Revision of Alaptus (Hymenoptera: Mymaridae) in the Holarctic region, with taxonomic notes on some extralimital species
Author
Serguei V. Triapitsyn
text
Zootaxa
2017
2017-06-21
4279
1
1
92
journal article
31845
10.11646/zootaxa.4279.1.1
bd2c96f3-38a4-4d90-85d6-9b90db5936fe
1175-5326
1010234
9A6B42AF-E5B1-488D-9C15-4868E96F0363
Alaptus
Westwood, 1839
Alaptus
Westwood 1839
: 116
(key, etymology [footnote]), 119 (diagnosis), 120 (mentioned), 144.
Type
species:
Alaptus minimus
Westwood
, by monotypy.
Alaptus
Westwood
:
Walker 1846
: 49
(key), 50 (short diagnosis);
Foerster 1856
: 120
(brief diagnosis);
Dalla Torre 1898
: 428
(catalog);
Perkins 1905
: 197
(diagnosis);
Girault 1908
: 179
–182 (history, distribution, host associations, diagnosis), 193– 194 (key);
Girault 1910
: 244
(list of species, discussion);
Girault 1911b
: 323
(list of North American species);
Girault 1912
: 126
–127 (key to Australian species);
Girault 1929
: 9
–10 (key to North American species, brief diagnosis);
Soyka 1937
: 74
–75 (overview);
Soyka 1939a
: 17
(overview);
Soyka 1939b
: 30
(key to European species), 31 (list of non- European species);
Debauche 1948
: 53
–56 (diagnosis, discussion, list of, and key to European species);
Soyka 1948
: 74
– 75 (key to females of European species);
Debauche 1949
: 9
–10 (diagnosis, key to African species);
Soyka 1949
: 12
–13, 15 (placed in family Alaptidae within superfamily Alaptoidea);
Kryger 1950
: 29
(key), 31–33 (nomenclatural history, diagnosis, remarks); Nikol’skaya 1952: 540 (key);
Hincks 1959
: 138
–139 (historical review, diagnosis), 140–141 (key);
Annecke & Doutt 1961
: 9
(short diagnosis, distribution, comments);
New 1969
: 181
–192 (biology);
Hellén 1974
: 14
(diagnosis, key to species in
Finland
);
Trjapitzin 1978
: 521
, 523 (key to European species);
Schauff 1984
: 42
–43 (diagnosis, comments);
Noyes & Valentine 1989
: 21
–22 (diagnosis);
Yoshimoto 1990
: 23
–24 (synonymy, diagnosis, list of New World species);
Beardsley & Huber 2000b
: 5
–7 (brief diagnosis, key to Hawaiian species);
Triapitsyn & Huber 2000
: 612
(remarks);
Lin
et al.
2007
: 20
–21 (synonyms, brief diagnosis, list of Australian species);
Huber 2009a
: 235
(key);
Huber 2009b
: 18
–19 (short diagnosis); Huber
et al.
2009: 284 (brief comments);
Pricop 2010b
: 92
(list of nominal species from Europe);
Anwar & Zeya 2014
: 31
–32 (brief diagnosis and key to Indian species).
Parvulinus
García Mercet 1912
: 332
–333.
Type
species:
Parvulinus auranti
García Mercet
, by monotypy. Synonymized under
Alaptus
by
Girault 1913a
: 221
.
Metalaptus
Malenotti 1917
: 339
–340.
Type
species:
Metalaptus torquatus
Malenotti
, by monotypy. Synonymized under
Alaptus
by
Girault 1917
: 1
and then listed under
Alaptus
by
Debauche 1948
: 53
, 55 and
Debauche 1949
: 9
.
Metalaptus
Malenotti: Malenotti 1918
: 81
(diagnosis).
Parvulinus
Mercet
: Nikol’skaya 1952: 540 (key).
Alaptus
(
Parvulinus
) Mercet
:
Thompson 1958
: 565
.
