Systematics of Megachiropteran Bats in the Solomon Islands - Part 5
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Part 5

1860. _Pteropus geddiei_ MacGillivary, Zoologist, 18:7134, September, type from Aneitum Island, New Hebrides; 1912, Andersen, Catalogue of the Chiroptera ... British Museum, 1:189; 1931, Sanborn, Publ. Field Mus. Nat. Hist., Zool.

Ser., 18:13, February 12, from Rennell Island in the Solomons.

1914. _Pteropus tonga.n.u.s geddiei_, Revilliod, _in_ Sarasin and Roux, Nova Caledonia (A), 1:341; 1954, Laurie and Hill, List of land mammals of New Guinea, Celebes and adjacent islands, p. 34, June 30.

_Specimens examined._--None.

_Remarks._--_Pteropus tonga.n.u.s geddiei_, as far as is known, is the widest ranging subspecies of this genus. It is the only megachiropteran in the Solomon Islands having affinities with bats to the southeast (the New Hebrides, Santa Cruz Islands, Samoan Islands and Fiji Islands) rather than with those to the west (New Guinea). The subspecies _P.

tonga.n.u.s geddiei_, which ranges from the Solomons to the New Hebrides (about 500 miles straight-line distance), is said to be remarkably uniform throughout its range. Sanborn (1931:14) compared color and size in specimens from the Solomon Islands and the New Hebrides and found little variation. Another subspecies, _P. t. bascilicus_ Thomas 1915, apparently closely related to _geddiei_, is known from Dampier [= Kar-kar] Island off the northeastern coast of New Guinea and therefore farther westward from the New Hebrides than are the Solomon Islands.

Additional remarks on the distribution of this species are in the section on Zoogeography and Speciation.

=Pteropus rayneri=

_Pteropus rayneri_ is endemic to the Solomon Islands. It is divisible into seven subspecies (see Fig. 6), which, excepting _P. r. rennelli_ and _P. r. cognatus_, are strikingly colored--the mantle, back, and rump being of different colors. Differences in color and size provide characters differentiating the subspecies (see key, p. 793). Recorded lengths of forearms do not overlap between any two subspecies. _P. r.

grandis_, northernmost in distribution, has the longest (about 170) forearm and _P. r. cognatus_, known from two of the southernmost islands, has the shortest (about 121).

[Ill.u.s.tration: FIG. 6. Distribution of _Pteropus rayneri_: _P. r.

rayneri_ ([RTW]); _P. r. grandis_ ([RW]); _P. r. lavella.n.u.s_ ([BC]); _P. r. monoensis_ ([BW]); _P. r. rubia.n.u.s_ ([TW]); _P. r. cognatus_ ([LW]); _P. r. rennelli_ ([LTW]). For names of islands see Fig. 2.]

Adult males of _Pteropus rayneri_ have well-developed tufts of hair on each side of the neck where a gland is located (see Andersen, 1912:259). Apparently these glands are not present in females as none were found in specimens studied by me or those reported by Sanborn (1931:16). Evidently, these glands are a.s.sociated with s.e.xual maturity in males because neither Sanborn nor I found them in subadult males.

=Pteropus rayneri rayneri= Gray

1870. _Pteropus rayneri_ (part), Gray, Catalogue of monkeys, lemurs and fruit-eating bats ... British Museum, p. 108, cotypes from Guadalca.n.a.l; 1878, Dobson, Catalogue of the Chiroptera ...

British Museum, p. 33; 1879, Trouessart, Rev. Mag. Zool., 6:204; 1879, Trouessart, Ann. Sci. Nat. Zool, 8:16; 1887, Thomas, Proc.

Zool. Soc. London, p. 322, March 15; 1888, Thomas, Proc. Zool.

Soc. London, p. 472, December 4; 1898, Trouessart, Catalogus Mammalium ..., 1:78; 1912, Andersen, Catalogue of the Chiroptera ... British Museum, p. 254; 1931, Sanborn, Publ. Field Mus. Nat.

Hist., Zool. Ser., 18:15, February 12, from Guadalca.n.a.l and Malaita.

1954. _Pteropus rayneri rayneri_, Laurie and Hill, List of land mammals of New Guinea, Celebes and adjacent islands, p. 35, June 30.

1899. _Pteropus (Spectrum) rayneri_ (part), Matschie, Die Megachiroptera ... naturkunde, p. 22; 1904, Trouessart, Catalogus Mammalium ..., Suppl., p. 51.

_Specimens examined_ (four males and one female; one embryo in alcohol).--Guadalca.n.a.l in July and November, USNM 278700-02, USNM 278142, USNM 278714.

