Order SQUALIFORMES
Dogfish sharks
Sharks of normal cylindrical or somewhat compressed
form, without an anal fin, and with 2 dorsal fins and 5 pairs
of gill slits. The dorsal fins may have small to large spines on
their front margins. Adults 15 cm to over 6.4 m total length.
Ovoviviparous. Coastal, oceanic and deepwater benthic
sharks found in all oceans; 2 families, both in our area.
Family No.5: SQUALIDAE
by A.J. Bass, L.J.v. Campagna & P.C. Heemstra
Dogfishes
Hondhaaie
Two dorsal fins (with or without spines). Anal fin absent.
Trunk roughly circular in cross section, without any pronounced ventrolateral ridges. Five gill slits. Spiracle large.
Nictitans absent. Ovoviviparous. About 15 valid genera
with many species, 12 genera and 25 species in our area.
KEY TO GENERA
la Trunk triangular in cross-section, belly flat with
a distinct ridge on each side between P and V .............. Oxynotus
1 b Body more or less rounded in cross-section, no distinct
ridge along sides of belly ................................................... 2
2a Spines present at front of both D (in Centroscymnus
the tip of the 2nd D spine may be covered by skin, but the
presence of the spine is easily ascertained by touch) .. .............. 3
2b No spine at front of 2nd D ................................................. 8
3a Teeth in upper jaw with one cusp .............................. .......... 4
3b Teeth in upper jaw with 3 or more cusps .................... ........... 7
4a Lower teeth similar to uppers and about the same
size; upper C lobe without a subterminal notch; no
lateral grooves on D spines ........................................ Squalus
4b Lower teeth distinctly broader than upper; upper C lobe
with a subterminal notch; D spines with lateral grooves ............ 5
5a Distance from tip of snout to mouth longer than that from
mouth to level of P origins .......................................... Deania
5b Distance from snout to mouth not longer than that
from mouth to P origins .................................................... 6
6a Upper jaw teeth set close together, at least some of the
bases overlapping to form an interlocking band ...... Centrophorus
6b Upper teeth narrow, their bases not overlapping .. Centroscymnus
7a Teeth in lower jaw asymmetric, with one oblique cusp;
upper teeth with 3-5 cusps .................................... Etmopterus
7b Teeth similar in both jaws, with 3-5 cusps, erect and
symmetric, or nearly so, all along the jaw ............ Centroscyllium
8a Tip of 1st D over V ................................................... Isistius
8b Tip of 1st D well in front of V ............................................. 9
Hondhaaie
9a Base of 2nd D more than 3 times length of 1st Dbase;
vertical diameter of orbit greater than depth
of peduncle .................................................. Euprotomicrus
9b Base of 2nd D less than 3 times 1st D base; vertical
orbit diameter less than peduncle depth ............................... 10
lOa Gill slits increasing in length posteriorly,
last one longer than distance from spiracle to
1st gill slit ................................................. Euprotomicroides
lOb Gill slits subequal in length, last one much shorter than
distance from spiracle to 1st gill slit ..................................... 11
11a Lower C lobe indistinct; lower teeth with strongly
serrated, erect, large triangular cusps; lips thick
and pleated ................................................... Scymnorhinus
11b Lower C lobe quite distinct; lower teeth with smooth
or weakly serrated, oblique, small cusps .............................. 12
12a Snout as long as mouth to P or longer; rear of
1st D base closer to V bases than P bases ........ Heteroscymnoides
12b Snout shorter than mouth to P; rear of 1st Dbase
closer to V bases than P bases ................................. Somniosus
Genus Centrophoru5 Muller & Henle, 1837
Our definition of this genus includes Atractophorus Gilchrist, Encheiridiodon J.L.B. Smith, and Lepidorhinus
Bonaparte. About 6 valid species, 4 in our area. This genus
is in need of revision. The form of the denticles apparently
changes considerably with age. Second D spine often
barbed in young, but the tip usually worn down in adults.
Teeth in upper jaw of adult males with cusps more erect
than in juveniles and females.
KEY TO SPECIES
la First D higher than 2nd D; 1st D base contained
about twice in distance between D bases ............................... 2
Ib First D lower than 2nd; 1st D base contained less
than 1 V2 times in distance between D bases ............................ 3
2a Height of 2nd D not more than V2 that of 1st D; inner edge
of P markedly longer than distance from base of exposed
part of 2nd D spine to origin of upper C lobe .......... C. scalpratus
2b Height of 2nd D more than V2 that of 1st D; inner edge of P
subequal to distance from 2nd D spine to
upper C lobe .................................................. C. granulosus
3a P subtriangular, inner edge longer than anterior
edge, inner corner acutely pointed and reaching past
vertical from tip of 1st D spine ............................. C. lusitanicus
3b P not triangular, inner edge shorter than anterior
edge; inner P corner rounded or angular, but not reaching
vertical from tip of 1st D spine ............................ C. squamosus
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Dogfish sharks
Sharks of normal cylindrical or somewhat compressed
form, without an anal fin, and with 2 dorsal fins and 5 pairs
of gill slits. The dorsal fins may have small to large spines on
their front margins. Adults 15 cm to over 6.4 m total length.
