SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'abb831d1fa4eef242ae7f2eb74d6b80f5bb8486384f79cbb6b521d28bc43be73' 
  AND token = 'Ypi+7TVQAAo1XCpzgEePtqSujD29iJbG+8bl9upgoUU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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