Morphology data of Ascorhynchus orthostomum
Identification keys
Main Ref. Child, C.A., 1998
Appearance refers to

Sex attributes

specialized organs
different appearance
different colors
remarks

Descriptive characteristics of juvenile and adult

Striking features
Body shape lateral
Cross section
Dorsal head profile
Type of eyes
Type of mouth/snout
Position of mouth
Diagnosis Trunk fully segmented, first 3 segment posteriors with cowlings capped by low mediodorsal cones. Lateral processes longer than their diameters, with low conical dorso-distal tubercles. Neck as long as its diameter, oviger bases placed halfway between first lateral processes and expansion at chelifore insertion. Ocular tubercle broad, low, pointed lateral tubercles. Ocular tubercle low cone. Eye large, darkly pigmented. Proboscis elongate, longer than trunk length, cylindrical, without divisions, with rounded oral surface. Abdomen long, slender, inflated distally, extending to distal rim of fourth leg second coxae. Chelifore scapes 1 segment, cylindrical, curved inward, longer than twice their diameters, armed with few short distal setae. Chelae as atrophied bumps, carried retracted within scape tips. Palps 10 segmented, fifth segment, inflated, distal 5 segments slender, each slightly curved, with few ventral setae, some longer than segment diameters. Oviger 10 segmented, fifth segment longer than fourth; fifth and sixth segments with lateral rows of few setae. Strigilis well formed, segments short distally, with denticulate spines in the formula 13: 7: 6: 6, in two rows, spines with two lateral serrations per side. Terminal claw about 0.6 length of terminal segment, almost straight, without teeth. Legs fairly long; first tibiae the longest segments; longest segment armed with dorsal, lateral, and ventral rows of very short setae. Femur with fewer short setae; cement glands paired, each with single low cribriform pore. Tarsus 0.9 length of propodus, both armed with row of very short sole spines and fewer short dorsal setae. Claw slender, moderately curved, slightly more than half propodal length. Female slightly larger in all measurements except oviger, ocular tubercle smaller, tarsus slightly longer than those of male.
Ease of Identification

Meristic characteristics of Ascorhynchus orthostomum

Lateral Lines Interrupted: No
Scales on lateral line
Pored lateral line scales
Scales in lateral series
Scale rows above lateral line
Scale rows below lateral line
Scales around caudal peduncle
Barbels
Gill clefts (sharks/rays only)
Gill rakers
on lower limb
on upper limb
total
Vertebrae
preanal
total

Fins

Dorsal fin(s)

Attributes
Fins number
Finlets No. Dorsal   
Ventral  
Spines total
Soft-rays total
Adipose fin

Caudal fin

Attributes

Anal fin(s)

Fins number
Spines total
Soft-rays total

Paired fins

Pectoral Attributes  
spines     
soft-rays   
Pelvics Attributes  
Position    
spines     
soft-rays   
Main Ref. (e.g. 9948)
Glossary (e.g. cnidaria)
Comments & Corrections
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