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| Didogobius lanceolatus Schliewen, Knorrn & Böhmer, in Schliewen, Knorrn, Böhmer, Beuck, Sonnewald et Freiwald, 2023. |
Didogobius lanceolatus sp. nov. is described from a single specimen collected from
the southern Banc d’Arguin, Mauritania. The species differs from all currently
described congeners, as well as from all species of the closely related species of the
genera Chromogobius and Gammogobius, by the combination of the following characters: (1) lanceolate caudal fin; (2) small (reduced) vs. large eyes; (3) 27 vertebrae;
(4) D2I, 13, AI, 11; (5) predorsal region in front of first dorsal fin D1 naked;
(6) body squamation reduced, with only few areas on flank covered by externally
visible cycloid scales behind pectoral origin and on caudal peduncle; (7) anterior
oculoscapular canal present, with only pores σ,κ,α,ρ; (8) posterior oculoscapular
and preopercular head canal absent; (9) suborbital row 7 close to pore α with more
than five papillae; (10) suborbital rows 2 and 4 close to orbit; (11) interorbital papillae absent. The new species appears most closely related to the type species of
Didogobius Miller 1966, D. bentuvii Miller, 1966, as it shares a set of apparently derived morphological characters, such as the lanceolate caudal fin, minute eyes and
the anterior oculoscapular canal with only pores σ,κ,α,ρ present. Phylogenetic
analysis of COI-barcoding data further suggests a close relationship with two
other species of the genus Didogobius exclusively sharing with the new species and
D. bentuvii elevated unpaired fin ray counts, i. e., D2 branched rays ≥12 (vs. ≤11 in
all other species) and A branched rays ≥11 (vs. ≤10 in all other species); these two
species are D. kochi Van Tassell, 1988 and D. schlieweni Miller, 1992. Based on the
description of new Didogobius species obviously closely related to the type species
of Didogobius, on re-examination of the single type specimen of D. bentuvii and on
the new DNA barcoding data we restrict and re-diagnose the genus Didogobius to
include only the aforementioned four species. The other former Didogobius species
are placed in two new genera, each unambiguously diagnosable on previously
established morphological data: Marcelogobius gen. nov. with M. splechtnai, M. helenae and M. janetarum, and Peter gen. nov. with the two shrimp-associated species
P. amicuscaridis and P. wirtzi.
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| Didogobius lanceolatus sp. nov. (SMF 39647, male, 65.1+20.6 mm, Mauritania, southern Banc d’Arguin, holotype). right lateral view; ventro-lateral view; images of live specimen in seawater (photos: A. Freiwald and L. Beuck). |
Class Osteichthyes Huxley, 1880
Order Gobiiformes Günther, 1880
Family Gobiidae Cuvier, 1816
Genus Didogobius Miller, 1966
Didogobius lanceolatus Schliewen,
Knorrn & Böhmer, 2023 sp. nov.
Diagnosis. Didogobius lanceolatus sp. nov. differs
from all currently described members of the genera Didogobius, Chromogobius, Marcelogobius gen.
nov. and Peter gen. nov. by the combination of
the following characters: (1) lanceolate caudal fin;
(2) small (reduced) vs. large eyes; (3) 27 vertebrae;
(4) D2I+13, AI+11; (5) predorsal region in front
of D1 naked; (6) body squamation reduced, with
only a few cycloid scales anteriorly and in tail region; (7) anterior oculoscapular canal present, with
only pores σ, κ, α, ρ; (8) posterior oculascapular and
preopercular head canal absent; (9) suborbital row
7 with more than five papillae; (10) suborbital rows
2 and 4 close to orbit.
Etymology. Latin for “with a little lance”, derived
from Latin lanceola, a diminutive term of lancea, meaning “lancet”, i.e. a small lancet. An adjective referring
to the lancet-shaped caudal fin of the new species,
a character shared in the Chromogobius-Didogobius
species complex only shared with the type species
of the genus Didogobius, D. bentuvii.
Marcelogobius Schliewen gen. nov.
Etymology. The generic name Marcelogobius gen.
nov. honours the Croatian biologist, Marcelo Kovačić,
who is the leading active goby expert for the Eastern
Atlantic, Mediterranean and Ponto-Caspian region.
Included species: The type species, M. splechtnai
(Ahnelt & Patzner, 1995) comb. nov., M. helenae (Van
Tassell & Kramer, 2014) comb. nov., and M. janetarum
Schliewen, Wirtz & Kovačić 2018 comb. nov.
Peter Schliewen gen. nov.
Etymology. The generic name Peter gen. nov. refers
to the same first name of two outstanding goby
enthusiasts at the same time, i. e. first Peter J. Miller,
the British goby systematicist, who has contributed
particularly to the knowledge of European and
African gobies more than any other goby scientist;
and second, Peter Wirtz, the tirelessly diving German naturalist and biologist, who discovered dozens
of new animal species in the marine waters of the
eastern tropical Atlantic, including the two shrimpassociated goby species Peter amicuscaridis comb.
nov. and Peter wirtzi. comb. nov. Gender masculine.
Included species: The type species, P. wirtzi
(Schliewen & Kovačić, 2008) comb. nov. and P. amicuscaridis (Schliewen & Kovačić, 2008) comb. nov.
Ulrich K. Schliewen, Alexander Hans Knorrn, Robin Böhmer, Lydia Beuck, Moritz Sonnewald and André Freiwald. 2023. Didogobius lanceolatus sp. nov., A New goby Species from Mauritania, with Diagnoses for Two New gobiine Genera (Teleostei, Gobiidae, Gobiinae). SPIXIANA. 46(1); 119-133
