SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a95031189f310d998a559404477e8400f9b162915d2d8f1d680c01b67e5f6003' 
  AND token = 'OyVKfBrYKKBVuRVYCOZLyTAPKuBd+MBwPr23O/Zrpu8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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