Cylix tupareomanaia Short, Trnski, and Ngātiwai, 2021

Short, Graham A. & Trnski, Thomas, 2021, A New Genus and Species of Pygmy Pipehorse from Taitokerau Northland, Aotearoa New Zealand, with a Redescription of Acentronura Kaup, 1853 and Idiotropiscis Whitley, 1947 (Teleostei, Syngnathidae), Ichthyology & Herpetology 109 (3), pp. 806-835 : 808-815

publication ID	https://doi.org/ 10.1643/i2020136
DOI	https://doi.org/10.5281/zenodo.5827732
persistent identifier	https://treatment.plazi.org/id/99248794-CA28-F401-C92D-402F8D34FAC4
treatment provided by	Diego
scientific name	Cylix tupareomanaia Short, Trnski, and Ngātiwai
status	sp. nov.

Treatment

Cylix tupareomanaia Short, Trnski, and Ngātiwai , new species

urn:lsid:zoobank.org:act:4DAADA17-DC8E-43EB-B1B8-6495E8886C05

Common Names: Māori—Tu pare o manaia, English—Manaia Pygmy Pipehorse

Figures 1–5 View Fig View Fig View Fig View Fig View Fig , Tables 1–5 View Table 1 View Table 2 View Table 3 View Table 4 View Table 5

Hippocampus jugumus: Kuiter, 2009: 93 View in CoL , figs. A, B (Poor Knights Islands, New Zealand).

Acentronura australe: Stewart, 2015: 1053 View in CoL , fig. 148.1 (Bay of Islands, New Zealand).

Idiotropiscis aotearoa: Perkins, 2017 (Whangaruru, New Zealand; http://www.inspiredtodive.com/photo-blog/ introducing-idiotropiscis-aotearoa).

Holotype.— AIM MA122274, 31.4 mm SL, female, New Zealand, Waiatapaua Bay, Whangaruru, 35°19 ' 18.7 '' S, 174°22 ' 08.1 '' E, depth 14 m, hand collected via SCUBA on vertical rock wall covered in encrusting coralline algae, bryozoans, sponges, solitary corals, turf algae, with Ecklonia in adjacent area, C. Bedford, S. Hannam, I. Middleton, G. Short, and T. Trnski, 11 April 2017 GoogleMaps .

Paratypes.— NMNZ P.046322 , 55.5 mm SL, male, New Zealand, Bay of Islands, east of Oturori Rock, 35°14 ' 53.9 '' S, 174°09 ' 35.1 '' E, depth 12–17 m, beam trawl, trip code kah0907, RV Kaharoa , shallow rocky reef and soft sediments with a mixture of Caulerpa , Ecklonia , and red and brown algae, M. Morrison, N. Bagley, NIWA, 3 September 2009 GoogleMaps ; NMNZ P.056154, 35.5 mm SL, female, New Zealand, Cavalli Islands, Cavalli Passage , 35°00 ' 50.4 '' S, 173°55 ' 26.4 '' E, depth 12.6–14.5 m, beam trawl, mixture of brown algae, Ecklonia, Caulerpa, Lissonia, rhodoliths, and assorted red and brown algae, C. and I. Middleton, NIWA, 21 April 2014 GoogleMaps .

Diagnosis.— See generic diagnosis.

Description.— Morphometric and meristic characters of the three type specimens listed in Table 1 View Table 1 . Trunk rings 13–14; tail rings 35–36; anal-fin rays 4; subdorsal rings 3 (spans one trunk ring and two tail rings); dorsal-fin rays 14; anal-fin rays 4; pectoral-fin rays 14. Body slender; head large relative to body, angled ventrally approximately 25° from the principal body axis, the dorsal profile pyramidal in lateral aspect, rising steeply from snout to elevated and prominent supraoccipital; distinct cup-like crest (SC) present anterodorsally on the supraoccipital well behind the eye, height moderate, pentamerous in dorsal view, divided transversally into two concave sections ( Figs. 3 View Fig , 4 View Fig ); cleithral and supracleithral ridge prominent ( Fig. 4 View Fig ); posterior margins of pentamerous crest on supraoccipital fused and equal in height to cleithrum; anterior nuchal plate absent; posterior nuchal plate present with bony dorsomedial crest; large gap between the supraoccipital and posterior nuchal plate; gill openings small, bilateral; rim of orbit with prominent dorsolateral and ventral ridges, fluted with rugose sculpturing; opercular ridge low, entire, angled dorsally toward gill opening; swelling of gular region posteroventrally of eye, forming a transverse pair of blunt protuberances; pectoral-fin base without distinct ridges, one strongly elevated ventrolateral bulge ( Fig. 4 View Fig ); dorsal-fin origin on 12 th trunk ring, fin base elevated; superior trunk ridge discontinuous with superior tail ridge below dorsal-fin base; lateral trunk ridge continuous with inferior tail ridge; inferior tail ridge ends on anal trunk ring; dorsum of anteriormost two trunk rings distinctly broader than posterior trunk rings; trunk in lateral view narrowest at 1 st and 2 nd trunk rings where angle of head forms from body axis, broadest at 5 th trunk ring; principal body ridges distinct and moderately elevated; tail rings of uniform depth over most of length, becoming progressively shorter and smaller near posterior tip; tail prehensile; scutella not evident.

