AN ANNOTATED PRELIMINARY LIST OF THE CHIRONOMIDAE (DIPTERA) OF ZURQUÍ, COSTA RICA Abstract Introduction
Author
Epler, John H.
461 Tiger Hammock Road, Crawfordville, Florida, 32327, U. S. A.
johnepler3@comcast.net
text
CHIRONOMUS Journal of Chironomidae Research
2017
2017-04-21
30
30
4
18
https://www.ntnu.no/ojs/index.php/chironomus/article/view/2240
journal article
10.5324/cjcr.v0i30.2240
2387-5372
7987298
Lipurometriocnemus
- Four species were collected, three of them undescribed.
Lipurometriocnemus
was first described from the British West Indies by
Saether (1981)
, with
L. glabalus
as the sole species.
Saether (1982)
then described
L. vixlobatus
from
South Carolina
,
USA
. The two species were supposedly separated by the absence of setae on R
1
, a weak inferior volsella and a “slight hump on tergite IX representing a reduced anal point” in
L. vixlobatus
.
Cranston & Oliver (1988)
reported
L. vixlobatus
from the
Yukon Territory
of
Canada
, and examined
paratypes
of
L. glabalus
and a single specimen (which they thought to also represent
L. glabalus
) from Braulio Carillo National Park in
Costa Rica
(the Zurquí site is adjacent to a portion of the huge park). They noted that the two species were difficult to separate because of variation in the supposedly diagnostic characters, but gave no reason why they assigned the Yukon specimen to
vixlobatus
, which following its description should lack any setae on R
1
, instead of assigning it to
L. glabalus
. I noted such variation in the volsellae and “anal hump” in the Zurquí material I’ve designated as
L. glabalus
; there was variation in the length/ breadth of the gonostylus but much appeared due to the viewing angle. I saw no specimens in which R
1
was devoid of setae and considered all material I put in this group to be
L. glabalus
(
63 specimens
).
Table 1. Selected measurements of
Gravatamberus
guatemalticus
| Specimen # |
Month collected |
cell m setae |
subcosta setae |
costal extension, µm |
| 4399193 |
OCT |
0 |
5 |
175 |
| 4401710 |
JUN-JUL |
1 |
4 |
195 |
| 4401650 |
JUN-JUL |
0 |
6 |
200 |
| 4401625 |
OCT |
0 |
5 |
155 |
| 4400249 |
JUN |
1 |
5 |
180 |
| 4405861 |
MAY |
1 |
5 |
153 |
| 4401624 |
OCT |
0 |
9 |
200 |
| 4400246 |
JUN |
1 |
7 |
188 |
| 4399225 |
JUN |
0 |
5 |
155 |
| 4399224 |
JUN |
9 |
5 |
175 |
| 4406521 |
APR |
18 |
12 |
163 |
| 4370228 |
MAY |
17 |
17 |
153 |
| 4363952 |
APR |
24 |
14 |
128 |
| 4363944 |
FEB |
11 |
7 |
188 |
| 4363957 |
APR |
19 |
11 |
133 |
| 4399449 |
MAY |
15 |
10 |
165 |
| 4406482 |
APR |
13 |
6 |
150 |
| 4406453 |
MAY |
16 |
10 |
138 |
My
L
. sp. ZUR–1(
eight specimens
) has genitalia similar to those of
L. glabalus
but has a very low AR (~0.32–0.58) compared to what is being called
L. glabalus
today (following
Cranston & Oliver 1988
and
Andersen et al. 2016
). In
Saether’s (1981)
original description of
L. glabalus
, all of the
type
material lacked antennae, but it is now apparently assumed that the species has an AR similar to that of
L. vixlobatus
– around 1.60–1.75. Zurquí material of
L. glabalus
had ARs> 1.70.
My
L
. sp. ZUR–2 (
36 specimens
) has an AR around 1.76–1.85 and genitalia very similar to those of
L. glabalus
, except the proximal portion of the gonostylus bears a hump that separates it from that of
L. glabalus
. Further work (i.e., measurements of other body parts, etc.) may show this taxon may also belong with
L. glabalus
.
My
L
. sp. ZUR–3 (
two specimens
) has an AR of about 1.0 or less and has a distinctively pronounced inferior volsella.
Andersen et al. (2016)
described two new
Lipurometriocnemus
species
from
Brazil
and provided a key for the known species. Their
L. biancae
has a pronounced inferior volsella, but not the same as
L
. sp. ZUR–3, and an AR of 1.29-1.45. Their
L. amazonicus
(AR 1.23–1.45) is very similar to
L. glabalus
, but has fewer dorsocentral setae.