Grania (Annelida: Clitellata: Enchytraeidae) of the Great Barrier Reef, Australia, including four new species and a re-description of Grania trichaeta Jamieson, 1977
Author
Wit, Pierre De
Author
Rota, Emilia
Author
Erséus, Christer
text
Zootaxa
2009
2165
16
38
journal article
10.5281/zenodo.189048
cc3fea04-eca2-4526-a4f8-3cb2502bf9c3
1175-5326
189048
Grania hyperoadenia
Coates, 1990
(
Fig. 9
)
Grania hyperoadenia
Coates, 1990
: 25
–26, fig 6(1990).
New material examined:
AMS main coll. W.35560: One incomplete (posteriorly amputated) whole-mounted specimen from Lizard Island, stn. L3.
Description:
Length>
3.1 mm
, segment number> 27. Prostomium 73 µm wide, 61 µm long; prostomial epidermis 20 µm thick on all sides. Width 113 µm at peristomium; 167 µm at IV; 134 µm at XII. Lateral chaetae present posteriorly from XV (from XVIII in original description); chaetae 50 µm long, L-shaped, entally bent into a slender, 15 µm long foot (
Fig. 9
A); chaetal index=3.49, n=6, sd=0.703. Clitellum in uneven rows of granular gland cells interspersed with hyaline gland cells at a frequency of about 2:1(
Fig. 9
B). Head organ absent. Sperm sac extending to XVI, and egg sac extending to XVII (XIX and XX in original descr., respectively). Dorsal blood vessel commencing in XXV (XX in original descr.). Coelomocytes (
Fig. 9
C) abundant throughout body, oval, 12–16 µm across on the widest point, flattened, granular with unstained nucleus. Penial apparatus consisting of small invagination at male pore, surrounded by oval gland, 55 µm long and 40 µm wide (
90 x
50 µm in original descr.); no stylet present. Spermatheca with ectal duct wedged into ampulla, about 50 µm long and 20–25 µm wide (
84 x 16
µm in original descr.); ampulla roughly spherical, 40µm in diameter (89 µm in original descr.) (
Fig. 9
D).
Remarks:
This specimen conforms to Coates’ (1990) original description of
G. hyperoadenia
from the Albany area (W
Australia
) with only minor differences, noted above. As
G. hyperoadenia
originally was described from a single specimen, this is the first record of variation in the species. The slight deviations concerning the first lateral chaetae as well as the length of the sperm and egg sacs are well within normal intraspecific variation ranges, when compared to other species. Both the glandular structure of the penial apparatuses and the spermathecae are smaller in this specimen than in the
holotype
of
G. hyperoadenia
.
Our study provides the first information on the clitellar cell pattern, the coelomocytes and the head organ in the species.
Distribution and habitat:
Albany area, south-western
Australia
and Lizard Island, Great Barrier Reef (new record). Subtidal sand, from
1.5 to 4 m
depth.