SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd31f5a29d22b1af1d42b2a5d1ed70ab057bcbb3a6ce32702cdd0ee9a01382fba' 
  AND token = 'I+PkVxghqGAWqbw2KO15oCtd4MenkkOWhm6rAxWsFDw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}