The true blennies are the
unscaled and blunt-nosed members of the blenniodei, often called combtooth blennies
because of their herbivorous dentation. Most of the regional blenniids are not
reef-associated but typically occupy rocky shorelines, usually in the more temperate
parts of the region. The exception is the large redlip blenny, Ophioblennius
atlanticus macclurei, which is very common on Caribbean coral reefs.
Larval
true blennies can be recognized by their blunted snout, long and continuous dorsal
and anal fins with flexible spines, a somewhat short and narrow caudal peduncle,
long strand-like pelvic fins (usually straight, not curled up over the body),
and relatively heavy markings (primarily a row of melanophores along the anal
fin base, often along with dense markings on the pectoral fins and the top of
the head). Many larvae have a prominent preopercular spine that disappears at
transition, although smaller spines usually remain on the preopercle. Larval blennioids
have large round eyes during their early life history, in contrast to larval scarids,
labrids, and gobies
in which the eye is often small or narrowed.
Among
the closely related families, blenniids can be separated from the labrisomids,
tripterygiids and chaenopsids
(other than the easily recognized Chaenopsis
spp.) by the blunt snout and having fewer dorsal fin spines than rays
(except in Hypsoblennius invemar),
and from dactyloscopids
by having a blunt snout and straight, not curled, pelvic fins.
Ophioblennius atlanticus macclurei
Ophioblennius atlanticus
larva
18.9 mm SL
San
Blas, Panama, SB86-422
Diagnosis:
A fin ray count of D-XII,19-21 A-II,20-21 indicates
Ophioblennius atlanticus macclurei. Recent phylogenetic studies (Muss et
al. 2001) suggest a split into five clades in the entire Atlantic, with genetic
divergence on the same order as usually delineates full species. Thus, the Caribbean
regional form can be considered either a subspecies of O. atlanticus or
its own species, O. macclurei. O. atlanticus
in Brazil and the eastern and southern parts of the Atlantic reportedly have a
different fin ray count: D-XII-XIII,21-23 A-II,24. (U)
Analogues:
Description:
Body thick and long with a large eye, blunted profile, and subterminal
Hypsoblennius invemar
Diagnosis:
A fin ray count of D-XII,11 A-II,13 indicates
Hypsoblennius invemar. This species is the
only Caribbean member of the family with as few
as 11-12 dorsal fin soft rays. The gill slit in
this genus is restricted and does not extend around
the isthmus (true for Hypsoblennius,
Hypleurochilus, and Chasmodes). The
remaining three regional Hypsoblennius
spp. have more median fin rays, 14-16 dorsal
fin soft rays and 14-17 anal fin soft rays:
H. hentz (continental coast US to Yucatan),
H. ionthus from
US waters (Florida and northern Gulf of Mexico),
and H. exstochilus
(from the islands of the northern Caribbean). H.
brevipinnis from the Pacific has recently
invaded through the Panama Canal, and can overlap
the fin ray count of H. invemar.
Analogues:
Description:
Body thick and long with a large eye, blunted
profile, and subterminal, relatively small mouth.
Pectoral fins long, reaching past the vent, pelvic
fins relatively short. Dorsal and anal fin bases
long, caudal peduncle short and narrow. Markings
on the head comprise a large patch of variably-sized
melanophores uniformly speckling the dorsal aspect
of the head, one midline above the tip of the upper
jaw, and two along the margin of the preopercle.
There is a large melanophore on the inner ray of
the pelvic fin not far from the origin and a row
of four or five large melanophores along the longest
lower pectoral fin ray. Along the ventral midline
there is a melanophore at the mid-abdomen and then
a row along the anal fin base (one per soft ray)
continuing onto the caudal peduncle ending at the
start of the accessory caudal fin rays. There are
several melanophores at the base of the segmented
caudal fin rays and one or two on the dorsal midline
of the caudal peduncle. Diffuse internal melanophores
line the abdominal peritoneum.
Hypsoblennius invemar
larva
11.4 mm SL
San
Blas, Panama, SB86-422
Hypleurochilus springeri
Diagnosis:
A modal fin ray count of D-XII,13 A-II,15 pect 14 indicates Hypleurochilus
spp. and Lupinoblennius vinctus. L.
vinctus has a gill slit continuous around the isthmus, separating it from
the Hypleurochilus spp. and Hypsoblennius
spp. who have restricted gill slits. There are six regional Hypleurochilus
spp. (sensu Williams in the FAO book), but only two are widespread
in the Caribbean: H. springeri and H.
pseudoaequipinnus (= Caribbean H. aequipinnus). Their modal fin
ray counts are the same, but the latter can often have 14 dorsal fin soft rays
and 16 anal fin soft rays. H. bermudensis
shares the modal fin ray count but is found in Bermuda, Bahamas, Florida and the
Gulf of Mexico only. The remaining Hypleurochilus
spp. are found in continental US waters only and have more medial fin rays:
H. multifilis and
H. caudovittatus with 14-15 dorsal fin soft rays and 16-17 anal fin soft
rays and H. geminatus with 14-15 dorsal fin
soft rays and 17-18 anal fin soft rays.
Diagnosis:
A modal fin ray count of D-XII,13 A-II,15 pect 14 indicates Hypleurochilus
spp. and Lupinoblennius vinctus. L.
vinctus has a gill slit continuous around the isthmus, separating it from
the Hypleurochilus spp. and Hypsoblennius
spp. who have restricted gill slits. There are six regional Hypleurochilus
spp. (sensu Williams in the FAO book), but only two are widespread
in the Caribbean: H.
pseudoaequipinnus (= Caribbean H. aequipinnus) and H. springeri. Their modal fin
ray counts are the same, but H. pseudoaequipinnus
can often have 14 dorsal fin soft rays and 16 anal fin soft rays. Otherwise, the
main feature separating H. pseudoaequipinnus
from its congeners is the prominent black spot between the first two dorsal spines.
H. bermudensis shares the modal fin ray count
but is found in Bermuda, Bahamas, Florida and the Gulf of Mexico only. The remaining
Hypleurochilus spp. are found in continental
US waters only and have more medial fin rays: H.
multifilis and H. caudovittatus with
14-15 dorsal fin soft rays and 16-17 anal fin soft rays and H.
geminatus with 14-15 dorsal fin soft rays and 17-18 anal fin soft rays.
