Trichpetalum montis Chamberlin

Shear, William A., 2010, 2385, Zootaxa 2385, pp. 1-62 : 24-25

Trichpetalum montis Chamberlin

Figs. 23–25

Trichopetalum montis Chamberlin 1951:214 , figs. 13–15.

Types: Male holotype and male paratype from Gatlinburg, Tennessee, in USNM, examined. The USNM collection contains other specimens of montis labelled as from Gatlinburg and collected at the same time, but not labelled as types. The types were taken from a “grassy area” and a “spruce-fir area,” but not separately labelled as such. Assuming that Chamberlin was referring to a naturally occurring spruce-fir community (and perhaps to a grassy Appalachian “bald”), the nearest possible locality to the town of Gatlinburg would be about 10 road miles to the southeast, in the Great Smoky Mountains National Park , and at an altitude at least 3500’ (1067m) higher .

Diagnosis: The gonopod angiocoxite is distally expanded, deeply cleft, and bent dorsally, resembling T. uncum , but there is no lateral branch; the colpocoxite resembles that of uncum but differs in detail.

Etymology: The species epithet, montis, Latin , “of the mountains,” refers to the Great Smoky Mountains.

Male from “Gatlinburg,” Tennessee: Length, 4.5 mm, width, 0.40 mm. Color pale yellowish white. Ocelli 8, upper row of 6 strongly curved, lower row of 2 at midpoint of upper row. Legpairs 3–7 encrassate, pairs 4, 5 the largest. Gonopods ( Figs. 23–25) large for size of animal, with usual inflated sternum; coxae with scattered setulae not hairlike, culminating in distal coxal shoulder; single coxal seta shifted to lateral surface; angiocoxite large, broad, with group of 6 setae, sharply elbowed midlength, tip expanded, deeply cleft, ventral division 5 times broader in lateral view than dorsal. Fimbriate branch large, robust (truncated in drawings). Colpocoxite similar to that of T. uncum but with additional small teeth. Legpairs 10 and 11 with glands, telopodite of pair 10 slightly reduced.

Female from “Gatlinburg,” Tennessee: Length, 4.8 mm, width, 0.45 mm. Nonsexual characters as in male.

Distribution: Material examined: TENNESSEE: Sevier Co.: Gatlinburg, spruce-fir, 11 July 1947, H. Hanson, males, female (USNM).

Notes: Doubts about the actual type locality were expressed in the Types section above. The collection in July of mature specimens would further suggest that the real type locality is at a much higher altitude than the town of Gatlinburg. Hence I suggest Newfound Gap, easily accessible by highway from Gatlinburg.

Chamberlin’s figure of the gonopod (1951, his fig. 14) looks nothing like the gonopods of the specimens, and nothing like a Trichopetalum gonopod.

Four males were included in the collection I examined. Lengths given in the description are approximate because all specimens are fragmentary. Two of the males had large, orange structures attached to the gonopods and tenth legs; these are likely spermatophores, as discussed under T. dux , above, but were seemingly much more amorphous in form. The specimens had lost many legs and segmental setae, however, so it is possible rough handling has broken or damaged the supposed spermatophores.

Despite a significant collecting effort on spruce-fir peaks in the Great Smoky Mountains National Park and elsewhere in North Carolina and Tennessee by F. A. Coyle, myself, and others, Trichopetalum montis has never been recollected. Just to the southeast in North Carolina, the new species T. dickbrucei , quite different in appearance from montis , is the only trichopetalid that has been found. Trichopetalum dickbrucei has been taken at Newfound Gap, which place is suspected as the real type locality of T. montis . The new species, described below, is variable in the form of the tip of the angiocoxite, but the Newfound Gap specimens of dickbrucei do not look at all like montis , and montis gonopods are significantly outside the known range of variation of dickbrucei . Taken all in all, one has to wonder if the true provenance of the types of montis may be somewhere far distant from Gatlinburg, Tennessee, and if they were grossly mislabelled. On the other hand, aside from the lack of a lateral branch, the gonopods look a good deal like those of uncum , which occurs at lower elevations in eastern Tennessee.