SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3e1c0d2fbf821ed0b1eb21229526f8dfab314b300b601cbd55baa125be75cdd9' 
  AND token = 'TP1AbGO/UkrbKoq9ylfmvr+346Kch+kSzF8YBLGPq0Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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