SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a22c747af60d0aa1a5df4ad33610016dc55e79c42743ea43895ff36dec061c3d' 
  AND token = 'DmXeHeTZncJULG6rbsqRQpCWk9K6lPGHXfiyAompIxE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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