The Male Genitalia of the New Zealand Tineidae.
[Read before the Nelson Philosophical Society, 3rd November, 1926; received by Editor, 5th November, 1926; issued separately, 10th August, 1927.]
Writing in 1914, Mr. E. Meyrick (2) listed 46 species of Tineidae as occurring in New Zealand, and though at the present date 73 species are recognised, the family still remains rather poorly represented. Several species, semidomestic in habit, have been artificially introduced, but leaving these aside, we find that endemic forms largely preponderate, there being 15 endemic genera out of a total of 20 Eyer (1) states that the Tineidae “forms the basis for practically all of the types of genitalia which occur in the Tineoidea.” As far as the inference of variety goes this is applicable to the New Zealand Tineidae; genitalia structure of the simplest kind characterises some of the genera, while in others the most specialised and complicated organs are present. What is still more remarkable is that in some instances, these two extremes are to be found within the same genus. Under these circumstances, and having regard to the fragmentary character of the group here dealt with, it would serve little practical purpose to attempt a diagnosis of the genitalia characters of the family. But it may be said that usually the gnathos is imperfect (not fused) or absent, the juxta absent or small, the harpes broad, entire or with a narrow sacculus and the aedeagus, which may be straight or curved, usually long and thin.
In the case of several species lack of material has prevented examination, and it must be remembered that any conclusions arrived at are subject to such limitations. Figures of the various parts in all of the species investigated are given.
Endophthora (Fig. 1.)
A small endemic genus containing three species. Only one of these, E. omogramma Meyr. has been examined. The genitalia are of simple type. Uncus moderate, apex rounded; tegumen fused with vinculum, saccus very long and thin; gnathos and juxta absent; harpes broad, entire, dilated apically; aedeagus linear, somewhat bulbous basally. The most specialised character is the elongate saccus. On each side of the eighth tergite, near the caudal margin, is a radiating tuft of spines, probably functioning in some way in connection with reproduction.
Crypsitricha (Figs. 2–4.)
An endemic genus, allied to the preceding, containing six species. The same general description will apply, but the aedeagus is not markedly bulbous basally and in at least one species, C. stereota Meyr. the harpes are divided into two lobes.
(Lettering: a, genitalia, lateral view; aa, modified eighth segment; b, harpe; bf, reduced harpes and juxta; c, aedeagus; cb, base of aedeagus; d, uncus, dorsal view; da, uncus, ventral view; df, terminal segments of abdomen of female, dorsal view; e, transtilla; ef, terminal segments of abdomen of female, ventral view; f, juxta; g, abdomen, lateral view; t, tegumen; v, vinculum; vc, vinculum, caudal view; 7s, seventh sternite; 7t, seventh tergite; 8s, eighth sternite; 8t, eighth tergite.)
Fig. 1.—Endophthora omogramma Meyr.
Fig. 2.—Crypsitricha mesotypa Meyr.
Fig. 3.—C. roseata Meyr.
Fig. 4.—C. stereota Meyr.
Fig. 5.—Archyala opulenta Philp.
Fig. 6.—A. terranea Butl.
Fig. 7.—A. paraglypta Meyr.
Fig. 8.—A. pentazyga Meyr.
Fig. 9.—Sagephora phortegella Meyr.
Fig. 10.—Sagephora exsanguis Philp.
Fig. 11.—S. felix Meyr.
Archyala (Figs. 5–8.)
Endemic. Five species have been described, four of which are here dealt with. Uncus long, bifid or bilobed; tegumen fused with vinculum, saccus small; gnathos a pair of weak lobes not fused apically; harpes long, entire; aedeagus curved, sometimes hooked basally.
Segephora (Figs. 9–12.)
Endemic. Five species. The genitalia* are extraordinarily modified, the specialisation extending to the seventh segment, which is divided along the pleural area, the tergite assuming the function of an uncus and the sternite suggesting a fused pair of harpes. The tergite may be broad or narrow, its length being sometimes increased by a dense apical tuft of hair; the sternite is sometimes asymetrical. Within the seventh segment, which is soft and more or less membranous, lies the eighth, which may take the form of an irregular asymetrical ring or band bearing several processes, or be modified into a pair of structures placed in opposition to each other laterally. These structures are of the most complicated and involved nature though not unfitted to act as harpes, the function of which they probably undertake. The very much reduced and altered ninth segment is enclosed in turn by the eighth. Its normal constituents are, for the most part, quite unrecognisable, though vestigial harpes can usually be made out. The aedeagus was not observed and is apparently a simple membranous duct. The whole structure of the genitalia is difficult to understand and there is much variation between the different species, but it seems fairly certain that the ninth segment with its appendages—that is, the normal genitalia of other lepidoptera—is here reduced to comparatively unimportant form and function, that the eighth segment largely takes the place of the ninth, and that the seventh assists the eighth in its unusual capacity. Altogether, the genitalia characters of this small genus are among the most extraordinary and interesting in the whole of the lepidoptera.
