SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05053d2e1bb64183e55a47470ddfe5e33f8571a9a1d3d7b97d70b734884ff1b2' 
  AND token = 'ZfYgdtPjhRwmWl11veoN2Qz1qatE7ztcVJ9AECJarLs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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