Are there any morphological keys for pelagic Lepas of the Northern Pacific?

Mikhail L. Tarbeev

from http://ashipunov.info/shipunov/school/books/biota2006_5.pdf (with pictures)

1(2). Capitulum with 5 well-developed plates .......................................... Lepas (p. 64)

2(1). Capitulum with 2 to 5 vestigial plates ................................ Conchoderma (p. 67)

Genus Lepas Linnaeus, 1767

T y p e s p e c i e s : L. anserifera Linnaeus, 1767.

Capitulum with 5 well-developed plates. Basal part of carina ending in fork, or

rarely rounded. Integument of capitulum thin, without muscles. Mandible with 5-6

teeth. Maxillula with step-shaped front margin having spine-like teeth. Bases of cirri I

with 0 to 6 pairs of filamentary appendages. Caudal appendages one-segmented.

Species of the genus Lepas are passively pelagic, distributed in all the world

oceans except for the Arctic Ocean and high latitudes of the Antarctic. They occur on

floating objects, including algae (Sargassum, etc.) and on some pelagic animals (sea

snakes, fur-seals).

The genus comprises 12 species. Five species from this genus are found in the

Russian waters of the Sea of Japan.

KEY TO THE SPECIES OF THE GENUS LEPAS

1(2). Plates with clear radial striations. Five to six filamentary appendages on each

side of body ...................................................................... 1. L. anserifera (p. 64)

2(1). Plates with weak radial striations. Less than 5 filamentary appendages on each

side of body.

3(6). Carina separated from scutum by comparatively broad gap. Three to four filamentary

appendages on each side of body.

4(5). Both scuta with inner umbonal teeth. Four filamentary appendages on each side

of body ................................................................................. 2. L. gogolevi (p. 65)

5(4). Scuta without umbonal teeth. Three filamentary appendages on each side of body

................................................................................................... 3. L. hillii (p. 65)

6(3). Carina separated from scutum by narrow gap. Less than 3 filamentary appendages

on each side of body.

7(8). Tergum with notch on lower side ................................... 4. L. beringiana (p. 66)

8(7). Tergum without notch on lower side ................................. 5. L. anatifera (p. 66)

1. Lepas anserifera Linnaeus, 1767

(Pl. II, fig. 3)

Linnaeus, 1767: 1109 (Lepas anserifera). Before 1982 see Zevina, 1982: 14, fig. 4;

Zongguo et al., 1986: 110, 113.

Description. Plates of capitulum with clear radial striations and placed close together.

Tergum generally more striated than scutum. In young specimens carina may

have saw-toothed dorsal margin. Waist over fork of carina poorly pronounced. Prongs

of fork diverging at angle of 90º or more; crest between them curved. Internal umbonal

tooth more pronounced on left-hand scutum; that on right-hand scutum, often knob-

like. Umbo-apical ridge of scutum separates relatively broad portion off occludent

margin. Five, rarer six, filamentary appendages on each side of body. Length of capitulum

up to 4 cm, length of peduncle usually equal to capitulum length.

Distribution. L. anserifera is widespread in tropical and subtropical waters. It

can also be carried by driftwood or by ships to comparatively warm boreal and notalian

waters. It was recorded in the ports of Vladivostok and Nakhodka on cargo vessels

which had called at the ports of the Southeast Asia and the Indian Ocean, in the

fouling community Amphibalanus reticulatus+Lepas anatifera (Mikhailov, 1985a). In

Peter the Great Bay it was found on driftwood, apparently transported from the Tsushima

Strait (Kepel, 2002).

Habitat and breeding. This member of the genus Lepas is confined to the

warmest waters, it is found at a narrow temperature range of 24.4-29.4ºC (Zevina,

1971). There are no records for breeding of this species in the Sea of Japan.

2. Lepas gogolevi Memmi, 1982

(Pl. II, fig. 5, 6)

Lepas gogolevi Memmi, 1982b: 1322–1324, fig. 1.

Description. Capitulum broad, triangular. Plates thick, smooth, and white, placed

with relatively broad gaps in between. Tergum in shape of skew quadrangle. Scutum

broad, triangular, with poorly pronounced umbo-apical ridge. Both scuta with inner

umbonal teeth. Carina with smooth dorsal margin, evenly rounded; apex reaching ¾ of

tergal length; basal part ending in fork with prongs set at right angle to axis of carina

and diverging at angle of 130º. Body with 4 filamentary appendages on each side.

Length of capitulum 2.5 cm, length of peduncle 1.5 cm.

Distribution. L. gogolevi was recorded on driftwood in Vostok Bay and on Bolshoi

Pelis Island (Memmi, 1982b).

Habitat and breeding. There are no records for breeding of this species in the

Sea of Japan.

3. Lepas hillii (Leach, 1818)

(Pl. II, fig. 7, 8)

Leach, 1818: 413 (Pentalasmis hillii). Before 1982 see Zevina, 1982: 14–15, fig. 5.

Description. Capitulum flat; angles rounded except for basiscutal one. Plates

smooth, radial striation almost hardly noticeable, with distinct growth lines. Scutum

and tergum placed close together; gap between carina and scutum broad, especially in

lower part. Carina generally flat; base ending in fork somewhat separated from basicarinal

angles of scuta, prongs of fork diverge at approximately right angle. Umbo-apical

ridge of scutum poorly developed; umbonal teeth absent. Tergum broad; basal angle

rounded; carinal margin strongly convex. Three filamentary appendages on each side

of body.

