SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4f0ec8a0b4d242833b22bcd766def8211f5b8e310b6c325c7617b8b408a28f29' 
  AND token = 'jvH4qm0JdfxWV03O72B9S27hvwCv/6BiGCeiu6M8QXc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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