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Revision of the Rhaphidophoridae (Orthoptera) of New Zealand—Part V.
The Genus Pleioplectron Hutton, 1897

[Received by the Editor, April 24, 1959.]

Abstract

The genus Pleioplectron Hutton is redefined and a key is given to the genus. Three species, Pleioplectron simplex Hutton, P. pectinatum Hutton and P. diversum Hutton, are redefined and the synonymy of the latter discussed. P. hudsoni Hutton is mentioned. P. edwardsii (Scudder) is tentatively left in the genus Pleioplectron. P cavernae Hutton is placed in the genus Pachyrhamma Brunner.

Introduction

The genus Pleioplectron Hutton consists primarily of bush-dwelling members of the subfamily Macropathinae, the only cave-dwelling species so far recorded being P. edwardsii (Scudder). Most of the species described inhabit rotten wood. The genus has been recorded from both the North and South Islands of New Zealand. In all, Hutton placed seven species in his genus, and these species are now re-examined and their synonymy discussed.

Genus Pleioplectron. Hutton, 1897
  • 1897. Pleioplectron Hutton, Trans. N.Z. Inst., 29: 232–233.

  • 1899. Miotopus Hutton, Trans. N.Z. Inst., 31: 41.

In 1897, Hutton erected the genus Pleioplectron and placed in it four new species, Pleioplectron simplex, P. hudsoni, P. pectinatum and P. diversum. Two years later he added Macropathus edwardsii (Scudder) to the genus as P. edwardsii (Scudder), and placed P. diversum in a new genus as Miotopus diversum (Hutton). In 1900, he described a new species as P. cavernae.. Finally, in 1904, he added a new species from the Chatham Islands as P. serratum. This species has been placed in a new genus by the author as Novoplectron serratum (Hutton) (Richards, 1958a).

Hutton's original material of the type species for the genus has been examined by the author, and has been found to differ from Hutton's generic description. He described the fastigium as sulcate instead of convex. He says the hind femora are without apical spines, when they possess a prolateral apical spine beneath. According to Hutton, the hind tibiae are armed with three pairs of apical spines, while re-examination shows they possess four pairs. His description of the genitalia is also inaccurate. He describes the supra-anal plate of the male as “transverse, the apex truncated, with a small point in the middle”, whereas it is trilobed, the two outer lobes each tapering to a point, while the median lobe is rounded. The subgenital plate of the male he describes as “longer than broad, cuspidate, terminating in an acute point between the styles” when it is subequal in length to width, trilobed distally, with the median lobe pointed and strongly keeled. Of the subgenital plate of the female he says, “apex with three points”. While this is the case in P. diversum, in P. simplex, the type species for the genus, it is produced into two rounded lobes separated by a widely emarginate area.

Transactions of the Royal Society of New Zealand Vol. 87, Parts 3 and 4, pp. 319–327, 3 Text-figs, November, 1959

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The genus Pleioplectron Hutton therefore must now be redefined as follows:—

Body clothed with numerous short setae. Legs long and slender. Antennae very long and tapering, almost touching at their bases; scape about four times as large as pedicel, which is narrower than scape, but broader than other segments; from fourth segment onwards segments subequal, although steadily decreasing in size; all segments thickly clothed with short setae. A single anterior, median ocellus only. Fastigium rising abruptly, convex, ridged medianly and longitudinally. Maxillary palps with third and fourth segments subequal in length. All femora sulcate ventrally. No linear spines occur on fore or middle femora and tarsi. Apical spines on femora, tibiae, first and second proximal segments of hind tarsi constant in number. Fore femur bears one apical spine beneath prolaterally; fore tibia bears four apical spines, one above and one beneath both prolaterally and retrolaterally; fore tarsus unarmed. Middle femur bears two apical spines beneath, one prolateral and the other retro-lateral; middle tibia bears four apical spines, one above and one beneath, both prolaterally and retrolaterally; middle tarsus unarmed. Hind femur bears one apical spine beneath prolaterally; hind tibia bears a pair of long apical spurs above, a pair of subapical spines above, a pair of short apical spurs beneath and a pair of subapical spines beneath, one from each pair being prolateral and the other retrolateral; two proximal segments of hind tarsus each bear two apical spines above, one prolateral and one retrolateral; other two segments unarmed. Subgenital plate of female two or three-lobed. Subgenital plate of male trilobed distally, the median lobe being keeled. Latero-medianly the plate bears two styli, one to each side.

