Table Of Content16
A new genus and species of terrestrial flatworm
from the central highlands of New Caledonia
(Tricladida Terricola)
Leigh WINSOR
James Cook University of North Queensland
Zoology Department
Post Office, James Cook University
Queensland 4811, Australia
ABSTRACT
A new endemic genus and species of terrestrial flatworm, copulatory bursa associatcd with the male copulatory organs.
Pimea monticola is erected and describcd from New Caledonia. Pimea probably differentiated from geoplanid stock with
It is characterized by an antero-ventral adhesive organ, ventral testes, strong cutaneous longitudinal muscles and
specialised insunk ventral culaneous musculature, and a absent parcnchymal longitudinal muscles.
RÉSUMÉ
Description d'un genre et d'une espèce nouveaux, Pimea copulatcurs sont dépourvus d'adénodactyle. Les ovaires sont
monticola, endémique de Nouvelle-Calédonie. Le genre est pourvus de réceptacles séminaux et la bourse copulatrice
caractérisé principalement par la présence d'un organe s'ouvre dans l'atrium mâle. Le pénis possède une papille
adhésif musculo-glandulaire en position antéro-ventrale, intra-péniale. Pimea s'est probablement différencié à partir de
pourvu d'un muscle rétracteur constitué par les fibres Geoplanidac à testicules ventraux, à muscles cutanés longitu¬
musculaires longitudinales sous-épidermiques immergées. Les dinaux forts et dépourvus de muscles parenchymateux longitu¬
testicules et les canaux déférents sont ventraux. Les organes dinaux.
Winsor, L., 1991. A new genus and species of terrestrial flatworm from the central highlands of New Caledonia (Tricladida :
Terricola). In : J. Chazeau & S. Tillier (cds). Zoologia Neocaledonica, Volume 2. Mém. Mus. nain. Hisl. nul.. (A). 149 : 19-30. Paris ISBN :
2-85653-179-2.
Publié le 20 février 1991.
Source : MNHN, Paris
20 LEIGH WINSOR
The terrestrial flatworms of New Caledonia worms were collected from 46 stations in various
and the Loyalty Islands were described by Graff régions of New Caledonia. Ten previously des¬
(1899), Busson (1903) and SCHRÔDER (1923). Of cribed species hâve now been tentatively identi-
the 21 species described, 13 are endemic to New fied, but in addition there are a number of
Caledonia, and comprise 10 species of Geoplana undescribed species. This paper describes a new
(Geoplanidae) and three species of Rhynchode- endemic genus and species from the central
mus (Rhynchodemidae). The original descrip¬ highlands of New Caledonia.
tions included full anatomical accounts for only
two species, Pelmatoplana willeyi Busson, 1903 Materials and methods : collections were made
and Geoplana forsterorum Schrôder, 1923. More monthly from 25 square métré quadrats in the
recently Kawakatsu (1969) reported on the leaf litter at stations in which ail the flora had
copulatory organs of Geoplana cookiana Schrô¬ been inventoried (orstom), and from leaf litter at
der, 1923, a previously described species. numerous stations in various régions of New
In the course of two research projects of the Caledonia (mnhn).
orstom (Institut Français de Recherche Scien¬ The holotype was fixed in the field in 4 %
tifique pour le Développement en Coopération) formaldéhyde solution, and subsequently pro-
(ecology) and Muséum national d'Histoire natu¬ cessed to paraffin wax, sectioned at 7 (xm, and
relle (mnhn) (systematics, phylogeny and bio- stained by the Mallory-Heidf:nhain and other
geography), 107 specimens of terrestrial flat¬ histochemical methods (Winsor, 1983).
Family GEOPLANIDAE Stimpson, 1857
Genus Pimea n. g. situated on the latéral aspect of the ventral nerve
cords ; copulatory organs without adenodactyls.
Type species : Pimea monticola n. sp.
Etymology : the generic name cornes from a Pimea monticola n. sp.
pre-colonial Melanesian clan, the Pime, one of
many clans in the région south-east of the type Holotype : serial sagittal and transverse sec¬
locality. The spécifie epithet is derived from the tions of the anterior, pre-pharyngeal and poste-
Latin mons a mountain and colo to inhabit, and rior régions on a sériés of 21 microslides. The
alludes to the locality in which the species was type, register number uc 95, is lodged in mnhn.
first recorded.