Ovoviviparous. Coastal, oceanic and deepwater benthic
sharks found in all oceans; 2 families, both in our area.
Family No.5: SQUALIDAE
by A.J. Bass, L.J.v. Campagna & P.C. Heemstra
Dogfishes
Hondhaaie
Two dorsal fins (with or without spines). Anal fin absent.
Trunk roughly circular in cross section, without any pronounced ventrolateral ridges. Five gill slits. Spiracle large.
Nictitans absent. Ovoviviparous. About 15 valid genera
with many species, 12 genera and 25 species in our area.
KEY TO GENERA
la Trunk triangular in cross-section, belly flat with
a distinct ridge on each side between P and V .............. Oxynotus
1 b Body more or less rounded in cross-section, no distinct
ridge along sides of belly ................................................... 2
2a Spines present at front of both D (in Centroscymnus
the tip of the 2nd D spine may be covered by skin, but the
presence of the spine is easily ascertained by touch) .. .............. 3
2b No spine at front of 2nd D ................................................. 8
3a Teeth in upper jaw with one cusp .............................. .......... 4
3b Teeth in upper jaw with 3 or more cusps .................... ........... 7
4a Lower teeth similar to uppers and about the same
size; upper C lobe without a subterminal notch; no
lateral grooves on D spines ........................................ Squalus
4b Lower teeth distinctly broader than upper; upper C lobe
with a subterminal notch; D spines with lateral grooves ............ 5
5a Distance from tip of snout to mouth longer than that from
mouth to level of P origins .......................................... Deania
5b Distance from snout to mouth not longer than that
from mouth to P origins .................................................... 6
6a Upper jaw teeth set close together, at least some of the
bases overlapping to form an interlocking band ...... Centrophorus
6b Upper teeth narrow, their bases not overlapping .. Centroscymnus
7a Teeth in lower jaw asymmetric, with one oblique cusp;
upper teeth with 3-5 cusps .................................... Etmopterus
7b Teeth similar in both jaws, with 3-5 cusps, erect and
symmetric, or nearly so, all along the jaw ............ Centroscyllium
8a Tip of 1st D over V ................................................... Isistius
8b Tip of 1st D well in front of V ............................................. 9
Hondhaaie
9a Base of 2nd D more than 3 times length of 1st Dbase;
vertical diameter of orbit greater than depth
of peduncle .................................................. Euprotomicrus
9b Base of 2nd D less than 3 times 1st D base; vertical
orbit diameter less than peduncle depth ............................... 10
lOa Gill slits increasing in length posteriorly,
last one longer than distance from spiracle to
1st gill slit ................................................. Euprotomicroides
lOb Gill slits subequal in length, last one much shorter than
distance from spiracle to 1st gill slit ..................................... 11
11a Lower C lobe indistinct; lower teeth with strongly
serrated, erect, large triangular cusps; lips thick
and pleated ................................................... Scymnorhinus
11b Lower C lobe quite distinct; lower teeth with smooth
or weakly serrated, oblique, small cusps .............................. 12
12a Snout as long as mouth to P or longer; rear of
1st D base closer to V bases than P bases ........ Heteroscymnoides
12b Snout shorter than mouth to P; rear of 1st Dbase
closer to V bases than P bases ................................. Somniosus
Genus Centrophoru5 Muller & Henle, 1837
Our definition of this genus includes Atractophorus Gilchrist, Encheiridiodon J.L.B. Smith, and Lepidorhinus
Bonaparte. About 6 valid species, 4 in our area. This genus
is in need of revision. The form of the denticles apparently
changes considerably with age. Second D spine often
barbed in young, but the tip usually worn down in adults.
Teeth in upper jaw of adult males with cusps more erect
than in juveniles and females.
KEY TO SPECIES
la First D higher than 2nd D; 1st D base contained
about twice in distance between D bases ............................... 2
Ib First D lower than 2nd; 1st D base contained less
than 1 V2 times in distance between D bases ............................ 3
2a Height of 2nd D not more than V2 that of 1st D; inner edge
of P markedly longer than distance from base of exposed
part of 2nd D spine to origin of upper C lobe .......... C. scalpratus
2b Height of 2nd D more than V2 that of 1st D; inner edge of P
subequal to distance from 2nd D spine to
upper C lobe .................................................. C. granulosus
3a P subtriangular, inner edge longer than anterior
edge, inner corner acutely pointed and reaching past
vertical from tip of 1st D spine ............................. C. lusitanicus
3b P not triangular, inner edge shorter than anterior
edge; inner P corner rounded or angular, but not reaching
vertical from tip of 1st D spine ............................ C. squamosus
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