Bryobia cinereae, Auger & Migeon, 2014

Auger, P. & Migeon, A., 2014, Three New Species Of Tetranychidae (Acari, Prostigmata) From The French Alps (South-Eastern France), Acarologia 54 (1), pp. 15-37 : 16-21

Bryobia cinereae n. sp.

( Figures 1-3 )

Type-specimens — Holotype (female), 3 female paratypes on 4 microscopic preparations from Genista cinerea (Vill.) DC. (Leguminosae) , cime de Braus (43.875°N 7.394°E, alt. 1040 m), LucØram, France, 23-VII-2009, leg. P. Auger. All the material housed in the Institut National de la Recherche Agronomique ( INRA) collection of the Centre de Biologie et de Gestion des Populations ( CBGP), coll. Auger-Migeon N ° 1754 for holotype and 1755-1757 for paratypes, 34988 Montferrier-sur-Lez , France.

Diagnosis — Limited anterior dorsal propodosomal projections over the gnathosoma, prodorsal lobes scarcely developed, vertical setae (v 1 and v 2) inserted in tubercle-like structures. Dorsal setae elongated, quite stout, serrate, inserted on tubercles and subequal in length on hysterosoma. Empodia provided with two rows of tenent hairs.

Description:

Female: Holotype 495 µm long (excluding gnathosoma) gnathosoma 94 µm long (measured to the tip of palps), width 315 µm. Three paratypes measured, 452 – 498 µm long, gnathosoma 94 µm long, width 305 µm.

Dorsum — Prodorsum with four pairs of setae and with weakly developed anterior lobes ( Figs. 1A , 3A ). Outer propodosomal lobes small, about 10 µm, more or less similar in length to dorsal tubercles; inner lobes smaller about 5 µm (measured from the bottom of the incision between the inner lobes). Propodosomal lobes with basal width about 67 µm, distance between v 1 setae insertions about 13 µm. Incision between median lobes shallow. First pair of propodosomal setae (v 1) less than half the size of the second pair (v 2). A horizontal line joining tip of v 1 setae located on the inner lobes crosses v 2 setae about their three-quarters. Dorsal body setae not spatulate, elongated, moderately stout, serrate, inserted on tubercles, subequal in length with the exception of v 1 setae far smaller ( Figs. 1A, 1B ). Dorsocentral setae (c 1, d 1 and e 1) shorter than distances between consecutive setae (length of holotype and variations of three paratypes): v 1 17 (14 – 15); v 2 40 (38 – 42); sc 1 50 (48 – 52); sc 2 50 (50 – 58); c 1 53 (56 – 58); c 2 51 (53 – 54); c 3 46 (47 – 51); d 1 50 (51 – 55); d 2 58 (61 – 63); d 3 64 (63 – 71); e 1 50 (54 – 58); e 2 61 (60 – 71); e 3 63 (64 – 67); f 1 60 (63 – 66); f 2 61 (58 – 66); h 1 47 (53 – 55). Distances between setae: c 1 - c 1 52 (54 – 55), d 1 - d 1 33 (31 – 32), e 1 - e 1 17 (20 – 24), c 1 - d 1 85 (87 – 99), d 1 - e 1 60 (64 – 66). Sacral setae (f 1 and f 2) in marginal position and contiguous. Dorsal surface wrinkled, on propodosoma irregular medially and mostly longitudinal laterally, transverse on hysterosoma, more or less arched in the distal part comprised between e 3 and h 1 setae. Area immediately anterior to h 1 setae with fine arched longitudinal reticulation.

Gnathosoma — Stylophore rounded, slightly indented (slightly emarginate anteriorly), longer than wide. Tibial claw of palpus bidentate ( Fig 3B ). Palptarsus slightly elongated, about 18.5 (19.2) long with six setae and one solenidion. Eupathidia ul’ ζ, ul” ζ slightly shorter than su ζ, solenidion short. Peritreme anastomosed distally in a relatively long and slender enlargement: length 33 (26 – 28), width 8.5 (9 – 10) ( Fig. 3C ).

Venter — Striation transverse between 1 st (1a) and 2 nd (3a) pairs of setae becoming irregularly longitudinal (broken medially) between 2 nd and 3 rd (4a) pairs of setae and transverse between 3 rd and aggenital (ag) pairs of setae. Area immediately anterior to genital flap with irregular longitudinal striation, V-shaped between ag setae ( Fig. 3D ). Sacculus of spermatheca oblong (shape variations due to mounting) ( Fig. 3E ). Three anal and two para-anal setae.

