Revision of the Neotropical Scleropactidae (Crustacea: Oniscidea) Author Schmidt, Christian text Zoological Journal of the Linnean Society 2007 2007-11-30 151 1 339 https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/j.1096-3642.2007.00286.x journal article 10.1111/j.1096-3642.2007.00286.x 0024-4082 5430080 CIRCONISCUS HIRSUTUS SP. NOV. Material examined Holotype ♂ , one ♀ m and two ♀ without marsupium ( Brazil , near Manaus , Lago Janauri , leg. Irmler , 17 May to 7 June 1972 , SMNS 10064 b) ( pitfall trap with formalin, mixed water inundation forest, narrow strip between Rio Negro and Rio Solimões , opposite of Manaus ). Description ( Figs 197–202 ) Holotype male 5.0 × 2.4 mm (cephalothorax 1.37 mm wide), paratype female 5.8 × 2.75 mm (cephalothorax 1.55 mm wide) to 3.1 mm wide (cephalothorax 1.75 mm wide). Dark brown, with cephalothorax, coxal plates, pleon-epimera, uropods, muscle insertions and some patches on tergites pale (as the specimens had been stored in alcohol for 28 years, the original coloration is not exactly known). First coxal plate pale at posterior corner. A pale patch on anterior corner of first coxal plate might be an artefact. Coxal plate 1 with a schisma as typical for the genus, the following coxal plates simple. Tegites appear hirsute due to the raised scale setae and large, band-shaped scales. In the median portion of hind margin of tergites a row of scale setae that are broader than on the main surface. Pereion-tergites with one pair of noduli laterales each, all at the same distance from lateral margin and near posterior margin. Noduli differ from tergal scale setae mainly in that the sensory seta is more protruding. Pleotelson roughly triangular, with broadly rounded tip and weakly concave sides, exceeded by uropod sympodites, which are rounded and seem to bear some gland pores. Eyes composed of 15–17 ommatidia. First antenna three-jointed, third article about as long as first article and bearing six aesthetascs in three transverse rows. (Whether the scale-like object beside the distal aesthetascs shown on the drawing belongs there or is an artefact will be shown by examination of more specimens.) Second antenna shorter than pereiopod 1 and rather stout. Flagellum stout, conical, two-jointed; distal article with aethetascs in two transverse rows and a slender apical cone. Apical cone as long as distal article of flagellum plus half of basal article. It has one small, free lateral sensillum (neither a second sensillum nor an insertion of a broken sensillum could be found; however, three of the four specimens lacked both apical cones). Mandibles: right mandible with pars incisiva forming a broad surface exceeded by four long cusps and one short cusp, small lacinia mobilis with two sharp cusps and one blunt cusp, and hairy lobe with one hairy seta. Left mandible with well-developed fourcusped pars incisiva, lacinia mobilis with two long and two short cusps, and hairy lobe bearing two hairy setae. One hairy seta between lobe and pars molaris represented by a tuft of hairy setae. Lateral face of both mandibles with some scales and few scale setae. First maxilla lateral endite on distal margin with lateral group of four long, simple setae, one simple seta of about half length, and one slender seta with one or two subapical setules, and mesal group of six more slender setae, one of which is simple, and the others of which have one or two subapical clefts. No small, subapical setae could be seen. Distal 0.4 of lateral margin of lateral endite fringed with hairs (pectinate scales). Mesal endite of first maxilla bears two penicils and a rounded distolateral corner. Second maxilla apically bilobate, lateral lobe being broader than mesal lobe and bearing an irregular row of sensilla on the distal margin. Three single sensilla between the lobes. Maxilliped base on whole surface except for laterodistal corner with rather irregular, large and protruding scales, and some scale setae. Endite rectangular, hairy, with one seta on the lateral corner, one small seta on the caudal face in a subapical position, and one penicil near the mesal corner on the frontal surface; one small, conical seta in a more basal position on the frontal face. Maxilliped palp basal article bearing a single large setae near the mesal margin. (The distal portions of the palp were damaged or lost.) Pereiopods with large scales, which are irregular and protruding on articles except for basipodite; on the latter, scales more regularly arranged, and in pereipods 2–6 several rows of raised scales form a structure like water-conducting scale rows (pereiopod 7 lost). Pereiopod 1 with a brush of fringed scales on carpus and spine-like scales or setae and few fringed scales on propodus. Several scales with fringed apical margin also present on carpus of pereiopod 2, and one such scale on the carpus of pereiopod 3. Some scales on ventral face of male pereiopod 1 merus and pereiopod 2 merus and carpus. Dactyli with inner claw about one-third as long as outer claw. Ungual seta as long as outer claw or somewhat shorter, beside its base with a more slender seta exceeding half its length. Dactylar seta with two fringes of setules on distal portion. One smaller, simple seta in a subapical position on both the frontal and caudal faces. No distinct aesthetasc-like setae beside the dactylar seta have been seen (some irregular inflations on setae and dactyli of the pereiopods are thought to be caused by a fungal infection). One object probably representing a reproductive part of a fungus is seen on distalmost seta of pereiopod 1 carpus (pereiopod 7 was lost). Genital papilla with strong lanceolate ventral shield exceeding by a cordiform lobe bearing the genital orifices on its corners. Pleopods: male pleopod 1 exopodite lost, others partly damaged. Male pleopod 1 endopodite very broad, only subapically slightly constricted, with a row of small setae that has a short recurrent part before changing from the caudal face to the frontal face approximately at the transverse distal margin. Pleopod 2–4 (and 5?) exopodites with one simple marginal seta. Male pleopod 2 exopodite long, somewhat exceeded by the (incompletely preserved) endopodite. Male pleopod 5 exopodite on dorsal face with irregular field of pectinate scales of different size and a distinct and deep furrow along the medial margin. Uropod exopodite about half as long as endopodite but 1.5 times as broad. Sympodite and exopodite with some rounded structures; these could not be seen with sufficient precision to confirm which of them are gland pores and which are insertion lines of shed scales. Remarks Unfortunately, the only male lacked both pereiopod 7 and pleopod 1 exopodites, so the description remains incomplete. Mouthparts and pleopods were partly damaged, and moreover stuck together by amorphous material, which presented a strong obstacle to proper dissection. Nevertheless, the species is easily recognizable among the other species of the genus by the much more developed transverse furrow on the cephalothorax.