After Andrássy (1958)
MEASUREMENTS
Holotype male: L = 1.35 mm; a = 32; b = 7.5; body width = (37) µm; spear = (15) µm; pharynx = (180) µm; tail = (45) µm; c = 30; c’ = (1.4); spicules = 39 µm; gubernaculum = 10 µm.
DESCRIPTION
Female. This species was described based on a male and a juvenile; the female was not found. The juvenile is similar to male (see below) in general appearance and diagnostic characters, except that the intestine does not extend into the tail region. The juvenile has a body about 1 mm and a tail about 40 µm long.
Male. Cuticle with fine transverse annulation. Lip region widely rounded, continuous with the body contour. Spear as long as lip region diameter, with well-developed basal knobs. Pharynx with a narrow anterior part and a pyriform posterior part. Intestine frequently granulated; the posterior end extending into the tail region. Spicules curved, with small proximal processes. Gubernaculum about one-fourth of spicule length. Musculature around the spicules well developed. Five spaced precloacal supplements visible, located relatively far apart, and one other posterior to the cloaca. Tail short, bluntly rounded, equipped with caudal gland, the duct of which opens at its terminus.
DIAGNOSIS AND RELATIONSHIPS
Tylolaimophorus bulgaricus has been differentiated from T. cylindricus on the basis of the number of ventromedian precloacal supplements (five vs one) and the presence of an internal terminal peg, which is not known in T. cylindricus. Brzeski (1994) explained that the number of supplements is not considered as a specific character because of the limited visibility of these organs in some specimens. He also emphasized that different numbers of supplements may be observed in different individuals or populations of the same species, as has been reported in T. typicus, T. pileatus and T. constrictus. Considering intraspecific variability in the number of supplements and presence of an internal terminal peg, he concluded that the identity of T. bulgaricus and T. cylindricus cannot be excluded. Andrássy (2009) didn’t accept this synonymy and still considered T. bulgaricus as a valid species.
DISTRIBUTION
Described from the rhizosphere of fruit trees in Bulgaria ( Andrássy 1958). It has been reported from strawberry fields in Kostinbrod, Bulgaria ( Katalan-Gateva & Nedelchev 1983). Kuzmin & Gagarin (1990) noted that this species occurs in Taymyr and Severnaya Zemlya, Russia. Another population was reported in association with forests ( Quercus frainetto Ten.) in Rhodopes, Bulgaria ( Peneva et al. 2011). Unfortunately, morphological or morphometric data were not provided in these studies.