The remarkable Ponto-Caspian amphipod diversity of the lower Durso River (SW Caucasus) with the description of Litorogammarus dursi gen. et sp. nov. Author Marin, Ivan 0000-0003-0552-8456 A. N. Severtsov Institute of Ecology and Evolution of RAS, 119071, Moscow, Russia & coralliodecapoda @ mail. ru; vanomarin @ yahoo. com; https: // orcid. org / 0000 - 0003 - 0552 - 8456 coralliodecapoda@mail.ru Author Palatov, Dmitry 0000-0002-8826-9316 A. N. Severtsov Institute of Ecology and Evolution of RAS, 119071, Moscow, Russia & triops @ yandex. ru; https: // orcid. org / 0000 - 0002 - 8826 - 9316 triops@yandex.ru Author Copilaș-Ciocianu, Denis 0000-0002-6374-2365 Laboratory of Evolutionary Ecology of Hydrobionts, Nature Research Centre, Vilnius, Lithuania & denis. copilas-ciocianu @ gamtc. lt; https: // orcid. org / 0000 - 0002 - 6374 - 2365 denis.copilas-ciocianu@gamtc.lt text Zootaxa 2023 2023-06-06 5297 4 483 517 http://dx.doi.org/10.11646/zootaxa.5297.4.2 journal article 53675 10.11646/zootaxa.5297.4.2 7a696b67-414f-408d-a282-70f965926705 1175-5326 8009123 6E7C1770-D107-4FF7-A2DC-F2A693E581F1

TABLE 2. Morphological comparison between Litorogammarus gen. nov. and related genera. The terms “short” and “long” are defined as shorter or longer than the underlying segment, respectively.

Character	Litorogammarus gen. nov.	Chaetogammarus	Spirogammarus	Dinarogammarus	Echinogammarus	Pectenogammarus (= Homoeogammarus)	Iberogammarus	Marinogammarus	Parhomoeogammarus	Relictogammarus
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TABLE 2.
AI setation	Sparse, short/ long	Sparse, short	Sparse, short	Sparse, short	Sparse, short	Sparse, short/long	Sparse, short	Sparse/dense, short/long	Sparse, short	Sparse, short
AI acc. flag. articles	4–8	2–8	Up to 9	Up to 6	5–6	4	4	5–9	5	4
AII setation	Dense, long, curled	Dense, long, straight/curled/ coiled	Dense, long, coiled	Dense/sparse, long straight	Sparse/ dense, short/ moderately long, straight	Dense/sparse, long, straight	Dense, long, straight/curled	Dense, short/ long, straight	Sparse/dense, short	Sparse, short, straight
Calceoli	Absent	Absent	Absent	Absent	Absent	Absent/present	Absent?	Absent/ present	Absent/present	Absent
Head lobes	Straight, rounded	Acute/straight	Straight	Straight	Straight, rounded	Rounded, straight, acute	Straight	Rounded/ straight	Straight/rounded	Rounded
GI vs. GII propodus	Shorter	Shorter	Subequal	Shorter	Shorter	Shorter	Longer	Longer	Shorter/subequal	Longer
PIII setation	Sparse, short	Dense/sparse/ short/long, straight/curly/ coiled	Dense, long, coiled	Dense, moderately long, straight	Dense, long, straight/curled	Dense/sparse short/ long, straight/curled	Moderately dense, long, straight	Absent/ sparse/dense, short/long, straight	Dense, long, straight	Absent/weak
PV–VII setation	Sparse	Sparse	Sparse	Well-developed	Well-developed	Sparse /well- developed	Sparse to moderate	Absent/ Sparse	Moderately developed	Absent/ Sparse
Pleosomites	Bare/small setules	Bare/small setules	Bare/small setules	Bare/small setules	Well-developed setation/small setules/spines	Bare/small setules	Bare/small setules	Bare	Bare/small setules/ toothed	Bare/small setules
Urosomites	Dominated by spines	Dominated by spines	Dominated by spines	Dominated by spines	Dominated by long setae	Spines and setae/ dominated by spines	Spines and setae	Dominated by spines	Spines and setae	Dominated by spines
Epimeres II–III dist. edge	With spines	With spines	With spines	With spines	With long setae	With setae	With spines	With spines	With spines	With spines
UIII exopod setation	Moderately developed	Absent/well developed	Well-developed	Moderately developed	Well-developed	Moderately to well- developed	Absent to moderate	Weak to well- developed	Well-developed	Absent/weak
UIII endopod setation	Absent	Absent	Absent/well developed	Moderate	Moderately to well-developed	Moderately to well- developed	Moderate	Moderate to well- developed	Moderate	Absent
Telson	Longer than broad, lobes gradually tapering	As long as broad, lobes abruptly tapering/longer than broad, lobes gradually tapering	As long as broad, lobes abruptly tapering	Longer than broad, lobes gradually tapering	As long as broad, lobes abruptly tapering	As long as broad, lobes abruptly tapering/longer than broad, lobes gradually tapering	Longer than broad, lobes gradually tapering	Longer than broad, lobes gradually tapering	Slightly longer/as long as broad, lobes abruptly tapering	Longer than broad, lobes gradually tapering