Type species for the genus: Pleioplectron simplex Hutton.

Key To The Species of Pleioplectron

1. Hind tibiae with over 20 linear spines 2
Hind tibiae with up to 12 linear spines P. hudsoni Hutton
2. Hind femora with up to three linear spines 3
Hind femora without linear spines P. edwardsii (Scudder)
3. Middle tibiae unarmed above 4
Middle tibiae with linear spines above P. diversum Hutton
4. Three lobes of subgenital plate of male pointed and subequal in length P. simplex Hutton
Two outer lobes of subgenital plate of male rounded and longer than median lobe P. pectinatum Hutton

Because of the paucity of material available for examination, in some cases the original descriptions alone have been used, this key will need revising after further specimens become available for study.

Pleioplectron simplex Hutton, 1897. Text-fig. 1, figs. 1–4.

  • 1897. Pletoplectron simplex Hutton, Trans. N.Z. Inst., 29: 233–234.

Hutton described the species Pleioplectron simplex from eight co-types, six males and two females, collected from among dead wood in North Canterbury and Banks Peninsula. Fortunately the original material is still available for examination and has been studied by the author. There are several points in which Hutton's description differs from the actual specimens. Describing the spination of the hind tibia, he says there are “about seventeen in the inner (posterior) row”, whereas the range for the eight specimens is between 22–32. The subgeintal plate in both male and female does not agree with Hutton's description and illustrations. In the male the plate is subequal in width to length, not “longer than broad”; and trilobed, not “triangular”. In the female the plate consists of two lobes with a widely emarginate space between them, not of “three apical points … nearly in the same line”. The length of the ovipositor is 8 mm, not 11 mm.

Because of the inadequacy of Hutton's description, the species Pleioplectron simplex is now redescribed as follows:—

Colour. Basic colour ochreous, with pronotum, mesonotum, metanotum and abdominal terga irregularly mottled with light brown; posterior borders light brown, femora and tibiae ochreous, banded with light brown; hind femora with colour pattern poorly defined in ochreous and light brown; tarsi ochreous; antennae light brown; ovipositor reddish-brown.

Body. Length up to 16 mm in male, and 14 mm in female. Ovipositor 0.6 as long as body. Antennae broken. Pronotum truncated anteriorly and posteriorly; pronotum margined anteriorly and laterally, mesonotum margined laterally.

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Antennae. As in generic description. Third segment narrower than pedicel, on dorsal aspect subequal in length with pedicel in male, and 1.7 as long as pedicel in female; on ventral aspect 0.8 as long as pedicel in male, and 1.2 as long as pedicel in female. Sexual dimorphism well developed, male possessing much longer, stouter antennae than female; no spines present on flagellum of male or female.

Legs. Long and slender. Fore and middle legs subequal in length, with hind leg 1.5 length of fore and middle legs in male, and 1.7 length of fore and middle legs in female. Sexual dimorphism is shown by fore legs of female being 0.7 as long as those of male; middle legs of female 0.8 as long as those of male; and hind legs of female 0.8 as long as those of male. Femora, tibiae and two proximal segments of hind tarsi armed with variable number

Picture icon

Text-fig. 1.—Pleioplectron simplex Hutton. Fig. 1—Female genitalia, dorsal view. Fig. 2.— Female genitalia, ventral view. Fig. 3.—Male genitalia, dorsal view. Fig. 4.—Male genitalia, ventral view.

