SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ec5ee568706ae1fcc2276d08645fc78c9ee6e311216032e39a898e034ed8c241' 
  AND token = 'riik9J3waZv0vggRAmXt4mvxGwLFXtpHqmr+AbP8iRU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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