Type locality : a single specimen was collected
Diagnosis : Geoplanidae with elongate body ; at Station 92a in wet forest, 1 000 métrés altitude
creeping sole almost one third of the body on the summit of Mt Aoupinié, 165°I5'52"E,
width ; anterior end expanded ; single glandulo- 21°10'46"S, by P. B. Mordan, A. and S. Til-
muscular organ (adhesive pad) located antero- lif:r, 5th May, 1987.
ventrally ; longitudinal cutaneous musculature
well developed ; muscle bundles smaller dorsally External features : the preserved specimen
than ventrally ; ventral cutaneous longitudinal (figs 1-2) is very small and elongate, measuring
musculature partially insunk into the parenchyma 11 mm by 1.7 mm maximum width (length-width
intemally to the cutaneous nerve net to form the ratio I : 6.5). The ventral mouth is situated
retractor muscle for the glandulo-muscular organ ; 7.2 mm behind the anterior tip and the gonopore
dorsal cutaneous muscles integrated with paren- 1.8 mm behind the mouth. In cross section the
chymal transverse muscles form glandulo-muscu¬ body is convex dorsally, near-flat ventrally.
lar organ extensor muscle ; ventro-lateral sensory The expanded anterior end (head), 1.2 mm
zone restricted to neck, with few small sensory wide and 1.5 mm long, is rounded anterolale-
pits ; testes ventral, uniserial ; vasa deferentia rally. The ventral surface consists of a single
Source : MNHN, Paris
TERRESTRIAL FLATWORM FROM NEW CALEDONIA 21
GM
Figs 1-4. Pimea monlicola n. g. n. sp. 1 : dorsal view of holotype ; 2 : ventral aspect of holotype ; 3 : ventral aspect of the
anterior end ; 4 : a diagramatic représentation of the principal internai structures of the anterior end.
es, crccping sole ; dl. dorsal cutaneous longitudinal muscles ; em, extcnsor muscles ; GM, glandulo-muscular organ ;
gp, gonoporc ; id, intestinal divcrticulum ; le, large eyes ; mo, mouth ; nc, nerve cord : oy, ovary ; rm. retractor
muscles ; se. small eye ; sz, sensory zone ; te, testis ; tm, transverse muscles ; vl, ventral cutaneous longitudinal muscle.
Source : MNHN, Paris
22 LEIGH WINSOR
glandulo-muscular organ, the protubérant pad of There are at least two types of both acidophil
which exhibits a slight médian indentation near and basiphil glands which are particularly nume-
the creeping sole. The periphery of this organ is rous in the mesenchyme. Acidophil glands occur
slightly crenulate. peri-intestinally and are concentratred infra-
Behind the anterior end, the body gradually intestinally. In the anterior third of the body
broadens to maximum width over the pharynx, acidophil sécrétions pass to the anterior end to
then evenly tapers to a rounded end. The serve the glandulo-muscular organ and dorsal
creeping sole is almost a third of the body width epithelium of the head. Strongly basiphil glands
and extends from the posterior tip to the narro- are located peri-intestinally ectally to acidophil
west part of the body immediately behind the glands, and glands situated infra-neurally service
expanded anterior end. the creeping sole. Paler staining basiphil glands
Unpigmented sensory zones lie ventro-laterally are prominent in the dorsal mesenchyme. Histo¬
either side and slightly beyond the creeping sole chemically both types of basiphil glands contain
anteriorly. A single row of ocelli are présent sécrétions of neutral mucin or glycoprotein.
