ANATOMY OF THE MELANONIDAE 



13 



dorsal fin radial 



epibranchial (numbered) 



epibranchial toothplate 



ectopterygoid 



erector and depressor dorsalis muscles 



entopterygoid 



epural 



epineural 



extrascapular 



epioccipital 



exoccipital condyle 



exoccipital cartilage 



exoccipital flange 



exoccipital 



foramen for glossopharyngeal nerve 



foramen for vagus nerve 



facial lobe 



foramen magnum 



foramen for occipital nerves 



frontal 



flexor vert trails muscle 



flexor ventralis inferioris muscle 



granular eminence 



gas-gland 



gonad 



gut 



haemal arch 



hypobranchial (numbered) 



hyomandibular fossa 



hypophysis 



hypural (numbered) 



interarcual cartilage 



intercalar 



interhyal 



infraorbitals (numbered) 



interopercle 



interradialis muscle 



kidney 



lateral ethmoid 



liver 



lateral ethmoid-palatine ligament 



mandibular-interopercular ligament 



trigeminal lobe 



Meckel's cartilage 



mesonephric duct 



mesethmoid cartilage 



metapterygoid 



myoseptal strands supporting ribs 



medulla oblongata 



cranial nerves 



nasal 



first neural arch 



nerve branch serving adductor arcus palatini muscle 



acoustic nerve 



buccalis branch of trigeminal trunk 



infraorbital branch of trigeminal trunk 



lateral line nerve 



neuromasts types 1 and 2 



nerve of supraorbital branch innervating posterior canal 



enclosed neuromast 



nasal rosette 



supraorbital branch of trigeminal 



olfactory bulb 



opercle 



olfactory tract 



parietal 



parhypural 



palatine 



pelvic bone 



pharyngobranchial (numbered) 



pc 



postcleithrum 



pfc 



posterior (diagonal) frontal crest 



phy 



posterohyal 



pmp 



postmaxillary process of premaxilla 



pop 



preopercle 



PP 



parapophysis 



prn 



prootic notch 



ps 



parasphenoid 



psl 



parasphenoid ascending laminae 



pte 



pterotic 



pts 



pterosphenoid 



ptt 



posttemporal 



pu 



preural vertebra (numbered) 



pyc 



pyloric caeca 



qu 



quadrate 



ra 



retroarticular 



Rcl 



ramus canalis lateralis nerve 



rd 



retractor dorsalis muscle 



re 



rostrodermosupraethmoid 



sb 



swimbladder 



sbp 



swimbladder pocket 



sc 



scapular 



sea 



supracarinalis anterior muscle 



scl 



supracleithrum 



so 



supraoccipital 



sop 



subopercle 



spt 



intercalar socket for posttemporal limb 



St 



stomach 



sy 



symplectic 



ul 



ural centrum 



V 



vertebra (numbered) 



vex 



ventral section of epaxialis muscle 



vhy 



ventrohyal 



vo 



vomer 



ANATOMY 



Neuromast pattern (Fig. 2). 



Melanonus has a unique pattern of free-ending neuromasts 

 covering the head in addition to those more usual neuromasts 

 contained in the sensory canals. There are two morphotypes 

 of the former: 1) the most numerous, are long, flange-like 

 structures which occur on the skin covering the upper rim of 

 the infraorbitals, the snout, cheek muscles, preoperculum 

 and top of the head; 2) button-like structures confined to 

 specific areas on the lower cheek, snout and frontal. 



The flange-like neuromasts are usually arranged longitudi- 

 nally and more or less in rows. In the snout region, individual 

 neuromasts may be slightly curved or angled to the general 

 direction of the others (Fig. 2B). On top of the head, rows are 

 more definite and those on the snout tend to converge 

 anteriorly where the organs close to the midline are larger 

 than the others (exceptional is the star-shaped arrangement 

 posterior to the medial extrascapular sensory pore in M. 

 zugmayeri); the neuromasts close to the midline on the 

 central part of the frontal are also nearly twice the length of 

 the others (Fig. 2A). In M. zugmayeri the neuromasts along 

 the anterior part of the supraoccipital have a regular arrange- 

 ment (Fig.2A) but in M. gracilis they form a pocket or 

 enclosed area. Distribution on the preoperculum is irregular 

 and sometimes sparse (the skin is often missing from this 

 region and it is not possible to make precise counts). 



The pitlines of button-like organs are in a double row near 

 the border of the snout, in a patch above the nares, as an 



