SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9ef8d0154d7cc0d29939f67c566327e17e3b13968f2083291453ab67d1b9cc4a' 
  AND token = 'dZ2/6sK1jUHnXX2KWw8YDxELUazD5AQLkSRTT4Xbrsg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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