Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8f340758431410d56f7707cf6be0610e470f384df3d822424706d8bb5aa9750b' 
  AND token = '8hh4HPcQAD1xZi1Pwuehko9LZmsAwMXFwn3+IiRAhGY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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