Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e704f9f6e4b69ce18ccd4e60f4c68ca4ec1d51210e3dab7a4664237e0b1513aa' 
  AND token = 'nLBHdAyuiMumHta/mfrIE2eFxFXHdn1gTipQQA+u3bk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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