SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b35b7a345282b015fae7843e0d1aa17d9c90fbaa964c74ba95a9727dfa506581' 
  AND token = 'TbYop7+JCktzXs3k2JVop1+CWuQ32rKSHCkSBHsv34A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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