either side of the base of the anterior end and The cutaneous musculature is well developed
extend posteriorly along the ventro-lateral mar- and composed of the usual three sets of muscles :
gin of the body. The eyes are large anteriorly, an outer layer of circular muscles, an inner
decreasing in size posteriorly. Ocelli do not sheath of bundles of longitudinal muscles, both
extend anteriorly beyond the proximal margin of sets separated from each other by a set of
the adhesive pad (fig. 3). decussale helical muscles. The pre-pharyngeal
The dorsal ground colour is a uniform dark région of the body is a maximum of 527 |xm
tan, paler sub-marginally and ventrally to the dorso-ventrally, the dorsal cutaneous muscula¬
inner ventral zone (though the tan colour may be ture 29 [i.m thick and ventral musculature adja¬
a fixation artifact (Winsor, 1983)). The creeping cent to the creeping sole 32 [j.m thick. The
sole is white. cutaneous muscular index (cmi) (Winsor, 1983)
is 11.5%. Laterally the musculature is reduced
Body wall and musculature : the epithelium is as the bundles of longitudinal muscles are smal-
thicker dorsally (20 nm) than ventrally (12.5 |i.m), ler than those of the dorsum and outer ventral
and is separated from the cutaneous musculature zone.
by a fine bi-fibrilar basement membrane, with no Overall the cutaneous longitudinal muscula¬
evidence of pigment granules. Only the creeping ture has smaller bundles dorsally than ventrally.
sole appears ciliated, with cilia 4.3 j/.m long mid Anteriorly the ventral cutaneous longitudinal
ventrally, and is 27 % of the pre-pharyngeal muscles thicken and divide with the major
body width. portion insunk into the parenchyma entally to
Rhabdoids of the rhabdite type, obovate in the cutaneous nerve net. The muscle bundles
shape, are secreted by mesenchymal rhabditogen deepen and form the ventral retractor muscle for
cells. Rhabdites pack the dorso-lateral epithe¬ the glandulo-muscular organ (fig. 4). Posterior to
lium and extend ventrally to the edge of the this division the ventral cutaneous longitudinal
creeping sole. Mid dorsal rhabdites measure muscle bundles are small and poorly defined over
approximately 14 ^m by 4.5 |xm in gréa test width the creeping sole. Individual fibres are scattered
and are slightly larger than those most ventrad and insunk in the parenchyma (fig. 8).
which are approximately 12.5 by 2 |xm wide. Between the cutaneous musculature and the
Histochemically they are composed of basic gut the compact mesenchyme contains numerous
protein. Dorsally and laterally in the anterior collagenous fibres, glands, protonephridia and
portion of the body, the rhabdites are présent in weak parenchymal muscles, principally circulo-
the ephithelium as clusters (fig. 5). oblique fibres. These muscles are most numerous
The dorsal epithelium of the head differs from laterally in the régions where the cutaneous
that elsewhere. There are few rhabdites and musculature is reduced. Strong dorso-ventral
micro-rhabdites. The epithelium is strongly aci- muscles lie between the intestinal diverticula.
dophilic from the presence of fine grained sécré¬ Prominent transverse muscles underlie the
tions and larger spherical bodies derived from cutaneous musculature dorsally, and anteriorly
glands between the dorso-ventral muscle fibres. with dorso-ventral muscles and insunk éléments
Source : MNHN, Paris
TERRHSTRIAL FLATWORM FROM NEW CALEDONIA 23
of the dorsal cutaneous longitudinal muscles, lie between the muscle fibres deep within the
develop into a thick compact infra-intestinal organ. Their fine granular sécrétions, histochemi¬
plate, the extensor muscle of the glandulo-mus- cally neutral mucins or glycoprotein, pass to the
cular organ. surface via long ducts which spiral up the
In the mid-parenchyma of the head the ventral muscular columns to the micro-pads. These
retractor muscle and the extensor muscle meet sécrétions may include a releasor substance.
and interdigitate through interstices in the neural
tissue to form a dense muscular cephalic plate Alimentary System : the intestine is the usual
(fig. 4). From the plate thick fibres pass dorsally triclad type with a single anterior ramus and two
to the head, and ventrally to serve the glandulo- posterior rami diverging from the pharyngo-
muscular organ. intestinal junction. There are approximately five
intestinal branches per millimétré of body length.
Glandulo-muscular organ and associated struc¬ Each branch terminâtes in a not deeply divided
tures : the glandulo-muscular organ consists of a lobulate diverticulum. Small diverticula termi-
single ovate pad separated from the adjacent nate about 430 jj.m from the anterior tip of the
body by a narrow peripheral grove. There is no head and overlie the extensor muscle. In this
médian sulcus, and the creeping sole terminâtes specimen the gut is empty and gastrodermis
well before the pad. inactive.
