Edithburgh Pool, 35°05'S, 137°45'E, 29 Dec 2004 . SAM F 10191 , 74 mm TL, Port Vincent , 34°46'S, 137°52'E, 1964 . SAM F 10192 , 70 mm TL, Seacliff , 35°02'S, 138°31'E, 5 Mar 2003 . SAM F 10193 , 65 mm TL, Edithburgh Jetty , 35°05'S, 137°45'E , 1981. F10194 , 60 and 64 mm TL, Magazine Bay , Pt. Turton, 34°55'S, 137°20'E, 18 Jan 2004 . F 10195 , 72 mm TL, Port Victoria, 34°29'S, 137°28'E, 17 Jan 2004 .

Specimens of S. narinosa sp. nov. (n = 7) for statistical meristic and morphometric comparison were SAM F 7458, SAM F 7550, SAM F 7551, SAM F10159, SAM F10160, SAM F10171. Comparative material of S. nigra (SAM F10185, n = 10) used for statistical comparison was collected at O’Sullivans Beach Marina (35°02'S, 138°31'E). Other comparisons were with Dawson (1982).

Diagnosis. In contrast to other described species of Stigmatopora , trunk and tail ridges, and particularly lateral trunk ridge, indistinct in fresh specimens. Lateral trunk ridge terminates 1.5 body rings posterior to anal ring. Short, wide and slightly elevated snout. 9 sub-dorsal tail rings. Distinct banded pattern in both live and preserved specimens.

Description. STR and STAR continuous, ITR and ITAR continuous. LTR not confluent with LTAR, LTR terminating about 1.5 body rings posterior to anal ring (fig. 2). Meristic and morphometric values given in Tables 1 , 2 . The opercular ridge longitudinal and angled little dorsally, prominent in juveniles, reduced in adults (fig. 5). Brood pouch (fig. 4) under the anterior portion of tail, extends for 15 to 18 rings from anal ring; pouch plates absent or vestigial, brood protected by well-developed pouch folds which develop from the inferior tail ridges and touch or overlap at ventral midline within length of 1 ring.

Holotype., DO 6.5, D 40, P 13, A 4, TR 18, TAR 68, SDTR 11.5, SDTAR 7.5, SDR 19, SD/SnL 0.14, SW/SnL 0.15, HL/TrL 0.64, SnL/TrL 0.37, SnL/HL 0.62.

Colouration. Base color variably brown, red, yellow and grey-green, tending to fade to cream, brown and red in preservative. Adults mainly grey-green above with reddish-brown or dark brown markings. Red dominates toward tip of tail with the tip frequently only bright red. Pattern of dark transverse bands on each ring with the pattern changing along length of body and varying between individuals and possibly also with age. Anterior and dorsal margins of each ring dark brown or reddish brown, distinct or smudged, form a transverse band at each joint. Bands broaden ventrally, with only thin pale line remaining in middle of rings, resulting in appearance of a series of inverted saddles. Central part of bands sometimes pale resulting in double bands. Elongated spots sometimes present in these double dark bands or bands broken, further disrupting banded pattern and giving spotted or scribbled appearance. Banding often obscured, especially on the anterior half of trunk (figs 2, 4). Similar spotting sometimes under head. Juveniles often brown or golden yellow.

Reproduction. When compared to the other Stigmatopora spp . the most distinguishing characteristics of the reproduction of S. narinosa are a lack of dorso-ventral compression in females, a specialized reproductive morphology, the number and size of the young. Sexual dimorphism characteristic of S. nigra , S. argus , and S. macropterygia is the dorso-ventral compression of the trunk which is exaggerated in the females during courtship. Female S. nigra also display bright red banding on the ventral surface during courtship.

S. narinosa has a distinctive brood pouch and potentially a greater number of brooded eggs than its congeners S. nigra or S. argus . The brood pouch is under the anterior portion of the tail and extends for 15–18 rings from the anal ring; pouch plates are absent or vestigal, and well-developed pouch folds meet on the ventral midline. The eggs of S. narinosa are deposited in two layers, a basal layer and then an external layer. In the specimen with the greatest recorded number of eggs there were 3 staggered rows of 64 basal membranous egg compartments on the tail, with this basal layer of eggs covered by a membrane with matching rows of egg pouches; a 2nd layer with 34 eggs within the brood pouch folds resulted in a total of 98 eggs. The total lengths of S. narinosa larvae at hatching are 18 mm, those of S. nigra 13 mm, and those of S. argus 32 mm. Male S. narinosa have extended brood patches from December to March, and juveniles <90 mm seen from December to March. Males of S. narinosa can mature at 113 mm. The maximum recorded brood of S. narinosa of 98 eggs was far greater than that recorded by Dawson (1982) of approximately 25 for S. nigra and 41 for S. argus (IFG 2007) .

