SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60b4ecabeb7af77ef39092865fe5ff3a62da84e072b2398fa3aa3d68142e915d' 
  AND token = 'sgyklGIR7rpmQ4hh7OWvyjFNoL24bJ7KFrLV+BpjJvc=' 
  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"
    }
  }
}