Two types of closely associated mucus glands The pharynx is cylindrical, 250 ii.m long, and
open from the ectal margin of the groove which almost horizontal in attitude. The dorsal inser¬
séparâtes the organ from the adjacent epithelium tion of the pharynx is posterior to the ventral
(fig. 5). They are conspicuous basiphilic gland insertion. The outer epithelium is ciliated and
with granules of neutral mucin-glycoprotein, and infra-nucleate, underlain by a layer of circular
the weakly basiphilic acid mucopolysaccharide muscles and a layer of longitudinal muscles. The
secreting glands. central portion of the pharyngeal wall contains
The glandulo-muscular organ is composed ducts of basiphilic glands ectally, and those of
of numerous micro-pads on muscular columns acidophilic glands entally. The glandular areas
between which sécrétions pass to the surface. are traversed by radial and circular muscle fibres.
Large bundles of muscle fibres, principally deri- The lumen is lined by a ciliated infra-nucleate
ved from the ventral retractor, extend from the epithelium underlain by a layer of mixed circular
plate to the organ. Some 50-60 ixm from the and longitudinal muscles in basiphilic mesen-
surface these muscles extensively ramify and in chyme.
small bundles of two or three fibres develop a The pharyngeal pouch is 280 um long (2.5 %
right-handed spiral, terminating at the micro- of the body length), and is mostly lined by a
pads. These structures (fig. 6) are 20 fi.m long and flattened epithelium underlain by layers of circular
are enlarged where the muscles attach to the then longitudinal muscles. A small diverticulum
basement membrane. They narrow to a nucleate occurs in the mid posterior wall of the pouch.
acidophilic epithelium bearing what appears to
be compact modified cilia 2.8-3.6 (im long. Excretory System : protonephridia are présent
Four types of sécrétions are associated with in the peri-intestinal mesenchyme, though they
the glandulo-muscular organ. Copious coarse are not abundant and do not appear highly
granules up to 8 ^m of basic protein sécrétions, developed. End canals contain three or four
derived from mesenchymal glands deep within flame cells, each 4-5 txm long and 1 jxm diameter
the parenchyma, pass to the surface between the with a single flagellum and terminal nucléus.
columns of micro-pads and at the margins of the Ciliated convoluted tubules, final duct and exil
organ. At the surface they coalesce, presumably canal are présent, but could not be followed
forming an adhesive. Very weakly basiphilic, through the sections for any great distance.
almost chromophobic mucoid sécrétions from me¬
senchymal glands also pass to the surface between Sensory organs : approximately 12-13 sensory
the basic protein granules and muscular stalks. pits spaced about 70 ij.m apart are situated in
Histochemically these sécrétions are acid muco- each of the unpigmented sensorial zones either
polysaccharides. Basiphilic and acidophilic glands side of the anterior creeping sole. The pits are
Source : MNHN, Paris
24 LEIGH WINSOR
500 (jm
Figs 5-8. Pimea monticola n. g. n. sp. 5 : diagramatic représentation of lhe celai margin of the groove surrounding lhe
glandulo-muscular organ ; 6 : diagramatic représentation of the structure of the glandulo-muscular organ ;
7 : diagramatic représentation of lhe right ovary (inset : right ovary showing séminal réceptacle, unscalcd);
8 : diagramatic représentation of the pre-pharyngeal (posteriad) transverse section.
ag. acidophil gland ; bg. basiphil gland : bp, basic protein sécrétion : es, creeping sole ; dn, dorsal nerve : i»v. dorso-
vcntral muscles ; il, insunk cutaneous longitudinal muscles ; mp. micro-pads of glandulo-muscular organ : \tx. compact
basiphilic mesenchyme ; nc. nerve cord ; ns, nurse cells ; oc, oocyte ; ov, ovovitelline duel ; rc, rhabditc cluster ; km.
retractor muscles ; sp, sperm ; sr, séminal réceptacle ; n:, testis ; tm, transverse muscles ; vu, vas déferons ; vi, vitcllaria.
