SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7b110c7afa5d6261827714685b413bef7d1b668a35ba501767709c5b71b17913' 
  AND token = '/tDKZTukWFCo+azxVnFK/ZjUz3OS8+spwjOjvHZ8wUY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00074

JSON explain

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