Corresponding author: Koraon Wongkamhaeng (
Academic editor: Rachael Peart
During a scientific survey, a new genus of driftwood hopper was found in mangrove roots in Ko Kut District, Trat Province, Thailand. We placed this new genus,
Wongkamhaeng K, Dumrongrojwattana P, Sumitrakij R, Keetapithchayakul TS (2022)
The family
Herein, we describe a 4-dentate noncuspidactylate palustral amphipod with basis of pereopod 7 without a posterodistal lobe as a new genus and species of the family
Amphipods were collected from driftwood, rotting logs and mangrove roots (
The generic name,
Mangrove forest near Ban Ao Prao Beach (
Driftwood hoppers (virtually confined to rotting driftwood where they live in galleries, consuming rotting driftwood and reproducing with relatively small broods).
The new genus clearly belongs to
The new genus is closely related to
Comparison of diagnostic characteristics in different protorchestiid genera.
Genus | LMD lacinia mobilis | G1 sexual dimorphism | Carpi of P4:P3 | P6–7 sexual dimorphism | P7 postero- distal lobe | U1 outer ramus | U2 outer ramus marginal setae | U3 robust setae on peduncle | U3 ramus | Number of setae per telsonic lobe | |
---|---|---|---|---|---|---|---|---|---|---|---|
|
well developed | 4-dentate | absent, palm obtuse | subequal | absent | present | linear without marginal setae | present | 1–4 | bud-like | 3–6 |
|
present | 4-dentate | absent, palm transverse | longer | unknown | present | spoon-shape with marginal setae | absent | 1 | linear | 2 |
|
absent | 4-dentate | absent, palm transverse | longer | absent | present | linear without marginal setae | absent | 3 | linear | 1–2 |
|
well developed | 4-dentate | present, palm transverse | longer | present | present | linear without marginal setae | absent | 2 | linear | 2 |
|
absent | 5-dentate | absent, palm transverse | longer | unknown | present | linear without marginal setae | absent | 2 | linear | 1 |
|
absent | 5-dentate | absent, palm transverse | subequal | absent | present | linear without marginal setae | absent | 3 | linear | 2 |
absent | 4-dentate | present, palm transverse | longer | present | absent | linear with marginal setae | absent | 2 | linear | 2 |
Only one protochestiid amphipod had been previously reported from Thailand.
The new genus is similar to
The new genus is identifiable using the following key to genera of
1 | Uropod 3 peduncle with 4 robust setae |
|
– | Uropod 3 peduncle with less than 4 robust setae |
|
2 | Uropod 3 peduncle with 3 robust setae |
|
– | Uropod 3 peduncle with less than 3 robust setae |
|
3 | Maxilliped palp article 2 distomedial lobe absent; mandible left lacinia mobilis 4-dentate; pereopod 4 carpus shorter than carpus of pereopod 3 |
|
– | Maxilliped palp article 2 distomedial lobe present; mandible left lacinia mobilis 5-dentate; pereopod 4 carpus subequal to carpus of pereopod 3 |
|
4 | Uropod 3 peduncle with 1 robust seta |
|
– | Uropod 3 peduncle with 2 robust setae |
|
5 | Mandible left lacinia mobilis 5-dentate |
|
– | Mandible left lacinia mobilis 4-dentate |
|
6 | Uropod 1 outer ramus without marginal robust setae; basis of pereopod 7 with a posterodistal lobe |
|
– | Uropod 1 outer ramus with marginal robust setae; basis of pereopod 7 without a posterodistal lobe |
|
As for the genus unless otherwise stated.
Driftwood hoppers, living inside rotten logs and mangrove roots in the softest part under the bark. The mangrove forest is located near a small creek 50 meters from the beach. The sediment in the forest is muddy sand mixed with leaf litter.
Mangrove forest near Ban Ao Prao Beach (
The specific epithet refers to the habitat of this amphipod, which is also found inside mangrove roots.
(
(
Map showing distribution of genera in the family
Mangrove wood, inside roots and rotting logs.
Thailand, Ko Kut District, Inner Gulf of Thailand.
Most species of
According to the recent checklist of the amphipods of Southeast Asia (
This study is a part of the research project “Diversity of amphipods along coastal area of Koh Kut, Trat Province” under the Plant Genetic Conservation Project under the Royal initiative of Her Royal Highness Princess Maha Chakri Sirindhorn. This work was financially supported by the Office of the Ministry of Higher Education, Science, Research and Innovation of Thailand and the Thailand Science Research and Innovation, Higher Education, Science, Research and Innovation of Thailand through the Kasetsart University Reinventing University Program 2021 and grants from the Kasetsart University Research and Development Institute (KURDI), Kasetsart University, Bangkok, Thailand. In addition, we are grateful to the Department of Zoology, Faculty of Science, Kasetsart University for the laboratory facilities.
Video of living
Mp4 file.
Video of living