Source : MNHN, Paris
TERRESTRIAL FLATWORM FROM NEW CALEDONIA 25
ciliated and shallow, measuring 14.2 [xm long, The copulatory organs (figs 9-11) lie immedia¬
3.5 jxm wide, with lumen 10.7 [xm deep and tely behind the pharyngeal pouch, surrounded by
3.5 [xm diameter. a thinly muscularised highly glandular stroma.
Ocelli are of the pigment-cup type and 14- The gonopore communicates with the atria via a
118 [xm diameter. The largest eyes occur ante- 35 |xm diameter foramen in the inter-atrial trans¬
riorly, eye size diminishing as the ocelli pass verse septum. A copulatory bursa opens into the
caudally. Anteriorly the ocelli are about 80 |xm anterior upper quadrant of the male atrium just
apart with 18-30 retinal rods each. to the right of the midline. Ejaculate is contained
within the bursa and male atrium. Atrial muscu¬
Nervous System : paired nerve cords 70 |xm lature comprises inner circular and outer longitu¬
diameter pass anteriorly and thicken to 100 jxm dinal muscles with bundles of circular muscles
diameter at approximately the same point that présent in the parenchyma below the atrial floor
the retractor and extensor muscles arise. Proxi- surrounding the entai opening of the gonopore.
mally to the cephalic muscular plate the cords Male organs. Throughout the pénis, the course
thin, unité and expand laterally. The nerve tissue of the efferent duct is tortuous. The spermiducal
is perforated by dorso-ventral muscle and glands. vesicles, séminal vesicle, prostate, ejaculatory
Posteriorly, extensive transverse commisures link duct and penial duct are ail individually circum-
the nerve cords. The cutaneous nerve net is scribed by a thin tunica, and clearly differentiated
prominent dorsally. from each other by spécifie cell types and modes
of glandular sécrétion.
Reproductive System : the two ovaries are The vasa deferentia curve mediad, distend,
situated 1.7 mm from the anterior tip, slightly and unité in the mid body. Dorsal to this
embedded in the superior surface of the ventral common sperm duct the vasa deferentia form
nerve cords (fig. 4). Each ovary (fig. 7) measures large paired spermiducal vesicles. The common
170 |xm dorso-ventrally, 100 [xm antero-poste- sperm duct proceeds to the séminal vesicle, lined
riorly and 200 |xm medio-laterally, with a promi¬ by a tall, non-ciliated columnar epithelium packed
nent séminal réceptacle, 50 jxm in diameter, pro- with coarse secretory granules. Most of the
truding from the mesiad side. The ovovitelline sécrétions are acidophilic, some basiphilic, ail
duct emerges from the ventral aspect of the secreted in a holocrine manner. Sperm are
junction between the body of the ovary and the présent in the lumen.
séminal réceptacle, and passes posteriorly along The séminal vesicle leads to the prostate which
the superior margin of the nerve cord. surrounds the duct lined by tall ciliated colum¬
Both ovaries contain maturing oocytes sur- nar cells through which fine acidophilic and ba¬
rounded by nurse cells, and mature oocytes. The siphilic granules are secreted directly into the
séminal réceptacle is lined by a tall columnar lumen. The prostatic tissue is composed of
epithelium with basal nuclei, and (illed with mostly strongly basiphilic intra-mural glands
tightly packed spermatozoa. between which pass sécrétions of extra-mural
Vitellaria (fig. 8) lie in the parenchyma be¬ acidophil glands.
tween the intestinal diverticula and pass their Continuous with the prostate is the ejaculatory
sécrétions via short vitelline funnels to the duct, lined by a non-ciliated, infra-nucleate co¬
ovovitelline duct. lumnar epithelium. Through the epithelium intra-
Numerous mature testes (18-20 per mm body mural acidophil glands pass granules which are
length) lie in uniserially-staggered row between secreted into the lumen in an apocrine manner.
the intestinal diverticula, along the superior side The ejaculatory duct terminâtes in an intra-
of the ventral nerve cords (fig. 4). They extend penial papilla protruding into the capacious
from just behind the ovaries to immediately proximal penial duct. This duct extends and
anterior to the pharynx. Each testis is roughly expands laterally behind the bursa and is lined
ellipsoidal, 180 jxm dorso-ventrally and 50 am by a low columnar epithelium with a brush
diameter with a testicular funnel emerging laterally border, suggesting an absorptive function.
from the lower testicular pôle to join the vas The penial duct communicates with the male
deferens passing along the latéral margin of the atrium via the penial sheath, a weakly muscu-
ventral nerve cord (fig. 8). larized passage lined by a ciliated epithelium.
