Ochrogramma Gardner and Shelley, 1989

Ochrogramma Gardner and Shelley, 1989 View in CoL

Ochrogramma Gardner and Shelley 1989: 194 View in CoL .

Type species. Ochrogramma formulosa Gardner and Shelley, 1989 , by original designation.

Notes. Ochrogramma View in CoL is superficially similar to Vasingtona View in CoL . Males of the species of Ochrogramma View in CoL are usually smaller (10–15 mm) than those of Vasingtona irritans View in CoL (16–22 mm). In our new interpretation of the gonopods in this subfamily, Ochrogramma View in CoL is distinct from Vasingtona View in CoL in having many fewer arborescent processes on the gonopod ( Fig. 19 View Figures 17–20 , 23, 24 View Figures 21–24 )—two species of Ochrogramma View in CoL may have none—in the reduced and perhaps sometimes absent telopodite (t, Fig. 20 View Figures 17–20 ), having a rodlike posterior angiocoxite (pac, Fig. 20 View Figures 17–20 ), and a prominent posterior lobe of the colpocoxite. The hypothesis that the colpocoxite originates from the coxal gland of the eighth legpair is supported by the relatively poorly sclerotized colpocoxites emerging from distinct sockets in this genus (cc, Fig. 20 View Figures 17–20 ). Gonopod structure is similar among the species, but two of them, O. formulosa Gardner and Shelley, 1989 , and O. heterogona Gardner and Shelley, 1989 View in CoL , seem to lack the arborescent processes (“spicules” of Gardner and Shelley) on the anterior surfaces of the anterior angiocoxites. We have not seen specimens of these species. Ochrogramma bentona View in CoL has the most complex gonopods in the genus while those of O. haigi View in CoL , O. formulosa and O. heterogona View in CoL are progressively simpler. Gardner and Shelley (1989) did not give length measurements for females, but we found that females are typically longer than males (17–19 mm in O. bentona View in CoL ). The dorsal yellow stripe typical of the subfamily may be suppressed entirely in Ochrogramma species males, or present only on posterior rings.

The gonopod telopodite is seen in only two of the species, O. bentona View in CoL and O. formulosa . It is highly reduced and rodlike (t, Fig. 20 View Figures 17–20 ), articulating about one-third of the way distal on the anterior angiocoxite and terminating in several filaments which are likely modified setae. The posterior angiocoxite, evidently missing in O. heterogona View in CoL , is roughly similar in form to the telopodite (pac, Fig. 21, 22 View Figures 21–24 ). Flagellocoxites are present in all species and are filamentous and branched (f, Fig. 21 View Figures 21–24 ).

Ochrogramma View in CoL was considered by Gardner and Shelley (1989) to be distributed entirely to the south of the Columbia River , but this was an artifact of insufficient collecting in Washington. Ochrogramma bentona (Chamberlin, 1952) View in CoL , extends north of the river to the Puget Sound region and Ochrogramma skamania n. sp. is from west central Washington. The other three Ochrogramma species are limited to small areas of Oregon and northern California ( Gardner and Shelley 1989, Fig. 220).

The meaning of the name Ochrogramma View in CoL was not discussed by Gardner and Shelley (1989). Both parts of the name come from Greek; ochros a prefix meaning “yellow” and gramma, referring to a “line, writing or drawing” (the root of English words such as grammar, graphics, telegraph, etc.). The combination likely refers to the dorsal yellow stripe.