[Footnote] * For correction in the interpretation of the parts in this genus see end of article.
Fig. 12.—S. steorpastis Meyr.
Fig. 13.—Trichophaga tapetiella L.
Fig. 14.—Monopis ethelella Newm.
Fig. 15.—M. crocicapitella Clem.
Fig. 16.—M. ornithias Meyr.
Fig. 17.—Tinea fagicola Meyr.
Fig. 18.—T. pellionella L.
Fig. 19.—T. cymodoce Meyr.
Fig. 20.—T. mochlota Meyr.
Fig. 21.—T. astraea Meyr.
Fig. 22.—T. accusatrix Meyr.
Fig. 23.—T. margaritis Meyr.
Though the consideration of the female genitalia does not come within the range of this article, it will not be out of place to draw attention to the terminal abdominal segments of the female of S. phortegella Meyr. (fig. 9, df and ef.), particularly the finger-like process on the right dorsal area of the ninth tergite. Doubtless the irregular and asymetrical form here displayed has an important connection with the unusual character of the organs of the male.
Trichophaga (Fig. 13.)
An introduced species, T. tapetiella L., is the only representative. Gnathos partially fused; tegumen and vinculum not fused, saccus long, broad on caudal half; harpes entire; juxta absent; transtilla present and of a shape frequently assumed by the juxta; aedeagus long, armed with short barbs on apical half.
Monopis (Figs. 14–16.)
Four species occur, one of which, M. typhlopa Meyr., is confined to the Chatham Islands; the cosmopolitan M. crocicapitella Clem. has been accidentally introduced. Gnathos a pair of broad lateral plates, not fusing apically; the arms of the tegumen pass right round the body and fuse beneath the saccus, that is, the elongate saccus here represents the whole of the vinculum; harpes entire, broad; aedeagus long, straight, tube-like.
Tinea (Figs. 17–26.)
Fifteen species have been recorded, including three introduced forms. It is necessary to divide the genus into two sections, one of which, “A,” has comparatively simple genitalia, while the other, “B,” exhibits extremely specialised parts.
A. Gnathos frequently absent, but may be well developed and the arms strongly connected though not fused; tegumen and vinculum fused, saccus usually well developed, absent in T. fagicola Meyr.; harpes entire or cleft; juxta small or absent; aedeagus long, tube-like, short in T. fagicola.
B. In this section the eighth segment is greatly modified, so that it takes an important part in the genitalia characters. The tergite is produced and bears a dense apical tuft (or tufts) of hair; it may also have irregular lateral processes. The sternite is usually broad, with a pair of lateral lobes, but it may be asymetrical. The tegumen and vinculum are fused, much altered and variable; the harpes are
Fig. 24.—T. dicharacta Meyr.
Fig. 25.—T. argodelta Meyr.
Fig. 26.—T. sphenocosma Meyr.
Fig. 27.—Prothinodes grammocosma Meyr.
Fig. 28.—Proterodesma byrsophila Meyr.
Fig. 30.—Lysiphragma howesi Quail
Fig. 31.—L. mixochlora Meyr.
Fig. 32.—L. epixyla Meyr.
Fig. 33.—Taleporia cawthronella Philp.
Fig. 34.—T. aphrosticha Meyr.
Fig. 35.—T. scoriota Meyr.
Fig. 36.—Mallobathra cana Philp.
Fig. 37.—M. crataea Meyr.
vestigial. The aedeagus is usually thin, sharp and curved, sometimes almost s-shaped.
Prothinodes (Fig. 27.)
Endemic. Two species. Gnathos absent. Tegumen broad apically, fused with vinculum, anal tube projecting much beyond uncus and with small dorso-lateral tufts of hair at apex, saccus fairly long; harpes deeply and widely cleft; juxta present; aedeagus long, straight.
