SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d04324ea194d5afd58c36997bac754b13714021f533238f0bb6dd26f6d09df5' 
  AND token = 'Bkd+ra3miEGJVaqYxK50cFgcSTFT8aaFLRSmiWpwYHo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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