Aipysurus Fuscus Common Name(S): Dusky Sea Snake, Timor Reef Snake 2
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Threatened Species Nomination Form For amending the list of threatened species under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) 2014/15AssessmentPeriod The purpose of this form is to provide a nomination to the Threatened Species Scientific Committee (the Committee) for assessment of a non EPBC Act listed species/subspecies for inclusion on the list of threatened species or to nominate a species/subspecies for reassessment for consideration for listing in another category of threat. For a non-EPBC Act listed species to be eligible for listing as a threatened species it must be assessed as meeting at least one of the five criteria for listing. For a species already listed as threatened under the EPBC Act to be eligible for listing in a higher or lower category of threat it must be assessed as meeting at least one of the five criteria for a particular indicative threshold. For example, for a species listed as endangered to be found eligible for listing as critically endangered, it must meet the critically endangered indicative thresholds for at least one of the listing criteria. If there is insufficient information to enable details to be provided because of a lack of scientific data or analysis please include any information that is available or provide a statement next to the relevant question identifying that the data or analysis is not available. Please provide references in your nomination to support information provided. If you are nominating a species for removal from the list please complete the nomination form to delist a species. The Committee recognises that completing a nomination form is demanding as a result of the information required by the Committee to undertake an assessment to determine the eligibility for listing. Nominators are encouraged to seek expert advice where appropriate to assist in the completion of the nomination form. Important notes for completing this form Please complete the form as comprehensively as possible – it is important for the Committee to have as much information as possible, and the best case on which to judge a species’ eligibility against the EPBC Act criteria for listing. Certain information in this nomination is required to be provided by Division 7.2 EPBC Regulations 2000 (www.environment.gov.au/epbc/about/index.html). Nominations that do not meet the EPBC Regulations can not be provided to the Committee for consideration. All required questions are included in this nominations form. If information to answer any of the questions in this form is NOT available please state this in your answer as this is sufficient to meet the requirements of the EPBC Regulations. Reference all information and facts, both in the text and in a reference list at the end of the form. The opinion of appropriate scientific experts may be cited as personal communication, with their approval, in support of your nomination. Please provide the name of the experts, their qualifications and contact details (including employment in a state agency, if relevant) in the reference list at the end of the form. If the species is considered to be affected by climate change, please refer to the Guidelines for assessing climate change as a threat to native species (Attachment B; Part B2). Identify any confidential material and explain the sensitivity. Note that the information in the nomination (but excluding any information specifically requested by you to remain confidential) will be made available to the public and experts for comment. However, your details as nominator will not be released, and will remain confidential. Figures, tables and maps can be included at the end of the form or prepared as separate electronic or hardcopy documents (referred to as appendices or attachments in your nomination). Cross-reference relevant areas of the nomination form where needed. Note – Further detail to help you complete this form is provided at Attachment A. If using this form in Microsoft Word, you can jump to this information by Ctrl+ clicking the hyperlinks (in blue text). Details of Nominated Species or Subspecies 1. NAME OF NOMINATED SPECIES (OR SUBSPECIES) Scientific name: Aipysurus fuscus Common name(s): Dusky Sea Snake, Timor Reef Snake 2. CURRENT LISTING CATEGORY What category is the species currently listed in under the EPBC Act? (If you are nominating the species for removal from the list, please complete the nomination form for removal from the list). X Not Listed Extinct Extinct in the wild Critically Endangered Endangered Vulnerable Conservation dependent 3. 