Proterodesma (Fig. 28.)
Endemic. Monotypic. Gnathos not fused; tegumen and vinculum not fused, vinculum moderately long; harpes broad, with finger-like cucullus; aedeagus moderately long, sinuate.
Trithamnora (Fig. 29.)
Endemic. Monotypic. Gnathos absent; tegumen and vinculum fused, saccus moderate; harpes with shallow cleft, cucullus narrow; juxta present, but appears to be a modification of the anellus; aedeagus moderate, curved.
Lysiphragma (Figs. 30–32.)
Endemic. Three species. Gnathos present, not fused; uncus long, tegumen and vinculum fused, saccus small; harpes with large basal ventral fold; juxta small; aedeagus rather short, curved, thin, pointed.
One introduced Australian species. The peculiar genitalia have been already fully described (3) in Proc. Linn. Soc. N.S.W. vol. 50, p. 32.
Taleporia (Figs. 33–35.)
Three New Zealand species are known. Gnathos absent or very small; tegumen broad, fused with vinculum, saccus small; harpes with small sacculus; juxta absent, a false juxta formed by fold, armed with spines, near base of harpes; aedeagus small, finger-like.
Endemic. Thirteen species. Gnathos usually a simple band, sometimes chitinized laterally only, in some species apparently absent;
uncus with apex truncate or slightly indented; tegumen fused with vinculum, saccus small, in M. illustris Philp. moderate; harpes cleft, in M. homalopa Meyr. sacculus again cleft; juxta absent; aedeagus short or moderate.
Scoriodyta (Fig. 46.)
Endemic. Monotypic. Gnathos absent but closing membrane modified to form a pair of large leaf-like projecting flaps and a stiff plate beneath, the rectum passing behind these; tegumen and vinculum fused, saccus very small; harpes consisting of an outer weakly chitinised flap and an inner stronger one densely studded with short stout spines; juxta absent; aedeagus short, irregular.
Correction: A study of the male genitalia of the Lyonetiidae has shown me that the interpretation given above of the extremely specialised parts in Sagephora is incorrect. As, however, the blocks for the plates were already made it seemed best to allow the text to stand and to submit here the explanation of the structures as now understood. The following description should therefore be substituted for that given in the body of the paper.
Sagephora (Figs. 9—12.)
Endemic. Five species. The genitalia are extraordinarily modified, the specialisation extending to the seventh segment, the sternite of which forms a large concave plate embracing the organs from beneath. In some species, as S. felix Meyr., a basal framework, more strongly chitinised than the remaining portion, has been developed. The eighth ternite similarly, but not so completely, envelops the parts from above. Tegumen asymetrical, the apical portion an irregular strongly chitinised plate. Vinculum much reduced, fused with tegumen to form a ring. Eighth sternite a very irregular U-shaped piece, the apices, which are attached to the vinculum, ending in two prongs. In some species the right arm of the sternite is not bifid or forked, but ends in a single point, thus making the organ asymetrical. A somewhat similar form of the eighth sternite is found in Lindera tessellatella Blanch., but the position of the organ is entirely different. Harpes extremely complicated in form and quite unlike each other, the left being much larger than the right and consisting of an outer convex plate which embraces a very intricate inner structure. Aedeagus attached to right harpe, short and thick, irregularly rounded basally, apically becoming finely pointed and with a thin secondary process.
It will be necessary also to note the consequent emendations in the lettering of the figures (9, 10, 11 and 12) of the species concerned. Thus aa = tegumen and vinculum; b = part of right harpe; e = left harpe; t? = left harpe (in S. exsanguis an obliquely lateral view with the two portions forced apart); v? = right harpe and eadeagus. The opportunity also serves to point out a further error; 7t and 7s in the figures of Tinea accusatrix and T. margaritis should be respectively 8t and 8s.
List of References.
1. Eyer, J. R., The Comparative Morphology of the Male Genitalia of the Primitive Lepidoptera, Ann. Ent. Soc. Amer., vol. 17, p. 312, 1924.
2. Meyrick, E., Revision of the New Zealand Tineina, Trans. N.Z. Inst., vol. 47, p. 205, 1915.
3. Philpott, A., On a remarkable Modification of the Eighth Abdominal Segment in Lindera tessellatella Blanch. Proc. Linn. Soc. N.S.W., vol. 50, p. 32, 1925.