SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1173cddceb5e19b081532d8287febd77e62669990cc884f075c4fc2527272cb6' 
  AND token = 'Byi20lrdm6SZwV9gL1UdU2n0YYlsqEV4FSDZOvQuUuo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}