SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e55cdc2b4a644ebdab5765c70096cc6855a9445df236b483d83b593b7ecd441b' 
  AND token = 'Cc/mm6CApcDGsuJjrQcWdHoO+yihXuxgVjf82cJSqD8=' 
  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"
    }
  }
}