SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ca113143973c96ad464660901c7cf1ed62a35be1799975a0fcb8a1418448fc8' 
  AND token = 'qJKyQnaHC2NtUB4FzxCO3o8zVYaqwNXIOjOe6DkTAUQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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