Large spine present on dorsal midline of snout on the ethmoid area, at confluence with the anterior ends of supraorbital ridges, its height extended well above level of nares; none to two smaller medial spines anterior to the large spine on the snout, on the mesethmoid bone (principal dorsal spine and one anterior spine in paratype NMNZ P.056154, principal spine with anterior dorsal spines or elevations absent in paratype NMNZ P.046322); distinct median frontal spine at convergence of anterior edges of the cup-like supraoccipital crest, protruding anteriorly; four lateral head spines, one large double and rugose lateral head spine directly below the cup-like supraoccipital crest, three small blunt spines on operculum aligned 55–58° relative to the ventral axis of the head, the dorsal and ventral blunt spines connecting to terminal elements of the opercular ridge; large, conspicuous midventral conical spines on the cleithral symphysis and the first trunk ring between the pectoral-fin bases ( Figs. 3 View Fig , 5 View Fig ); two spines on cleithral ring, large rugose spine anterior to ventral third of pectoral-fin base, moderate-sized spine at ventral extent of head; small spine present posterolaterally of the pectoral-fin base ( Figs. 3 View Fig , 5 View Fig ); superior trunk ridges with spines of small to moderate size, enlarged blunt spines dorsally on 3 rd, 6 th, 10 th, 11 th, and 12 th rings, all bearing dermal flaps; lateral trunk ridges with moderate-sized spines on each trunk ring starting at 2 nd ring with enlarged spines on 3 rd, 6 th, and 10 th rings; inferior trunk ridges with moderate-sized spines starting at 3 rd ring with enlarged spines on 3 rd, 6 th, and 10 th rings; subdorsal spines four, superior trunk ridge ending with two subdorsal spines, the anteriormost spine large and conspicuous, superior tail ridge commencing with two subdorsal spines, posteriormost spine reduced, in alignment with larger subdorsal spines above; superior tail ridge spines well developed anteriorly, except on first and second ring, with enlarged spines on 3 rd, 4 th, 7 th, and 11 th tail ridges, gradually reducing in size to 22 nd trunk ring; lateral tail ridge spines absent; inferior tail ridge spines well developed to 8 th tail ring. Simple and branched dermal appendages present on head: long simple appendages extending anteriorly from dorsal rim of orbit, long and branched appendages ventrodorsally of each eye.

Cylix tupareomanaia exhibits strong sexual dimorphism with an enclosed brood pouch in male paratype NMNZ P.046322 ( Fig. 2 View Fig ). The brood pouch is located along the ventral midline of the tail below the anteriormost ten tail rings. It is enclosed by ten arcuate bony extensions ( Fig. 4 View Fig ) that extend ventrolaterally from the anterior ventral plate ridges of the tail, and progressively reduce in size posteriorly. The ten brood pouch plates are similar in appearance, whereas the posteriormost pouch plate is diminutive in size.

