Tomocerus qinae Yu & Yao & Hu 2016, sp. nov.
Creators: name: Yu, Daoyuan
name: Yao, Jin
name: Hu, Feng
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Collembola
Entomobryomorpha
Tomoceridae
Tomocerus
Tomocerus qinae

description: Tomocerus qinae Yu sp. nov.
Figs 1A–D, 2, 3
Type material. Holotype female on slide. Collected in Purple Mountain, Nanjing, Jiangsu Province, China, 118°53'6.7"E, 32°3'40.4''N, alt. 117m, 15.iii.2015, by Chunyan Qin & Daoyuan Yu (sample code NJ2015ZJ-1). Paratypes six females on slides, nine in alcohol, same data as holotype. Deposited in NJAU.
Description. Body length 3.1–4.5 mm. Ground colour of head and terga yellow, with unpigmented patches all over; ventral side of body white. Ant. III and IV bluish gray; Ant. I and Ant. II with diffuse pigment, dorsal side darker. Eye patches black, dark blue pigment extended anteriorly towards dorso-lateral side of antennal base and posteriorly along lateral side of head. Lateral side of Th. II, Th. III and Abd. I with broad dark band. Legs with diffuse gray pigment, distal part of femurs and tibiotarsi darker than proximal parts (Fig. 1A). Manubrium dorsally with two longitudinal bands of spotted blue pigment along chaetal stripes; dens with brown pigment at middle and fading gradually towards apex (Fig. 1B). Scales brown.
PAO not seen. Eyes 6+6. Antenna 1.2–1.3 times as long as body. Antenna length ratio as I:II:III:IV= 1.0:1.4– 1.5:15.2–15.5:1.2–1.4. Both dorsal and ventral sides of Ant. I and Ant. II scaled, base of Ant. III dorsally scaled, Ant. IV unscaled. Labral formula 4/5, 5, 4, distal four chaetae stronger. Distal edge of labrum with four curved papillae. Mandibular heads asymmetrical, left one with four teeth and right one with five, left molar plate distally with tapered tooth (Fig. 2A). Basal teeth of maxillary lamella 5 prolonged, without beard-like appendage (Fig. 2B). Maxillary outer lobe with trifurcate palp, basal chaeta and four sublobal hairs (Fig. 2C). Both dorsal and ventral sides of head scaled. Cephalic dorsal macrochaetotaxy: anterior area: 2, 4; interocular area: 2, 7, with central chaeta; postocular area: 2+2; posterior area: 2+2. Posterior margin with about 40+40 small chaetae (Fig. 2D). Mentum with 5 chaetae, submentum with numerous chaetae.
Pattern of body chaetotaxy as Fig. 2E. Bothriotricha formula as 2, 1/ 0, 0, 1, 2, 0, 0. Th. II with dense macrochaetae along anterior margin (not shown in figure) and row of macrochaetae behind anterior margin. Number of macrochaetae or large mesochaetae in posterior row as 3, 3/ 3, 3, 4, 2, 4 (3 dorsal+1 lateral). On Th. II five central macrochaeta arranged in triangle pattern, usually with a smaller macrochaeta lateral to them; on Th. III antero-lateral macrochaeta present; Abd. III with two anterior macrochaetae; Abd. IV with antero-lateral macrochaeta; on Abd. V inner posterior macrochaeta smaller than others; Abd. VI with numerous chaetae of moderate size. Most mesochaetae laterally and posteriorly on terga. Pseudopores near the middle line of terga, formula as 1, 1/ 1, 1, 1, 1, 0, 0; on Th. II pseudopore near posterior macrochaeta of central triangle.
Trochantero-femoral organ with 1, 1 slender chaetae (Fig. 2F). Front, middle and hind tibiotarsus ventrally with 5–6, 6–8, 7–8 strong spine-like chaetae, proximal one or two strong chaetae gradually narrowed towards apices and pointed, others subcylindrical, suddenly narrowed near apices, blunt or pointed (Fig. 2G). Each tibiotarsus with a distal whorl of 11 chaetae, ventral six as ordinary chaetae, dorsal five modified: tenent hair strong and clavate, as long as or slightly longer than inner edge of unguis; two accessory chaetae minute, smaller than pretarsal chaetae; two guard chaetae thin and long. Unguis slender, with baso-internal ridging visible in lateral view; lateral teeth pointed, of moderate size. Inner edge of unguis with 4–6 teeth, basal tooth of moderate size, subbasal tooth strongest, distal ones much smaller. Unguiculus 0.5–0.6 times as long as unguis, inner edge with 0–1 small tooth. Pretarsus chaetae 1+1 (Fig. 2H).
