SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f86fb3569c2c1a5480af20d3a135ac6ce804f3686c4682ba4f607963208964c9' 
  AND token = 'GexY+SQVcLSnFHF6EVX8azE10IwS1aDtPMKZc65OTtQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables