SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8ad00e10fef0e33a3a1cb9c508347f27f2768e1c68128b56b7a8a19d84e5d57f' 
  AND token = 'RdM2hBaj8R6ZdhdYaWSB934QEGqnCTuykzDv6ttj2Zg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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