SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1192bf05142509ff77ff4d8a588afb1e2bf73bff32bc28d2698394ddec2bf05c' 
  AND token = 'jn3XoohRD6KCQfT47ZlRh6RLk6gIdWs5aalTB1TVr/E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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