Mesogomphus genei, Morton, 1924

K. J. Morton, 1924, The Dragon-flies (Odonata) of Palestine, based primarily on collection made by Dr. P. A. Buxton, with Notes on the Species of the Adjacent Regions., Transactions of the Entomological Society of London 1924, pp. 25-44 : 35-38

Mesogomphus genei Selys.

Haifa, ♂, 28.iii.22, ♀, 4.iv.22 ; Wadi Kelt, ♂, 16.v.23, ♀, 9.iv.23 .

The only references known to me as t o the occurrence of Mesogomphus in the region are those of de Selys, who records under the name of Onychogomphus hagenii a ♂ from Beirut in his collection, adding that Hagen had received the same species from Syria through Lederer. As I a m disposed to doubt that the above Palestine examples are different from the Beirut insect, my use of the name genei requires explanation.

An altogether extraordinary confusion has arisen in connection with three Selysian names: O. genei (Selys, 1841, type ♀, Sicily, Mus. Turin), O. hagenii (Selys, 1871, ♂♀, Egypt, Mus. Berol.) and O. costae (Selys, 1885, ♂, Oran, coll. Selys). I n 1871Selys separated from genei under the name of hagenii , the ♂♀ from Egypt which he considered he had erroneously associated with his type ♀ of genei from Sicily in Mon. Gomphines, a step be it noted primarily due t o a misapprehension on his part regarding a ♂ from Oran (thought by him to be the true ♂ of genei ) subsequently known as O. costae , a species which occurs in Spain. I n 1878 he reported the ♂ hagenii from Beirut, associating with it a darker example from Abyssinia communicated by McLachlan. I n 1887 he says of his Beirut example that it is like pumilio only a little larger and not quite so pale, more greenish: genei from Sicily (with excelsus Costa as a synonym) he says is larger than hagenii and the colour of the body darker.

McLachlan (1897) records from Algeria, all under the name of genei , examples of both sexes from Biskra and a pair from Lac Houbeira; to the former he was inclined at first to apply the name genei (as represented by the original type from Sicily), these having the abdomen less darkly marked and being without a dark band on the top of the front before the ocelli. The Lac Houbeira examples he inclined to consider hagenii Selys (with excelsus Costa as a synonym -in this differing from Selys); these having the abdomen somewhat heavily marked with black and a broad blackish band on the top of the front before the ocelli. McLachlan indicates that hagenii from Abyssinia seems to differ from the Lac Houbeira examples only in having the abdomen still more blackish at the extremity.

To follow McLachlan, the Palestine examples would appear to agree better with his conception of genei than of hagenii , but the differences in size and colour which Selys and he mention seem to be of doubtful value. Whether there are two species, and both of them present in the Mediterranean region, may remain an open question until more material is available especially from Sicily and Sardinia, but I incline to the view that there is only one, Mesogomphus genei , and that M. hageni should be cancelled.

As Dr. Ris has pointed out (in litt.), much has been written on this subject, but it is all based on a very small number of actual specimens and observations. For the better understanding of the questions involved he has been good enough to take the trouble of tabulating the relative literature, and his lists are given herewith with his approval. These cannot fail to be useful to any one who may in the future have occasion to go into the matter. Words enclosed in square brackets are personal additions and appreciations by Dr. Ris.

MESOGOMPHUS GENEI .

Gomphus Genei Selys, Rev. Zool. aout 1841, p. 245 (p. 5 sep.), ♀, Sicily, Mushe de Turin.

Selys Hagen, Rev. Odon. pp. 101 and 384 (1850), the same example.

Onychogomphus Genei Selys, Synops. Gomph. p. 17 (1854) (pars), the same example.

Selys Hagen, Monogr. Gomph. p. 311 (1857) (pars), the same example, p. 312 described anew.

Selys Ann. Soc. Ent. France (3) 8, p. 742 (1860), the same example.

Lindenia Genei, Kirby Cat. p. 59 (1890).

Onychogomphus Genei McLachlan, Ent. Mon. Mag. (2) 8, p. 155 (1897) (pars), 3 ♂ 2 ♀, Biskra.

