Amplaria californica ( Cook, 1899 ) Shear & Marek, 2024

Shear, William A. & Marek, Paul E., 2024, The millipede family Striariidae Bollman, 1893. IX. The identity of Striaria californica Cook, 1899, and the new genus Bayaria for Striaria nana Loomis, 1936, with a key to genera and an annotated checklist of the Striariidae (Diplopoda, Chordeumatida, Striarioidea), Zootaxa 5463 (4), pp. 524-544 : 525-529

Amplaria californica ( Cook, 1899) , new combination

Figs 1–10 , 18, 19

Striaria californica Cook, 1899: 675 ; Loomis 1936: 409; Causey 1958: 181; Hoffman 1999: 208.

Type: Female holotype ( USNMNH Type #776) from “ California;” no further locality data. Cook speculated that the type was collected “probably near Sausalito” but gives no evidence for thinking so .

Diagnosis. The gonopods, secondary sexual characters of the males, and nonsexual characters are consistent with the genus Amplaria Chamberlin, 1941 , and the species is transferred to that genus as Amplaria californica ( Cook 1899) new combination. Amplaria californica is distinct in its greater length from other species of Amplaria (14–18 mm long, as opposed to at most 12 mm in other species). Only Amplaria shastae (Causey) is longer at 25 mm or more. Details of the gonopods serve as the primary means to distinguish A. californica from other taxa ( Figs 7, 8 , 18, 19 ).

Descriptive notes. Loomis (1936) provided a detailed description of the male, which we supplement here with illustrations and discussion of the gonopods and some other characters. A female is illustrated in Fig. 10 .

Modifications of the head and anterior legs of males are in most ways typical of species of Amplaria , but the acute lobes and serrate edges of the mandibular stipes are not present. The corners of the labrum are drawn out into slightly sinuous, acute processes (ls, Fig. 1 ). The first legpair ( Fig. 2 ) bears long, twisted spatulate setae ( Fig. 3 ) on the postfemora and tibiae, with a few distally on the femora. The first and second legpairs are similar in size and not reduced. The second coxae (cx2, Figs 4, 5 ) are enlarged, with wide openings of the vas deferens (vd) subtended by long setae, and the second prefemora (pf2) have distal knobs with a tuft of even longer setae. The third legpair ( Fig. 6 ) is typical of Amplaria , with the coxae bearing long flasks (cf) equal to or surpassing the prefemora (pf3) in length and with curled, decumbent apical setae on the anterior surface; the telopodites are not reduced. The pleurotergal edges of the fourth ring extend into processes overlapping in the midline behind the third legs (pcb, Fig. 6 ). The ninth legpair coxae ( Fig. 9 ) have short, blunt, mesal processes (cp) and the telopodites (t) are broadly flattened in the typical striariid manner.

Gonopods. The sternum (s, Figs 7 , 18 ) and coxa (cx, Figs 7 , 18 ) are well sclerotized. The coxae and sternum are free from each other. In lateral view ( Figs 7 , 18 ), the poorly sclerotized posterior lobe of the colpocoxite (cc) conceals most of the other structures, but it is clear that there are three branches of the flagellocoxite (f) sheathed by the posterior branch of the angiocoxite (pac). In mesal view ( Figs 8 , 19 ) the tip of the anterior branch of the angiocoxite (aac) can be seen to be truncate and simple, and the posterior branch (pac) arises from a strongly curved pedicel.

Females ( Fig. 10 ) are 15–18 mm long and like the males in nonsexual characters.

Records. Loomis (1936) reported this species from “ Santa Cruz Mountains [ Santa Cruz / Santa Clara Cos. , California],” Cordelia (Solano Co.) and Davenport ( Santa Clara Co. ). Only the Davenport specimens could be located in the USNMNH collection. Causey (1958) had a large female specimen (18 mm) from Lagunitas (Marin Co.). All these previously reported localities are consistent with a distribution around and north and south of San Francisco Bay. We cite the following new localities as consistent with the specimens determined as this species by Loomis (1936).

CALIFORNIA: Alameda Co.: Woolsey Canyon, Berkeley , 37.875°, -122.250°, 21 December 1965, T. Briggs et al., m ( CAS) . Contra Costa Co.: Mitchell Canyon , 37.920°, -121,941°, 20 May 1961, R. Brown, m, f ( CAS) . Marin Co.: McClure’s Beach, Point Reyes , 38.187°, -122.965°, 17 October 1965, K. Lee, B. Owyang, m ( CAS) ; Mill Valley , 37.906°, -122.545°, J. Helfer, mm, ff ( CAS) . San Francisco: Golden Gate Park , 37.769°, -122.486°, 15 September 1965, P. Rubtzoff, mm ( CAS) ; below Municipal Pier at foot of Van Ness Avenue , 37.807°, -122.426°, O. Owyang, m ( CAS) . Santa Cruz Co. : Davenport , 37.016°, -12.199°, 21 February 1929, O. F. Cook, m, f ( USNMNH) .