Distribution. L. hillii is distributed in tropical and subtropical waters, but is less

common than L. anatifera and does not penetrate far north. In the Pacific Ocean it

may penetrate as far north as Bering Island. In the Sea of Japan it was found in the

fouling of the fish trawler Aleksandrovsk when the latter was in a dry dock of the Vla-

divostok port, in the community Balanus crenatus+Lepas anatifera (Mikhailov,

1985a). The trawler had previously worked in the South Kuril and North Pacific fishing

grounds (Mikhailov, 1980; Mikhailov, Blinov, 1981).

Habitat and breeding. There are no records for breeding of this species in the

Sea of Japan.

4. Lepas beringiana Pilsbry, 1911

(Pl. II, fig. 4)

Pilsbry, 1911: 70 (Lepas pectinata beringiana); Zevina, 1982: 16, fig. 6g (Lepas (Anatifa)

beringiana).

Description. Capitulum short, greatly expanding downward. Plates smooth, thin,

translucent. Scutal margin of tergum with 2 distinct notches. Scutum with broad lower

part, usually with 2 umbonal teeth, one better and one poorer developed. Carina with

narrow lower part; prongs of fork pointed. Peduncle short. Base of cirri I with 1 filamentary

appendage on one side and inflated on other side. Caudal appendages poorly

pronounced.

Distribution. L. beringiana is distributed in the North-West Pacific near the

Asian coasts north of 36ºN to the Bering Sea. It was found in the Sea of Japan on the

refrigerator trawler Taman when it was in a dry dock of the Sovetskaya Gavan port, in

the fouling community Balanus crenatus+Lepas anatifera. The trawler had previously

worked in the North Pacific fishing ground (Zvyagintsev, Mikhailov, 1978; Mikhailov,

1980; Mikhailov, Blinov, 1981).

Habitat and breeding. This species of the genus Lepas is confined to the coldest

waters, it occurs at a temperature from 9.9 to 15.1 °C (Zevina, 1971). There are no

records for breeding of this species in the Sea of Japan.

5. Lepas anatifera Linnaeus, 1758

(Pl. II, fig. 1, 2)

Linnaeus, 1758: 668 (Lepas anatifera). Before 1982 see Zevina, 1982: 17, fig. 8; Memmi,

1982a: 1165–1168, figs. 1–2.

Description. Plates of capitulum smooth, minutely striated and with distinct

growth lines. Gaps between plates vary in width. Tergum usually with convex, triangle

or skew quadrangle carinal margin; ventral margin strongly curved, often angular.

Scutum triangular, with convex frontal and carinal margins. Umbo-apical ridge weak.

Left-hand scutum with umbonal tooth, that on right-hand scutum sometimes also

present, but smaller. Carina strongly curved in lower part, its apex reaching ¾ of tergal

length; prongs of basal fork of carina close or almost close to margin of scutum,

placed at right or acute angle to axis of carina; crest situated on outside of prongs

curved. Up to 2, sometimes 1 filamentary appendage on each side of body. Length of

capitulum up to 3 cm, length of peduncle up to 60 cm.

Distribution. L. anatifera is widespread in tropical, subtropical and partly in

temperate waters. This species was occasionally recorded off the Spitsbergen and

Murman coast, and it is common near the coasts of Scandinavia. It also regularly occurs

in beach drift on the Commander and Kuril Islands. It dominates in the ocean

fouling communities in many areas of the North-West Pacific and is common in the

fouling of ships plying through the Pacific past the Kuril and Japan Islands (Zevina,

1982). It was recorded in the ports of the Sea of Japan in the fouling of fishing vessels

arrived from the South Kuril, North Kuril, and the North Pacific fishing grounds

(Zvyagintsev, Mikhailov, 1978; Mikhailov, 1980; Mikhailov, Blinov, 1980, 1981), as

well as in the fouling of cargo vessels which had previously worked near the Kurils

(Mikhailov, Blinov, 1980) and at the routes connecting Russian Far East ports and the

ports of the Northern and Southwestern Japan, Vietnam, and Canada (Mikhailov,

1991; Zvyagintsev, 2000). It occurs in different communities dominated by Balanus

crenatus, Semibalanus cariosus, Mytilus edulis, Amphibalanus amphitrite, A. improvisus,

A. eburneus, A. reticulatus, and Conchoderma auritum. It dominates on ships

working in the South Kuril fishing ground, on which it forms a L. anatifera fouling

community with an average biomass of 1.4 kg/m2

(Mikhailov, 1985a). It was recorded

in Peter the Great Bay on driftwood apparently transported from the Tsushima Strait

(Kepel, 2002).

Habitat and breeding. L. anatifera is the most eurythermal species of the lepadids,

it occurs at temperatures from 15.4 to 29.4 °C (Zevina, 1971). There are no

records for breeding of this species in the Sea of Japan.

New Journal, "Integrative Psychological and Behavioral Science" -- do you not know, and have you not seen, this done before?

Would fecal samples stored at -20C for over a year impact metagenomic analysis?

Could you please recommend some good journal that accept very long revie papers (approximately 6000+ words) in neurosurgery, cancer biology ?

Is CD44 degraded in lysosome together with hyaluronan after CD44 mediated endocytosis of hyaluronic acid?

Where to find data on trees in tropical agroforestry?

Is IMPACT FACTOR justified in case of Taxonomy?

Unknown debris sheets observed in cell culture flasks?

How to culture mouse pheochromocytoma cells (MPC)?

I can detect my protein but the encoding DNA sequence has stop codons within. Should I ignore the stop codons?

What is the best temperature to coat an ELISA plate?