Ventral tube with scales on both anterior and posterior faces, anterior face with 40–60 chaetae on each side, posterior face with about 70 chaetae, lateral flaps unscaled, each lateral flap with about 100 chaetae. Rami of tenaculum with 4+4 teeth, anterior face of corpus with 13–17 chaetae and 2–4 scales (Fig. 3A). Ratio manubrium:dens:mucro=4.6–4.8: 5.4–5.9: 1.0. Manubrium ventrally scaled, without chaetae, laterally with large round scales and 11 chaetae, proximal chaeta small and slender, distal 10 chaetae distinctly stronger; each dorsal chaetal stripe with about 200 chaetae of different sizes, without blunt prominent chaetae; file of dorsal scales along inner side of chaetal stripe, running about half length of manubrium from base; pseudopores 18–23 on each side (Fig. 3B); external corner chaeta as large as moderate sized mesochaetae in chaetal stripe (Fig. 3C). Dens basally without inner large modified scale or outer strong chaetae. Dental spines formula as 4–5/4–5, II, distal spine strongest (Fig. 3D); all spines with numerous denticles of moderate size (Fig. 1C, D). Dens dorsally with ordinary chaetae and feather-like chaetae as in other Tomocerinae, ventrally covered by scales. Mucro elongated, with numerous smooth chaetae with elongated sockets; both basal teeth with proximal lamellae, outer tooth with toothlet; apical and subapical tooth subequal; two dorsal lamellae running from subapical tooth, outer lamella ending in inner basal tooth, inner lamella ending freely at base; outer lamella with 5–9 intermediate teeth (Fig. 3E).
Etymology. Named after the collector Miss Chunyan Qin.
Ecology. In semi-decomposed woods.
Genebank accession number: KT246490, KT246491, KT246492.
Remarks. Tomocerus qinae sp. nov. is so similar to T. ocreatus in the shape and arrangement of dental spines, that it was previously misidentified as the known species, but it can be distinguished from the latter by the following characters. According to the original description by Denis (1948), T. ocreatus has rather pale body colour, the dark blue or gray pigment is present only on antennae and tibiotarsi; the antennae are as long as the body; the sub-basal tooth on unguis is as large as the distal ones. In contrast, Tomocerus qinae sp. nov. has a remarkable colour pattern similar to that of Pogonognathellus elongatus Maynard, 1951; the antennae are distinctly longer than the body; the sub-basal ungual tooth is clearly larger than the distal ones. An ambiguous difference is the dental spines formula. In specimens of the same size (about 3.3 mm), Tomocerus qinae sp. nov. has more spines than T. ocreatus (4–5/4–5, II versus 3/3–4, II), but since the description of T. ocreatus was based on only one specimen, this character is not fully reliable for distinguishing the two species.
Some characters may change during postembryonic development. In small sized adult specimens the body colour may be paler, but the pattern always exists. In subadults the sub-basal ungual tooth is not as prominent as in fully developed individuals, but is still stronger than the other teeth. Juveniles have smaller number of ungual teeth, dental spines and mucronal intermediate teeth. The first instar is light purple all over and without pattern. The variations also exist among adults. In several individuals the smaller macrochaeta beside the central "triangle" on Th. II is absent from one side, in two specimens a postero-lateral microchaeta on Th. II is modified as a mesochaeta on one side, thus the whole chaetotaxy on Th. II may be asymmetrical (Fig. 2E). In one specimen an additional macrochaeta appears laterally in the interocular area on head; another specimen has multiple additional dental spines, including a small spine between two distal large ones (Fig. 3F), which is similar to Tomocerus folsomi Denis, 1929. The last two variations are considered as malformation because they are observed in single case only.
description: Published as part of Yu, Daoyuan, Yao, Jin & Hu, Feng, 2016, Two new species of Tomocerus ocreatus complex (Collembola, Tomoceridae) from Nanjing, China, pp. 125-134 in Zootaxa 4084 (1) on pages 126-130, DOI: 10.11646/zootaxa.4084.1.6, http://zenodo.org/record/1050917