SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e9448e701904a489aacbfc5a4daf2fc2b499c2aa51362fbc9d0664a43607f7e1' 
  AND token = 'pRfZYaxDv5EmZEXHixZuXjGYwmhCdZ4lVR5n1YwK5wc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00060

JSON explain

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