Gomphidae of Guangdong & Hong Kong, China (Odonata: Anisoptera) 2177
Author
Wilson, Keith Duncan Peter
Author
Xu, Zaifu
text
Zootaxa
2009
2009-08-06
2177
1
62
journal article
11755334
Melligomphus guangdongensis
(
Chao 1994
)
comb. nov.
Figs. 20
(a–j), 21(a–j)
Onychogomphus
sp.
: Matsuki (1989: 30–32, figs 8, 12, 16,
Hong Kong
);
Matsuki
et al
. (1990: 16
,
Hong Kong
);
Kitagawa
et al
. (1994: 12
,
Hong Kong
).
Ophiogomphus guangdongensis
Chao 1994
:
Chao (1994: 73–75
, figs 1–9, type-loc. male, Heishiding,
Guangdong
).
Melligomphus
sp.
:
Wilson (1995a: 116–117
, 123, 125,
Hong Kong
).
Melligomphus moluami
Wilson 1995b
: Wilson (1995: 325–329, figs 5–14, type-loc. Mount Butler,
Hong Kong
);
Saito & Ogata (1995: 33–34
, fig. 52,
Hong Kong
);
Wilson (1997a: 32–33
,
Hong Kong
);
Wilson (2003: 238–239
,
Hong Kong
);
Wilson (2004a: 240–241
,
Hong Kong
).
syn. nov.
Remarks:
The single male specimen described by
Chao (1994)
measured: abd. + app.
37 mm
and hw
29 mm
. These are virtually the same measurements as given for male
Melligomphus moluami
by Wilson (1995), which are abd. + app.
36 mm
and hw 29.0 mm. The descriptions also closely match and the drawings of caudal and secondary genitalia are comparable. There is a slight difference in wing venation but the two taxa are clearly synonymous. Wilson (1995) was unaware of
Chao (1994)
, which was published in
December 1994
whereas Wilson’s manuscript was submitted in
September 1993
, more than a year earlier, but published in
September 1995
.
Chao (1994)
described
guangdongensis
in subgenus
Ophiogomphus
(
Ophionurus
) Carle
, but lacking a hooked posterior appendix, it does not belong in this subgenus.
Chao (1953b)
published a very detailed account of the external morphology of
Onychogomphus ardens
Needham. Later,
Chao (1990)
selected
ardens
as the genotype species for the new genus
Melligomphus
, which he established to receive Chinese onychogomphines with,
inter alia
, superior appendages shorter than inferior appendages and without markedly hooked tips, as in
Lamelligomphus
.
Chao (1990)
created a key to the genera of Chinese Onychogompinae but there are obvious errors in this key with respect to
Melligomphus
. In couplet (8) of
Chao's (1990)
key
Melligomphus
is required to possess: "A
2
arising from the triangle". The wings of the genotype
M. ardens
were figured in
Chao (1953b)
and these figures are reproduced here (
Figs. 19a–b
). They clearly illustrate A
2
arising from the anal vein between the anal crossing (= cu-a) and the subtriangle. In fresh specimens of
M. ardens
from
Guangdong
A
2
also arises between the anal crossing and triangle (
Fig. 18i
). This character will not separate
Melligomphus
from
Ophiogomphus
. In couplet (8) of
Chao's (1990)
key
Melligomphus
was also separated from
Ophiogomphus
based on two other characters, viz. (i) anal loop 1 or 2-celled compared with 3-celled anal loop in
Ophiogomphus
and (ii) superior appandages slightly shorter than inferior appendages. In Chao’s drawings of
M. ardens
the hindwing anal loops clearly possess two cells but
Ophiogomphus sinicus
Chao
also has 2-celled anal loops (
Fig. 24e
). All the numerous
sinicus
specimens examined in this paper possess 2-celled anal loops. A superior appendage longer than inferior appendage is charcteristic of
Ophiogomphus
sensu stricto
but in Asian
Ophiogomphus
(
Ophionurus
)
sinicus
the superior appendages are shorter than inferior appendages. Of the three characters Chao used in his key to separate
Melligomphus
from
Ophiogomphus
, none reliably serve to split Asian
Ophiogomphus
(
Ophionurus
)
from
Melligomphus
!
FIGURE 20(a–j):
Melligomphus guangdongensis
comb. nov.
