SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b86af8ef90f989017bdb6cb5c0402598135d581058373ceb25b406b7010b3390' 
  AND token = 'PwPSXw3ttZ7tdgvyeuEolQFY8mwsHZsDqOa7ZQtgnhs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00065

JSON explain

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