SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd7cb7cbe29ff1c6e8c4165fdd1387ad5fa64f0a9966ce688f127619226f59f9c' 
  AND token = 'jE/SBh7V4GAwVDvlYcYTTgL81qQKgiDOjCvSTaoWm84=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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