SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '582760a8c368a15f6d03f48e42c6f673dab8a8b9ca2321e541849bfa74e35409' 
  AND token = 'OOdr8Cu+Vnq0KQgBcTpJPTicwkLAAq4t99aK7puZSvg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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