Martin, Ann. S. Ent. France 79, p. 99 (1910), Algeria

[Compilat., no new material]. Le Roi, Deutsche Ent. Ztschr. 1915, 'p. 621 (1915),

Algeria, ex auct.

MESOGOMPHUS HAGENI .

Onychogomphns Genei Selys, Synops. Gomph. p. - 17 (1854) (pars), ♂♀, Egypt, Mus. Berol. Selys Hagen, Monogr. Gomph. p. 313 (1857) (pars), ♂♀, Egypt, Mus. Berol. -Tab. 3, fig. 4, ♂♀.

Onychogomphus Hagenii Selys, Ann. Soc. Ent. Belg. 14, p. 15 (1871), nov. nom. for the ♂ ♀, Egypt, Mus. Berol. Selys, 3 add. Synops. Gomph. p. 11 (1873), new descrip- tion of the same pair [Whether after new examina- tion? very improbable].

id. 4 add. Synops. Gomph. p. 21 (1878), 1 ♂ Beirut d. Staudinger, coll. Selys, more lightly coloured [no exact description; 1 ♂, Abyssinia coll. MCLach-] lan, more darkly coloured [no exact description;] Syria through Lederer sec.Hagen

Gomphus excelsus Costa, Bull. Soc. Ent. Ital. 15, p. 333 (1884), [ex Cat. Kirby-—not seen by Ris] to Hagenii after McLachlan, 1897.

Onychogomphus Genei Selys, Gpts. Rd. Soc. Ent. Belg. xii, 1885, p. 8 sep. -short mention of G. excelsus Costa, which is determined as On. Genet (Hagenii according to McLachlan—see above). [The place of the descrip- tion by Costa is given as Actes Acad. Sc. Naples 1883—not seen by Ris.]

Onychogomphus Hagenii Selys , Cpts. Rd. Soc. Ent. Belg. xii, 1885, p. 8 sep., mentioned.

Selys, Ánn. Soc. Ent. Belg. 31, p. 28, 67 (1887), the same material as 1878.

Lindenia Hagenii, Kirby Cat. p. 59 (1890).

Onychogomphus Costae Karsch, Ent. Nachr. 16, p. 377 (1890), 1 ♂, Egypt leg. Ehrenberg Mus. Berol. [after the short diagnosis surely not Costae nob., but very probably the old example of the Synops. and Monogr. Gomph. and therefore the type of Hagenii ; a ♀ is not mentioned].

Onychogomplznv Genet Selys, Ann. Soc. Ent. Belg. 36, p. 10-11 sep. (1892), 1 ♂♀, coll. Selys, Sardinia

leg. Costa [to Hagenii according to McLachlan, 18971. Portugal, observed by M. Girard [not seen by Selys, whether by McLachIan is not stated; this locality probably uncertain:? may refer to Costae ] Onycliogomphus Hagenii Selys, ibid. p. 11 (1892)) the material of 1878-1 887.

.

Onychogomphus Hagenii , sub Genei , McLachlan, Ent. M. Mag. (2) 8, p. 155 (1597)) 1 ♂♀,Lac Houbeira, Algeria. With these Houbeira examples, excelsus Costa [which McLachlan had in his coll. from Sardinia according to Selys, 18921 is said generally t o agree.

Onychogomphus Hagenii Martin, Feuille j. Nat., No. 370, p. 249-50 (sep.) (1901), Biskra; the larva is said from Onychogomphus t o be widely different and t o have the type of the usual Gomphus larvae [what I hold to be certainly wrong!.

]

Mesogomphus Hageni Ris, Ber. Senckenb. Nat. Ges. 1909, p. 27, mentioned from Eritrea.

Onychogomphus Hageni Martin, Ann. Soc. Ent. France 79, p. 100 (1910), Algeria [Compilat., no new material].

Mesogomphus Hageni Ris, Novitat. Zool. 20, p. 468 (1913)) Biskra.

Onychogomphus Hageni Le Roi, Deutsche Ent. Ztschr. 1915, p. 621, Algeria, ex auct.

Mesogomphus Hageni Ris, Ann. S. Afr. Mus. 18, 3, p. 344 (1921))figs. 46, 47, 48, Tab. 9, fig. 2, South Africa, Katanga, Abyssinia, Eritren, Tunisia, Algeria.