Turbo-taxonomy: 21 new species of Myzostomida (Annelida)
Author
Summers, Mindi M.
Author
Al-Hakim, Iin Inayat
Author
Rouse, Greg W.
text
Zootaxa
2014
3873
4
301
344
journal article
42367
10.11646/zootaxa.3873.4.1
fb49ba3b-9228-4653-bad8-a22bf4828785
1175-5326
252208
84F8465A-595F-4C16-841E-1A345DF67AC8
Myzostoma miki
n. sp.
Summers & Rouse
Fig. 4
C
Holotype
:
SIO-BIC A3662
hologenophore
(1 spm: 95% ethanol). Wongat
Island
, Madang,
Papua New Guinea
(
5° 8.093'S
,
145° 49.338'E
), less than
20 m
.
Collected using scuba on
4 December 2012
by MMS and GWR. Genbank (COI—KM491751).
Host.
Clarkcomanthus luteofuscum
HL Clark (
Comatulidae
,
Comatulida
, Crinoidea). SIO-BIC E5951 (tissue subsample in 95% ethanol). Genbank (COI—KM491782).
Paratypes
:
SIO-BIC A3834 (2 spms: 95% ethanol). Hook Reef, Whitsunday Islands,
Australia
(
20° 7'5.03"S
,
148°55'25.30"E
),
10 m
.
Collected using scuba on
22 June 2011
by GWR and Nerida Wilson. Genbank (COI—KM014201). Host:
Clarkcomanthus luteofuscum
,
SIO-BIC E4726; Genbank (16S—KM491765).
Etymology.
Named for Michael Summers, father of MMS.
Diagnosis and description.
Holotype
body circular, ~
2 mm
in diameter following fixation. Dorsal surface with elevated hexagonal ridges in 5 rings, resembling a honeycomb (
Fig. 4
C). Body margin with 20 short-medium length cirri, equal length. Mouth and cloaca on ventral surface, in line with parapodia. Proboscis with 9 papillae. Five pairs of parapodia midway between midline and body margin. Paired penes in line with third pair of parapodia. Four pairs of lateral organs midway between parapodia and body margin, alternating with the former.
Remarks.
Myzostoma miki
n. sp.
can be distinguished from other shallow-water myzostomids by its hexagonal honeycombed ridged pattern on the dorsal surface (
Table 1
). Two other species have been described with a pentagonal dorsal patterning.
Myzostoma chelonium
McClendon, 1906
and
Myzostoma chelonoidium
McClendon, 1906
were both described associated with the same host—
Calometra discoidea
Carpenter, 1888
—from the same locality—Suruga Gulf and Sagami Sea,
Japan
, and are possibly the same species. These specimens are described as circular and elongate, respectively, and drawings show two to three rings of large (relative to their dorsal surface) square to hexagonal combs (the author stated that they gave the appearance of a turtle shell) (
McClendon 1906
). The two anterior and posterior pairs of cirri were observed to be smaller than the rest in
M. chelonium
—a feature not seen in
Myzostoma miki
n. sp.
The difference in host, locality, and overall appearance of the pentagonal ridges allows separation of these two Japanese species from
Myzostoma miki
n. sp.
One species known to associate with
Comatulidae
may (or may not) have a complex dorsal patterning—
Myzostoma atrum
Atkins, 1927
.
Myzstoma
atrum
was described from the Great Barrier Reef, associated with
Comatula pectinata
(Linnaeus)
and another unidentified crinoid. This species has a dorsal surface that varied among specimens, likely due to poor preservation. One drawing depicts a specimen with many small ridges, similar to
Myzostoma miki
n. sp.
, but these ridges were described as irregular folds in the dorsal surface.
Myzostoma atrum
was also found on a different host, recorded as dark purple, and lacked marginal cirri—all features which distinguish it from
Myzostoma miki
n. sp.