SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b1ee8f38a859eef5663459bcedb505fb1d5475381047f3db26633a9d8619deb2' 
  AND token = 'IFKIXnHP4hso/UUgY89iAYmvplrhJjPDK/EIRJt5DuA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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