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[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

Table. I—Variability in Number of Linear Spines on the Legs of 8 Specimens of Pleioplectron Simplex Hutton.
Arith. Mean Std. Dev. Range.
L. R. L. R. L. R.
Fore Femur Pro. 0 0 0 0 0 0
Inf. Retro. 0 0 0 0 0 0
Fore Tibia Pro. 2.9 3 - 0 2(1), 3(7) 0
Inf. Retro. 3 3 0 0 0 0
Fore Tarsus Pro. 0 0 0 0 0 0
Retro. 0 0 0 0 0 0
Mid. Femur Pro. 0 0 0 0 0 0
Inf. Retro. 0 0 0 0 0 0
Mid Tibia Pro. 0 0 0 0 0 0
Sup. Retro. 0 0 0 0 0 0
Mid. Tibia Pro. 2.5 2.5 2 (4), 3 (4) 2 (4), 3 (4)
Inf. Retro. 3 2.9 3(8) 2(1),3(7)
Mid. Tarsus Pro. 0 0 0 0 0 0
Retro. 0 0 0 0 0 0
Hind Femur Pro. 2.1 2.7 0 0 2(6),3(1) 2(2),3(5)
Inf. Retro. 0 0 0 0 0 0
Hind Tibia Pro. 25.6 27.7 1.7 2.6 22–27 25–32
Sup. Retro. 25.7 27.3 1.5 1.6 24–28 24–29
Hind Tarsus Pro. 3.4 3.9 1.4 0.7 1–5 3–5
1 Sup. Retro. 3.6 3.3 1.0 0.5 2–5 3–4
Hind Tarsus Pro. 1.4 1.6 1 (4), 2 (3) 1 (3), 2 (4)
2 Sup. Retro. 1.6 1.4 1 (3), 2(4) 1 (4), 2 (3)

Figures in parentheses represent number of specimens

of linear spines (Table I). No spines occur on fore and middle femora and tarsi. Apical spines constant in number, as in generic description. First segment of hind tarsus longer than other three together. Ratio of length of legs to length of body—Fore leg: male, 1.4:1, female, 1.2:1. Middle leg: male, 1.3:1, female, 1.2:1. Hind leg: male, 2.2:1, female, 2.1:1.

Genitalia. Female: Suranal plate, Fig. 1 (SAP), with lateral margin slightly rounded and tapering to a rounded apex distally; margin bears a row of setae; rest of plate sparsely clothed with setae. Subgenital plate, Fig. 2 (SGP), 3.4 wider than long; rounded laterally; distally the plate is produced into two rounded points, widely emarginate between; whole plate clothed with setae. Male: Suranal plate, Fig. 3 (SPL), sides convex proximally, notched 0.7 from proximal end; distally the plate is trilobed, the two outer lobes each tapering to a point, while the median lobe is rounded; two outer lobes thickly clothed with setae; rest of plate sparsely clothed with setae. Subgenital plate (hypandrium), Fig. 4 (H), subequal in length to width. Lateral margin convex. Distally between the insertion of the styli the plate is trilobed, the median lobe being pointed at the apex and strongly keeled; with lateral lobes less strongly pointed and thickly clothed with setae; rest of plate sparsely clothed with setae. Subgenital plate completely covers gemtalia. Disto-laterally it bears two styli (S), one on each side, thickly clothed with setae, length of styli being 0.4 length of sternite IX. Parameres, Figs. 3, 4 (P), attenuated, broad at base and tapering to a rounded apex. Penis not visible. Paraprocts, Fig. 4 (PP), short, broader than long.

Localities. North Canterbury (type locality) and Banks Peninsula, among dead wood.

Types. Lectotype male and paratype male and female in Canterbury Museum Collection.

Pleioplectron hudsoni Hutton, 1897.

  • 1897. Pletoplectron hudsoni Hutton, Trans. N.Z. Inst., 29: 234.

Pleioplectron hudsoni was described by Hutton from a single male specimen collected in Wellington by G. V. Hudson, after whom the species was named.

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The female remains unknown, and no further specimens of this species have been collected since. Unfortunately the type material is lost, and the paucity of description and illustrations will make it very difficult to recognise this species again.

Pleioplectron pectinatum Hutton, 1897. Text-fig. 2, figs. 1–2.

  • 1897. Pleioplectron pectinatum Hutton, Trans. N.Z. Inst., 29: 234.

