SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '46c6ea8387e89819a7167a42ebb1a21d9cf9d81b8222de9898cc1be1cc61b969' 
  AND token = 'uOE03HMINE36bxlNvETCT9SIMAePYq9l74II1qyUyfg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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