SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '823592937425b0762095a9d13c6f7881c99e99e5c4238216b36eff5785626835' 
  AND token = '6ucAihmch8y4xmxnegtRtpLr8BGEo29DPo69LpLcF+E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}