SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e4bd7b5226778d8358bf6dff40264cd1a8c0ae7fd3c6e2948f5ad7e1c89e1e91' 
  AND token = 'NvqtUwFsJhPXMIhScAS6W02sckojZ4y+jvOcozP1umA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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