Notes. The female type of S. californica was examined by us for this study. The type is in poor condition, fragmented, and at one time was probably pinned and dried (two insect pins are in the type vial), but all or nearly all of the individual is present. Unfortunately, though the type has the appearance of a species of Amplaria Chamberlin, 1941 , at the present time it is not possible to separate species in that genus based on females alone. A second complicating factor is that the locality label reads only “ California, Capt. Casey” without further data.

Thomas Lincoln Casey, Jr. (1857–1925) was an army officer and entomologist who collected insects and other natural history specimens at the various places he was stationed. Casey was a Captain of Engineers and stationed in California in 1885 and 1886 ( Essig 1972), so the collection was probably made during that period. Although we could not verify it, the most likely station for Casey as an engineer specializing in lighthouses would be the San Francisco Bay area, probably the Presidio in San Francisco itself, or perhaps Point Reyes Station. This also may have been the assumption of Cook (1899), who, however, suggested a type locality as near Sausalito, Marin Co., California, though he did not state why he thought so, and this is hardly a firm designation of a type locality. However, Loomis (1936) listed and described additional specimens collected by Cook himself in 1928 and 1929 in localities somewhat removed from the immediate Bay Area, from Cordelia, Davenport and “ Santa Cruz Mountains ”. While the Cordelia and “ Santa Cruz Mountains ” specimens could not be located, we were able to examine the single male and female from Davenport conserved in the collection of the United States National Museum of Natural History and in order to clear up the identity of S. californica , accept Loomis’ identification of them as that species, as they conform to the descriptions of both Cook (1899) and Loomis (1936). However, Davenport is some distance south of San Francisco Bay, so we enquired of the California Academy of Sciences if they had material of striariid millipeds from the immediate region. This material was loaned to us, and while it consisted mostly of juvenile and female specimens, males attributable to S. californica from Marin Co. (near the suggested type locality) conforming to the Davenport male were present. These S. californica males gave us further confidence in our identification of both the Cook and San Francisco area collections as S. californica . Bayaria nana could be eliminated from consideration because of the great size discrepancy between the two species. At least at the Point Reyes localities, A. californica and B. nana are sympatric or even syntopic, both species appearing in at least one of the same collection vials from CAS.

Figures

FIGURES 1–5. Amplaria californica (Cook, 1899), n. comb., male from Davenport, CA.1. Front of head, anterior view. 2. Left leg 1, anterior view. 3. Postfemoral spine cluster of leg 1, anterior view. 4. Legpair 2, posterior view. 5. Coxa and prefemur 2, posterior view. Abbreviations: cx2, coxa 2; ls, lateral spine of labrum; m, mandible; pf2, prefemur 2; vd, opening of vas deferens.

FIGURES 6–8. Amplaria californica (Cook, 1899), n. comb., male from Davenport, CA. 6. Third legs and postcoxal bars, posterior view. 7. Right gonopod, lateral view. 8. Left gonopod, mesal view. Abbreviations: aac, anterior angiocoxite; cf, coxal flask of leg 3; cc, colpocoxite; cx, gonopod coxa; f, flagellocoxite; pac, poserior angiocoxite; pcb, postcoxal bars of fourth ring; pf3, Prefemur of leg 3.

FIGURES 9–13. 9, 10. Amplaria californica (Cook, 1899), n. comb., male and female from Davenport, CA. 9. Male legpair 9, anterior view. 10. Female. 11–13. Bayaria nana (Loomis), n. comb., male from Bottcher’s Gap, CA. 11. Collum and first ring, dorsal view. 12. Head, ventrofrontal view. 13. Legpair 1, ventral view. Abbreviations: cp, coxal process; cx9, coxa 9; lab, labrum; m, mandible; t9, telopodite 9.

FIGURES 18–26. Amplaria californica (Cook, 1899), n. comb., male from Davenport, CA. 18. Left gonopod, lateral view. 19. Left gonopod, mesal view. 20–26. Bayaria nana (Loomis), n. comb., gonopods. 20. Holotype of Striaria nana, right gonopod, lateral view. 21. Striaria carmela Chamberlin, 1941, holotype, mesal view. 22. From Point Reyes, CA, right gonopod, lateral view. 23. Same, mesal view. 24. From Boetticher’s Gap, right gonopod, lateral view. 25. Same, mesal view. 27. From near Petaluma, CA, right gonopod, lateral view. Abbreviations: aac, anterior angiocoxite; cc, colpocoxite; f, flagellocoxite; pac, posterior angiocoxite.