Legs — Length inferior to body length. Leg I 308 (299 – 312) µm long (length of holotype and variations of three paratypes, measured from trochanter to tarsus), leg II 222 (220 – 227), leg III 219 (212 – 219), leg IV 250 (240 – 250). Length of segments of leg I as follows: trochanter 21 (22 – 24), femur 99 (90 – 96), genu 49 (49 – 53), tibia 61 (62 – 66), tarsus 75 (75 – 79). Leg setal count as follows ( Figs. 2 A-D):

I 2 - 1 - 8 [9] - 4 - 8 [7] + (1) - 17[16] + (2) + 2 duplexes; II 1 - 1 - 5 - 4 - 3 [5] - 14[13] + (2) + 1 duplex;

III 1 - 1 - 4[3] - 2 [3] - 4[5] - 12[11] + 1 duplex;

IV 1 - 1 - 4 [3]- 2 - 4 [3-5] - 13[12-14] + (1).

Tarsus III associated setae serrate and approximate with solenidion forming duplex, the tactile member slightly longer and proximal ( Fig. 2E ); tarsus IV with solenidion well-separated from tactile, proximal, about one third the length of tactile ( Fig. 2F ). True claws uncinate, with one pair of tenent hairs, empodial pads each bearing two rows of tenent hairs ( Fig. 2G ).

Male: Unknown

Etymology — The specific epithet cinereae refers to the species name of the host plant on which mites were collected.

Remarks — The combination of prodorsal lobes poorly developed and dorsal setae not spatulate but elongate with dorsocentral setae inferior in length to the distance between consecutive setae brings this species close to B. sarothamni Geijskes, (1939) , B. longisetis Reck, (1947) , B. artemisiae Bagdasarian (1951) , B. variabilis Manson, (1967) and B. serifiotica Hatzinikolis, Papadoulis and Kapaxidi (2007) . It can be distinguished from B. sarothamni by the dorsal hysterosomal setae which are lanceolate, shorter, variable in length (h 1 the largest) versus elongate and subequal in length in B. cinereae . Bryobia longisetis can be separated from B. cinereae by the propodosomal inner projection which is more developed, by medial lobes which are almost fused, by f 1 and f 2 dorsal setae which are not contiguous and by a different leg chaetotaxy. In B. variabilis (the form bearing long, slender and serrate dorsal setae) the leg setal formula is different and dorsal setae are slender, variable in length (c 2, c 3, d 1 and d 2 being much smaller) whereas quite stout and subequal in length in B. cinereae . Bryobia serifiotica differs from B. cinereae by the dorso hysterosomal setae larger in the latter, by the difference in size of the vertical setae (v 1 slightly inferior to v 2 in B. serifiotica vs. v 1 up to three times smaller than v 2 in B. cinereae ), by the position of f 1 setae (more or less in normal position and well separated in B. serifiotica whereas f 1 and f 2 are in marginal position and contiguous in B. cinereae ) and by the solenidion of the tarsus IV (associated with a tactile setae but well separated and proximal in B. serifiotica and B. cinereae respectively). Depending on the literature referred, B. artemisiae is more or less close to B. cinereae . In the original description by Bagdasarian (1951), prodorsal lobes are similar in the two species but vertical setae (v 1 and v 2) are subspatulate to spatulate (elongate in B. cinereae ) and dorsal hysterosomal setae are short and fan-shaped (elongate in B. cinereae ). According to Reck (1959), dorsal setae of B. artemisiae vary from short spatulate to slightly elongate and, in his drawing, v 1 and v 2 setae are elongate and lanceolate (only elongate in B. cinereae ). Wainstein (1960) mentions that dorsal setae are narrowly spatulate and almost elongated. In Livshitz and Mitofanov (1971) and Mitrofanov et al. (1987) the drawing of B. artemisiae in habitus resembles to B. cinereae : prodorsal lobes are small, v 2 are longer than v 1, dorso hysterosomal setae are elongate and inserted on tubercles. However, v 1 and v 2 setae are spatulate and subspatulate (narrow in B. cinereae ), dorso central setae (c1, d 1, e 1) are longer to dorso lateral (similar in length in B. cinereae ) and the leg setal count is different.

Figures

FIGURE 1: Bryobia cinereae n. sp., female: A – dorsal aspect; B – dorsal h1 seta.

FIGURE 2: Bryobia cinereae n. sp., female: A – tarsus and tibia I; B – genu and femur I; C – tarsus and tibia II; D – genu and femur II; E – duplex setae on tarsus III; F – solenidion and associated tactile seta on tarsus IV; G – empodia I-IV.

FIGURE 3: Bryobia cinereae n. sp., female: A – prodorsal lobes; B – Palpal tibia and tarsus; C – peritremal distal anastomosis; D – anterogenital striation; E – spermatheca (variations between preparations).