Mastigoteuthis famelica (Berry, 1909)

Introduction

M. famelica is one of two common Mastigoteuthis species in the region of the Hawaiian Archipelago.

Diagnosis

A Mastigoteuthis ...

• with large eyelid photophores but no other photophores.
• with protective membrane on tentacular club nearly absent.

Characteristics

1. Tentacles
1. Club with barely detectable protective membranes.
2. Club suckers uniform in size over club until club diameter diminishes near tip where suckers become smaller.
   image info

   Figure. Four views of club of M. familica, preserved, neotype. Left - Oral view in midregion of club. Left middle - Side view in midregion of club at lower magnification. Right middle - Aboral view in midregion of club. The distnctive mantle pigmentation is seen in the background.Right - Oral view of club base. The separate sucker patches on the latter may be an artifact of damage. The tentacle is a bit shriveled from long preservation. Photographs by R. Young.

3. Club suckers slightly elongate, 0.36 mm in length, with 2-3 large, blunt knobs on each side of outer ring that project into aperature. Inner ring with 2 or 3 tiny rounded teeth on distal margin.
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Figure. Oral view of preserved club suckers of M. famelica, neotype.

Scanning electron micrographs of the suckers can be found here.

2. Fins
1. Fins longer than broad.
2. Anterior and posterior fin lobes absent.


3. Photophores
1. Eyelid photophore present; other photophores absent.
image info

Figure. Lateral view of the head of M. famelica showing eye size and size of eyelid photophore (arrow), immature female, 140 mm ML, preserved, Hawaiian waters. The rather large eyelid photophore (ca 2.3% of ML in longest measurement) may be hidden by pigmentation. Photograph by R. Young.

Comments

More details of the description can found here.

M. famelica is very similar to M. atlantica from the central North Pacific in having large eyelid photophores, absence of all other photophores and fins that are slightly longer than wide. These two species clearly differ, however, in the size of the protective membrane on the tentacular clubs (well developed in M. atlantica and nearly absent in M. famelica). The small (37 mm ML, holotype) M. glaukopis from the Indian Ocean as described by Chun (1910) is very similar except for differences in the size and dentition of the club suckers. Since these latter features change with size, we can find no differences that separate M. glaukopis Chun, 1908 and it is probably synonymus with M. atlantica Joubin, 1933 or M. famelica Berry, 1909, but has priority over both. Until larger specimens of M. glaukopis are available from the Indian Ocean, we maintain all three species. We suspect, however, on the basis of the distinct protective membrane on the tentacular club in the illustrations of Chun (1910) that M. glaukopis and M. atlantica may be synonymus.

Nomenclature

The holotype is no longer extant (Sweeney, et al., 1988) and we designate the specimen described here (immature female, 241 mm ML), Museum No.xxx, as the neotype. Nesis (1980) incorrectly synonymized this species (it had been incompletely described at the time as Chiroteuthis famelica) Berry, 1909 with Chiroteuthis (= Asperoteuthis) acanthoderma.

Life History

Two paralarval stages have been described. The slender shape and lobeless fins are easily recognizable by 7 mm ML.

image infoimage info

Figure. Paralarval stages of M. famelica. Left: Ventral (bottom) and dorsal (top) views of 4.8 mm ML paralarva, Hawaiian waters. Drawings from Young (1991). Right: Ventral (bottom)and dorsal (top) views of 6.9 mm ML paralarva, Hawaiian waters. Drawings from Young (1991).The scale bar is l mm. At 7-9 mm ML (essentially drawings above, right): arm III a papilla; mantle very slender; fin length 1/3 of ML without anterior or posterior fin lobes; eye with silvery rostrum projecting ventrally or anteriorly. Funnel organ with tragus and antitragus recognizable at 25 mm ML. Data from Young (1991).

Small multicuspid tubercles on mantle, funnel, head and aboral surface of arms seen in young of 17 - 40 mm ML. Most of the head tubercules are not visible in the photograph at the right but some on the funnel and its enlargement are visible.

image info

Figure. Left - Lateral view of preserved head and funnel of a paralarva of M. famelica, 35 mm ML, Hawaiian waters. Right - enlargement of a portion of the funnel, 35 mm ML, Hawaiian waters. Paralarva stained with methylene blue. Photographs by R. Young.

Distribution

Type locality: Vicinity of Kauai Island, Hawaiian Islands. Known only from the central north Pacific Ocean.

Vertical distribution

According to Young (1978), most specimens captured in his study were taken at depths between 675 and 800 m, both day and night. The two presummed contaminants were taken at 240 m during the day; the previous tow had fished at 700 m and captured three specimens.

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Figure. Vertical distribution chart of M. famelica. Captures were made with both open and opening/closing trawls. Bar - fishing depth-range of opening/closing trawl. Circle - Modal fishing depth for either trawl. Blue-filled circle - Night capture. Yellow-filled circle - Day capture. Unfilled circle - probable contaminant from previous tow. Note the breaks in the x-axis. Chart modified from Young (1978).

References

Nesis, K. N. 1980. Taxonomic position of Chiroteuthis famelica Berry. Bull. Moscow Obslich. Ispyt. Prirody, Section Biology, 85: 59-66. [In Russian]

Sweeney, M.J., C.F.E. Roper, and F.G. Hochberg. 1988. Catalog of the type specimens of Recent Cephalopoda described by S. Stillman Berry. Malacologia, 29(1):7-19.

Young, R. E. 1978. Vertical distribution and photosensitive vesicles of pelagic cephalopods from Hawaiian waters. Fish. Bull., 76: 583-615.