Coloration.— Holotype in life ( Fig. 6A View Fig ), head, trunk, and tail red; ventrolateral margin of trunk pale red to white; dorsum of head and snout speckled with fine white dots; pentamerous crest on supraoccipital red; snout spines, supraoccipital spine, anterior continuations of supraorbital ridges, and dorsal rim of orbit pale brown to white; white band extending from just behind the eye, grading posteriorly into a reticulated pattern of irregular, roundish quadrilaterals delineated by white coloration, concentrated on operculum and pectoral-fin base; reticulated pattern diffused laterally on head, pale brown to white; dorsal-fin base white with reticulated pattern, proximal third of dorsal-fin red; two parallel rows of rounded quadrilaterals present on trunk and tail rings, four quadrilaterals per ring; medioventral conical spines on the cleithral symphysis and the first trunk ring between the pectoral-fin bases pale brown to white. Fleshy appendages, pale brown to white, present on the frontal spine, principal snout spine, dorsum of rim of orbit, ventrolateral of snout, 3 rd and 6 th superior trunk ridge spines, and 3 rd and 7 th superior tail ridge spines. Other individuals of C. tupareomanaia observed at the type location and the Poor Knights Islands exhibited red and white countershading coloration or background color typically uniformly pale orange to dark red, respectively ( Fig. 6B–F View Fig ). In alcohol, head and body color pale cream to light brown. Fins hyaline.

Distribution and habitat.— Cylix tupareomanaia is thus far known only from Taitokerau Northland, New Zealand, including Pēwhairangi (Bay of Islands), Nukutaunga (Cavalli Islands), Tawhiti Rahi and Aorangi (Poor Knights Islands), and the coastal headlands off Whangaruru ( Fig. 7 View Fig ). At the type locality, C. tupareomanaia was observed in mixed habitat on a vertical rock wall that was covered in encrusting coralline algae, bryozoans, sponges, solitary corals, and turf algae, and which faced a rocky outcrop exposed to the open ocean. The rock wall was subject to moderate ocean swell as was evident from the accumulated debris of detached and decomposed algae on the sandy to rubble bottom of the channel at a depth of 17– 18 m. The holotype was collected below the Ecklonia radiata kelp line; it was observed moving about in close proximity to another individual of the same species, which appeared to represent a male–female pair. Additional reef fishes observed on and at the base of the rock wall included: Gobiopsis atrata (Gobiidae); Forsterygion flavonigrum, F. maryannae, and Notoclinops segmentatus (Tripterygiidae); Aplodactylus arctidens (Aplodactylidae); Coris sandeyeri and Notolabrus tetricus (Labridae); Chromis dispilus (Pomacentridae); and Chrysophrys auratus (Sparidae).

Species composition and biodiversity around the North Island of New Zealand indicate subdivision of inshore marine reef ichthyofauna into three regional biogeographic groups or eco-regions, including: western North Island coast; northeastern North Island coast and offshore islands; and Manawatāwhi Three Kings Islands ( Brook, 2002). Cylix tupareomanaia may be restricted to the warm temperate waters off the north-eastern coast of the North Island and its offshore islands where it has been collected and observed. The coastal headlands and offshore islands are strongly influenced by oceanic water masses and reflect higher overall species diversity ( Brook, 2002); therefore, the new taxon may not occur in the other cooler regional biogeographic areas. Its occurrence further north and south, however, may be confirmed by comprehensive sampling for this cryptic species. The new species is likely endemic to temperate New Zealand; no observations as of yet have been recorded at Rangitāhua the Kermadec Islands, where more than 90% of the coastal ichthyofauna are of subtropical and tropical Indo-Pacific origin, in temperate or tropical Australia, including its offshore subtropical territories of Lord Howe and Norfolk Islands, nor in New Caledonia ( Allen et al., 1976; Francis, 1993; Francis and Randall, 1993; Johnson, 1999; Hutchins, 2001; Gomon, 2007; Fricke et al., 2011; Larson et al., 2013; Francis and Duffy, 2015; Trnski et al., 2015; Clark et al., 2017).

