SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3da03ed97c4b7e0993af4ad83905c324003a4dea5e53714c59e71f888978cf95' 
  AND token = 'JDKfULV9jUWkKASWwBdQbTc78pKHxTYuDWhCKq2aL0M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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