SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'af07ba7038c47615039e30c61c5a083f9bd12eede3e61f98472fec004fc9fb7a' 
  AND token = '9s5R94b9QXuegDGv59vgrjQI5LfEAEW5UxMBbTcfmUI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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