SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fe0cd1097c4874754aa7fb1dd9a7e526c94b9b8ca821428d9c1bda38220da8b6' 
  AND token = 'zGhiW+YUqCYE7Mb81pGwLzbjK3eGKwRMezVtgXfUJLE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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