SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd89fdc52f45efbdd614c489fcbc5757ad2f5765b9269219a0a499d8a0a386c5' 
  AND token = 'qRbns2wxJYqVkYlsW+o41oPXLMk02+z3qpuQuEFgZhU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00072

JSON explain

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