Pleioplectron pectinatum was described by Hutton from two male specimens collected from Banks Peninsula. The female of this species is still unknown. Only one specimen is available today for examination, and it is in a rather poor state of preservation. However, from this specimen it is possible to detect several points of difference from Hutton's description. There is probably a printing error in the third line of his description which says, “Fore and hind femora unarmed below; hind femora, below, with two minute spines”. The first “hind femora” the author takes to be middle femora, as this agrees with the actual specimen. Of the tibiae he says, “Fore and middle tibiae with two spines in each row below, none above”. In the specimen the fore tibiae have three prolateral and three retrolateral spines below, and the middle tibiae two prolateral and three retrolateral spines below. Of the hind tibia he says, “with about twenty-five spines in each row” whereas there are really twenty-seven or twenty-eight. He did not record the thick clothing of setae on the antennae, but described them as “sparingly covered with hairs”. According to Hutton the subgenital plate is “transverse, with a narrow keel ending in a point”. Re-examination of the specimen shows it to be trilobed distally, the median lobe being keeled. The length of the body is 12 mm, not 15 mm as stated by Hutton, but this may be due to shrinkage of the specimen in alcohol. Since Hutton's time no further specimens of this species have been collected.

Because of the inaccuracies in Hutton's description and his lack of detail, the species Pleioplectron pectinatum is redefined as follows:—

Colour. Basic colour light brown, with pronotum, mesonotum and metanotum mottled with medium brown; abdominal terga mottled with ochreous; fore and middle femora and tibiae banded with ochreous; hind femora with colour pattern poorly defined in medium brown and ochreous; hind tibiae medium brown; tarsi deep ochreous; antennae light brown.

Body. Length, 12 mm. Antennae broken. Pronotum truncated anteriorly and posteriorly; pronotum margined anteriorly and laterally, mesonotum margined laterally.

Antennae. As in generic description. Third segment narrower than pedicel, on dorsal aspect 1.2 as long as pedicel, and on ventral aspect 0.8 as long as pedicel. No spines present on flagellum.

Picture icon

Text-fig. 2 —Pleioplectron pectinatum Hutton. Fig. 1—Male genitalia, dorsal view. Fig. 2—Male genitalia, ventral view.

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Legs. Long and slender. Fore and middle legs subequal in length, with hind leg 1.7 length of fore and middle legs. Femora, tibiae and two proximal segments of hind tarsi armed with variable numbers of linear spines. Fore femur unarmed; fore tibia bears three prolateral and three retrolateral inferior linear spines; fore tarsus unarmed. Middle femur unarmed; middle tibia bears two prolateral and three retrolateral inferior linear spines; fore tarsus unarmed. Middle femur unarmed; middle tibia bears two prolateral and three retrolateral inferior linear spines; middle tarsus unarmed. Hind femur bears two prolateral inferior linear spines; hind tibia bears twenty-seven or twenty-eight prolateral and twenty-seven or twenty-eight retrolateral superior linear spines; proximal segment of hind tarsus bears three or four prolateral and five retrolateral superior linear spines; second segment of hind tarsus bears two prolateral and two retrolateral superior linear spines. Apical spines constant in number, as for generic description. First segment of hind tarsus equal in length with other three segments together. Ratio of length of legs to length of body: fore leg, 1.7:1; middle leg, 17:1; hind leg, 2.8:1.

Genitalia. Male: Suranal plate, Fig. 1 (SPL), sides convex proximally, notched 0.57 from proximal end; distally the plate is trilobed, each lobe rounded apically; three lobes thickly clothed with setae; rest of plate sparsely clothed with setae. Subgenital plate (hypandrium), Fig. 2 (H), 1.3 wider than long. Lateral margin convex. Distally between the insertion of the styli the plate is trilobed, the median lobe being pointed at the apex and strongly keeled; with lateral lobes longer, rounded and thickly clothed with setae; proximal portion of plate thickly clothed with setae, more distal portion of plate sparsely clothed with setae. Subgenital plate covers genitalia. Disto-laterally it bears two styli (S), one on each side, thickly clothed with setae, length of styli being 0.5 length of sternite IX. Pseudosternite, Figs. 1, 2 (PD), wider than long, convex laterally, tapering to concave proximo-distally with a rounded apex; on dorsal surface it is curved back on itself for a short distance.

Locality. Banks Peninsula (type locality).

Types. Lectotype male in Canterbury Museum Collection. Female unknown.

Pleioplectron diversum Hutton, 1897. Text-fig. 3, figs. 1–2.

  • 1897. Pletoplecton diversum Hutton, Trans, N.Z. Inst., 29: 235.

