Pseudosinella intermixta (Folsom, 1924)

Katz, Aron D., Taylor, Steven J., Soto-Adames, Felipe N., Addison, Aaron, Hoese, Geoffrey B., Sutton, Michael R. & Toulkeridis, Theofilos, 2016, New records and new species of springtails (Collembola: Entomobryidae, Paronellidae) from lava tubes of the Galapagos Islands (Ecuador), Subterranean Biology 17, pp. 77-120: 90

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Pseudosinella intermixta (Folsom, 1924)


Taxon classification Animalia Collembola Entomobryidae

Pseudosinella intermixta (Folsom, 1924)   Fig. 13

Descriptive notes of type specimen.

Slide mounted syntype is 0.63 mm in length (Fig. 13A). Unguis with 3 inner teeth: 2 minute basal paired teeth and 1 large unpaired distal tooth (Fig. 13B). Dorsal head Mc A0, A2, A3, and M2 (S) present; Pa5 absent. Th. II with 1 Mc. Th. III without Mc.


Pseudosinella intermixta   , originally described by Folsom (1924) from material collected on Baltra Island (as South Seymore Island), is the only member of the genus with 3+3 eyes, an apical Ant. IV bulb, with head Mc M2, 1 Mc on Th. II, and without Mc on Th. III. Folsom’s species is very similar to Pseudosinella stewartpecki   sp. n. described below, but can be separated by the presence in Pseudosinella inermixta   of head Mc M2 and an enlarged unpaired ungual tooth that is larger than both inner paired teeth.

Folsom’s (1924) description of Pseudosinella intermixta   is relatively incomplete, lacking details for many important characters, thus it was necessary to revisit the type material to determine if our specimens (described below as Pseudosinella stewartpecki   sp. n.) differed from Pseudosinella intermixta   . The syntypes, stored in ethanol with labels (Fig. 13C, D), were in extremely poor condition. Despite their poor condition, after slide mounting the most complete specimen (Fig. 13A) we were able to supplement Folsom’s (1924) description with the few additional characters provided above.

Folsom (1924) described and illustrated Pseudosinella intermixta   with only 2 subequal inner teeth on the unguis. However, the mounted syntype clearly has 3 inner teeth: 2 minute paired teeth and 1 large unpaired distal tooth (Fig. 13B). Due to old age and poor preservation, dorsal chaetotaxy is mostly obscured on the mounted type specimen, but the head clearly carries Mc M2.


Baltra Island, Galápagos, Ecuador ( Folsom 1924).

Material examined.

Syntypes, 1 on slide, 5 in vial, Ecuador, Galápagos, Baltra (South Seymour) Island, Apr. 22, 1923, coll. W. Beebe, 2296, dry restored with NaCl sol.; INHS Acc. 567,409 (slide mounted syntype) & 567,410 (syntypes in alcohol).