Heptapactes, QUADRISAETOSUS, 2007

Schmidt, Christian, 2007, Revision of the Neotropical Scleropactidae (Crustacea: Oniscidea), Zoological Journal of the Linnean Society 151, pp. 1-339 : 19

publication ID	https://doi.org/ 10.1111/j.1096-3642.2007.00286.x
persistent identifier	https://treatment.plazi.org/id/03858799-422E-FFF8-9B8A-7ABDAD27F9F8
treatment provided by	Felipe
scientific name	Heptapactes
status	gen. nov.

Treatment

HEPTAPACTES QUADRISAETOSUS View in CoL

GEN. NOV., SP. NOV.

Material examined

Type specimens: One ♂, holotype ( Brazil, Amazonas, Manaus, leg. H. Schubart, 17 April 1966, MNRJ 3321 View Materials ); one ♀ m, paratype (same data, MNRJ 18645 View Materials ) (Map Fig. 24 View Figure 24 ) .

Description ( Figs 18–23 View Figure 18 View Figure 19 View Figure 20 View Figure 21 View Figure 22 View Figure 23 )

Male 0.9 mm wide, cephalothorax 0.51 mm wide. Female with marsupium, cephalothorax 0.65 mm wide. Both specimens with 7/7 ommatidia. No linea supraantennalis. Cephalothorax is behind the upper margin of the frontal shield with a transverse furrow, which laterally terminates near the eyes.

According to the preserved traces of pigment, the specimens may have been uniformly brown with pale muscle insertions. Details of the surface could not be seen, due to the poor preservation of the specimens; noduli laterales could not be found with certainty, but, if present, they are small (otherwise it would have been possible to see at least their insertions).

First antenna three-jointed, with two large apical aesthetascs and two smaller subapical aesthetascs on the distal article. Second antenna about as long as pereiopod 7, but much thicker. Flagellum two-jointed, with one (?) aesthestasc on the distal article. Apical cone as long as the flagellum, slender, and with one lateral free sensillum. Fifth article of second antenna bears a subapical seta, which is as long as the flagellum.

Left mandible: pars incisiva large, with five cusps, lacinia mobilis with two cusps, lobe proximal of the lacinia bearing few scales and two hairy setae, one hairy seta between this lobe and the pars molaris, which is represented by a tuft of (few) hairy setae. Right mandible: pars incisiva, lacinia mobilis and lobe smaller, the latter with only one hairy seta. Otherwise as left mandible. Both mandibles with one (?) scale setae (and some scales?) on the outer surface. First maxilla lateral endite with lateral group of five large simple tooth setae and one slender seta, and mesal group of six more slender setae, four of them apically cleft. One very small seta in subapical position beside the mesal group of tooth setae, on the caudal face. Distal third of lateral endite fringed with hairs (pectinate scales). Mesal endite bearing four penicils, the lateralmost slightly smaller than the other three. Second maxilla apically bilobate, mesal lobe with some coarsely scattered sensilla on the margin. One (?) sensillum between the lobes. Lateral lobe appears hairy (pectinate scales). Maxilliped palp three-jointed, proximal article with only one seta near the median margin; second article on the mesal margin with distal tuft of setae on a long socket, and proximal ‘tuft’ represented only by a single seta on a short socket; lateral margin of second article with one stout and one slen- der seta. Apical article with an apical tuft of setae and three (?) single setae on the lateral margin. Maxilliped endite with some pectinate scales, one simple seta near the inner corner on the caudal face, and a very large and stout penicil on the frontal face. Maxilliped basis with scales and scale setae on the caudal face and fine hairs on the laterodistal edge.

Pereiopods with relatively large scales, as is usual in small Oniscidea. Pereiopod 1 on frontal face of carpus with large brush composed of scales; on the propodus there is a smaller field of spine-shaped scales (or setae?). Other pereiopods without anything special (e.g. without ventral brushes and without any protrusions). Dactyli with slender inner claw nearly as long as outer claw, ungual seta distally somewhat enlarged, dactylar seta distally with a fringe of setules on one side, and a number of other scales and setae (the exact number could not be determined because of the poor condition of the specimen). Whether there is a small seta beside the ungual seta could not be determined.

All pleopod exopodites without conspicuous respiratory fields. Male pleopods: pleopod 1 exopodite without marginal setae, exopodites 2–5 with one (two) marginal seta and some pectinate scales near the mesal margin. Pleopod 1 exopodite wider than long. Pleopod 5 exopodite with a groove along the median margin, and with pectinate scales on the caudal face. Owing to the poor state of preservation of the specimen, it remains unclear whether the irregular arrangement of these pectinate scales is natural or an artefact. Pleopod 1 endopodite with straight distal portion directed laterally at an angle of about 35°. The distal portion shows no row of small spine-like setae; this may be a preservation artefact. Pleopod 2 endopodite broken on both sides, so that its length remains unknown. However, the preserved part is already about one and a half times as long as the exopodite.

Remark

The two available specimens are poorly preserved, but they clearly represent a previously undescribed species. They have well-developed eyes, and their transverse groove on the cephalothorax is not projected laterally as far as in the other members of the Scleropactidae with eyes.