SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '95533292e50be708dc5d19c495ed650839bcc43bed94d1b585192a64c802f637' 
  AND token = 'y8Ysp/Y8dHvGglJxUrlUxQmnxMAOJwqOVgji9KzWDHU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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