_Measurements._--Measurements of three males and one female are, respectively, as follows: Length of head and body, --, 210, 214, 215; hind foot, --, 33, 39, 42; ear, --, 23, 23, 23; length of forearm, --, 138, 136, 134; greatest length of skull, 61.5, 59.2, 61.6, 61.2; condylobasal length, 61.4, 58.2, 60.3, 60.0; zygomatic breadth, 36.6, 35.3, 35.4, 36.5; breadth of braincase, 23.7, 22.5, 22.6, 24.1; breadth across first upper molars, --, 16.9, 16.7, 16.8; width of M1, 3.4, 3.5, 3.5, 3.5; length of maxillary tooth-row, 22.4, 22.1, 23.6, 23.2; length of mandibular tooth-row, 26.4, 25.5, 25.9, 25.6.

_Remarks._--_Pteropus rayneri_ was named on the basis of two specimens (cotypes) obtained on Guadalca.n.a.l and listed as "male" and "female"; according to Andersen (1912:254), however, both are females.

_P. r. rayneri_ is known from Guadalca.n.a.l and Malaita (see Fig. 6), and is of almost the same size as _P. r. cognatus_, which is known from San Cristobal and Ugi, only about 40 miles to the southeast. In the latter subspecies the back and rump are the same color (Prouts Brown), whereas in _P. r. rayneri_ the rump is brightly colored and therefore contrasts strongly with the dark brown back. A specimen of _rayneri_ from Malaita was reported by Sanborn (1931:15) as unusually small and having a dark-colored rump patch. In the specimens examined from Guadalca.n.a.l, there is noticeable variation in color of the mantle that does not seem related to age or s.e.x. In two specimens (adult male and female) the mantle is Cinnamon-Rufous tinged with Russet, strongly contrasting with the crown, which is Ochraceous-Tawny and has scattered silvery hairs.

Another specimen has a darker mantle (near Chestnut-Brown) and a crown of about the same color, but with a few scattered Ochraceous-Tawny hairs.

The skull of one adult male bears an extra peglike tooth posterior to M3 on the right side.

An embryo, in an advanced stage of development, in the collection of the U. S. National Museum, measures: Length of head and body, 98; hind foot, 30; ear, 8.5; length of forearm, 48 (this may be the same specimen listed by Sanborn and Nicholson, 1950:329).

=Pteropus rayneri grandis= Thomas

1887. _Pteropus grandis_ Thomas, Ann. Mag. Nat. Hist., ser. 5, 19:147, March, type from Shortland; 1887, Thomas, Proc. Zool.

Soc. London, p. 320, March 15, from Alu and Shortland; 1897, Trouessart, Catalogus Mammalium ..., 1:80, from "I. Salomonis"; 1899, Matschie, Die Megachiroptera ... naturkunde, p. 15; 1904, Trouessart, Catalogus Mammalium ..., Suppl., p. 49; 1907, Miller, Bull. U. S. Nat. Mus., 57:58, June 29; 1912, Andersen, Catalogue of the Chiroptera ... British Museum, 1:259, from Bougainville; 1931, Sanborn, Publ. Field Mus. Nat. Hist., Zool. Ser., 18:16, February 12, from Choiseul, and Santa Ysabel; 1936, Troughton, Rec. Australian Mus., 19:348, April 7; 1953, Pohle, Z.

Saugetierk., 17:128, October 27.

1954. _Pteropus rayneri grandis_, Laurie and Hill, List of land mammals of New Guinea, Celebes and adjacent islands, p. 35, June 30.

_Specimens examined_ (six males and 10 females; five in alcohol).--Choiseul in March, 23580, 23644, 23593; Bougainville in July, August, September, and October, USNM 276926-7, USNM 276968, USNM 277091-9.

_Measurements._--Average and extreme measurements of four males and seven females are as follows: Length of head and body, 281 (260-302); hind foot, 52.3 (50-58); ear, 33.1 (31-37); length of forearm, 173 (168-180). Average and extreme measurements of skulls of three males and six females are as follows: Greatest length of skull, 73.7 (71.3-77.7); condylobasal length, 73.1 (70.5-77.4); zygomatic breadth, 40 (36.4-41.5); breadth across first-upper molars, 20.9 (18.3-22.1); length of maxillary tooth-row, 28.1 (26.9-29.9); length of mandibular tooth-row, 31.8 (29.7-32.7).

_Remarks._--_Pteropus rayneri grandis_ is the largest subspecies of the species. It is also the widest ranging subspecies, being found on six islands (see Fig. 6).

Although the specimens listed above agree well with descriptions of color given by Thomas (1887_a_:147) and Andersen (1912:259, 263-264), some individual variation is noticeable. In bats not yet fully grown (judging from small size, unfused epiphyses, and lack of wear on teeth), numerous scattered hairs on the sides of the face and crown are buffy.

In adults the face and crown are blackish. With regard to individual variation in color of mantle and rump patch, specimens with the following combinations were noted (1) mantle Brick Red, rump patch bright, basal three-quarters of hairs white, tips Warm Buff (2) mantle darker, near Hessian Brown, rump patch dark, Chestnut along edges, center Ochraceous-Tawny (3) mantle Brick Red, rump patch intermediate between the two other types. Size of rump patch also is variable. In some specimens it extends onto the upper parts of the thighs whereas in other specimens it does not.

