Afraustraloxenodes hulleyi, Duy-Jacquemin, 2003

Duy-Jacquemin, Monique Nguyen, 2003, A new genus of Penicillata from Southern Africa with pseudoarticulated sensilla on the palpi of the gnathochilarium (Diplopoda: Polyxenida: Polyxenidae), African Invertebrates 44 (1), pp. 71-88 : 81-83

Afraustraloxenodes hulleyi sp. n.

( Figs 41–54 )

Etymology: This species is named for its collector, P. Hulley. This name was proposed by B. Condé in his correspondence with Lawrence (1966).

Type material: Holotype adult male and paratype adult female ( MNHN), SOUTH AFRICA: Cape Province, Port Alfred, ix.1958, P. Hulley, no. 7231. Other paratypes: one adult male, one female with 12 pairs of legs, one individual with 6 pairs of legs ( MNHN), SOUTH AFRICA: Cape Province, Kowie River Mouth, Port Alfred , near Grahamstown, 5.v.1958, P. Hulley, R. F. Lawrence.

Description of adults:

Measurements: Body length (without caudal penicil): 1.85 mm (holotype) to 2.60 mm; length of caudal penicil: 0.40 mm. Tarsus II of 13th leg: 88 (holotype) to 96 m long.

Head: Eight ocelli on each side. Vertex with one pair of posterior tufts ( Fig. 41 ) consisting of two rows: anterior row with seven to 12; posterior row with seven to 11 trichomes, posteriormost trichome slightly behind trichobothria. Distance between each tuft small. Proportions of antennal articles as in Fig. 44 ; ratio length/diameter of article VI = 1.45 to 1.60. Antennal article VI with four dorsal sensilla basiconica: anterior two short and slightly more apical than longer posterior two ( Figs 42, 46, 54 ); one sensillum coeloconicum between two posterior sensilla basiconica; one setiform sensillum between two short anterior sensilla. Antennal article VII with two dorsal sensilla basiconica: posterior one shorter than anterior; one posterior sensillum coeloconicum and one setiform sensillum between two sensilla basiconica ( Figs 45, 53 ). Three trichobothria of equal size, each with a cylindrical funiculum. Entire surface of labrum with numerous small, cuspidate papillae (also called cuticular setae) in addition to four to five anterior rows of spherical papillae ( Fig. 47 ). 5+5 lamellate teeth at anterior margin. Clypeo-labrum with nine to 12 setae along posterior margin. In female, outer palp of gnathochilarium with 10 pseudoarticulated sensilla apically; middle palp with 21 sensilla, comprising 14 long pseudoarticulated sensilla and seven short nonarticulated sensilla.

Trunk: Except on tergites VIII or IX to X, trichomes arranged in three rows and two lateral tufts. Each lateral tuft connected with three rows of trichomes: posterior row running along posterior margin of tergite; two more anterior rows with a few trichomes spaced apart. Total number of trichomes of each tuft on tergites as follows: tergite I 29 to 38; tergites II to VII 45 to 87. Lateral protuberance of tergite I with three or four trichomes ( Fig. 41 ).

Legs: Coxa, trochanter and prefemur each bearing a seta with oval base furnished with acute process apically. Chaetotaxy as follows: coxa I with one seta, II to XII generally with two setae ( Fig. 50 ); trochanter with one seta; only some femora with a small seta each; prefemur with one large seta ( Fig. 49 ) and one or two small aligned setae. Second tarsus with a small seta. Pretarsus similar to that of namibiensis and coineaui ; anterior process of pretarsus with a spinous projection slightly shorter than claw, two subequal latero-anterior and posterior spiniform processes, and a posterior lamellate process ( Figs 51, 52 ).

Male: All areas of penis with cuticular setae. Coxal glands on legs VII, VIII and IX.

Telson : Four setae above anal valve, two external ones with raised base. Bundle of caudal penicil unseparated. On each side, dorsal trichomes consisting of two or three trichomes (a) (three in holotype), one trichome (b), seven to 10 trichomes (c) (eight in holotype). Trichomes of caudal penicil generally with three ( Fig. 48 ), sometimes four ( Fig. 43 ), hooks.

Female with 12 pairs of legs (subadult):

Measurements: Body length (without caudal penicil): 2 mm. Length of tarsus II of 12th leg: 88 m.

Posterior tufts of vertex with anterior row of eight and nine trichomes, posterior row of eight and seven trichomes, variation depending on body side. External structure of labrum as in adults with three to four anterior rows of spherical papillae. 6+5 lamellate teeth at anterior margin. Clypeo-labrum with 10 setae along posterior margin. Outer palp of gnathochilarium with 10 sensilla.Antennal characters identical to those of adults. Ventral caudal transitory tufts (present in larvae only) with about 20 trichomes.

Larva with six pairs of legs:

Measurements: Body length (without caudal penicil): 1.50 mm. Length of tarsus II of 6th leg: 80 m.

Head: Posterior tufts with anterior row of eight and nine trichomes, posterior row of five and six trichomes. Antennal sensilla identical to those of adults.

Telson : Two and three trichomes (a). Transitory tufts with a dozen trichomes.

Remarks: Three pairs of coxal glands are rarely observed in Polyxenidae . Usually they only show two pairs.

Figures

Figs 41–54. Afraustraloxenodes hulleyi sp. n. 41–43. Paratype, adult male; 41. Head and collum, dorsal view. 42. Sensilla of articles VI of left antenna. 43. Distal part of crooked trichomes. 44–52. Holotype female. 44. Right antenna. 45–46. Sensilla of articles VII and VI of the same antenna. 47. Labrum, only part of cuticular setae shown. 48. Distal part of crooked trichome. 49. Seta on prefemur of right leg I. 50. Seta on coxa of left leg III. 51–52. Right telotarsi IV and VI, anterior view. 53–54.Adult male from Kowie River mouth, sensilla of articles VII and VI of left antenna. Scale bars: Figs 41, 43, 44 = 50 m; other figures = 25 m.