SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e6625b5d08c9b91028093c7a408fd8897c6eec53c99869aac6b4f795b1d2662a' 
  AND token = 'rznPTTUSOXsp+sG3wJpBC8+GYYkV9EE4rw97+FjzMWw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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