SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '85ffd75498fb8ad1ba7e9d0d5f315479ae6b5d5162cffb9f5a13592b3ca2a2be' 
  AND token = 'ObDp6ggwns1VSz/r3xxZPquvbr4ksbPr8wqKdH07T/Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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