SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd33bdaaaf13596c1f7ec4dc28776e2aa35318fdb6c926c28674056f391b16808' 
  AND token = 's0aKoJr73AWmr3iYoXCMHpIoHSlGdSUG9U2EKAZabb0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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