New records of plant mites (Acari, Acaridae, Tetranychidae) from Guadeloupe and Marie Galante with descriptions of five new eriophyid species
Author
Flechtmann, Carlos H. W.
Author
Etienne, Jean
text
Zootaxa
2002
47
1
16
journal article
51449
10.5281/zenodo.155892
a1b4b53d-0b3a-405f-b1b6-1b62348b9e2f
11755326
155892
Ectomerus triquetrus
n.sp.
(
Fig. 3
)
DIAGNOSIS
An
Ectomerus
species with an equilateral triangular prodorsal shield lobe, sixrayed empodia, scapular setae set on distinct tubercles and pointed upwards.
FEMALE
(n = 6). Idiosoma 177 (123181), 49 (3939) wide.
Gnathosoma
downcurved; basal seta 3 (3); antapical seta not discernible; chelicerae 16 (1316).
Prodorsal shield
30 (2330) including lobe, 33 (2633) wide; frontal lobe an equilateral triangle, 5 (36) long. Shield design a pattern of longitudinal lines, median line restricted to posterior third, admedian lines complete, broken; submedian and additional lines broken. Laterally with curved lines, in some specimens outlining an elongate oval spot. Dorsal shield tubercles distinct, near rear shield margin, 14 (1114) apart, directing the 19 (1820) long scapular setae (
sc
) upwards and slightly ahead (see remarks).
Legs
with all usual setae present; leg
I 24
(1824); femur 6 (56), femoral seta (
bv
) 9 (59); genu 3 (35), genual seta (
l"
) 23 (1423); tibia 5 (45), tibial seta (
l'
) 5 (35); tarsus 5 (46), solenidium 4 (45), empodium 4 (4), 6rayed, dorsal seta (
ft'
) 5 (46), lateral seta (
ft"
) 16 (16), unguinal seta (
u'
) 4 (24). Leg
II 22
(1522); femur 7 (57),
bv
7 (57); genu 3 (23),
l"
10 (610); tibia 4 (23); tarsus 4 (3 5), solenidium 8 (78), empodium 5 (46), 6rayed,
ft'
4 (45),
ft"
18 (1618),
u'
3 (23).
Coxae
unornamented except for a broke, curved, longitudinal line on coxa I. Coxae I with a short sternal line, 3 (34), forked to rear. Coxal seta I (
1b
) 8 (68), 6 (57) apart; coxal seta II (
1a
) 16 (1719), 8 (69) apart; coxal seta III (
2a
) 30 (2630), 17 (1318) apart. Coxigenital area with 4 (34) microtuberculate annuli.
Genitalia
19 (1519) wide, 10 (910) long; epigynium with 12 (1214) longitudinal ribs, more or less broken centrally; genital seta (
3a
) 11 (911). Genitalia somewhat appressed to coxae, anterior apodeme of internal genitalia shortened.
Opisthosoma
evenly rounded in cross section. Lateral seta (
c2
) 18 (1719), on annulus 4 (34) from genitalia rear margin; ventral seta I (
d
) 46 (3546), 33 (2633) apart, on annulus 19 (1118); ventral seta II (
e
) 41 (3348), 20 (1625) apart, on annulus 37 (2437); ventral seta III (
f
) 18 (1218), 15 (915) apart, on annulus 66 (4259) or 6th from rear. Total ventral annuli 71 (4864), beset with rounded microtubercles; total dorsal annuli 73 (4470) with elongate microtubercles, plus 8 (914) caudal, wavy annuli with minute microtubercles on ring margin. Caudal seta (
h2
) 40 (4046); accessory seta (
h1
) missing.
MALE
(n = 3). Smaller than female, 116157, 3647 wide.
Gnathosoma
: basal seta 2; antapical seta not discernible; chelicerae 1415.
Prodorsal shield
2426, including 34 frontal lobe, 2627 wide. Dorsal shield tubercles 1218 apart,
sc
1618.
