Geoff and others,
Your NZ North Island worm most certainly is Branchiura sowerbyi Beddard,
1892 (family Tubificidae), a widely distributed species with its possible
origin in Asia. However, your specimen is probably a juvenile; adult
individuals are said to grow to between 40 and 185 mm (with 74 to 270
segments)!
Christer Erséus
Prof. Christer Erséus
Department of Zoology
Göteborg University
Box 463
SE-405 30 Göteborg
Sweden
Tel. +46-31-773 3645
Email: christer.erseus at zool.gu.se
-----Original Message-----
From: owner-annelida at net.bio.net [mailto:owner-annelida at net.bio.net] On
Behalf Of Geoff Read
Sent: den 14 maj 2005 08:12
To: annelida at net.bio.net
Subject: Gilled FW oligochaete
Hi,
I've been given a specimen of a small freshwater oligochaete from a New
Zealand North Island river to identify. It is about 5mm long, has about 30
pairs of lateral gills posteriorly, one pair per segment. I don't think it is
a Phreodrilus (Phreodrilus branchiatus Beddard from Chile has lateral gills,
but it hasn't been recorded from here) because there are too many chaetae per
fascicle (4 rather than 2). Capillaries as well as short simple-pointed
chaetae are present dorsally anteriorly. It's quite a muscular- looking worm
due to lat and ventral grooves, but this may be a fixation artifact. A
'thick' head and tapered tail with a distinct anal opening.
I'd struggle to id an oligochaete tracking through reproductive organ
characters as one is supposed to - assuming there were any developed. Any
other suggestions for gilled species to check out? Anyone interested in taking
a look?
Geoff
--
Geoff Read <g.read at niwa.co.nz>
http://www.annelida.net/
-- ANNELIDA LIST
Discuss = <annelida at net.bio.net> = talk to all members
Server = <biosci-server at net.bio.net> = un/subscribes
Archives = http://www.bio.net/hypermail/annelida/
Resources = http://www.annelida.net/
--