SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd27c9256388837da719e867f5b221f90a340e8c68aa5c1c24164bd5902b2efe' 
  AND token = 'GnPEkb6H0aQYI3WPgMSNUvQ3sEbbtlPls/Rq9dXNI8c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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