Art. III.—Supplement to the Stenopelmatidæ of New Zealand.
[Read before the Philosophical Institute of Canterbury, 3rd August, 1898.]
Plate II. (in part).
I Wish to make the following corrections and additions to my paper on the Stenopelmatidœ, published in the twenty-ninth volume of the “Transactions of the Zealand Institute”:—
There is a mistake in the synopsis of the genus Pleioplectron. It should read as follows, now that P. diversum is left out:—
“Fore femora with one and middle femora with two apical spines. Fore and middle tibiæ with two pairs of apical spines; hind tibiæ with three pairs, of which the superior is much the longer.”
The words “hind tibiæ with three pairs” were, unfortunately, omitted.
Talitropsis sedilotti (page 225).
I have received a female of this species from Makaretu, in Hawke's Bay, collected by Mr. W. F. Howlett, which differs slightly from my description of those from the South Island, which was taken from males. The inferior margins of the lobes of the pronotum do not descend posteriorly, and the lobes of the meso- and meta-nota are rounded. The small spines on the upper surface of the hind tibiæ alternate with the larger ones, so that there are only two (not four) rows. The second joint of the hind tarsi is not less than half the first. Seventh abdominal segment below with two short spines. Subgenital plate notched at the end.
Colours.—Tawny, paler below, variegated “with brown on the back and sides; a pale band down the centre of the prornotum; knees, tibiæ, and tarsi of the hind legs brown; ovipositor getting brown towards the apex.
Length, 18 mm; pronotum, 5 mm; thorax, 10 mm.; abdomen, 10 mm.; ovipositor, 12 mm.; antenna, 72 mm.; fore tibia, 8 mm.; hind tibia, 13 ½ mm.; hind femur, 13 ½ mm. Width of mesonotum, 5 ½ mm.
The following is a key to the species:—
|Spines on the hind tibiæ of two sizes||T. sedilotti.|
|Spines on the hind tibiæ of one size.|
|Spines, 8 or 9||T. crassicruris.|
|Spines, 13||T. irregularis.|
Pachyrhamma novæ-seelandiæ (page 232).
Brunner's figure shows spines on the middle femora, although no mention is made of them in the text.
Pachyrhamma fascifer (page 232).
In the third line of the description, for “fore tibiæ” read “middle tibiæ.”
Pleioplectron diversum (page 235).
I have received from Mr. W. F. Howlett, of Makaretu, Hawke's Bay, a male specimen of this species, which shows that it cannot be kept in Pleioplectron, as the supra-anal and subgenital plates are very different, but must be placed in a new genus, for which. I propose the name “Miotopus.”
Miotopus, gen. nov.
Fore and middle femora with two short apical spines, those on the middle femora longer. Middle tibiae armed with spines on the upper surface. Supra-anal plate of the male transverse, the apex truncated and without any point; the cerci rather long and slender. Subgenital plate of the male longer than broad, rounded at the apex, the styles very short and situated near the apex. The rest as in Pleioplectron.
Miotopus diversus. Plate II., figs, 1a, 1b.
Pleioplectron diversum, Hutton, Trans. N.Z. Inst., vol. xxix., p. 235.
Male.—The antennæ are thicker than in the female. The middle tibiæ have two or three spines on the upper surface. Length, 20 mm.; of pronotum, 5 mm.; of thorax, 9 mm.; of abdomen, 10 mm.; of fore tibia, 10 mm.; of hind tibia, 18 mm.; of hind femur, 16 mm. Width of mesonotum, 5 mm.
Locality.—Makaretu, Hawke's Bay (W. F. Howlett).
Macropathus edwardsii (page 240).