Comparisons. The dorsal fin origin of S. narinosa is similar to that of S. nigra at the 5th to 7th trunk ring but contrasts with other Stigmatopora which have the dorsal fin origin at the 9th to 13th trunk ring. However, S. narinosa sp. nov. is easily distinguished from S. nigra in having 9, rather than 6 sub-dorsal tail rings. Other distinguishing characteristics of S. narinosa when compared to S. nigra are a greater number of dorsal rays, total sub-dorsal rings; and ratios of snout depth and snout width to snout length, lower ratios of snout length to trunk length and head length ( Tables 1 , 2 ).

S. narinosa has a distinct banded pattern in both live and dead specimens. S. nigra and S. argus also both have banding. The banding on S. nigra on the dorsal surface consists of dark bars between the ventral rings on the trunk and extending to the tail. Dark bands on the ventral surface of the trunk are wider than on the dorsal surface. There may be no banding on the dorsal surface of the trunk of S. argus or the bands may appear as narrow dark or pale bars on the trunk and anterior 3rd of the tail. S. narinosa has inverted saddle-like dark transverse bands on each ring, broadening ventrally, with only thin pale line remaining in middle of rings. The anterior and tip of tail of S. narinosa is frequently colored red to yellow with those of S. nigra and S. argus green. A further distinguishing feature of S. argus are dark spots or ocelli on the dorsal trunk.

S. nigra and S. argus have elongated narrow and shallow snouts (fig. 6). However, the snout of S. narinosa is short, wide and slightly elevated. The brood pouch of S. narinosa extends 15–18 rings from the anal ring (fig. 3). In S. argus the brood pouch extends 14–24 tail rings, in S. nigra 12–16 tail rings, and in S. macropterygia 21–24 tail rings.

Etymology: S. narinosa “naris, Latin nostril; narinosus, broadnosed” ( Brown, 1954) is named after the wide and distinctive spatulate shape of its snout (fig. 2). Kuiter (2000) gives this species as S. olivacea , and the common name ‘Gulf Pipefish’. Because this common name is used for the North American Syngnathus scovelli (Evermann and Kendall, 1896) , for S. narinosa we adopt the common name ‘Southern Gulf Pipefish’.

Distribution. S. narinosa is currently known only from South Australia along 200 km of inshore habitat from Seaciff (35°02'S, 138°31'E) on the southeastern coast of the Gulf St. Vincent, along the south-western shore of the Gulf St. Vincent from Pt. Vincent (34°46'S, 137°52'E) south to the Edithburgh Jetty (35°05'S, 137°45'E), and along the south-eastern shore of Spencer Gulf from Pt. Hughes Jetty (34°04'S, 137°32'E), at Pt. Victoria (34°29'S, 137°28'E), and south to Magazine Bay, Pt. Turton (34°55'S, 137°20'E) (fig. 7). Photographs appearing to be S. narinosa were taken at Pt. Hughes (2003) and Edithburgh Jetty (35°05'S, 137°45'E) and by Kuiter (2000) at Edithburg (in Kuiter, 2000, image title from Cape Jarvis, Kuiter pers. com.) and Pt. Victoria (34°29'S, 137°28'E). All specimens of S. narinosa have been collected or photographed in sheltered shallow open water of 1–5 m depth over a substrate of a mosaic of patches of brown algae, with Posidonia , or Zostera . The only hand-netted specimen of S. narinosa was sampled at Stansbury (34°53'S, 137°49'E) at low tide. Deeper water trawl surveys offshore from locations inhabited by S. narinosa have yielded no specimens. Deeper SCUBA surveys have not found S. narinosa . Therefore, S. narinosa appears to have a very limited inshore distribution along patches of moderate energy coastlines with low turbidity and a broken vegetation pattern of sea-grass and brown algae.

