DAY/DATE
Tuesday
19/12/2023
SITE/S
Flinders Reef
PARTICIPANTS
David & Will
TYPE
Subtidal
MODE
Boat Dives
VESSEL
MV ScubaWorld
DIVE
1
2
3
SITE/S
North-West
Aladdins-East
South-West
SPECIES #
13
9
3
DURATION
52 Min
53 Min
51 Min
DEPTH/RANGE
13-16 m
12-15 m
10-14 m
TEMP.
25 C
25 C
26 C
VIS.
15 m
15 m
20+ m
SURGE
Nil
Nil
Nil
CURRENT
Slight
Nil
Moderate
COMMENTS & OBSERVATIONS
A three dive charter out of Mooloolaba with Mike McKinnon’s Scubaworld on the Big Red RIB. Amazing day of weather, crew, and dive companions. I can highly recommend the charter. Certainly a change from the worry and effort of running my own boat. Walk on and walk off. The ride out was smooth and comfortable. I was paired up with Will, who joined in the fun, hunting for sea slugs. First dive was on the western (inner) side at the northern end. The most species were sighted here, including the not-so-common Phyllidiopsis xishaensis, even with several distractions provided by Turtles, Manta Rays, Bull Rays with attendant Remora and Barracuda dropping in. The second dive was out on the eastern side around Aladdins Cave region. Here I was rewarded with the rarely sighted Murphydoris sp. 01 and the white Thuridilla – Thuridilla sp. 02. The final dive was back on inner western side towards the south, at the ”Turtle Cleaning Station”, a site heavily covered in Acropora corals a substrate mostly unsuitable for nudibranchs. The first and third dives on the western inner side were subject to currents. The water seemed to be moving along the inside face of the reef rather than the outside.
Taxonomic Diversity:
Fifteen of the twenty sighted species were nudibranchs, with 13 being dorids comprising 1 x phanerobranch (non-retractile gill), 5 x porostomes (suctorial feeders of the Phyllidiidae family), 7 x cryptobranchs (retractable gill – five belonging to the Chromodorididae family and two to the Discodorididae) and 2 were cladobranchs comprising 2 x aeolids, 0 x arminid and 0 x dendronotinid. A single head-shield slug, three sacoglossans and a single umbrella-shell slug complete the species count. If diet is considered then 13 of the 20 species sighted are spongivores. 41 specimens in total were recorded.
Our Historical Data:
– This excursion brings the number of survey dives to 104 at Flinders Reef (68 on the eastern side and 36 on the western side) since we commenced fully recording data here on 27/11/2009.
– 275 species have been recorded at this site.
– The most regularly recorded species are:
on the eastern side: Chromodoris elisabethina (91%), Phyllidiella pustulosa (57%), Thuridilla neona (54%), and Chromodoris lochi (52%);
on the western side: Chromodoris elisabethina (74%), Thuridilla sp. 04 (54%), Phyllidia picta (42%), and Phyllidiella lizae (42%);.
– This is the first occasion we have recorded Murphydoris sp. 01, Phyllidia guamensis or Phyllidiopsis xishaensis at Flinders Reef.
– This is the first occasion on which we have recorded Halgerda elegans or Verconia varians on the western side of the reef.
– A number of the sightings are relatively rare for us at these sites: we have recorded Halgerda elegans, Mariaglaja inornata, and Verconia varians only once each previously on the western side of the reef.
– Thuridilla sp. 02 is also a rare find for us, having been recorded on only three previous surveys (once on the eastern side and twice on the western side of the reef.
– We last surveyed Flinders Reef on 14/09/2018.
(Historical data courtesy of Terry Farr, who extracts it from his comprehensive database.)
Key to symbols
+++ New Species
+ First time sighted at this site
# Most commonly sighted at this site with %
TOTAL SPECIES SIGHTED: 20
SPECIES LIST – ALPHABETICAL
Bulbaeolidia alba -/2/-
Chromodoris elisabethina 3/2/- # 91%east & 74%west
Chromodoris strigata 2/-/-
Coryphellina pannae 1/-/1
Costasiella kuroshimae -/-/1
Halgerda elegans 1/-/-
Hypselodoris tyroni 2/3/-
Jorunna sp. 03 1/-/-
Mariaglaja inornata 5/3/1
Murphydoris sp. 01 -/1/- +
Phyllidia guamensis 1/-/- +
Phyllidia varicosa 1/-/-
Phyllidiella lizae -/1/-
Phyllidiella pustulosa -/2/- #57%east
Phyllidiopsis xishaensis 1/-/- +
Thorunna daniellae -/2/-
Thuridilla carlsoni 1/-/-
Thuridilla sp. 02 -/1/-
Tylodina corticalis 1/-/-
Verconia varians 1/-/-
SPECIES GROUPED BY ORDER
Nudibranchia
Dorids
Phanerobranchs
Murphydoris sp. 01 -/1/-
Cryptobranchs
Chromodoris elisabethina 3/2/-
Chromodoris strigata 2/-/-
Halgerda elegans 1/-/-
Hypselodoris tyroni 2/3/-
Jorunna sp. 03 1/-/-
Thorunna daniellae -/2/-
Verconia varians 1/-/-
Porostomes
Phyllidia guamensis 1/-/-
Phyllidia varicosa 1/-/-
Phyllidiella lizae -/1/-
Phyllidiella pustulosa -/2/-
Phyllidiopsis xishaensis 1/-/-
Cladobranchs
Aeolids
Bulbaeolidia alba -/2/-
Coryphellina pannae 1/-/1
Arminids
–
Dendronotinids
–
Cephalaspidea
Mariaglaja inornata 5/3/1
Pteropoda
–
Sacoglossa
Costasiella kuroshimae -/-/1
Thuridilla carlsoni 1/-/-
Thuridilla sp. 02 -/1/-
Umbraculoidea
Tylodina corticalis 1/-/-
Pleurobranchoidea
–
Anaspidea
–