Mr. Scudder has kindly re-examined the type of this species for me, and finds that it does not agree with Brunner's description, of what he thought to be H. edwardsii, nor does it belong to Macropathus, as I supposed it might do, but to Pleioplectron. He informs me that “the fore femora have an apical spine on the outer side only, the middle femora on both sides, and the
hind femora have none. The fore and middle tibiæ have a pair of apical spines on each side, the lower of which are longer, but not to a great degree. The spines on the upper surface of the hind tibiæ are of two grades, and more or less irregular. The longest spurs at the end of the hind tibiæ are the middle pair. The apical spines of the femora are testaceous, deepening apically in colour to reddish fuscous, and are about half as long as the width of the genicular lobes from which they spring.
The following is a key to the species of Pleioplectron :—
|Hind femora with two minute spines below; hind tibiæ less than five times the length of the pronotum.|
|Hind tibiæ less than three times the length of the pronotum.|
|Proximal joints of the antennæ rather broader than long||P. simplex.|
|Proximal joints of the antennæ much broader than long||P. pectinatum.|
|Hind tibiæ more than three times the length of the pronotum||P. hudsoni.|
|Hind femora unarmed below; hind tibiæ more than six times the length of the pronotum||P. edwardsii.|
It is remarkable that our cave-wetas should belong to three different endemic genera—omitting the doubtful Hemideina abbreviata. Cave-wetas belonging to other genera are known in North America, Europe, and Burmah, and all, as well as our own, belong to the Dolichopodinœ, distinguished by having no foot-pads. In our genera, Macropathus is closely allied to Pharmacus, which lives on the mountains, both being known at present only from the South Island; Pachyrhamma is allied to Gymnoplectron, which lives among the branches of trees, both genera being known at present only from the North Island; Pleioplectron has, in the South Island, one cave species and two which live among rotten wood, and one outdoor species in the North Island. Now, we cannot suppose that the immediate ancestors of our cave-wetas lived in caves during their migration into New Zealand, partly because of the physical impossibility of their having passed from one cave to another, and partly because each is closely allied to other species which do not live in caves. Macropathus and Pleioplectron may have originated from a common ancestor in New Zealand; but Pachyrhamma is more nearly related to European and American forms, and its original ancestors in New Zealand must have been distinct from those of Pleioplectron. We must therefore, I think, conclude that our first immigrant Dolichopodinœ did not live in caves, but that some of their descendants have, like their remote northern ancestors, taken to that curious mode of life. If this be true, we have here a most remarkable example of the resuscitation
of a habit which must have remained dormant or latent through many generations. It is well known that. physical characters may remain latent for an unknown number of generations, but this is, I believe, the most remarkable case yet recorded of latent psychological characters.
Correotions in the Plates (page 241).
Fig. 4b. The sounding-organs axe not shown in the figure.
Fig. 5b. Should be “Onosandrus focalis, side view, showing sounding-organs.”
Fig. 5c. Should be omitted.
Fig. 5d. Should be “Onosandrus focalis, sternum.”
Fig. 13a. Should end in a point, not in a slit. The slit was intended to represent a keel.
Fig. 15. Should be “Pleioplectron hudsoni, supra-anal plate of male.”
Mr. W. F. Kirby, of the British Museum, has kindly looked over Walker's types, and sends me the following notes:—
Deinacrida heteracantha, White.—Perhaps distinct from D. gigantea.
Hemideina thoracica, White.—The type has distictly four spines in each row of the hind tibiæ. H. capitolina, H. figurata, H. producta, H. abbreviata,. and H. tibialis all appear to belong to H. thoracica.
Hemideina armiger, Colenso.—The same as D. thoracica, of Brunner.
Onosandrus lanceolatus, Walker (Ceuthophilus).—Appears to be a dark uniformly coloured specimen of O. pallitarsis.
Pachyrhamma fascifer, Walker.—This appears to be P. speluncœ.
Pachyrhamma altus, Walker.—Seems to agree with P. novœ-zealandiœ.
Macropathus species, from Auckland.—Larger than M. filifer, and with much more numerous and conspicuous teeth on the hind femora beneath.