Blattophila peregrinata n. sp.

(Figs. 2 A–F; 3E–H; Table 2)

Description (based on 16 males, 70 females). Male: Small worms. Narrow lateral alae present, extending from point of esophageal corpus to precloacal region (Fig. 3 F). Head region slightly expanded. Esophagus with base of corpus slightly expanded, thin isthmus, and elongate bulb (Fig. 2 E). Nerve ring posterior to base of corpus. Excretory pore posterior to esophagus. Four pairs of caudal papillae present, including one larger pair subventral precloacal, one smaller pair postcloacal papillae spaced closely together, one adanal pair, and one small pair at base of filiform tail appendage (Fig. 2 F). Spicule present. Gubernaculum absent.

Female: Oral opening triangular, 8 weakly developed myolabia present, each with a rounded distal end and linear elevated cuticular division between the two borders of each myolabium (Figs. 2 C, 3E). Amphids circular. Second annule longer and markedly wider than oral annule, base delineated from rest of body (Fig. 2 B). Lateral alae absent. Esophageal corpus with slightly rounded, expanded anterior portion surrounding the stoma. Posterior of corpus expanded, gradually narrowing toward anterior end (Fig. 2 B). Nerve ring near posterior end of corpus, at point where corpus expands basally (Fig. 2 B). Isthmus short, straight. Basal bulb spherical with valvular apparatus. Excretory pore posterior to esophageal bulb. Didelphic, opisthodelphic. Vulva opening in anterior third of body, vagina posteriorly directed (Fig. 2 A). Vulva opening crescent-shaped, lacking prominent extension of cuticle. Common uterus branching posterior to mid body, ovaries reflexed anteriorly. Tail subulate, slightly filiform (Fig. 2 D). Rectal glands present. Eggs oval, with operculum (Figs. 3 G, H).

Taxonomic Summary

Type host: Periplaneta australasiae (Fabricius, 1775) (Blattaria: Blattidae)

Type locality: Moore Greenhouse, campus of Ohio Wesleyan University, Delaware, Ohio, USA. (40˚17’43.1”N 83˚03’55.3”W).

Prevalence = 79.5%; mean intensity = 6.43

Other localities (from P. surinamensis only): John Pennecamp Coral Reef State Park, Key Largo, Florida, USA (25 ̊7’38.3”N, 80 ̊24’31.2”W); Prevalence = 79%; mean intensity = 2.15; Galápagos Islands, Ecuador (locality information for specific islands in Sinnott et al., 2015). Prevalence (in Galápagos P. surinamensis) = 16%; mean intensity = 1.5

Site of infection: hindgut

Specimens deposited: From P. australasiae: holotype female, HWML 99918; allotype male HWML 99919; paratypes, 20 females HWML 99921.

From P. surinamensis: vouchers, four females HWML 99920, 1 male HWML 99922 from John Pennecamp Coral Reef State Park, Key Largo, Florida, USA.

Voucher DNA sequences: 18S small subunit ribosomal RNA gene, partial sequence GenBank accession number KX752427. 28S ribosomal RNA gene, partial sequence GenBank accession number KX752428.

Etymology. The name “ peregrinata ”, or “traveler”, refers to the widespread distribution of this species.

Remarks. Based on keys to the genus Blattophila by Farooqui (1967), Ali et al. (1970), and an updated key by Jex et al.,(2005), Blattophila peregrinata n. sp. differs from Blattophila suppelaima Basir, 1941, Blattophila singhi Farooqui, 1967, Blattophila indica Rao & Rao, 1965, Blattophila farooquii (Farooqui, 1967) Adamson & Van Waerebeke, 1992, and Blattophila bryostriae Farooqui, 1967 in having a posteriorly directed vagina. In each of these species, as well as in Blattophila basiri (Ahmed & Jabin, 1966) Adamson & Van Waerebeke, 1992, a species not included in published keys, the vagina is anteriorly directed. Females of B. basiri, B. bryostriae, and B. farooquii have lateral alae and males of these species differ, being larger (970–1000 µm in B. bryostriae, 1030 – 1200 µm in B. farooquii and 1800–2100 µm in B. basiri vs. 275–510 µm in B. peregrinata n. sp.) and having only a single postcloacal papilla at the base of the tail (Ahmed & Jabin, 1966; Farooqui, 1967). The male tail appendage is shorter in these species (19–29 µm in B. basiri vs. 28–43 µm in B. peregrinata n. sp.). Females of B. singhi also have lateral alae and a laterally tilted cephalic region. Females of B. supellaima lack a well delineated second annule and do not have as broad a corpus base (17–40 µm vs. 38–58 µm) as in B. peregrinata n. sp. (Basir, 1941). The eggs of B. supellaima lack an operculum. Females of B. indica also have a narrower corpus base (33 µm) and lack operculate eggs, and males are larger (1016 µm). The posterior tail shape of males differs from that of B. peregrinata n. sp. in being rounded rather than gradually tapering (Rao & Rao, 1965).

Of the remaining species, Blattophila narayani Farooqui, 1967, and Blattophila javanica Chitwood & Chitwood, 1934 have the vulva located near the midbody rather than at its anterior third. Blattophila narayani females have lateral alae, and the male tail appendage extends from an abruptly ending, rounded tail tip. Blattophila javanica has a longer esophagus (length 410–610 µm) and tail length (590–670 µm). Based on the illustrations of the female by Chitwood and Chitwood (1934), the base of the corpus is also wider (estimated as 70 µm from Fig. 2 in Chitwood & Chitwood, 1934) than in B. peregrinata n. sp.

Three additional species, Blattophila perisphoeriai Ali, Farooqui, & Shrisunder, 1970, Blattophila aurangabadensis Ali & Shrisunder, 1971, and the type species, Blattophila sphaerolaima Cobb, 1920 have the vulva located in the anterior third of the body, as in B. peregrinata n. sp. Blattophila perisphoeriai differs in lacking cephalic annules and B. aurangabadensis has eggs without an operculum. Blattophila peregrinata n. sp. has prominent cephalic annules and has operculate eggs. Measurements for many characters of B. perisphoeriai females (body length, width, esophagus, excretory pore, distance of vulva from anterior end, and egg length) are similar to those of B. peregrinata n. sp., and the base of the corpus is not prominently rounded (Ali et al., 1970). However, the tail of B. peregrinata n. sp. is longer than that of B. perisphoeriai (200–240 µm in the latter) and tapers somewhat gradually rather than abruptly narrowing from the end of the body. There is not a prominent second cephalic annule in B. perisphoeriai. Blattophila sphaerolaima resembles B. peregrinata n. sp. in having an enlarged second annule, a slightly expanded distal portion of the corpus surrounding the buccal cavity, and operculate eggs (Jex et al., 2005). However, the eggs are larger (84–100 µm) and there are two polar opercula in B. sphaerolaima, and the female has lateral alae. Tail length (800 – 1140 µm) is also considerably larger than in B. peregrinata n. sp.

The most recently described species, B. praelongicauda Jex, Schneider, Rose, & Cribb, 2006, another species with operculate eggs, has a much longer tail (seen by actual length 800–820 µm and De Man ratio c 2.3–2.4) and has a corpus whose base is more rounded than that of B. peregrinata n. sp.