SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf5834b5551a7a75bb81326caf66408ea88cc569224cc8a2571312f38fd2894d' 
  AND token = 'SS9jpyvjxx/lxbfwymniTUIyE0cOtabSfpqvKdb4BqE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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