SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '93cc43ce7d5b581a6130cf10e9a1180ad7fcf78ca7672d19d32410f5e45f0b4e' 
  AND token = 'iMv4o0RgZbLukiQszQRzRASjxGWl1FK8FR0ozcT4eGU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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