Biology
(
الإنجليزية
)
المقدمة من Arkive
Denise's pygmy seahorse can often be observed during the daytime swimming across the surface of the sea fan on which it lives, and is generally more active than the common pygmy seahorse (4).
Very little is known about the reproductive behaviour of this species, although pregnant individuals have been found in February, May and October, indicating that breeding may occur year-round. Unusually, it is males and not females who brood the young in seahorses. However, while in most species the fertilised eggs develop in a fully enclosed pouch on the underside of the tail, in Denise's pygmy seahorse and common pygmy seahorse males, embryos are housed within the trunk region, without a separate pouch structure. Sexual maturity in Denise's pygmy seahorse occurs at just 13.3 mm of length (4).
Conservation
(
الإنجليزية
)
المقدمة من Arkive
There are currently no conservation measures targeting this species.
Description
(
الإنجليزية
)
المقدمة من Arkive
Denise's pygmy seahorse is a master of camouflage, its orange colouration and body tubercles exactly matching the stems and polyps of its gorgonian sea fan hosts (4). This relatively delicate seahorse has a thin body, long neck, short snout, a very long, prehensile tail (4) (5), and is one of the smallest of all seahorse species, typically measuring less than just 2 cm in height (1). Although similar to the common pygmy seahorse (H. bargibanti), Denise's pygmy seahorse is more smooth-skinned, showing comparatively fewer and less developed tubercles (2). In addition, males and females show greater differences in their body shape than in the common pygmy seahorse, with the female having a relatively slender, elongate trunk, while that of the male is noticeably more rounded (4).
Habitat
(
الإنجليزية
)
المقدمة من Arkive
Found only on gorgonian sea fans Annella reticulata, Muricella and Echinogorgia, at depths of between 13 and 90 m (1).
Range
(
الإنجليزية
)
المقدمة من Arkive
Widespread in the Western Pacific, including in waters around Indonesia, Malaysia, Micronesia, Palau, Papua New Guinea, Philippines, Solomon Islands and Vanutu (1) (6).
Status
(
الإنجليزية
)
المقدمة من Arkive
Classified as Data Deficient (DD) on the IUCN red List 2006 (1), and listed on Appendix II of CITES (3).
Threats
(
الإنجليزية
)
المقدمة من Arkive
There is currently insufficient data on the distribution and abundance of Denise's pygmy seahorse, and major threats to the species remain unknown. However, its small size and attractive colouration make it possible that this seahorse could be collected for the aquaria trade (1).
Diagnostic Description
(
الإنجليزية
)
المقدمة من Fishbase
Color in life plain orange with slightly darker rings around tail; when preserved, pale orange with tiny dark brown flecks on the nape of the neck and all over in some specimens. Diminutive in size. Anal fin small or absent. Rings on trunk 12; on tail 28-29. Body fleshy with inferior and ventral trunk ridges reduced to separated cross-shaped spicules embedded in the skin. Nuchal plate rounded without a raised coronet. Snout length ca. 30% in HL. Head depth ca. 50% in HL. No spines above the eye. Trunk depth (between the 9th and 10th trunk rings) ca. 7% in SL (female) and 10-15% in SL (male). The angles of certain body ridges sometimes developed into rounded tubercles (distinctly fewer and less developed compared with H. bargibanti) (Ref. 47053).
- Recorder
- Estelita Emily Capuli
Life Cycle
(
الإنجليزية
)
المقدمة من Fishbase
Male carries the eggs in a brood pouch (Ref. 205).
Morphology
(
الإنجليزية
)
المقدمة من Fishbase
Dorsal soft rays (total): 14
- Recorder
- Estelita Emily Capuli
Biology
(
الإنجليزية
)
المقدمة من Fishbase
Lives in association with gorgonian seafans (Annella reticulata, Muricella sp., and Echinogorgia sp.). Master of camouflage, with their coloration and body ornamentation in the form of tubercles, can match the stems and polyps of their gorgonian hosts (Ref. 47053). Ovoviviparous (Ref. 205). The male carries the eggs in a brood pouch which is found under the tail (Ref. 205).
