SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd998c3a42818ce5e8b0b58d622bfb71eaca2e0a1403458ab86dc6b20dc094cff' 
  AND token = '3qfKrVLOKYoVPPk/qsLwXe86ahNVxEF618FmQWPSjKQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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