Lampocteis cruentiventer

Lampocteis cruentiventer

Languages: English

Overview

Comprehensive Description

"Lampocteis cruentiventer, which was first collected in 1979 off southern California and later collected and studied in detail from 1991 to 1999 in Monterey Bay. This ctenophore differs from all previously described lobate ctenophores in three major ways:(1) its remarkable stomodaeum surmounted by capacious paragastric canals with diverticula, (2) the unusual notches that almost create a hole through the animal, and (3) the blindly ending meridional canals.  Because of these distinctive features, we feel justified in erecting a new family, the Lampoctenidae, for this species. Several other features (the large pigmented stomodaeum, the large diverticulate paragastric canals and the well-developed, strongly iridescent comb plates) distinguish this species." (Harbison, Matsumoto, Robison, 2001.)

Author(s): Archer, Cameron
Rights holder(s): Archer, Cameron

Description

Diagnostic Description

"Lobate ctenophore with red stomodaeum, expanded in stomodaeal plane and capable of wide expansion in tentacular plane. Body deeply excavated between adjacent subtentacular comb rows at level of infundibulum. Paragastric canals massive, with blindly ending diverticula, which are branched in some MBARI specimens. Tentacular canals arising at infundibulum at junctions of interradial canals. Interradial canals short, branching to form adradial canals. All adradial canals connect with meridional canals at approximately the level of the infundibulum. All meridional canals end blindly at their aboral ends. Auricles fleshy, relatively short and wide, with well differentiated comb plates. Tentacle bulbs large. Well-developed infundibular canal present, about one-third length of stomodaeum. Pole plates narrow and pointed. Oral lobes of moderate size, arising about two-fifths distance between mouth and aboral end of stomodaeum." (Harbison, Matsumoto, Robison 2001.)

Author(s): Archer, Cameron
Rights holder(s): Archer, Cameron

Physiology

"The holotype did not appear to be sexually mature, since no traces of gonads were observed lying along any of the meridional canals. Gonads were not observed on any MBARI specimens.  None were observed with food in their stomachs. No parasitic or commensal organisms were found on them, and no organisms were seen feeding on them."  (Harbison, Matsumoto, Robison, 2001.) 

Author(s): Archer, Cameron
Rights holder(s): Archer, Cameron

Size

"BODY, AURICLES, AND ORAL LOBES.—The body is slightly compressed in the tentacular axis, with the stomodaeal axis about 1.6 times longer than the tentacular axis at the level of the tentacle bulbs. Overall length (tip of oral lobes to aboral pole) of holotype about 5 cm.  The body is raised into 16 slight ridges, when viewed from the aboral pole. The comb plates sit on eight of these ridges, and the other eight ridges lie between the comb rows.  These latter ridges are least pronounced between adjacent subtentacular comb rows, and most pronounced between adjacent substomodaeal comb rows. In addition, the body is excavated between adjacent subtentacular comb rows at the level of the infundibulum, forming a deep notch.  The consistency of the body is extremely firm, and the animal is not completely transparent, so that the internal connections of the gastrovascular system are sometimes difficult to determine. While the body of the holotype was tinted a light red, the color of the body in MBARI specimens ranged from almost transparent to a deep black-purple, with amber and red being the most common tints. The auricles are relatively short and wide, and are extremely fleshy. They appear incapable of much motility. The oral lobes of the holotype were also extremely fleshy and strong, but in larger specimens were much more delicate. The oral lobes are only a little longer than the body. the comb rows lie on eight of the body ridges. The substomodaeal comb rows and the adjacent body ridges are at approximately the same heights, while the subtentacular comb rows lie on higher ridges than the body ridges between them. The substomodaeal comb rows are slightly longer than the subtentacular comb rows. The substomodaeal comb rows end slightly below the auricles, whereas the subtentacular comb rows end slightly above them.  The comb plates are extremely broad and prominent, thus creating a pronounced iridescence, which was so bright that it obscured the details of internal structure in some of the photographs. While the comb rows of most ctenophores have this property, it is more strongly developed in this species than in most others.  The morphology and location of the statocyst is similar to that in other ctenophores.  The pole plates are relatively long, and extended orally to about the level of the sixth substomodaeal comb plate in the holotype.  The pole plates are very slender and pointed,  and lie on the crests of the ridges between adjacent substomodaeal comb rows." (Harbison, Matsumoto, Robison, 2001.)

Author(s): Archer, Cameron
Rights holder(s): Archer, Cameron

References

Harbison, R. C., Matsumato G. I., & Robison B. H. (2001).  LAMPOCTEIS CRUENTIVENTER GEN. NOV., SP. NOV.: A NEW MESOPELAGIC LOBATE CTENOPHORE, REPRESENTING THE TYPE OF A NEW FAMILY (CLASS TENTACULATA, ORDER LOBATA, FAMILY LAMPOCTENIDAE, FAM. NOV.) . Bulletin of Marine Science. 68(2), 299-311.