SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c3ba766726096cd3eed418fb2e82e4c939033a99203e0f911bd1e61db8e2bca1' 
  AND token = 'Hg/vExvM2N+txrio7wWFqTO7OBWjqjHUHFenAXRUqhU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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