New species and records of Amakusanthura, Cyathura and Haliophasma from Sri Lanka (Crustacea: Isopoda: Anthuridae)

34 Pages·1991·13.4 MB·English

by  H-G Muller

Revue suisseZool. Tome98 Fase. 3 p. 589-612 Genève, septembre 1991
New
species and records of Amakusanthura,
Cyathura and Haliophasma
from Sri Lanka
(Crustacea: Isopoda: Anthuridae)
by
Hans-GeorgMÜLLER *
with 101 Figures
Abstract
New species and records are presented for the isopod family Anthuridae from a
sabellariid reef at the west coast of Sri Lanka. Amakusanthura moragallae n.sp.,
Amakusanthura stocki n.sp. and Cyathura bentotae n.sp. are described. Haliophasma
pooreiKensley, 1980 isredescribed, withconsiderationofthemale unknownuptonow.
INTRODUCTION
This paperis partofa series dealing with shallow watercrustaceans fromthe tropical
Atlantic andIndopacific Ocean. Itreports onanthuridisopods from asabellariidreefatthe
westcoastofSriLanka.
The genera Amakusanthura, Cyathura and Haliophasma are represented with 4
species, 3 ofthese being new to science. Haliophasma poorei Kensley, 1980, previously
known from off Somalia and off Bombai, India, requires a complete redescription, with
consideration ofthe 6 unknownuptonow.
The area investigated is about 1 km north of the mouth of the Bentota river, very
close to the Moragalla and Beruwala villages. Therefore this location is under some
freshwaterinfluence on themarine organisms, particularly during the monsoon season.
Specimens have been collected by the author over a period of2 weeks in May 1989.
particularly from the moreexposedouterreefflatandthe sheltered innerreefedge.
* InstitutfürAllgemeine und Spezielle Zoologie derJustus-Liebig-Universität, Heinrich-Buff-
Ring29,D-6300Giessen,Germany(presentaddress).
* Laboratoire de Biologie Marine et de Malacologie, Université de Perpignan, Avenue de
Villeneuve,F-66025PerpignanCedex,France.
.
590 HANS-GEORGMULLER
Specimens are deposited in the Muséum d'Histoire naturelle, Genève (MHNG) and
theMuséumnationald'Histoirenaturelle, Paris (MNHN).
Figs 1-8.
Amakusanthura moragallae n.sp., immature adult, holotype: 1) dorsal view; 2) telson; 3) antenna 1;
4)antenna2;5)mandible;6)maxilla;7)maxilliped; 8)pleopod 1
,
ANTHURIDAEFROM SRI LANKA 591
AmakusanthuraNunomura, 1977
Amakusanthura moragallaen.sp. (Figs. 1-29)
Holotype: Immature adult (MHNG); outer reefflat, from sabellariid colonies, intertidal, 8-16
May 1989.
Paratypes: 2 S, 6 immature adults, depositedasfollows: 1 <?,4 immature adults MHNG; 1 6
2immatureadultsMNHN; collectedtogetherwithholotype.
Derivatio nominis: The specific name refers to the village Moragalla, which is very
closetothetypelocality.
Description, immature adult: Body relatively slender, 11.6 times longer than wide,
bearing some lateral setae. Total length 2.4-7.1 mm. Cephalon with rather small, well
pigmented anterolateral eyes. Cephalon, pereonites and posterior part ofpleon with some
dorsal irregular pigment reticulations. Body proportions: C<1<2 = 3=4 = 5 = 6>7.
Pleonites 1-3 free, pleonites 4 and 5 fused dorsally. Telson tongue-shaped, widest about at
midlength, 1.9 times longer than wide and distally rounded; telsonic margin in distal half
faintly serrate and bearing many setules; dorsal surface oftelson in distal halfwith 3 pairs
ofsetaein arrangementas figured; distalmarginoftelson also with 3 pairs ofsetae.
Antenna 1, peduncle 3-articulated; proximal article widest and 1.7 times length of
second article; third article slightly longer and narrower than second article, bearing long
seta at outer distal margin; flagellum of 3 articles, with second article longest; terminal
article smallest, bearing 5 simple setae and 2 aesthetascs. Antenna 2 relatively robust;
peduncle of5 articles, second largest, grooved to accomodate peduncle of antenna 1; 4th
peduncular article 1.75 times length of third article; 5th article 1.3 times longer than 4th
article; flagellum of 4 setose articles, proximal article as long as three distal articles
together. Incisor of mandible with 3 cusps, lamina dentata with 5 marginal serrations;
mandibular palp of3 articles, with second article longest; first and second article bearing
short distal seta; terminal article smallest, bearing 4 short fringed setae. Maxilla elongate,
mediallycurvedindistalthird; distalpart5-toothed, bearing minute setabetweenthird and
fourth indentation. Maxilliped robust; endite roughly triangular, tipped with short seta
which extends beyond distal margin of first palp article; palp of 3 articles, terminal one
being smallest, articulating at outerdistal margin ofsecond article; distal article bearing 4
medially curved setae. Pereopod 1 robust, subchelate; propodus expanded, roughly oval in
outline; palm nearly straight, with 4 simple setae and row of5 scales; mesial surface near
palm bearing 5 simple setae; carpus elongate triangular, with 2 posterodistal setae.
