Crossodonthina hainana Xiong et al., 2005

Luo, Yongzheng & Chen, Jian-Xiu, 2010, Redescription of two Crossodonthina species (Collembola: Neanuridae: Lobellini) from China, Journal of Natural History 44 (35 - 36), pp. 2119-2129 : 2120-2124

publication ID	https://doi.org/ 10.1080/00222933.2010.488751
persistent identifier	https://treatment.plazi.org/id/03F687A1-FFC0-A509-8BFE-7E3E9DE3FBDA
treatment provided by	Felipe
scientific name	Crossodonthina hainana Xiong et al., 2005
status

Treatment

Crossodonthina hainana Xiong et al., 2005 View in CoL

( Figure 1 View Figure 1 , Table 1)

Type locality

China: Hainan Province, Dongzhaigang Mangrove Natural Reserve.

Material examined

Holotype (female) and 12 paratypes (6 females, 6 males), Dongzhaigang Mangrove Natural Reserve (19°55′N, 110°34′E), Hainan Province, China, deposited in SIPPE; 3 other specimens (females) on slides, collected at same locality as types, 26 March 2009 and 10 June 2009, collection number C9586 and C9587, collected by Mr. Zhang Yiyun, deposited in NJU. GoogleMaps

Redescription

Body length. Up to 2.2 mm.

Colour. Red while living, white in alcohol.

Head. Eyes 2+2, unpigmented and separated from each other ( Figure 1A View Figure 1 ). Length ratio of antenna to head as 1:1.2−1.3. Ant. III and IV dorsally fused. Length ratio of antennal segments as I:II:(III + IV) = 1:1.0:2.0. Ant. I and II respectively with 9 and 11 setae. Ant. III with 18 setae and Ant. III organ, 5 sensory setae, including sgd, sgv, ms and 2 strongly curved rods in separate pits. Ant. IV apical bulb trilobed, dorsal chaetotaxy as 8S, i, 12 mou and or ( Figure 1B View Figure 1 ). Buccal cone weakly developed. Labrum truncate and granulated, setal formula as 2/6, 2, sometimes two or four microsetae present in front to prelabral setae ( Figure 1C View Figure 1 ). Labium with 2 x and three setae (A, C, D) on proximal part of palp, four (E, F, G, F) on submentum and four (b, c, d, e) on mentum ( Massoud 1967) ( Figure 1D View Figure 1 ). Mandible elongate, consisting of two fringed rami with simple setae, three smooth flagella and five basal teeth. Lower ramus two times length of upper one and with two rows of setae. Flagella situated between rami, subequal to lower ramus in length. Three teeth situated on upper basal lamella, other two on lower lamella ( Figure 1F View Figure 1 ). Maxillary head consisting of two rami, inner one with two unequal apical teeth; outer one bifurcated twice into three lamellae, outer lamella with small thorn-like tooth ( Figure 1E View Figure 1 ).

Cephalic tubercles and chaetotaxy. Dorsal central area with 6 tubercles and 19 setae, seta Ocp absent. Posterior area with 4 tubercles and 8 setae; tubercle Di with seta Di1, De with seta Di2, De1, De2. Lateral area with 3 tubercles (Dl, L, So) fused and 16 setae ( Figure 1A View Figure 1 , Table 1). Ventral side respectively with 6 and 9(8) setae in areas Vi and Ve.

Body tubercles and chaetotaxy. Macrosetae weakly ciliated, without marginal wings, apically knobbed, some on lateral tubercles acuminate ( Figure 1G View Figure 1 ). Th. I with 3+3 tubercles (Di, De, Dl). Th. II− Abd. IV respectively with 4+4 tubercles (Di, De, Dl, L). Abd. V dorsally with 2+2 tubercles (Di separated, De and Dl fused); tubercle L separated and ventrally situated. Abd. VI with 1+1 tubercles ( Figure 1A View Figure 1 and Table 1). S and ms on half terga of Th. II− Abd. V formula as 2+ms, 2/1,1,1,1,1. Each anal valve (Av) with 3(2) microsetae in both sexes. Genital plate with 14−27 and 31−46 setae respectively in female and male ( Figure 1H View Figure 1 ).

Appendices. Chaetotaxy of legs, ventral tube and furcal remnant shown in Table 1. Tibiotarsi I and II respectively with 19 setae (T1−T4, A1−A7, B1−B7 and M). Tibiotarsus III with 18 setae, B7 absent; B5 shorter than inner edge of unguis. Unguis ventrally with 1 inner tooth, basal granules and medial transverse striae. Unguiculus and tenent hair absent ( Figure 1I View Figure 1 ). Ventral tube anteriorly with 1+1 proximal and 3 + 3 distal setae. Furca reduced to elliptic area with 6 setae ( Figure 1H View Figure 1 ).

Biotope

Found in litter of seaside wharf.

Remarks

In the present paper, Chinese species C. hainana from Hainan is detailedly redescribed on the basis of reexamining 13 types and 3 other specimens from the type locality. Corrections are made to the original description and figures as the following ( Table 1): mandible consists of two fringed rami, three smooth flagella and five basal teeth rather than only two feathered rami and three basal teeth in the original description; maxillary outer ramus is bifurcated twice into three lamellae instead of bifurcated once into two lamellae; and macrosetae are weakly ciliated with knobbed apex rather than smooth with rounded apex. Also, some additional characters are described and illustrated, such as the labrum, labium, complete chaetotaxy of antenna, hind leg and ventral chaetotaxy of Abd. I – VI .

The labral chaetotaxy of this species is /6, 2 with two or four microsetae sometimes present in front to prelabral setae, instead of /2, 2 as in most species of Lobellini. So far, species with 2+2 eyes in the genus are only found in China. C. hainana is similar to the 2+2-eyed species, C. montana Lee and Kim, 1990 from Taiwan and C. bidentata Luo and Chen, 2009 from Zhejiang, in antenna, unguis, ventral tube and body dorsal chaetotaxy. However, it is easily distinguished from the latter two by some characters unique in the genus, such as furcal remnant with six setae, labral chaetotaxy as 2/6, 2, and the structure of mandible, maxilla, and macroseta.