SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63140b7ea81ede3fba145c9559a6a0fd6707fc7ab551015601765c20ff97a08e' 
  AND token = 'SnWxhSiZqdz8KnEOih6FnWUCyw4pJqasOYkz8YPw+7M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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