  • 1899. Miotopus diversus (Hutton), Hutton, Trans. N.Z. Inst., 31::41.

In 1897 Hutton added another new species to his genus Pleioplectron as P. diversum. It was described from a single female specimen collected by S. H. Drew from Upper Wanganui. The original material has been examined by the author and compared with Hutton's description, from which it differs in a number

Picture icon

Text-fig. 3 —Pleioplectron diversum Hutton. Fig. 1—Female genitalia, dorsal view. Fig. 2—Female genitalia, ventral view.

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of points. Hutton says, “All the femora unarmed below”, whereas the hind femur possesses one prolateral inferior linear spine. He says, “Middle tibiae … above, armed with a row of four spines”, while there are three retrolateral superior linear spines and four or five prolateral superior linear spines. The linear spines on the hind tibiae range between twenty-six and twenty-eight and are not “twenty-five in each row”. The first joint of the hind tarsus is slightly, not “considerably” longer than the other three together. Finally, the three distal apices on the subgenital plate are subequal in length, not with “the middle one projecting much beyond the laterals.”

At the end of the description Hutton added a note saying that the two spines on the fore femora placed the species in the genus Neonetus Hutton, but the apical spines of the fore and middle tibiae and the subgenital plate of the female showed it was nearer to Pleioplectron. He considered the spines on the upper surface of the middle tibiae as very unusual.

In 1899, Hutton published a further note on P. diversum. He claimed to have received a male specimen of P. diversum collected by W. F. Howlett from Makaretu, Hawke's Bay. Because of the structure of the male external genitalia, he considered that the species diversum must be placed in a new genus, for which he proposed the name Miotopus. Unfortunately this specimen is lost. The type localities of the male and female are widely separated. Admittedly the presence of two apical spines on the fore femora is a different character to that found in Pleioplectron; but variation is so common that too much weight cannot be placed on it when only one specimen is available for examination. The presence of superior linear spines on the middle tibiae could be a purely specific character. The general form of the insect and the shape of its genital plates certainly place it in Pleioplectron. Till further specimens of this species can be examined, the author feels it more correct to place the species diversum back in the genus Pleioplectron and sink the genus Miotopus in synonymy.

The species Pleioplectron diversum is now redefined as follows:—

Colour. Basic colour light brown, with pronotum, mesonotum, metanotum and abdominal terga irregularly mottled with medium brown and dark ochreous; posterior borders medium brown; femora and tibiae light brown banded with dark ochreous; hind femora with colour pattern poorly defined in medium brown, light brown and ochreous; tarsi dark ochreous; antennae light brown; ovipositor reddish-brown.

Body. Length, 16 mm. Ovipositor 0.7 as long as body. Antennae broken. Pronotum rounded anteriorly and posteriorly; pronotum, mesonotum and metanotum margined laterally.

Antennae. As in generic description. Third segment narrower than pedicel, on dorsal aspect 0.2 as long again, and on ventral aspect 0.3 as long again. No spines on flagellum.

Legs. Long and slender, thickly clothed with setae. Fore and middle legs subequal in length, with hind leg 1.8 length of fore and middle legs. Femora, tibiae and two proximal segments of hind tarsi armed with variable number of linear spines. Fore femur unarmed; fore tibia bears three retrolateral and two prolateral inferior linear spines; fore tarsus unarmed. Middle femur unarmed; middle tibia bears retrolaterally three inferior and three superior linear spines and prolaterally three inferior and four or five superior linear spines; middle tarsus unarmed. Hind femur bears one prolateral inferior linear spine; hind tibia bears twenty-six or twenty-seven retrolateral and twenty-six to twenty-eight prolateral superior linear spines; proximal segment of hind tarsus bears three or four retrolateral and three prolateral superior linear spines; second segment of hind tarsus bears one retrolateral and one prolateral superior linear spine. Apical spines differ from generic description in having a prolateral and retrolateral apical spine on fore femora. First segment of hind tarsus slightly longer than other three together. Ratio of length of legs to length of body: fore leg, 1.3:1; middle leg, 1.3:1, hind leg, 2.2:1.