, Guangdong, ♂, from
Chao (1994)
— (a) abdomen, dorsal, (b) head, frontal, (c) synthorax, (d) caudal appendages, dorsal, (e) penile organ, lateral, (f) left basal hindwing, (g) right basal hindwing, (h) caudal appendages, lateral, (i) anterior hamulus, (j) posterior hamulus.
FIGURE 21(a–j):
Melligomphus guangdongensis
comb. nov.
, Hong Kong. [a–i] from Wilson (1995)— (a) ♀, head, thorax and basal abdomen, lateral, (b) ♀, occiput, frontal, (c) ♀, caudal abdomen, postgenital plate, (d) ♂, penile organ, ventral, (e) ♂, penile organ, lateral, (f) ♂, caudal appendages, lateral, (g) ♂, caudal appendages, dorsal, (h) larvae, dorsal, (i) ♂, hamuli, (j) ♀, hindwing.
In Chao’s drawings of
guangdongensis
(
Figs. 20a–j
) the superior appendages are clearly shorter than the inferior appendages but the anal loop is 3-celled, however, in three
guangdongensis
(=
moluami
) specimens examined from
Hong Kong
the anal loop is 2-celled (
Fig. 21j
).
Chao (1994)
elected to place
guangdongensis
in the subgenus
Ophiogomphus
(
Ophionurus
)
based on: "posterior hamulus produced into a short finger-like process and the inferior anal appendage with a well devloped dorsolateral spine."
Carle (1986)
divided the genus
Ophiogomphus
into three subgenera, namely:
Ophionuroides
Carle
,
Ophionurus
Carle and
Ophiogomphus
Selys. When Carle
created the subgenus
Ophionurus
it was characterised as follows, “Posterior hamulus elongate with a hook-like apex, male epiproct with a well developed dorsolateral spine, female postocellar ridge well developed medially”. The posterior hamulus of
guangdongensis
is elongate and acuminate and not hook-like. The inferior appendage has a dorsolateral spine in the subgenus
Ophionurus
but not in
Ophiogomphus
sensu stricto
. Species within the genus
Melligomphus
, where the males are known, do not possess inferior appendages with a sub-basal spine i.e
Melligomphus ardens
(Needham)
,
Melligomphus cataractus
Chao & Liu
and
Melligomphus ludens
(Needham)
. However, the presence or absence of an inferior appendage with a sub-basal spine or tooth may not be a useful character at generic level (it is a subgeneric character in
Ophiogomphus
). The general structure of the penile organ and hamuli may serve as more reliable generic characters. The penile organ of
Melligomphus ardens
(
Fig. 19c
) strongly resembles
guangdongensis
(cf
Figs. 20e
&
21d–e
). The median segment of both species' penile organs features a prominent, somewhat flattened, posterior lobe (also known as the prepuce or preputial fold) and ventrally a pair of raised and prominent (nose–like), heavily scleritized structures to which the bilobed distal segment is attached. These scleritized structures are also prominent in
Melligomphus
congeners i.e.
Melligomphus cataractus
(
Fig. 19e
) and
Melligomphus ludens
(
Fig. 19f
). However the penile organ of
Ophiogomphus sinicus
also possesses these features (cf
Fig. 19d
&
24d
), but not quite so pronounced. Perhaps the most reliable character to distinguish
Melligomphus
from
Ophiogomphus
is the structure of the posterior hamulus. In general appearance
guangdongensis
strongly resembles
Melligomphus
congeners, especially
Melligomphus ludens
(see
Wilson 1995b
), whereas there is no general resmblance to species of
Ophiogomphus
(
Ophionurus
)
or
Ophiogomphus
sensu stricto
.
In summary the genus
Melligomphus
is reliably characterised by: (i) inferior anal appendages of male slightly longer than superior appendages, (ii) both branches of superior appendages more or less parallel, (iii) penile organ with a prominent postgenital lobe and pair of raised, prominent, nose-like scleritized structures, (iv) anal triangle of male 4-celled, (v) anal loop 2-celled or occasionally 1 or 3-celled, and (vi) posterior hamulus with an acuminate tip, not overtly hook-like. The only species known from
China
in the subgenus
Ophiogomphus
(
Ophionurus
)
is
sinicus
Chao (1954)
, which bears very little resemblance to its North American congeners (see remarks section under
sinicus
below).
Distribution:
China
(
Guangdong
&
Hong Kong
).