Hoplopleura alstoni, Musser, Guy G., Durden, Lance A., Holden, Mary Ellen & Light, Jessica E., 2010

Musser, Guy G., Durden, Lance A., Holden, Mary Ellen & Light, Jessica E., 2010, Systematic Review of Endemic Sulawesi Squirrels (Rodentia, Sciuridae), with Descriptions of New Species of Associated Sucking Lice (Insecta, Anoplura), and Phylogenetic and Zoogeographic Assessments of Sciurid Lice, Bulletin of the American Museum of Natural History 2010 (339), pp. 1-260 : 1-260

Hoplopleura alstoni , new species

HOLOTYPE AND TYPE LOCALITY: Female ex female Prosciurillus alstoni (USNM 219519; Rodentia , Sciuridae , Nannosciurinae, Nannosciurini, Hyosciurina) collected by H.C. Raven at 31 m at Pinedapa (01 ° 259S, 120 ° 359E; see gazetteer and fig. 11), Propensi Sulawesi Tengah, Indonesia on 15 February, 1918. The holotype is deposited in the USNM.

REFERRED SPECIMENS: The holotype is the only example of the species.

DISTRIBUTION: Hoplopleura alstoni is known only from Prosciurillus alstoni , which is recorded from a voucher host collected at 31 m. The tree squirrel is found at lowland elevations in the northeastern portion of the central core of Sulawesi, its east-central arm, and the southeastern peninsula and offshore islands (see fig. 11 and table 4).

ETYMOLOGY: Named for the specific epithet of the host species.

DIAGNOSIS: The female of Hoplopleura alstoni can be distinguished from females of all other species of Hoplopleura using a combination of the following characters: (1) the shape and length of the apical paratergal setae; (2) the almost flat anterior apex of the head; (3) the distinctive shape, proportions, and setation of the genitalia (fig. 49D), especially the shape of the subgenital plate and the positions and lengths of its associated setae. Females of all eight of the species of Hoplopleura described from Sulawesi squirrels in this report are easily distinguished from each other (and from all other species of Hoplopleura ) by the distinctive shapes of their subgenital plates and the characteristics (positions and lengths) of the setae attached to these plates.

DESCRIPTION: Female (fig. 49A–D). Length of holotype 1.43 mm. Head, thorax, and abdomen well sclerotized.

Head. Longer than wide with blunt, almost flat, anterior apex; 2 SuHS, 3 DMHS, 1 DAnCHS, 3 AnMHS, and 1 VPHS on each side; DPHS fairly long, extending to mesothoracic spiracle, with 1 DAcHS medial to DPHS. Antennae. 5-segmented with basal segment much wider than second segment, wider than long; second segment elongate.

Thorax. Slightly broader than long; thoracic sternal plate (fig. 49B) with broadly rounded anterior apex, tapering, fairly broadly rounded posterior apex and broadly rounded lateral margins; mesothoracic spiracle moderate in size (0.021 mm in diameter); DPTS fairly long (0.16 mm), extending to mid-region of paratergal plate II; no DMsS evident. Legs. Fore and mid coxae subtriangular; forelegs small each with narrow acuminate claw; hindlegs robust each with broad acuminate claw; midlegs intermediate in size between fore and hind legs.

Abdomen. Wider than thorax; 15 plates dorsally with three narrow plates on each of segments 4–7, two narrow plates on segment 8, and one broad plate on segment 9; 16 plates ventrally anterior to subgenital plate with one small plate on segment 1, one broad plate on each of segments 2 and 3, three narrow plates on each of segments 4–7, and one narrow plate on segment 8; first and second rows of DCAS each with two long narrow setae, third row with four long narrow DCAS, followed by 14 rows of TeAS each with 6–9 dagger-shaped setae and then by one row of six narrow TeAS; 11 rows of 1–2 DLAS on each on each side extending from segments 4–8; first ventral plate without setae; ventral plates 2–16 each with 6–10 StAS; ventral plate 2 with six long, narrow StAS; ventral plate 3 with two robust StAS on each side and three narrow medial StAS; ventral plates 4–16 each with dagger-shaped StAS; plates 2 and 3 each articulating with corresponding paratergal plates. Paratergal plates (fig. 49C) present on segments 1–8: plate II with one apical seta of intermediate length but with other apical seta broken at base (on both sides); plates III–VI each with two apical setae of intermediate length but with one seta slightly longer than other seta on each plate; plates VII and VIII each with two long apical setae; all plates subtriangular; plates II–VI each with both apical angles produced into points; plates III–VII each with moderate size spiracle.

Genitalia (fig. 49D). Subgenital plate separated into two laterally elongate, broad sections with anterior plate distinctly larger than posterior plate; anterior section of subgenital plate curved with posterior, medial, broadly rounded apex bearing eight setae consisting of two setae of intermediate length on each side and four small medial setae; two long lateral setae also present on each side of anterior section of subgenital plate; posterior section of subgenital plate subeliptical and with two fairly small lateral setae on each side; gonopods VIII each with three apical setae increasing in length from anterior to posterior; gonopods IX each with one stout seta; vulvar fimbriae indistinct.

REMARKS: Because only the holotype female was available for this new species, many of the remarks made above for Hoplopleura leucomus , for which only three females were available, could be repeated here. We decided to describe H. alstoni based only on the holotype female because the subgenital plate and its associated setae are highly distinctive and because this louse evidently cospeciated with its host. The result of this apparent cospeciation is that each of the eight Sulawesi squirrel species from which we obtained lice has a unique species of louse. Obviously, the male of Hoplopleura alstoni should be described if additional material becomes available.