Cryptic fish assemblages on temperate rocky reefs in New Zealand are dominated by the highly diverse triplefins (Tripterygiidae) and clingfishes (Gobiesocidae) and exhibit a high degree of endemism ( Paulin and Roberts, 1993; Hickey et al., 2009; Roberts et al., 2015; Conway et al., 2017, 2018). Other diminutive cryptic reef species recorded include the blennies (Blenniidae), kelpfishes (Clinidae), gobies (Gobiidae), and pipefishes and seahorses ( Syngnathidae ). The recent discovery of the highly cryptic C. tupareomanaia is therefore a noteworthy addition to reef fish diversity in New Zealand based on the fact it hadn’t been collected or observed in numerous biodiversity surveys of temperate marine ichthyofauna previously conducted in a wide range of habitats. These surveys were carried out in estuaries, shallow coastal bays, seagrass meadows, mangrove forests, open mainland coasts, peninsulas, nearshore islands, and passages within the Bay of Islands ( Nicholson, 1979; Nicholson and Roberts, 1980; Francis et al., 2005, 2011; Kelly, 2007; Jones et al., 2009; Gordon et al., 2010), throughout northern New Zealand ( Willan et al., 1979; Brook, 2002; Morrison et al., 2002, 2014; Francis et al., 2005; Leathwick et al., 2006; Edgar et al., 2013), along the coast of the East Cape Region ( Roberts and Stewart, 2006), at various inshore and offshore islands, including Manawatāwhi Three Kings Islands ( Hardy et al., 1987), Cavalli Islands ( Nicholson, 1979), the Poor Knights Islands ( Russell, 1970; Kelly, 2007), Aotea Great Barrier Island ( Roberts et al., 1986; Sivaguru and Grace, 2004), the Mokohinau Islands ( Housley, 1980), Hen Island ( Willis, 1995), Cuvier Islands ( Housley et al., 1981), Ahuahu Grea Mercury Island ( Grace, 1976), Aldermen Islands ( Grace, 1973), the Chatham Islands ( Roberts, 1991), in the South Island ( Francis, 1979; Leathwick et al., 2006; Gordon et al., 2010; Francis et al., 2011; Morrison et al., 2014), and the sub-Antarctic Auckland Islands ( Kingsford et al., 1989).

Cylix tupareomanaia is currently known from very few collected specimens and observations, which suggests that this species occurs in low abundance throughout its range, is hard to find due to its diminutive size and excellent crypsis, only occasionally occurs within SCUBA depths, or is simply rare in the regions where surveys have been conducted. These inferences are supported by the fact that representatives of Idiotropiscis in southern Australia are uncommon in its respective distributions; only two records currently exist for I. larsonae , and seven for I. australe (OZCAM museum record search; https://ozcam.ala.org.au/occurrences/search? taxa - Idiotropiscis #tab_recordsView).

Etymology.— The species epithet tupareomanaia is a neologism gifted by kaumātua (tribal elders) of Ngātiwai and references Home Point adjacent to the type locality, referred to by Ngātiwai as Tu Pare o Huia, meaning ‘‘the plume of the huia’’; the huia was a bird that became extinct in the early 20 th century. Tu Pare o Manaia translates as ‘‘the garland of the Manaia.’’ The pare, or garland, references the pentamerous head crest of the new species, and Manaia is the Māori name for a seahorse, and is also an ancestor that appears as a stylized figure used in Māori carvings representing a guardian.

Remarks.— Apparent ontogenetic differences in morphological features of the head were observed between the specimens of C. tupareomanaia examined herein ( Fig. 2 View Fig ). The smallest female ( Fig. 2A View Fig , AIM MA122274, 31.4 mm SL, holotype) exhibits a cup-like crest on the supraoccipital that is highly elevated anteriorly, distinct median supraoccipital spine at convergence of anterior edges of the coronet, protruding well anteriorly; three dorsal spines at midline of snout on mesethmoid bones, exceptionally large principal dorsal spine at confluence with anterior continuations of supraorbital ridges, the two anterior dorsal spines small, and the lateral head spine directly ventral of the cup-like supraoccipital crest consists of distinct but small paired spines. The morphological features in the larger female paratype ( Fig. 2B View Fig , NMNZ P.056154, 35.5 mm SL) are less pronounced: the median supraoccipital spine presents as a distinct but blunt spine protruding anteriorly, the snout possesses two dorsal spines, the principal spine and one small anterior spine, and the lateral head spine directly ventral of the bony pentamerous bony crest consists of small but merged paired spines. In contrast, the adult male paratype ( Fig. 2C View Fig , NMNZ P.046322, 55.5 mm SL) exhibits a cup-like supraoccipital crest that is low, less elevated, angled somewhat posteriorly, and cup-like in dorsal view, the median frontal spine a minute but discernible ridge, wedge-like in appearance, one large principal spine at midline of snout, and the lateral head spine directly ventral of the pentamerous bony crest is merged as one rugose spine.