2013–2014 CONSERVATION THEME Is the current conservation theme ‘terrestrial and marine flora and fauna that would benefit from national listing’ relevant to this nomination? If so, briefly explain how. NA Transfer Information (for transferring of a species to another category) Note: If the nomination is to transfer a species between categories please complete questions 4-6. If the nomination is for a new listing please proceed to question 7. If the nomination is to remove a species from the list, please use the delisting form. 4. REASON FOR THE NOMINATION FOR CATEGORY CHANGE Please mark the boxes that apply by clicking them with your mouse. What is the reason for the nomination: Genuine change of status New Knowledge Mistake Other Taxonomic change– ‘split’ newly described ‘lumped’ no longer valid 5. INITIAL LISTING Describe the reasons for the species’ initial listing and if available the criteria under which it was formerly considered eligible 6. CHANGES IN SITUATION With regard to the listing criteria, how have circumstances changed since the species was listed that now makes it eligible for listing in another category? Species Information 7. TAXONOMY Provide any relevant detail on the species' taxonomy(e.g. authors of taxon or naming authority, year and reference; synonyms; Family and Order). Author, year: Tschudi, 1837 Synonyms: Stephanohydrafusca, (Tschudi, 1837) Class: Reptilia Order: Squamata Family: Elapidae Subfamily: Hydrophiinae 8. CONVENTIONALLY ACCEPTED Is the species conventionally accepted? If the species' taxonomy is NOT conventionally accepted, then please provide the following information required by the EPBC Regulations 2000: a taxonomic description of the species in a form suitable for publication in conventional scientific literature; OR evidence that a scientific institution has a specimen of the species, and a written statement signed by a person who is a taxonomist and has relevant expertise (has worked with, or is a published author on, the class of species nominated), that the species is considered to be a new species. YES 9. DESCRIPTION Provide a description of the species including where relevant, distinguishing features, size and social structure How distinct is this species in its appearance from other species? How likely is it to be misidentified? A. fuscus is brown, blackish-brown or purplish –brown in colour, more or less uniform, but often with obscure, faint paler cross-bands on the lower flanks. In some specimens the centre of each lateral scale is darer, resulting in faint, dark, longitudinal striations. Ventral surface is brown. A small, moderately build snake superficially resembling the larger, more heavily built Aipysurus laevis, but with darker colouration. Head shields, especially the parietals are partly fragmented, but the major shields are more or less regular. Body scales are smooth, imbricate, in 19 rows at mid-body. Ventrals 155-180, slightly notched behind. Anal divided. Subcaudals 24-37, all single. 0.6 – 0.78 metre (total adult length), tail 0.10 metre. (Cogger 2000; Smith 1926). There is very little sexual dimorphism evident except in the subcaudal scales of a sample for Ashmore Reef in 2003 and 2004. The subcaudal count for males ranged from 25 to 35 (mean = 30 , SD = 2.01, n= 15). The subcaudal scale count for females ranged from 26 to 33 (mean = 28.5, SD = 2.0 n = 15) (Francis 2006). Tubercules formed on the anterior ventral scales and the posterior ventral scales of male dusky sea snakes during the mating season (May) at Ashmore Reef. Females lacked tubercules on the scales at any time of the year (XXXXXXX pers. comm.,XXXX). Social structure The dusky sea snake is not known to form a recognisable social structure. Most sightings are of individuals or pairs. There is one report from Ashmore Reef of males protecting gravid females resting in coral heads nearing parturition; during this time the males display aggression towards divers (Guinea 2005). However, very little is known of the species’ social structure. Distinct appearance from other species The Aipysurus sea snakes are distinct from other species of sea snakes by their enlarged body scales, the wide ventral scales. Colouration is variable within species and within populations. A combination of characters separate Aipysurus fuscus from other Aipysurus species; between 155-180 ventral scales without or with only a slight median notch on the posterior border. Head shields more or less broken up and some of the supralabials divided horizontally. Less than 21 scale rows around midbody. Misidentification A. fuscus is most likely to be mistaken for its close relative A. laevis. Genetically pure individuals of these species can be distinguished by body size, number of mid-body scale rows and colour pattern, but they frequently hybridise and individuals of mixed ancestry most closely resemble A. laevis (Sanders et al. 2014). 10. DISTRIBUTION Provide a succinct overview of the species’ known or estimated current and past distribution, including international/national distribution. Provide a map if available. Is the species protected within the reserve system (e.g. national parks, Indigenous Protected Areas, or other conservation estates, private land covenants, etc.)? If so, which populations? Which reserves are actively managed for this species? Give details. A.fuscus is a Timor Sea endemic species and in the past had an already restricted distribution, only occurring at Ashmore and nearby reef complexes, Hibernia and Scott Reefs, in northern WA (Fig.1) (Cogger 2000; Smith 1926).