SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa7a86b123d6ab85203b1258866536baeedbc10517af7aee0f9e1f5c5c5a393b' 
  AND token = 'FLl7YfgRTrEvOQ6BDFHGlh2FJMQnEYNREynrtz5hnXI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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