SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '66203fdaa868f53d632076cabcb7639af3b18a3717b07aba1b6a9ff760dc1902' 
  AND token = 'ICiNEOktsM+vnouPVPUgU4L6erSu9oGNBukbnyvz2o0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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