370
1936 ; Assis 2005 ). In addition, clupeiforms possess a laterophysic connection
(Wohlfahrt 1936 ; Wilson et al. 2009 ). The macula sacculi shows the standard orientation pattern of ciliary bundles consisting of two horizontal groups in the anterior
part and two vertical groups in the posterior portion (Fig. 4c ); the macula lagenae
has a crescent shape and two orientation groups (Fig. 4c ) (Platt and Popper 1981b ).
All clupeiforms are sound pressure sensitive, detecting sounds up to at least
4000 Hz (Mann et al. 2001 ). Members of the subfamily Alosinae ( Alosa sapidissima , Brevoortia patronus ) were shown to detect ultrasound with frequencies up to
180 kHz (Mann et al. 1997 , 1998 , 2001 ). It was hypothesized that the differently
developed suspension of the middle part of the macula utriculi to the acoustic bulla
(Higgs et al. 2004 ) and/or differences in the laterophysic connection in species with
and without ultrasound detection (Wilson et al. 2009 ) account for ultrasound hearing. Avoidance of echolocating predators (dolphins, toothed whales) might have
triggered the evolution of ultrasound detection (see Popper et al. 2004 ).
Otophysans are all characterized by the otophysic connection mediated via the
Weberian apparatus (one up to four Weberian ossicles and interossicular ligaments)
(Weber 1819 , 1820 ). The Weberian apparatus connects the swim bladder with a
special perilymphatic space, the sinus impar itself contacting the transverse canal;
the transverse canal connects left and right saccules (Wohlfahrt 1932 ; von Frisch
1936 ). The lagena in otophysans is round and larger than the elongate saccule
(Fig. 1a ). The macula sacculi shows the vertical pattern of ciliary bundle orientation
(Fig. 4d, e ) (Popper and Platt 1983 ). The saccular otolith in otophysans is needlelike, generally carrying several thin fl utes; the lagenar otolith is large and round
(Adams 1940 ; Assis 2003 ). Otophysans have highly improved hearing abilities with
a wide hearing bandwidth up to several kHz and high auditory sensitivities (for an
overview of acoustical studies on otophysans see Fay 1988 ; Ladich and Fay 2013 ;
Ladich 2014a ; Ladich, this volume).
Although inner ears including ciliary bundle orientation patterns are rather uniform and hardly variable throughout the otophysans, some catfi shes show deviations from the vertical pattern on the macula sacculi. Jenkins described four vertical
groups in the anterior portion of the macula sacculi in aspredinid and doradid species (Jenkins 1974 , 1979b ). Moreover, ariid catfi shes possess a highly modifi ed
utricle with a large utricular otolith and a macula utriculi curving around the otolith
like an equatorial band whereas the ventral part of the maculi utriculi—typical of
most vertebrate utricles—is absent (Fig. 4e ). This modifi cation was discussed in
light of high auditory sensitivities in the low frequency range (Popper and Tavolga
1981 ), but could not be confi rmed in another study comparing hearing abilities of
catfi shes (Lechner and Ladich 2008 ).
Anotophysa—the sister group of the otophysans within Ostariophysi—lack a
Weberian apparatus, but have a Weberian-like (protoweberian) structure that consists of a special arrangement of ribs, muscles, and connective tissue (Rosen and
Greenwood 1970 ; Fink and Fink 1996 ). The ear of the milkfi sh Chanos chanos
resembles that of non-otophysans, with a saccule larger than the lagena, a large and
robust saccular otolith, and a standard pattern of ciliary bundles on the macula sacculi. The round form of the lagena and the rather large macula lagenae have affi niT. Schulz-Mirbach and F. Ladich
1936 ; Assis 2005 ). In addition, clupeiforms possess a laterophysic connection
(Wohlfahrt 1936 ; Wilson et al. 2009 ). The macula sacculi shows the standard orientation pattern of ciliary bundles consisting of two horizontal groups in the anterior
part and two vertical groups in the posterior portion (Fig. 4c ); the macula lagenae
has a crescent shape and two orientation groups (Fig. 4c ) (Platt and Popper 1981b ).
All clupeiforms are sound pressure sensitive, detecting sounds up to at least
4000 Hz (Mann et al. 2001 ). Members of the subfamily Alosinae ( Alosa sapidissima , Brevoortia patronus ) were shown to detect ultrasound with frequencies up to
180 kHz (Mann et al. 1997 , 1998 , 2001 ). It was hypothesized that the differently
developed suspension of the middle part of the macula utriculi to the acoustic bulla
(Higgs et al. 2004 ) and/or differences in the laterophysic connection in species with
and without ultrasound detection (Wilson et al. 2009 ) account for ultrasound hearing. Avoidance of echolocating predators (dolphins, toothed whales) might have
triggered the evolution of ultrasound detection (see Popper et al. 2004 ).
Otophysans are all characterized by the otophysic connection mediated via the
Weberian apparatus (one up to four Weberian ossicles and interossicular ligaments)
(Weber 1819 , 1820 ). The Weberian apparatus connects the swim bladder with a
special perilymphatic space, the sinus impar itself contacting the transverse canal;
the transverse canal connects left and right saccules (Wohlfahrt 1932 ; von Frisch
1936 ). The lagena in otophysans is round and larger than the elongate saccule
(Fig. 1a ). The macula sacculi shows the vertical pattern of ciliary bundle orientation
(Fig. 4d, e ) (Popper and Platt 1983 ). The saccular otolith in otophysans is needlelike, generally carrying several thin fl utes; the lagenar otolith is large and round
(Adams 1940 ; Assis 2003 ). Otophysans have highly improved hearing abilities with
a wide hearing bandwidth up to several kHz and high auditory sensitivities (for an
overview of acoustical studies on otophysans see Fay 1988 ; Ladich and Fay 2013 ;
Ladich 2014a ; Ladich, this volume).
Although inner ears including ciliary bundle orientation patterns are rather uniform and hardly variable throughout the otophysans, some catfi shes show deviations from the vertical pattern on the macula sacculi. Jenkins described four vertical
groups in the anterior portion of the macula sacculi in aspredinid and doradid species (Jenkins 1974 , 1979b ). Moreover, ariid catfi shes possess a highly modifi ed
utricle with a large utricular otolith and a macula utriculi curving around the otolith
like an equatorial band whereas the ventral part of the maculi utriculi—typical of
most vertebrate utricles—is absent (Fig. 4e ). This modifi cation was discussed in
light of high auditory sensitivities in the low frequency range (Popper and Tavolga
1981 ), but could not be confi rmed in another study comparing hearing abilities of
catfi shes (Lechner and Ladich 2008 ).
Anotophysa—the sister group of the otophysans within Ostariophysi—lack a
Weberian apparatus, but have a Weberian-like (protoweberian) structure that consists of a special arrangement of ribs, muscles, and connective tissue (Rosen and
Greenwood 1970 ; Fink and Fink 1996 ). The ear of the milkfi sh Chanos chanos
resembles that of non-otophysans, with a saccule larger than the lagena, a large and
robust saccular otolith, and a standard pattern of ciliary bundles on the macula sacculi. The round form of the lagena and the rather large macula lagenae have affi niT. Schulz-Mirbach and F. Ladich