Source : MNHN, Paris
26 LEIGH WINSOR
Fig. 9. — Pimea monticola n. g. n. sp. Diagramalic mid-sagittal composilc reconstruction through the copulatory organs.
Note that the copulatory bursa (indicated by a broken line) is not a midline structure. For clarity, the cjaculatc présent
in the bursa and male atrium has not been shown.
cb. copulatory bursa ; co, common ovovitclline duct ; cv, common sperm duel : ED, cjaeulatory duel ; gc, glandular
canal ; gp. gonoporc ; IP. intra-pcnial papilla ; ov, ovovitclline duel ; pd. pcnial duct ; pg. prostate gland : ps. penial
sheath ; so, spermiducal vesicle ; sg, shcll glands ; sv. séminal vesicle ; ts, transverse inter-atrial septum ; vd, vas
deferens.
The sheath terminâtes in a ventral tongue-like by a rugose, basiphilic, tall columnar epithelium.
flap which protrudes into the atrium. The pos- Acidophilic granules pass through the epithelium
terior third of the male atrium is ciliated. with to the lumen.
a flattened nucleate epithelium lining the re- The copulatory bursa (fig. 10) is spheroidal,
mainder. and approximately 200 jim diameter and is situated
Penial musculature comprises circular muscles on the right of the body. admedially abutting the
surrounding the duct. In the séminal vesicle the musculature of the pénis sheath. A highly glan¬
circular muscles are widely spaced, in the pros¬ dular stroma, weakly muscularised by interwoven
tate they are more tightly packed, and in the longitudinal and oblique fibres, surrounds the
cjaeulatory duct arranged in tightly packed bundles bursa. Within the stroma are extensive sinuses
each of approximately three muscle fibres. Glan¬ containing amorphous basiphilic sécrétions of
dular areas are lightly muscularised by sparse neutral mucin or glycoprotein. The bursal epithe¬
longitudinal-oblique fibres. Strong retractor lium is difficult to discern because of abundant
muscles surround the penial duct and are présent sécrétions surrounding the ejaculate présent in
within the inter-atrial septum. the lumen.
Female organs. The ovovitelline ducts pass The ejaculate is approximately 500 [j.m long
behind the copulatory organs before they incurve and shaped like an elongate tear. with the broad
and unité to form the common ovovitelline duct. end mostly within the bursa and narrow end
The common duct ascends dorsad curving ante- occupying much of the male atrium. The ejacu¬
riorly to join the glandular canal which receives late consists of an inner core of sperm mixed
sécrétions from adjacent shell glands. The glan¬ together with large acidophilic droplets similar to
dular duct opens into a small female atrium lined those of the séminal vesicle. Surrounding the
Source : MNHN, Paris
TERRESTRIAL FLATWORM FROM NEW CALEDONIA 27
10
500 pm
FlGS 10-11. Punea monticola n. g. n. sp.. copulatory organs. 10 : longitudinal latéral section illustrating thc latéral aspect of
tne pcntal duel, the copulatory bursa and ejaculate ; 11 : mediad longitudinal section.
ed, ejaculatory duct ; FJ, ejaculate ; fa. female atrium ; gc, glandular canal : GP, gonopore ; ma. male atrium : PD.
penial duct : PG, prostate giand ; ph, pharyngeal pouch ; sv, séminal vesicle ; ts. transverse inter-atrial septum.
core is an inner amorphous layer of strongly tions appearing coagulated and totally enclosing
acidophilic sécrétion, a layer of basiphilic mate- the sperm mass.
rial, and an outer layer of a strongly basiphilic
substance with attached acidophilic droplets. Pathology : a small larval nematode is présent
Layering within the ejaculate reflects the sequence in the infraneural parenchyma over the creeping
of sécrétions within the pénis, the outer sécré¬ sole. There is no evidence of tissue reaction.