Sanborn (1931:16) reported an extra tooth, behind the last lower molar, in a specimen from Choiseul. In one of three specimens in the Bishop Museum, m3 is lacking. Judging from Troughton's (1936:346) remarks, size of individuals varies considerably. Specimens that he examined from Bougainville had longer forearms (up to 177) and larger hind feet (54-57) than those examined by me from Choiseul. On the other hand, specimens listed above from Bougainville agree well with those from Choiseul. In many specimens in the U. S. National Museum, length of the right- and left-forearm differ. For example, in No. 276926 the right forearm measures 180 whereas the left is 174; in No. 277098 the right is 172 and the left is 167. Troughton (1936:346) gave standard ear measurement in _P. r. grandis_ as ranging from 29.5 to 31.5. Ears of specimens that I examined varied from 31.0 to 37.0.

=Pteropus rayneri rubia.n.u.s= Andersen

1908. _Pteropus rubia.n.u.s_ Andersen, Ann. Mag. Nat. Hist., ser. 8, 2:366, October, type from Rubiana; 1912, Andersen, Catalogue of the Chiroptera ... British Museum, 1:255; 1931, Sanborn, Publ. Field Mus. Nat. Hist., Zool. Ser., 18:15, February 12, from Narovo (Simbo).

1954. _Pteropus rayneri rubia.n.u.s_, Laurie and Hill, List of land mammals of New Guinea, Celebes and adjacent islands, p. 35, June 30.

1888. _Pteropus grandis_ (part), Thomas, Proc. Zool. Soc. London, p. 470, December 4, from Rubiana; 1899, Matschie, Die Megachiroptera ... naturkunde, p. 15; 1904, Trouessart, Catalogus Mammalium ..., Suppl., p. 49.

_Specimens examined_ (two males and one female).--Kolombangara, in February, 23458-60.

_Measurements._--Measurements of two males and one female are, respectively, as follows: Length of head and body, 253, 265, 251; hind foot, 53, 50, 50; ear, 30, 31, 32; length of forearm, 158, 161, 160; greatest length of skull, 70.2, 67.4, --; condylobasal length, 67.0, --, 68.4; zygomatic breadth, 40.0, 39.4, 40.7; breadth across first upper molars, 19.4, 20.4, 19.9; length of mandible, 53.9, 49.4, 51.3.

_Remarks._--Kolombangara Island is a new locality for _Pteropus rayneri rubia.n.u.s_; heretofore this subspecies was known only from Rubiana and Narovo islands (Andersen, 1908:366; Sanborn, 1931:15). The coloration of a specimen from Narovo Island was described as between that of _P. r.

rubia.n.u.s_ and _P. r. lavella.n.u.s_. Sanborn (1931:16) allocated it to the subspecies _rubia.n.u.s_ on the basis of length of forearm.

Andersen's descriptions (1908:366; 1912:256) of _rubia.n.u.s_ were of a specimen stored in alcohol. Coloration of the museum skins examined by me is as follows: Dorsum from shoulders to rump near Vand.y.k.e Brown; crown and mantle Brick Red; face close to Mummy Brown; rump patch and thighs close to Warm Buff, strongly contrasting with back and mantle; base of hairs dark, Seal Brown; venter dark; chest about same as back but paler laterally (to Ochraceous Tawny); throat Brick Red.

=Pteropus rayneri lavella.n.u.s= Andersen

1908. _Pteropus lavella.n.u.s_ Andersen, Ann. Mag. Nat. Hist., ser. 8, 2:366, October, type from Vella Lavella; 1912, Andersen, Catalogue of the Chiroptera ... British Museum, 1:259; 1931, Sanborn, Publ. Field Mus. Nat. Hist., Zool. Ser., 18:16, February 12, from Ghizo and Ronongo.

1954. _Pteropus rayneri lavella.n.u.s_, Laurie and Hill, List of land mammals of New Guinea, Celebes and adjacent islands, p. 36, June 30.

_Specimens examined_ (one male and one female).--Vella Lavella in November, 23192, 23142.

_Measurements._--Measurements of a male and a female are, respectively, as follows: Length of head and body, 286, 282; hind foot, 55, 56; ear, 30, 30; length of forearm, 156, 155; greatest length of skull, 72.9, 67.6; condylobasal length, 71.8, 64.2; zygomatic breadth, 38.4, 37.9; breadth across first upper molars, 19.9, 19.8; length of mandible, 54.6, 50.8.

_Remarks._--_Pteropus rayneri lavella.n.u.s_ inhabits islands geographically near those from which _P. r. rubia.n.u.s_ is known (see Fig.

6) and in most respects the two subspecies closely resemble each other.

_P. r. lavella.n.u.s_ is slightly the smaller (average length of forearm about 156 instead of 160) and darker. A bat from Narovo [Simbo] Island, only a few miles from Vella Lavella, identified by Sanborn (1931:16) on basis of its size as _P. r. rubia.n.u.s_, resembled the subspecies _lavella.n.u.s_ in color and probably represents an intergrade between the two populations.