SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'af7a5d33d8f6191251f7be492253414b96a292d03839ce1c668e64a7ed852401' 
  AND token = 'lp5j6Dq1+k2SQF38sMLtlUNuCoqJMH0/8QjP2gQjXXw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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