SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c9a2b50b8f524b688b5fa68629e04e62fc331ec47931da952122a730f5ba342e' 
  AND token = 'BiHErHpoIDF7oEhKhYBmqgKwu2/EMpBC0AohEmPGbDo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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