SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5dedcf817e8354cdb5de0ce25b768c2dc2d2cf4156416510c14d7752ad322c4d' 
  AND token = 'MvuNtgoakdTLpoTY59JFAPxDfLOwDbIGmDLisJRzVyg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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