The northern sections of both the Gulf St. Vincent and Spencer Gulf are low energy coastlines with typically dense Posidonia sea-grass beds extending from low tide mark to considerable depths. They lack an open patchy mosaic of brown algae, Posidonia , and Zostera on sand and probably do not offer suitable habitat for S. narinosa . Both S. argus and S. nigra generally inhabit sea-grass beds, with the larger S. argus (TL 254 mm; Dawson, 1982) preferring the long (~ 60 cm) and wide (~ 1 cm) Posidonia sp. beds, and the smaller S. nigra (TL 162 mm, Dawson, 1982) inhabiting the short (~ 5-14 cm) and narrow (~ 2-4 mm) Zostera sp. sea-grass. Both S. argus and S. nigra are colored green to grey-green. The generally reddish/brown colour of S. narinosa would provide better camouflage among its apparently preferred habitat of mixed sea-grass and brown algae. Seasonal water temperatures at one site inhabited by S. narinosa (Edithburgh Pool; 35°05'S, 137°45'E) ranged from 12–20°C.

This restricted inshore habitat of S. narinosa may be particularly vulnerable to pollutants or exotic marine species. On the other hand, the readily accessible inshore distribution of S. narinosa could facilitate the monitoring and investigation of its populations and contribute to conservation measures. The finding of a new Stigmatopora species in shallow inshore sites adjacent to populated areas indicates the potential for other novel species of pipefish to be discovered across southern Australia.

Figures

Figure 2. (a) Side view of the head, (b) dorsal view of the head, and (c) side view of the posterior trunk and anterior tail of a male Stigmatopora narinosa sp. nov. (Paratype SAM 10186) preserved in alcohol. The sub-dorsal ring count is 12 + 8.2 = 20.2. The broad snout is particularly elevated near the tip. The ridges on the snout and trunk are less prominent in fresh specimens. The lateral trunk ridge ends across the second tail ring. Drawing by Lisa Waters.

Figure 3. Side view of Stigmatopora narinosa sp. nov. (Paratype SAM F10195). The tail tapers to a point without a caudal fin.

Figure 4. (a) Side view of the head, trunk and anterior of the tail of a male Stigmatopora narinosa sp. nov, (Holotype, SAM F10190) showing the prominent brood-pouch posterior to the vent, (b) dorsal view of the brood-pouch extending 14 tail rings from the vent, (c) ventral view of the brood pouch showing the well-developed pouch folds. This male gave birth when captured. S. narinosa is atypical of the genus in having up to 98 eggs in two layers, instead of 20–40 eggs in one layer.

Figure 5. A side (a) and dorsal (b) view of Stigmatopora nigra (upper; Kaup, 1853) and also of S. argus (lower, b,c; Richardson, 1840) from South Australia. Both species have a relatively longer more tubular snout than S. narinosa, with S. argus having a longer snout than S. nigra.

Tables

Table 1. Meristic counts for S. narinosa, and S. nigra from South Australia.

Species / counts	Dorsal	Pectoral	SDTR	SDTAR	SDR
S. nigra	36.0 ± 1.1 34–38	13.0 ± 0.0 13–13	10.57 ± 0.45 10.0–12.5	6.23 ± 0.18 4.8–7.1	16.8 ± 0.6 16.00–18.00
S. narinosa	40.8 ± 2.3 37–45	12.4 ± 0.5 12–13	11.75 ± 1.00 9.0–12.5	9.08 ± 0.17 8.2–9.8	19.8 ± 1.1 19.25–22.25
Probability	P<0.01	NS	NS	P<0.01	P<0.05

P for t- test. NS = not significant, Dorsal = dorsal ray count; Pectoral = pectoral ray count; SDTR = sub-dorsal trunk rings ngs; SDTAR = sub-dorsal tail rings; SDR = total sub-dorsal rings. Values are expressed as means ± SD, range.

Table 2. Measurement ratios for S. narinosa and S. nigra from South Australia.

Species / ratios	SD/SnL	SW/SnL	HL/TrL	SnL/TrL	SnL/HL
S. nigra	0.09 ± 0.01 0.08–0.10	0.06 ± 0.01 0.05–0.06	0.68 ± 0.13 0.59–0.76	0.43 ± 0.03 0.39–0.48	0.64 ± 0.02 0.60– 0.67
S . narinosa	0.13 ± 0.02 0.10–0.17	0.14 ± 0.03 0.10–0.18	0.66 ± 0.05 0.58–0.68	0.38 ± 0.02 0.34–0.40	0.61 ± 0.03 0.56–0.65
Probability	P<0.01	P<0.01	NS	P<0.01	P<0.01

SD = snout depth, least vertical dimension posteriad of mouth; SnL = snout length; SW = snout width; HL = head length; TrL = trunk length, length from posterior of operculum to vent. Values are expressed as means ± SD, range.

P for t-test, NS = not significant.