Katianna coeruleocephala

Redescription of Katianna coeruleocephala after Handschin, 1920 (new information in italics)

Figs 1–6

Type material. Slide label: “ Katianna coeruleocephala n. sp. Java. Naturist, Museum Basel, III, 242. Eit”.

Dimensions. Length 0.8 to 1.0 mm. Antenna longer than head (1:1.6). Antennal segments ratios: I:II:III:IV=1:2.8:4.6:9. Ant. IV clearly subsegmented with 7 segments, ratio of lengths from basal to distal segments = 5.2:1.4:1.4:1.6:1:2.4.

Size. Large abdomen distinctly globular, abdomen V and VI separate, genital/anal segments conical, similar in shape to Corynephoria.

Colour. Yellow, slightly orange/yellow. Antennae all violet, vertex (of head) and ‘cheeks’ the same but somewhat paler.

Chaetotaxy. Chaetae of antennae in whorls. Large abdomen with simple, short, backward-facing bent, upstanding chaetae, slightly longer on anal segments i.e. p osterior portion of abdomen with a field of thicker, curved, spine-like chaeta. Bothriotrix D long, fine. Genital segment at the base with 2 outstanding long bothriotricha [not seen]. Genital field prominent, densely and finely setose, with a single clavate hair pointing towards the anus [not seen].

Head and body. Antenna IV subdivided into seven subsegments. Antennal III organ not seen. Ocelli 8 + 8 on a dark black patch. No spines on the vertex of head, only fine pointed chaetae present. Segmentation of the body very slightly indicated. Two (three cannot be seen on the type) bothriotricha on large abdomen. Coxa III with 4 chaetae. Trochanter without trochanteral organ but with five external chaetae. Tibiotarsi with fairly long thick, pointed spines internally, six on leg I and ten on leg III. Tibiotarsi with three distally inflated clavate tenent hairs appressed to legs II and III, and two on leg III. Claw often with small distal inner tooth [not seen], empodial appendage lanceollate with very narrow inner and outer lamellae, broader on legs II and III, and with short, distal spine, longer on leg I. External pretarsal setulae absent but inner one present. Ventral tube sacs not seen.

Rami tenaculum with 3 distal teeth and one large basal tooth-like appendage, one short distal chaeta seen. Neosminthuroid chaeta absent. Abdominal segment VI with two, hoe-shaped bristles (spines) dorsally, one (DL1) larger than the other (DL2), m1 chaeta long and curved. Circumanal chaetae somewhat inflated, smooth. Mucro boat-shaped, with inner and outer lamellae lacking teeth, smooth. Manubrium:dens:mucro ratio= 3:2.5:1. All dental chaetae not differentiated, smooth, anterior chaetae only 1,1,2,3 seen, most basal one not seen.

Gut well-filled with pollen, fungal hyphae and spores, even possibly diatoms. A parasite seems to be present on femur of leg II.

Comment. The genus Katianna Börner, 1906, with type species, Katianna mnemosyne Börner, 1907, has as diagnostic characters: series of three or four erect, spines along the internal margin of each ocellus patch and on vertex, claw often with tunica on at least one pair of legs, finely clavate distal outstanding tibiotarsal hairs, external pretarsal setulae present, ventral tube with long, smooth sacs and mucro broad at base and tapering slightly, with at least one lamella toothed. The significant diagnostic characters of the family Katiannidae that are absent on K. coeruleocephala are spines on the head vertex, trochanteral organ, toothed lamella on mucro and outstanding, only slightly clavate, tenent hairs. None of these characters are present on the holotype of K. coeruleocephala. Instead, the characters of the claw, tibiotarsus, mucro, trochanter, chaetotaxy of head and male with dorsal spines on large abdomen and abdomen VI put this specimen in the family Bourletiellidae and genus Bourletiella. Furthermore, the yellow colour of the body, darker head and antennae, distal anterior chaetotaxy of the dens and arrangement, size and shape of male secondary sexual characters dorsally on abdomen VI identify the specimen as B. viridescens Stach, 1920.

As a result, I hereby synonymise, Katianna coeruleocephala Handschin, 1920 with Bourletiella viridescens Stach, 1920.

Note. The genus Katianna was erected by Börner (1906: p. 182) in a key to genera of Sminthuridae, Sminthuridinae:

“Genus Katianna nov. gen. (Typus: K. mnemosyne CB. = Sminthurus multifasciatus Parona! nec RT.)”.

He gave as characters: anal segment separate, mainly through a saddle joining genital segment and the furcal segment; genital segment being fused dorsally with it; each side with only one bothriotrix; tibiotarsus distally with outstanding, finely clavate, tenent hairs, antennal segment IV clearly subsegmented, dorsal mucronal edges as Fig. 5 (i.e. smooth or lightly toothed). He did not record a type locality nor provide a figure at this time. It was not until the next year that K. mnemosyne was formally described by Börner (1907). In this latter publication he marked it as a new species, gave a full description and included a type locality, La Plata, Argentina. It is not clear if Börner had additional material from South America of this species or if his description was based only on material identified by Parona in 1895 as Sminthurus multifasciatus from La Plata and not on fresh material. Ellis and Bellinger (1973) accept the type designation as valid.