SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fcb9886fcef78c78c71664554cd22bdca3e7d2f86c3234b0428c4545b8f5c9e5' 
  AND token = 'mBfGl5RuubEJcAosKHCZ/PQlfqS6V/IC1wsC02NHgUg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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