SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f0afc2c9ba4d21a447e379f1c85bd2419a5874f902641f16f246fdc5c38a37e' 
  AND token = 'RU/oKpJqgom9Cubk9khtVLi8ygYQ6TAlPv6W7pZVhrs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00065

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}