V. L. Kellogg and Shonosuke Nakayama.
A New Trichodectes from the Goat.
Psyche 22:33-35, 1915.

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PSYCHE
VOL. XXII APRIL, 1915 No. 2
A NEW TRICHODECTES FROM THE GOAT.
BY VERNON L. KELLOGG AND SHONOSUKE NAKAYAMA, Stanford University, California.
The domestic goat has long been known to harbor a Mallophagan (biting louse) species wculiar to it and to one or two related wild forms, most notably the chamois. This parasite, Trichodectes climax, was recognized by Nitzsch a century ago, and has since been recorded from domestic goats in all part of the world. It is a cosmopolitan parasite species because its host is cosmopolitan. Also it is the only Trichodectes until now found on the domestic goat. It is characteristic of the goat just as another Tricho: dectes species, sphcerocephalus, is characteristic of a certain nearly related host, the domestic sheep and two or three of its wild con- geners, (Ovis ornata, 0. melanocephala, et al.). So far sheep have not been found to harbor any other Mallophagan than T. spharo- cephalus.
But the goat, at least certain individuals of the merino goat, living in California, do afford food and shelter to another and larger species of Trichodectes than the long-known and widespread climax.
This species we are describing in this paper. The specimens of the new species (many males and females) were received this month (November) from Professor W. B. Henns of the University of California, who took them from a "young merino goat received from near Inverness, Marin County, Cali- fornia." Professor Herms reports the goat as "very badly in- fested," adding in a later letter, that he has "never before seen an animal so badly infested with biting lice as is the goat in our pos- session, and I am told other goats in the flock from which this one was taken are equally infested."
The new species is unusually large for a Trichodectes, the fe- males being more than two millimeters in length (some individuals almost 2+ rom.), the males not quite so long. T. climax hardly Pu&e 22:33-15 (1915). hup Ytpsychu einclub orgt22/22-011 html



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34 Psyche [April
attains a length of .one and a half millimeters. In the shape of
head and abdomen, the curious covering of short, fine spiny hairs, and in the markings, the new species of differs strongly from climax. It shows more of a resemblance, in shape and markings of head, and general appearance of body to T. penicillatus than to any other species of the genus, which resemblance, if it suggests any near relationship-it probably does not-is most extraordinary, as penicillatus has been recorded only from a kangaroo! However, it has been recorded but once, and that by Piaget, its describer, who had his specimens from a single kangaroo (Macropus penicil- latus) in the Zoological Garden at Rotterdam. Zoological garden
specimens of Mallophaga are always open to suspicion as to the host records, the conditions, especially in such a crowded garden as I remember the Rotterdam one to be, being unusually favorable for straggling. However, the resemblances between T. penicillatus and our new species from the goat may be only superficialand non- significant of relationship. The new species may be described as follows :
Trichodectes herrnsi sp. nov. (Fig. 1).
Many males, females and young from a young merino goat, Inverness, Marin Co., Calif. (coll. W. B. Herms).
Female: Body, length 2.4 mm., width (widest across fifth abdominal segment), 1.32 mm., head, length -44 mm., width .57 mm. General color pale yellowish brown,
the head and thorax and the median abdominal blotches darker than the almost whitish ground color of the abdomen. Dorsal surface of the whole body with a sparse covering of short, fine, spine-hairs. In addition there are longer hairs along the lateral margins and in regular segmental transverse series on the abdomen. The head is broader than long, the region behind the antennae being distinctly and suddenly broader than the part in front. The clypeal margin is flatly convex, and the occipital margin shallowly concave. The antennae are long enough to reach, if bent directly backward, to the hind lateral angles of the head, but no farther than that. The head is uni-colored, showing no markings except the slightly darker narrow margin all around, and a pair of short, distinct narrow bands (more like small linear blotches) extending from base of antennae to the clypeal margin, Several not long hairs in each temporal angle and the whole head sparsely covered with short, fine spine-hairs.
Prothorax with sharply produced, conspicuous lateral angles, with a group of five or six rather strong, although not long, hairs in each angle. It is much wider than long, as is also the metathorax which is about the same width as the prothorax, but is a little longer. The metathorax has a doubly angulated posterior margin, with the median portion concave. There are numerous longish stiff hairs along the pos- tero-lateral margins of the segment, and a transverse dorsal series of a dozen or



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19151 Kellogg and Nakayama-A New Trichodectes . 35 more hairs across the segment near the posterior margin. The legs have the single tarsal segment unusually long and distinct, and the tibiae bear numerous short but distinct and sharp spine-hairs.
The abdomen is large and thick, symmetrically elliptical with broad ends, and covered sparsely with minute pointed spine-hairs. There is also a transverse series
of longer but fine spine-
hairs across the dorsal
surface of each segment
just in front of the pos-
terior margin of the seg-
ment. There are numer-
ous longer hairs on the
lateral margins of each
segment, and a brush of
longish hairs on the pos-
terior margin of the last
segment. At each side of
the next to last segment
there is a chitinized back-
ward-projecting, pointed
process, slightly curved
and angulated in the
middle, with the con-
vexity on the outside.
The ground color of the
whole abdomen is pale
yellowish-white, of more
golden color along the
lateral margins, and with
a series of seven brownish
median blotches, largest
and darkest on segments
Fig. 1.
Trichodectes her& n. sp.; A, female; B, last 7 and 8. The next to the
antenna1 segment of female, showing sense pits; C, last segment is nearly
small chitinized sclerite at middle of occipital margin covered by two
of head of male; D, same of female; E, outline of head translucent, brownish
of male; F, hind leg of female;
G, part of abdominal
blotches, partly fusing
body-wall showing scaly covering; H, tip of abdomen on their inner faces.
of male, showing genitalia; I, tarsus and tarsal claw of length hind leg of female.
1.68mm.. width .61 mm.,
head, length .34 mm.,
width .47 mm,; thus much smaller than the female, and with abdomen with sides more nearly parallel, converging posteriorly. The head is a little different in shape, the anterior, or clypeal, portion not extending so far in front of the antennae and more flatly rounded. The genitalia show distinctly through the body-wall, although they are not heavy or strongly chitinized. The parameres are long, narrow and pointed.




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