Larvae Information Summary for
Protomyctophum thompsoni
| Main Ref: | Moser, H.G. and E.H. Ahlstrom 1996 | |||
Yolk-sac larvae
| min | max | mod | Ref. | |
| Length at birth (mm) | 2.8 | |||
| Preanal L. % TL | 33 | 48 |
| Place of development | planktonic | |||
| Larval area | Northeastern Pacific (California Current region); Northwestern Pacific (Japan) | |||
| Yolk-sac | Ref: | |||
| Yolk | Oil globules | |||
| Rows on tail | ||||
| Other melanophores on tail | ||||
Post larvae
| Striking feature | light organs | |||
| Striking shape lateral | normal (not striking) | dorsal | ||
| Striking feature | light organs | |||
| Shape of gut | elongated | |||
| Gas bladder early | late | pigmented | ||
| Spinal armature early | no spines | late | no spines | |
| Pigmentation early | ||||
| Rows on tail | no rows | |||
| Other melanophores on tail | no other melanophores | |||
| Melanophores on head + trunk | melanophores on trunk | |||
| Pigmentation late | ||||
| Rows on tail | lateral row | |||
| Other melanophores on tail | no other melanophores | |||
| Melanophores on head + trunk | melanophores on trunk | |||
| Urostyle region early | unpigmented | late | unpigmented | |
| Pectorals | normal without melanophores | |||
| Pelvics | fin rays only without melanophores | |||
| Morphology similar to P. crockeri but pigmentation different; postanal series present (absent in P. crockeri); 1-3 lateral gut melanophores (no more than 1 in P. crockeri); Br2 photophores appear at about 8.5 mm; PO series and upper OP photophores the first to form at transformation. Pigmentation: Preflexion: 10-14 in median ventral postanal series. Flexion: postanal series coalesced to 6-11; 1-3 laterally on foregut. Postflexion: postanal series reduced from a maximum of 9 at beginning of postflexion stage to none by 17.0 mm; above gas bladder by about 13.0 mm; beginning at about 13.5 mm, 1-4 embedded in vertical series in lateral hypural region. Sequence of fin development: caudal, pectorals, anal, dorsal and pelvics. | ||||
Meristic characters
| min | max | mod | Ref. | |
| Total number of vertebrae | 37 | 39 | 31442 |
| L 1st feeding | Ref. | Months of presence of larvae | ||||
| max | Jan | Feb | Mar | Apr | ||
| min | May | Jun | Jul | Aug | ||
| mod | Sep | Oct | Nov | Dec | ||
| Water parameters Metric characters |