Pereopods 2-7 ambulatory, similar to each others, each article bearing some setae;
propodus roughly rectangular, posterodistal margin always with denticulate compound
spine (pereopod 7, 3 compound spines); posterior margin ofpropodus in pereopod 7 with
row of scales in two distal thirds; carpus triangular, lacking free anterior margin in
pereopods 2-3; posterodistal margin of carpus in pereopods 4-7 with small compound
spine. Pleopod 1, sympodite with 3 retinaculae; endopodite narrow, 3/5 length of
operculiform exopodite; endopodite with 2, exopodite with 15 distal plumose setae.
Uropodal sympodite subequal in length to oval endopodite; endopodite bearing several
long setae at outer and distal margin; dorsal surface ofendopodite near outer margin with
8 feathered sensory setae; endopodite slightly extending beyond distal margin of telson;
exopodite slightly longer than endopodite, oval, distal margin with 5 plumose and 9
simple setae.
6: More slender than immature adult (13 times longer than wide) and eyes about
twiceas large. Total length 5.7 mm.
592 HANS-GEORGMULLER
Figs9-17.
Amakusanthura moragallae n.sp., immature adult, holotype: 9) pereopod 1; 10) pereopod 2; 11)
pereopod 3; 12) pereopod 4; 13) pereopod 5; 14) pereopod 6; 15) pereopod 7; 16) uropodal
sympoditeandendopodite; 17)uropodalexopodite.
ANTHURIDAEFROMSRI LANKA 593
Figs 18-26.
Amakusanthuramoragallaen.sp., 8,paratype: 18)dorsalview; 19)antenna 1; 20)antenna2;
21)pereopod 1; 22)pereopod2; 23)pereopod3; 24)pereopod4; 25)pereopod5; 26)pereopod6.
594 HANS-GEORGMÜLLER
100
pm
Figs27-29.
Amakusanthuramoragallaen.sp., a,paratype: 27)pereopod7; 28)pleopod 1; 29)pleopod2.
Antennae more slender than in immature adult. Antenna 1, flagellum of 5 articles;
articles 2-5 decreasing in size distally; article 2 bearing 7, article 3 with 6 and article 4
with 2 aesthetascs; terminal article minute, with few simple setae. Antenna 2, second and
fifth pedunculararticle subequal in length, second article groovedto accomodate peduncle
of antenna 1; flagellum of 4 setose articles, more slender than in immature adult.
Pereopods generally more slender than in immature adult. Pereopod 1 subchelate,
propodus expanded, elongate-oval; mesial surface ofpropodus near palm with 16 curved
setae. Pereopods 2-7, in setation and spination similar to immature adult. Pleopod 1,
sympodite with 4 retinaculae; endopodite slender, 7/10 length ofoperculiform exopodite;
endopodite distally with 6, exopodite with 15 plumose setae (drawn as simple setae).
Pleopod 2, sympodite with 2 retinaculae; rami subequal in length, endopodite narrower;
appendix masculina of endopodite articulating at about midlength, apically rounded,
nearly reaching to distal margin of ramus; endopodite with 3, exopodite with 9 distal
plumose setae (drawn as simple setae).
Manca: Inhabitus similarto immature adult, total length 1.35 mm.
Distribution: SriLanka.
Remarks: I see no close affinities to other members ofthe genus whose descriptions
aregenerallytoo short.
The faintly serrate telsonwith its characteristic arrangementofsetae andtherathersmall,
sparsely setoseuropodalexopodite arereliablefeaturesfortherecognitionofthis species.
ANTHURIDAEFROMSRILANKA 595
Because A. moragallae n.sp. was exclusively found associated with sabellariid
colonies, itis supposedthatitlives inworm tubes.
Amakusanthurastocki n.sp. (Figs. 30-56)
Holotype: Immature adult (MHNG); innerreefedge, from dead barnacles covered with algae,
intertidal, 14May 1989).
Paratypes: 2immatureadults (MNHN);reefflat, frombrownalgae, intertidal andshallowrock
pools,4-16May 1989. 1 S, 1 immatureadult(MHNG); outerreefedge,frombarnacles,intertidal,7-
16 May 1989. 1 a, 3 immature adults, 3 postmancas (MHNG); outer reef flat, from sabellariid
colonies,intertidal,8-16May 1989.