Source : MNHN, Paris
28 LEIGH WINSOR
Discussion
Recent authorities, for example Cannon (1986), sive pads, dorsal testes, and retractor muscle
use the following characters to distinguish between formed from insunk éléments of the cutaneous
families in the Terricola : number, size and longitudinal musculature. The eyes in this genus
distribution of eyes ; shape of the anterior end ; do not pass around the anterior tip, but are
extern of the sensory groove ; width and extent restricted to the sides of the anterior end. The
of the creeping sole ; general body shape ; élabo¬ sensorial zones are présent within the pad on
rations of the head ; and complexity of the either side of the anterior tip. Adenodactyls are
copulatory organs particularly the presence or absent from the copulatory organs.
absence of a bursa and genito-intestinal canal. Coleocephalus from Auckland Island, New
Pimea monticola n. g. n. sp. has large multiple Zealand. has a single hooded (cotyloplanid-type)
eyes laterally which extend only part way along adhesive pad, and dorsal testes. The eyes pass
the sides of the head ; an expanded anterior end, around the anterior tip. Adenodactyls are pré¬
not sharply defined at the neck, with an antero- sent in the copulatory organs. The musculature
ventral glandulo-muscular organ ; few sensory and sensorial zone of this genus hâve yet to be
pits in small sensory grooves parallel to the long described (Winsor, redescription in prep.).
straight-pointed beginning of the creeping sole ; It is concludcd thaï the combination of cha¬
creeping sole fiat and almost one third of body racters exhibited in Pimea monticola from New
width ; body robust with low length-width ratio ; Caledonia precludes it from being accommodat-
and complex copulatory organs with accessory ed in existing geoplanid généra, and it is there-
glands and bursa. These characters largely accord fore placed in a new genus Pimea.
with those of the family Geoplanidae to which Longitudinal parenchymal musculature derived
the species is assigned. from cutaneous longitudinal muscles insunk in-
Within the Geoplanidae the principal characters ternally to the cutaneous nerve net is found in
used to distinguish généra include : specialization Choeradoplana. Pimea and two Chilean généra
of the anterior end ; whether the testes are of Froehlich (1978), Gusana and Liana without
dorsally or ventrally situated ; position of the glandulomuscular organs.
male efferent System with respect to the ventral The cutaneous and parenchymal longitudinal
nerve plate ; and musculature with particular musculature, and the arrangement of the ocelli of
emphasis upon the cutaneous and parenchymal Pimea is closest to that of Choeradoplana. The
longitudinal muscles. Pimea monticola has a cutaneous musculature of Pimea is weaker than
single antero-ventral glandulo-muscular organ ; that of Choeradoplana and also lacks the strong
ventral testes ; male efferent System placed ventro- transverse supra- and infra-intestinal parenchy¬
laterally on the nerve cords ; and specialized mal muscles présent in some choeradoplanids. In
longitudinal parenchymal musculature, derived Pimea. ocelli do not pass around the anterior tip
from insunk cutaneous longitudinal muscles, but terminate part way along the head as in
serving the adhesive pad. Choeradoplana.
Three geoplanid généra hâve glandulo-mus¬ Distinctive features of Pimea monticola are the
cular organs ; two Neotropical généra, Issoca presence of séminal réceptacles in the ovaries,
Froehlich, 1955 and Choeradoplana Graff, 1890, and a copulatory bursa. The copulatory bursa is
and the Notogaeic Coleocephalus Fyfe, 1953. particularly unusual as it opens anteriorly from
Issoca has a single antero-ventral adhesive pad, the male atrium and isclosely associated with the
dorsal testes, and retractor muscle formed by the pénis. Within the Geoplanidae bursae are usually
cutaneous longitudinal musculature which is not associated with the female atrium and copulatory
insunk. The eyes and sensorial zone pass around organs. The composition and structure of the
the ventro-lateral margin of the anterior tip. ejaculate in P. monticola is more complex and
Adenodactyls are absent from the copulatory multilayered than normally observed in terricolan
organs. ejaculates, and may be more appropriately termed
Choeradoplana has paired antero-ventral adhe¬ a spermatophore.
Source : MNHN, Paris