Leg
I 1819
; femur 56,
bv
67; genu 3,
l"
1215; tibia 34,
l'
23; tarsus 4, solenidium 4, empodium 4, 6rayed,
ft'
57,
ft"
1215,
u'
12. Leg
II 1718
; femur 6,
bv
8; genu 23,
l"
79; tibia 23; tarsus 34, solenidium 7, empodium 34, 6rayed,
ft'
45,
ft"
1516,
u'
23.
Coxae
:
1b
611, 57 apart;
1a
1115, 69 apart;
2a
2326, 1315 apart; coxisternal area with 34 microtuberculate annuli.
Genitalia
1315 wide, 812 long, smooth;
3a
89.
Opisthosoma
:
c
2
1418, on annulus 25;
d
3338, 2633 apart, on annulus 1012;
e
2733, 1724 apart, on annulus 22 26;
f
1213, 1013 apart, on annulus 3949 or 6th from rear. Total ventral annuli 4555; total dorsal annuli 3458 with elongate microtubercles plus 1114 annuli with minute marginal microtubercles. Caudal seta (h2) 2835;
h1
missing.
TYPE
MATERIAL
female
holotype
,
58 female
and
4 male
paratypes
, from
Buchenavia capitata
(Combretaceae)
, Les Abymes,
Guadeloupe
, coll. J. Etienne,
2 Sept. 2001
, on 18 microscopic preparations in the collection of Departamento de Entomologia, Fitopatologia e Zoologia Agrícola, Universidade de São Paulo,
ESALQ
, Piracicaba, São Paulo,
Brazil
. One
paratype
slide deposited in the
New Zealand
Arthropod Collection.
RELATION TO
HOST
the mites were collected from fingerlike galls on leaves and vagrant in flowers.
ETYMOLOGY
The specific designation
triquetrus
is based on the Latin
quetrus
, a suffix meaning angled, cornered or sided;
triquetrus
refers to the triangular front lobe of the prodorsal shield.
REMARKS
1.) In one male specimen the internal genital structures (
Fig. 3
, IGM) could be observed. Following the description given by
Nuzzaci(1976)
, the ejaculatory duct (= vas deferens), a rather voluminous seminal vesicle, and two testicles are recognizable, on the contrary of only one testis as mentioned by
Nuzzaci and Alberti (1996)
,
Nuzzaci and Solinas (1984)
and
Nuzzaci (1976)
.
FIGURE 3
.
Ectomerus triquetrus
n.sp.
AD, anterior dorsal aspect; AL, anterior lateral aspect; CD, caudal dorsal aspect; CGF, coxigenital area of female; EG, epigynia of female paratypes; GM, genitalia of male; IGF, internal genital structures of female; IGM, internal genital structures of male [ED, ejaculatory duct; SV, seminal vesicle; TS, testes]; L1, leg I; L2, leg II.
2.) The new species is the fourth known species in the genus
Ectomerus
. All four species were collected from plants in the family
Combretaceae
:
E. anysis
Keifer
, l970, from
Terminalia muelleri
in
Australia
,
E. chebulae
Mohanasundaram, 1980
, from
T. chebulae
in
India
,
E. systenus
Meyer, 1990
, from
T. sericea
in
South Africa
and the new species from
Buchenavia capitata
in
Guadeloupe
. These species can be separated by the shape of the frontal lobe: bluntly rounded distally in
E. anysis
, an equilateral triangle in the new species, ending in a thin, sharp, elongate point in
E. chebulae
and
E. systenus
. In
E. chebulae
the first setiferous coxal tubercles are in an advanced position near the inner corners of forecoxae, well ahead of anterior coxal approximation, while in
E. systenus
they are about level with anterior coxal approximation.
3.) The setiferous tubercles on prodorsal shield in
E. triquetrus
are soft and the scapular setae are directed up and forwards in the living specimens; in the process of microscopic preparations, according to the angle at which the coverslip is lowered, setae and tubercles are bent forwards, sidewards or even backwards.