Derivatio nominis: The species is dedicated to Prof. Dr. J.H. Stock, Zoologisch
Museum, Amsterdam, in appreciation for his extensive work on pycnogonids, copepods
andperacaridcrustaceans.
Description, immature adult: Body relatively slender, about 10 times longer than
wide, bearing few lateral setae. Total length 3.8-4.5 mm. Cephalon with rather small, well
pigmented anterolateral eyes. Cephalon with dorsomedian dentritic pigment patch.
Pereonites, pleonites and telson with some dorsal irregular pigment reticulations. Body
proportions: C<1<2>3<4 = 5>6>7. Pleonites 1-3 free, pleonites 4 and 5 fused
dorsally. Telson oval, tongue-shaped, widest at about midlength, 1.7 times longer than
wide and distally rounded; telsonic margin in distal half shallowly serrate and entire
margin bearing many short setules; dorsal surface of telson in distal half with 6 pairs of
setae, the more medially articulating pair much longer than others, as figured; distal
marginoftelsonwith5 pairs ofsetae.
Antenna 1, peduncle 3-articulated; proximal article about as long as article 2 and 3
together; flagellum of3 articles, with second article longest; small terminal article bearing
4 simple setae and 2 aesthetascs. Antenna 2 relatively robust; peduncle 5-articulated;
second article largest, grooved to accomodate peduncle of antenna 1; articles 3-5
increasing in length distally, articles 3 and 4 shallowly grooved; flagellum of 4 setose
articles, proximal article longer than 3 distal articles together. Incisor ofmandible with 3
cusps, lamina dentata with 5 marginal serrations; mandibular palp of 3 articles, with
second article longest; first article with one, second article with 2 simple setae; terminal
article smallest, bearing 4 short fringed setae. Maxilla elongate, medially curved in distal
fourth; distal part 5-toothed. Maxilliped with triangular endite tipped with short simple
seta, seta not reaching to distal margin offirst palp article; palp of3 articles, terminal one
being smallest andbearing 5 medially curved simple setae. Pereopod 1 robust, subchelate;
propodus expanded, roughly oval in outline; palm about at midlength with distinct
rounded tubercle bearing fringe of scales and some short setae; mesial surface near palm
bearing 6 curved simple setae; carpus elongate triangular, posterodistal margin with some
tiny tubercles. Pereopods 2-7 ambulatory, similartoeach others, each article bearing some
setae; propodus roughly rectangular, posterodistal margin always with compound spine,
partly denticulate; posterior margin ofpropodus in pereopod 7 with row of scales in two
distal thirds; anterior and posterior margin ofdactylus in pereopod 7 also bearing row of
scales; carpus triangular, lacking free anterior margin in pereopods 2-3; posterodistal
margin ofcarpus inpereopods 4-7 with small compound spine. Pleopod 1, sympodite with
4 retinaculae; endopodite narrow, 4/5 length of operculiform exopodite; endopodite with
5, exopodite with about 38 distal plumose setae (drawn as simple setae). Uropodal
sympodite 1.3 times length of endopodite; endopodite oval, bearing many long setae at
596 HANS-GEORGMULLER
Figs30-36.
Amakusanthura stocki n.sp., immature adult, holotype: 30) dorsal view; 31) telson; 32) antenna 1;
33)antenna2; 34)mandible; 35)maxilla; 36)maxilliped.
ANTHURIDAEFROM SRI LANKA 597
Figs37-43.
Amakusanthurastockin.sp.,immatureadult,holotype: 37)pereopod 1; 38)pereopod2; 39)pereopod
3;40)pereopod4;41)pereopod6;42)pereopod7; 43)pleopod 1.
outer and distal margin; dorsal surface ofendopodite near outer margin with 8 feathered
sensory setae; endopoditejust extending to distal margin of telson; exopodite larger than
endopodite, roughly oval, with shallow distal notch; exopodite with many plumose and
some simple marginal setae (plumose setae drawn as simple setae, simple setae indicated
with arrow).
6: More slender than immature adult (11 times longer than wide), with eyes greatly
enlarged. Total length 4.0 mm. Cephalon with anteriorly directed, rounded tubercle
anteriortoventral articulation ofmaxilliped.
Antenna 1, penduncle similar to immature adult; flagellum 6-articulated; articles 2-5
with several aesthetascs at outer distal margin; terminal article minute, bearing 2 simple
setae. Antenna 2, peduncle and first flagellar article more slender than in immature adult.
Pereopod 1 similar in outline to immature adult; mesial surface of propodus near palm
HANS-GEORGMÜLLER
598
Figs44-48.
Amakusanthura stocki n.sp., immature adult, holotype: 44) uropodal sympodite and endopodite; 45)
uropodalexopodite. S paratype:46)dorsalview;47)cephalonlateralview;48)distalpartoftelson.
,