SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6edde81806228d409ea22c23b0c0e4bca6667b97f917ed5cda1c55756d6aed24' 
  AND token = 'a/8nwVP/W9uHdZHrRfnIITxqBY0XFPClV6XfLicsOLU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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