SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c9cd459f35726a930bb9c2c288f5a341fd0fa974280c47b96c7b5dc4eba3ef80' 
  AND token = 'jGvYI6+jEvYwnH8y00myjd4RwqtVto/q0NxOhLWYGDk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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