Morphology Data of Microthrissa minuta
Identification keys
Main Ref. Whitehead, P.J.P., 1985
Appearance refers to
Bones in OsteoBase

Sex attributes

Specialized organs no special organs
Different appearance males alike females
Different colors males alike females

Descriptive characteristics of juvenile and adult

Striking features none
Body shape lateral fusiform / normal
Cross section compressed
Dorsal head profile more or less straight
Type of eyes more or less normal
Type of mouth/snout more or less normal
Position of mouth terminal
Type of scales cycloid scales

Diagnosis: Body moderately deep, its depth about 22-30% of standard length; scutes strongly keeled, 1 or 2 before base of first pectoral fin ray, 11-12 pre-pelvic and 6-8 post-pelvic scutes; snout pointed; lower jaw not or slightly projecting, included in upper when mouth closed, with small teeth limited to anterior part; pre-maxilla with 12-30 small conical teeth directed inwards; maxilla blade slender, more than 3 times as long as deep, upper edge with a ridge flared outward; posterior supra-maxilla small, spatulate, shaft as long as blade; lower gillrakers 18-22 (Ref. 188, 47399, 93833). Also characterized by 37-43 scales in a longitudinal series and anal fin with 18-21 rays (Ref. 47399). It resembles Microthrissa royauxi, which has fewer gillrakers but more anal fin rays, 14-17 and 23-27 respectively (Ref. 188). It is distinguished from Microthrissa whiteheadi by a lower number of teeth on the pre-maxilla, 12-30 vs. 32-40 in M. whiteheadi; and additionally by a higher number of lower gillrakers, 18-22 vs. 14-18, a lower number of anal fin rays, 18-21 vs. 20-25, and a lower number of pre-pelvic scutes, 11-12 vs. 13-16 (Ref. 46514, 47399).

Description: Body depth 21.7-30.0% of standard length; head length 11.1-12.7% of standard length (Ref. 188, 93833). Lower jaw not or slightly projecting; premaxilla with 12-30 conical teeth directed inwards; maxillary with 10-25 small conical teeth (Ref. 47399, 93833). First gill arch with 18-22 gillrakers on lower limb, 27-32 total gillrakers (Ref. 47399). Dorsal fin origin closer to snout than caudal fin base, inserted behind pelvic fin base; dorsal fin with 12-15 fin rays; anal fin with 18-21 fin rays; pectoral fin with 10-13 fin rays; pelvic fin with 1 unbranched and 6-7 branched rays (Ref. 47399, 93833). Cycloid scales; 37-43 on longitudinal line (Ref. 188, 47399). Scutes strongly keeled; 11-12 pre-pelvic scutes, with 1-2 scutes without ascending arms before base of pectoral fin, other 10 pre-pelvic scutes with ascending arms; 1 subpelvic scute without ascending arms; 6-8 post-pelvic scutes with ascending arms (Ref. 188, 93833). Number of vertebrae 40-44; with 20-23 abdominal vertebrae and 19-22 caudal vertebrae (Ref. 47399).

Colouration: Colouration of preserved specimens yellow greyish, occiput blackish by presence of numeral melanophores; a weak pigmented trace on caudal peduncle ending in a small black spot at base of lower lobe of caudal fin (Ref. 47399, 93833).

Ease of Identification

Meristic characteristics of Microthrissa minuta

Lateral Lines Interrupted: No
Scales on lateral line
Pored lateral line scales
Scales in lateral series 37 - 43
Scale rows above lateral line
Scale rows below lateral line
Scales around caudal peduncle
Barbels 0
Gill clefts (sharks/rays only)
Gill rakers
on lower limb 18 - 22
on upper limb
total 27 - 32
total 40 - 44


Dorsal fin(s)

Attributes no striking attributes
Fins number 1
Finlets No. Dorsal   
Spines total 0 - 0
Soft-rays total 12 - 15
Adipose fin absent

Caudal fin

Attributes forked; more or less normal

Anal fin(s)

Fins number 1
Spines total 0 - 0
Soft-rays total 18 - 21

Paired fins

Pectoral Attributes  more or less normal
Spines     0
Soft-rays   10 - 13
Pelvics Attributes  more or less normal
Position    abdominal  before origin of D1
Spines     0
Soft-rays   7 - 8
Main Ref. (e.g. 9948)
Glossary ( e.g. cephalopods )
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