Genitalia. Female: Suranal plate, Fig. 1 (SAP), with lateral margin slightly convex, truncated distally; distal margin bearing two groups of setae, rest of plate sparsely clothed with setae. Subgenital plate, Fig. 2 (SGP), 4.5 wider than long; distal margin serrated, with three points subequal in length; whole plate sparsely clothed with setae.

Locality. Upper Wanganui (type locality), coll. S. H. Drew.

Types. Holotype female in Canterbury Museum Collection. Known from one specimen only; male unknown.

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Pleioplectron edwardsii (Scudder, 1869).

  • 1869. Hadenoecus edwardsii Scudder, Ent. Notes Proc. Bost. Soc. Nat. Hist., 12: 408–409.

  • 1897. Macropathus edwardsii (Scudder), Hutton, Trans. N.Z. Inst., 29: 240.

  • 1899. Pleioplectron edwardsii (Scudder), Hutton, Trans. N.Z. Inst., 31: 41.

  • 1958. Pleioplectron edwardsii (Scudder), Richards, Trans. Roy. Soc. N.Z., 85: 467–468.

In 1869, Scudder described a new species of Rhaphidophoridae from New Zealand as Hadenoecus edwardsii. He named it after its collector, Mr. Henry Edwards, who had captured one imperfect specimen from a limestone cave at Collingwood.

When Hutton wrote his paper “The Stenopelmatidae of New Zealand” in 1897, he redefined Walker's genus Macropathus and placed Scudder's species Hadenoecus edwardsii in it as Macropathus edwardsii (Scudder). He commented, “I have not seen this species, but the absence of spines from the hind femur and its great length of leg seem to distinguish it”. (Scudder's very inadequate description makes no mention of the spination of the legs.)

Hutton afterwards doubted the validity of this species as he asked Scudder to re-examine the type material for him. Scudder replied that the species did not belong to Hutton's genus Macropathus (nec Walker), but to Pleioplectron on the basis of the apical spination of the legs. Hutton then published a note in 1899 placing the species edwardsii Scudder in the genus Pleioplectron as P. edwardsii (Scudder).

Unfortunately Hutton inacurately described the genus Pleioplectron as having no apical spines on the hind femora and three pairs of apical spines on the hind tibiae. These characters Scudder confirmed in his specimen. Thus it is doubtful if the species edwardsii really belongs in the genus Pleioplectron, and further examination of Scudder's type material is necessary to give accurate determination. In the meantime the species is tentatively left in the genus Pleioplectron.

Pleioplectron cavernae Hutton, 1900.

  • 1900. Pleioplectron cavernae Hutton, Trans N.Z. Inst., 32: 21.

  • 1900. Pachyrhamma edwardsii (Scudder), Brunner, Monog. Steno. Gryll. Verh. z-b Gesellsch. Wien, 38: 302.

  • 1923. Pleioplectron cavernae Hutton, Chopard, Trans. N.Z. Inst., 54: 234.

  • 1930. Pleioplectron cavernae Hutton, Karny, Ann. Nat.-Hist. Mus. Wien, 44: 182–185.

  • 1959. Pleioplectron cavernae Hutton, Richards, Trans. Roy. Soc. N.Z. 86: 27–29.

In 1900, Hutton described another new species as Pleioplectron cavernae, claiming it to be “easily distinguished from the others belonging to the genus by the greater number of spines on the lower surface of the hind femur”. The species was described from four males and two females collected by R. M. Laing from a small cave near Karapiti fumerole, Taupo. As has been mentioned in a previous paper (Richards, 1959) most of Hutton's original material has been lost, an immature and badly damaged male and female in the British Museum (Nat. Hist.) Collection being all that remain. Unfortunately no further specimens of this species have been collected.

When Hutton described P. cavernae, without giving any reasons, he synonymised Pachyrhamma edwardsii (Scudder) Brunner with it. As has been shown in a previous paper (Richards, 1959) the author has been able to examine the type material of both species and prove that they are really two distinct species in no way related.

Through the courtesy of Dr. D. R. Ragge, of the British Museum (Nat. Hist.), the author has been able to study Hutton's material of Pleioplectron cavernae and is of the opinion that, although the specimens are immature and damaged, they do not belong to the genus Pleioplectron, but are closely related to the genus Pachyrhamma Brunner. The shape of the genital plates in particular are similar to Pachyrhamma. The main point of difference from Pachyrhamma is the absence

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of a retrolateral apical spine on the hind femora. On the basis of this, and until further material is available for more detailed examination, the author now removes the species cavernae from the genus Pleioplectron Hutton and tentatively places it in the genus Pachyrhamma Brunner as Pachyrhamma cavernae (Hutton).

