SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd6dc4b9248a29a725783418404d4294588d0fa230808245374cbc94e82b1293b' 
  AND token = '351voQxoKYQzpQWpt0haZoIUPpropNYAfSXWOYBqGm8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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