Phyllozetes subiasi, Jorrin, 2014

Jorrin, J., 2014, Two New Arthronotic Mites From The South Of Spain (Oribatida, Cosmochthoniidae), With A New Subgenus And Species Of Cosmochthonius And One New Species Of Phyllozetes, Acarologia 54 (2), pp. 183-191 : 187-189

Phyllozetes subiasi n. sp.

Diagnosis — Mite species belonging to Phyllozetes , with the rows of foliar notochaetae e-f spiniform, with the margins and dorsal surface of the leaf covered by strong spines.

Description Adult ( Figure 2 ) (n=1) General aspect, measures and integument ( Figure 2 ) — Small and narrow oribatid, the idiosomal length is 264 micrometers, 2.30 times its maximum width. The cuticle is clear and colorless, the surface of the integument in the pygidium and the pleural plate is microfoveolated, rest of the integument apparently smooth.

Prodorsum ( Figure 2a ) — Rostral tectum with small perforations in longitudinal rows of 1-4 alveoli. Setae of the proterosoma with the growth and pubescence typical of the genus. The rostral setae (ro) are the biggest ones, uniramous and densely pubescent. The lamellar setae (la) are biramous with a ’V’ shape, the two pairs of exobothridial setae (exa and exp) are setiform with large pectinations, with exp being the lower prodorsal seta; the interlamellar setae (in) are in a interbothridial position next to the bothridia; the sensilli (ss) are typical of the family, fusiform and densely pectinated in its front half.

Notogaster ( Figure 2a ) — The anterior plate NA is approximately 1.5 times wider than posteriors (NM1 and NM2) and 4 times narrower than the pygidium. The anterior notogastral fissurae ar1 is the broadest and it shows a middle ridge or suture, which reflects an added extension of the anfiarthrosis at this level, as can be observed in the lateral view of the mite ( Figure 2c ). The setae on NA (c1, c2, c3 and cp) are typically setiform in the genus, approximately equal in length. Each one projects towards the base of the posterior seta, c1 to c3 are equidistant and are aligned in the center of the segment and cp in the posterior corners. In NM1, the setae d2 are somewhat shorter than those of c- series and d1 is the shortest seta; pairs d1 and d2 are joined by a narrow crease in the first notogastral furrow, with the distance between d1 being approximately half of the d1–d2 distance. The erectile setae e-f originate from narrow intercalary sclerites: they are equally long and they end over the other side of the hysterosoma, they are spear-like, the base part quickly sharpens in the long narrow anterior part which occupies two thirds of the setal length, each seta possesses a strong central nerve which doesn’t branch out, the margins and dorsal face of the setal sheet are densely covered by long, strong spines ( Figure 2d ). Setal rows h and ps are posterior and marginal in the pygidium, h1–h3 shifted to dorsal position and ps1–ps3 to ventral position, all setae are medium long and densely plumose.

Lateral View ( Figure 2c ) — Below the NA plate is located a small triangular plate PLa, with the lyrifissure ia and which includes a small concave triangular humeral flap (hfl). Below hfl and over the acetabulum III, two small accesory plates are marked (apl1 and apl2), auriculiform and prominent in the ventral view and with the inferior plate (apl2) overlapping the dorsal one (apl1). On top of the acetabulum IV, there is a small cribriform plate (apl3), whose surface appears to be dotted; below and attached to the two median notogastral plaques and pygidium there is the long plate PLm, which has the cupule im on its anterior angle and whose surface is covered with fine foveoles.

Venter ( Figure 2b ) — Epimeral plates separated; coxisternal formula I-IV: 3-2-3-4, the epimeral setae are relatively short and setiform, with separate pectinations. Large genital plate, each value with 10 pairs of setae spread out in two longitudinal rows, 6 medial ones and 4 longer lateral ones with the third and fourth setae somewhat more medial in this row. Four pairs of anal setae similar to the genitals. Adanal plate, posteriorly coalescent with a ’U’ shape and with four pairs of relatively long setae, more pubescent than the anal ones.

Legs — Tarsi I to IV with claw formula 2-2-2- 3 and with the corresponding lateral claws thinner and sligthly curved downward.

Specimens examined — One female, holotype cod. 2716-Hol/M43-20120523; in soil below the coverage of an isolated olive tree next to a small formation of holm oak trees ( Quercus ilex ), next to a plot of an organic olive grove.

Etymology — The specific name ’ subiasi ’ is dedicated to the Spanish oribatologist Luís S. Subías.

Remarks — The genus Phyllozetes possess a characteristic lanceolated erectile setae of fringed margins with cilia that is more or less long and narrow and a surface that is either smooth or covered with minute cilia. Phyllozetes subiasi n. sp. differs from the congeneric species as it is the only species that grows strong spines, both on the rims as well as the upper face of the setal sheet.

Figures

FIGURE 2: Phyllozetes subiasi n. sp.; a – dorsal view, b – ventral view, c – lateral view, d – detail of seta e1; gnathosoma and legs not illustrated. Scale bar (Figs. 2a-c) = 100 micrometers.