SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'dcaad5550d75e8153660aadf2bbb0ca3375901f082451ffa4719f4d2557fffe9' 
  AND token = 'zAN0Mrz77Ub89MMmAsNr2hBCBhC6lHXESbd19FkGYMY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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