Diagnosis.
Both sexes: body very small (much less than
1 mm
long), length of slide-mounted specimens (excluding the exserted part of ovipositor in females)
0.18–0.68 mm
; mandible 2-dentate; fore wing posterior margin with a basal incision (as in
Fig. 129
); tarsi 5-segmented; mesosoma sessile, mesophragma strongly projecting into gaster, midlobe of mesoscutum usually with a pair of adnotaular setae. Female: antenna almost always with funicle 5-segmented and clava entire, except rarely funicle with a minute sixth segment (F2) in some specimens from the Australasian and
Oriental
regions, as noted by
Lin
et al.
(2007)
and illustrated by
Anwar
et al.
(2015)
for
A. indicus
Anwar & Zeya.
Male: antenna with flagellum 8-segmented.
Mandibles are usually not enlarged in
Alaptus
except in one undescribed species from Bella Vista, Buenos Aires Province of Argentina, in which they are very large (
Fig. 1
). I have examined 4 females and 1 male in MLPA, mounted on 3 slides (collected on
20.xii.1963
and
25.xii.1963
most likely by A.A. Ogloblin, and labeled by him as “Huevos de Psocides Tronco
Eucalyptus
” [eggs of psocids
Eucalyptus
stem] under his manuscript name “
Alaptus mandibularis
”.
Species recognition in this diverse genus outside of Europe and also perhaps the Nearctic region is usually quite difficult (most taxa were described without providing proper diagnoses and not in a revisionary context); of diagnostic importance are body size and color, proportions of the antennal segments, chaetotaxy on the fore wing, and ovipositor length. But because of often a considerable intraspecific variation in some of them, there are not too many good diagnostic characters to help separate some similar species of
Alaptus
. Good quality specimen preparation on microscopic slides is almost always required for accurate identification of these minute wasps. In Europe, however, with experience the most common species may be generally recognized from properly critical point-dried and card- or point-mounted specimens.
Classification.
Alaptus
is a readily recognizable genus in the Palaearctic region, so any appropriate generic key to the
Mymaridae
can be used for its identification:
Annecke & Doutt (1961)
for the world genera,
Schauff (1984)
for the Holarctic genera,
Triapitsyn & Huber (2000)
for the Palaearctic genera, and
Pricop (2013)
for females of the European genera. Long after
Perkins (1912)
based his subfamily
Alaptinae
(within family Alaptidae) on
Alaptus
,
Viggiani (1989)
placed it in the mymarid subfamily
Mymarinae
, tribe Alaptini Perkins, based solely on the structure of male genitalia, but later
Lin
et al.
(2007)
and
Huber (2009a)
treated it as a member of the informal
Alaptus
group of genera.
Distribution.
Cosmopolitan.
Hosts.
See
New (1969)
,
Huber (1986)
,
Triapitsyn (2002)
, and
Noyes (2016)
. The reliable host records of
Alaptus
spp. are from eggs of various Psocoptera (
Enock 1895
,
1915
;
Bakkendorf 1934
;
Ghesquière 1939
;
Kryger 1950
;
Hincks 1959
,
1960
;
New 1969
;
Huber 1986
;
Viggiani & Jesu 1988
; etc.). All other, non-psocopteran, host records need confirmation and are almost certainly incorrect due to inadequate rearing methods, particularly those from various Coccoidea (
Hemiptera
) on plant material placed in rearing cages; these are not considered in this review and are therefore purposely omitted. Other aspects of biology of
Alaptus
species are mostly unknown except for a few European species (e.g.,
New 1969
;
Broadhead & Cheke 1975
;
Cheke 1977
) and one Nearctic species (
Spruyt 1927
); although, based on the analysis of the known host records, its seems that at least some of the species tend to be oligophagous or even polyphagous within an ecological niche: those parasitizing psocid eggs on leaves do not generally parasitize those on bark and vice versa (
New 1969
).