SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'daa32cccca126427ff9bc57fb65c5f57289683dfb182e0e4e99e5993d388cd38' 
  AND token = 'CPx7HKKgj7AUdJCIalM3zQByZ1vVEoHWf5MG+9KxJdw=' 
  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"
    }
  }
}