Bellisotoma joycei (Soto-Adames & Giordano), 2011

Soto-Adames, Felipe N., Giordano, Rosanna & Christiansen, Kenneth, 2013, Bellisotoma, a new genus of Isotomidae from North America (Hexapoda, Collembola), ZooKeys 283, pp. 7-13 : 9-10

Bellisotoma joycei (Soto-Adames & Giordano), 2011 comb. n.

Material examined.

Holotype (Illinois Natural History Survey [INHS] Insect Collection accession number 551,608) and 3 paratypes (INHS Insect Collection accession numbers 551, 610; 551,611; 551, 621): USA,Vermont, Grand Isle Co., South Hero, White’s Beach, N44.62189, W73.32273, sand and thick layer of aquatic plant debris, October 2005. 2 paratypes (INHS Insect Collection accession numbers 551,609 and 551,612): Vermont, Grand Isle Co., Grand Isle, Pearl Bay, west of intersection of East Shore North Rd. and Hide Point West Rd., N44.73078 W73.26401, sand with sparse remains of aquatic plant debris, October 2005. CANADA, Quebec, 9115 (1994), St. Jude, sugar maple leaf litter near N45.78333, W72.93334, Berlese MO-SJ-2, identified as Proisotoma (Ballistura) ewingi on the label (this slide contains 7 specimens and is deposited in the A.J. Cook Arthropod Research Collection at Michigan State University).

Remarks.

The specimens from Quebec were originally identified as Ballistura ewingi , but in the key character that separate Ballistura joycei from Ballistura ewingi (number of distal setae on the collophore) they are identical to Ballistura joycei . All specimens from Quebec are small, the largest measuring only 0.78 mm. Two of the seven individuals from Canada are males. In the largest male the genital plate is well developed, but it appears to be closed, and neither males has modified metatibiotarsal setae. These males are either subadults of adults in reproductive quiescence.

In the specimens from Vermont the number and size of eyes varies, and one individual is blind (Soto-Adames and Giordano, 2011). In the individuals from Quebec the number of eyes is constant, except for one specimen in which eye G is missing on one side of the head. Dorsal views of the prelabral region suggest the presence of 4 prelabral setae (Fig. 6), but a lateral view of the head (Fig. 5) clearly shows that the outer setae are displaced posteriorly, away from the labral suture, and are not prelabral in the usual sense. One individual from Quebec has only one prelabral seta. The number of microsensilla is somewhat variable. Most individuals have 10//10100 microsensilla, but one specimen from Vermont has one microsensillum on the metathorax, and the two males from Quebec have 2 microsensilla on the first abdominal segment.

The shape of the tenent hairs is difficult to ascertain in the specimens from Canada. In the two smallest individuals (0.69 mm) all tenent hairs seem acuminate, whereas in the larger specimens there are 111 capitate and 011 acuminate tenent hairs. Most individuals have 3 tenacular teeth, but two have 3+4 and one has 2+3.