- Recorder
- Estelita Emily Capuli
Denise's pygmy seahorse
(
الإنجليزية
)
المقدمة من wikipedia EN
Hippocampus denise, also known as Denise's pygmy seahorse[3] or the yellow pygmy seahorse, is a seahorse of the family Syngnathidae native to the western Pacific.
Description
Denise's pygmy seahorse is a small fish which can reach a maximum length of approximately 2.4 cm, which makes it one of the smallest representatives of the seahorses.[4] This pygmy seahorse has a short snout, slender body with a prehensile tail. Its body is either completely smooth or provided with some polyp-like tubercles, in which case these are fewer and less developed than Hippocampus bargibanti. Its coloration ranges from yellow, more or less bright, to orange with often small dark spots and sometimes darker bands on the tail.[5]
Distribution and habitat
This pygmy seahorse has been reported from several locations in the western Pacific, including Indonesia, Vanuatu, Palau, Malaysia, the Solomon Islands and Micronesia. It can be found at depths between 13 and 100 m, generally hiding in fields of gorgonians (e.g., Annella, Muricella and Echinogorgia).[4][5]
Biology
Denise's pygmy seahorse uses adaptive camouflage, changing its color to match that of the surrounding gorgonians.[4] It feeds on small crustaceans and other zooplankton.[6] An individual will stay on a single coral for the duration of its entire life. The species is ovoviviparous, and it is the male who broods the eggs in its ventral brood pouch. The latter includes villi rich in capillaries that surround each fertilized egg creating a sort of placenta supplying the embryos. When fully grown, pups are expelled from the pocket and become autonomous.[5] Males have been recorded as giving birth to 6-7 pups after 11 days of gestation, and carrying out four sequential pregnancies of the same gestation length.[7]
Conservation status
The species is relatively rare and only few data relating to the population as well as its actual distribution exist. Because of this lack of information and the rarity of the species, Denise's pygmy seahorse is currently classified as Data Deficient by the IUCN.[1] Internationally, it is also listed in Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) this means that it is on the list of species not necessarily threatened with extinction, but in which trade must be controlled in order to avoid utilization incompatible with their survival.[1]
Naming
The common name and the specific name honour the diver and underwater photographer Denise Tackett, who died in 2015; she was diving with Sara Lourie, one of the describers of H. denise, when she first encountered this species in the Lembeh Strait in 1999.[8]
References
-
^ a b c Kuo, T.-C.; Pollom, R. (2017). "Hippocampus denise". IUCN Red List of Threatened Species. 2017: e.T41716A54909161. doi:10.2305/IUCN.UK.2017-3.RLTS.T41716A54909161.en. Retrieved 14 November 2021.
-
^ "Appendices | CITES". cites.org. Retrieved 2022-01-14.
-
^ Scales, Helen (2009). Poseidon's Steed: The Story of Seahorses, From Myth to Reality. Penguin Publishing Group. p. 136. ISBN 978-1-101-13376-7. Retrieved 9 June 2019.
-
^ a b c Froese, Rainer; Pauly, Daniel (eds.) (2015). "Hippocampus denise" in FishBase. 10 2015 version.
-
^ a b c Lourie, S.A.; Randall, J.E. (2003). "A New Pygmy Seahorse, Hippocampus denise (Teleostei: Syngnathidae), from the Indo-Pacific". Zoological Studies. 42 (2): 284–291.
-
^ "Denise' Pygmy Seahorse, Hippocampus denise Lourie & Randall 2003". Fishes Of Australia.
-
^ Smith, R. E.; Tibbetts, I. R. (2008). "Mating and birth of Denise's pygmy seahorses (Hippocampus denise) observed in the wild". Coral Reefs. 27 (3): 617. doi:10.1007/s00338-008-0373-8.
-
^ Sara Lourie (12 January 2016). "In memory of Denise Tackett". Project Seahorse. Retrieved 19 May 2018.
Denise's pygmy seahorse: Brief Summary
(
الإنجليزية
)
المقدمة من wikipedia EN
Hippocampus denise, also known as Denise's pygmy seahorse or the yellow pygmy seahorse, is a seahorse of the family Syngnathidae native to the western Pacific.
