{{Short description|Species of fish}} {{pp|small=yes}} {{Speciesbox | image = Slippery Dick, S Ocean Blvd, Boca Raton, FL, US imported from iNaturalist photo 334504434 (cropped).jpg | image_caption = Terminal phase | image2 = Slippery Dick Wrasse - Halichoeres bivittatus (cropped).jpg | image2_caption = Initial phase | status = LC | status_system = IUCN3.1 | status_ref = <ref name="iucn status 19 November 2021">{{cite iucn |author=Rocha, L. |author2=Francini, R. |author3=Craig, M. |date=2010 |title=''Halichoeres bivittatus'' |volume=2010 |article-number=e.T187482A8547710 |doi=10.2305/IUCN.UK.2010-4.RLTS.T187482A8547710.en |access-date=19 November 2021}}</ref> | taxon = Halichoeres bivittatus | authority = (Bloch, 1791) | synonyms = {{collapsible list| {{Specieslist |Labrus bivittatus|Bloch, 1791 |Labrus psittaculus|Lacépède, 1801 |Labrus multicostatus|Gronow, 1854 |Julis humeralis|Poey, 1860 |Choerojulis grandisquamis|T. N. Gill, 1863 |Choerojulis arangoi|Poey, 1876 |Platyglossus florealis|D. S. Jordan & C. H. Gilbert, 1882 }} }} | synonyms_ref = <ref name = fishbase/> }}
The '''slippery dick''' ('''''Halichoeres bivittatus''''') is a species of wrasse native to shallow, tropical waters of the western Atlantic Ocean. [[File:Slippery dick wrasse (cropped).jpg|thumb|A terminal phase male at the New York Aquarium]]
==Description== The slippery dick wrasse is a small fish that can reach a maximum length of {{convert|35|cm|abbr=on}}.<ref name=fishbase>{{FishBase|genus=Halichoeres|species=bivittatus|year=2013|month=August}}</ref> It has a thin, elongate body with a terminal mouth, and its body coloration has three phases during its life: # The terminal phase is when the fish becomes a male, so the body coloration turns to green with two longitudinal dark stripes. The head and tail are covered with pink lines; it has a small black dot up to the pectoral fin.<ref>Randall, J.E. (1996). ''Caribbean reef fishes''. T.F.H. Publications, Inc. Ltd., Hong Kong. 3rd ed.</ref> # The initial phase is when the juvenile becomes a female. The background body coloration is mainly whitish with pink shade, and the sides have two dark longitudinal stripes. The median one is usually black extending from the snout and via the eye to the base of the tail. The second one is a paler lateral stripe further below. The upper stripe incorporates a bicolored (green and yellow turning later to black) spot where it crosses the edge of the gills (this is present in all phases).<ref name=fishbase/> <!-- what? Dark triangular corners on tail. Irregular light red bands on head and on caudal fin. Shades of green.--> Intermediates vary greatly, from shades of light purple to dark brown. Juveniles are usually white and have two dark stripes, but the lower (abdominal) stripe may be faint.<ref>[http://biogeodb.stri.si.edu/bocas_database/search/species/1319 Smithsonian Tropical Research Institute Bocas del Toro Species Database]. Biogeodb.stri.si.edu (2013-09-19). Retrieved on 2018-01-07.</ref> # The juvenile phase. The body is usually whitish, still with the two longitudinal stripes and the spot up to the pectoral fin, as in the initial phase.<ref>[http://species-identification.org/species.php?species_group=caribbean_diving_guide&id=258 Marine Species Identification Portal : Slippery dick – Halichoeres bivittatus]. Species-identification.org. Retrieved on 2018-01-07.</ref>
==Distribution and habitat== The slippery dick wrasse is widespread throughout the tropical and subtropical waters of the western Atlantic Ocean. It can be found from North Carolina and Bermuda to Brazil,<ref name=fishbase/> including the Gulf of Mexico and the Caribbean Sea area.
The slippery dick wrasse is generally reef-associated at depths from {{convert|1|to|15|m|ft|abbr=on}}, but it's not common in seagrass.<ref>Lieske, E. and R. Myers, 1994. Collins Pocket Guide. Coral reef fishes. Indo-Pacific & Caribbean including the Red Sea. Harper Collins Publishers, 400 p.</ref><ref name="Böhlke, J.E 1993">Böhlke, J.E. and C.C.G. Chaplin (1993). ''Fishes of the Bahamas and adjacent tropical waters''. 2nd edition. University of Texas Press, Austin.</ref>
==Biology== [[File:Halichoeres bivittatus, Dare County, NC, USA imported from iNaturalist photo 405808598 (cropped).jpg|thumb|Juvenile, in North Carolina]] This species feeds on benthic invertebrates, including crabs, small fishes, sea urchins and ophiuroids, polychaetes, and gastropods.<ref name="Böhlke, J.E 1993"/><ref>Cervigón, F. (1993). ''Los peces marinos de Venezuela''. Volume 2. Fundación Científica Los Roques, Caracas, Venezuela.</ref>
=== Sex change === It is a protogynous hermaphrodite.<ref name="fishbase" /> The species is diandric, i.e., individuals when born can be either male or female, but females can change sex and become males. Males that are born male are "primary" males, while males that are the result of sex change are "secondary" males. The bright colour pattern of large mature males is called the "terminal phase". The less vibrant colour pattern of females and smaller males is called the "initial phase".<ref name=":0">{{Cite journal |last1=Warner |first1=Robert R. |last2=Robertson |first2=D. Ross |date=1978 |title=Sexual patterns in the labroid fishes of the western Caribbean, I the wrasses (Labridae) |journal=Smithsonian Contributions to Zoology |issue=254 |pages=1–27 |doi=10.5479/si.00810282.254 |language=en-US}}</ref>
=== Reproduction === Both terminal and initial phase male will reproduce, but while terminal phase males usually spawn in pairs within territories that they defend, initial phase males usually spawn in large groups. Terminal phase males may also occasionally join group spawning events, and initial phase males occasionally interfere with the pair spawning of terminal males.<ref name=":0" />
These fish form leks while breeding.<ref name="fishbase" /> In North Carolina, males defend temporary territories with peak spawning in May and June. Pair spawning typically occurs between females and terminal phase males; initial phase males occasionally try to insert themselves into the spawning event.
==Status and threats== This species is widespread and very common throughout much of its range in the Caribbean and Florida, although it is uncommon in northeastern Brazil. There are no major threats known to this species, and population trends are unknown. It is listed as Least Concern (LC) by the IUCN.<ref name="iucn status 19 November 2021" />
==References== {{Reflist}}
==External links== {{Commons category}} {{Wikispecies|Halichoeres bivittatus}} *[https://web.archive.org/web/20131104203753/http://species-identification.org/species.php?species_group=caribbean_diving_guide&id=258 Caribbean Diving Guide] *[https://www.marinespecies.org/aphia.php?p=taxdetails&id=158815 Marine Species] *[https://www.fishbase.se/summary/3660 Fish Base] *[https://web.archive.org/web/20150924131930/http://www.eol.org/pages/220796/details EOL.org] * {{SealifePhotos|158815}}
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Slippery dick Category:Fish of the Atlantic Ocean Category:Taxa named by Marcus Elieser Bloch Category:Fish described in 1791