Acknowledgments

I should like to thank Dr. R. R. Forster, formerly Assistant Director of the Canterbury Museum and now Director of the Otago Museum, and Mr. E.G. Turbott, now Assistant Director of the Canterbury Museum, for the loan of Hutton's type material of Pleioplectron simplex, P. pectinatum and P. diversum; and Dr. D. R. Ragge, curator of Orthoptera at the British Museum (Nat. Hist.), for permission to examine Hutton's specimens of Pleioplectron cavernae. I should like also to thank Dr. H. R. Thompson, of the Applied Mathematics Laboratory, for assistance in preparing the table.

Literature Cited

Brunner von Wattenwyl, C., 1888. Monographie der Stenopelmatiden und Gryllacriden. Verh. k.k. Zool. und Bot. Gesellsch. Wien.38: 247–394 (see p. 302).

Chopard, L, 1923. On Some New Zealand Cave Orthoptera.Trans. N.Z. Inst., 54: 230–239.

Hutton, F. W., 1897. The Stenopelmatidae of New Zealand. Trans. N.Z. Inst., 29: 223–240.

— 1899. Supplement to the Stenopelmatidae of New Zealand. Trans. N.Z. Inst., 31: 40–43.

— 1900. Notes on Some New Zealand Orthoptera. Trans. N.Z. Inst., 32: 21.

— 1904. On a New Weta from the Chatham Islands.Trans. N.Z. Inst., 36: 154.

Karny, H. H., 1930 Revision der Gryllacriden des Naturhistorischen Museums in Wien emschliedlich der Collection Brunner v. Wattenwyl. Ann. Nat.-Hist. Mus. Wien, 44: 182–185.

Richards, Aola M., 1958a. Revision of the Rhaphidophoridae (Orthoptera) of New Zealand Part 1. The Rhaphidophoridae of the Chatham Islands 1954 Expedition. Trans. Roy. Soc. N.Z., 85: 263–274.

— 1958b. Revision of the Rhaphidophoridae (Orthoptera) of New Zealand. Part II The Genus Macropathus Walker in the British Museum (Nat. Hist.) Collection Trans. Roy. Soc. N.Z., 85: 465–470.

— 1959. Revision of the Rhaphidophoridae (Orthoptera) of New Zealand. Part IV. The Rhaphidophoridae of the Thames Gold-mines. Trans. Roy. Soc. N.Z., 86: 27–33.

Scudder, S. H., 1869. A New Cave Insect from New Zealand. Proc. Bost. Soc. Nat. Hist., 12: 408–409.

Dr. Aola M. Richards

,
Plant Diseases Division,
Department of Scientific and Industrial Research,
Private Bag, Auckland.

Index to Text-figures
  • B—basivalvula.

  • BC—basal segment of cercus.

  • C—cercus.

  • DV—dorsal valve.

  • H—hypandrium (subgenital plate of male).

  • IA—intersegmental apodeme.

  • MT IX—membrane tergite IX.

  • P—paramere.

  • P VII, P VIII, P IX—pleurite VII, VIII, IX.

  • PD—pseudosternite.

  • PM—perianal membrane.

  • PN—penis.

  • PP—paraproct.

  • S—stylus.

  • SAP—suranal plate, female.

  • SGP—subgenital plate, female.

  • SPL—suranal plate, male.

  • S VII, S VIII, S IX—sternite VII, VIII, IX.

  • T VII, T VIII, T IX, T X—tergite VII, VIII, IX, X.

  • 1 VF—first valvifer.

  • 2 VF—second valvifer.

  • VV—ventral valve.

Index to Table I.

  • Arith. mean—Arithmetic mean.

  • Std. Dev.—Standard Deviation.

  • Prol.—Prolateral.

  • Retrol.—Retrolateral.

  • Inf.—Inferior.

  • Sup.—Superior.

  • Mid.—Middle.

  • L.—Left leg.

  • R.—Right leg.