Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '761ff00b308e7ea5e84bd0091fc3ebaa9eea2a4c5e138e065ac6f18e712cb163' 
  AND token = 'OKbBnZ79hkYIPdD1a7dkolOqnZ+IvKA2+Yw1WrfriSw=' 
  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"
    }
  }
}