SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fc974103b0be130e17ffdac230f8f0943b91abc38cc675db5804c5b4768f5b3b' 
  AND token = 'BT71Ls6CKM6+7ebHnXMZ2nJYNv2gPvQRmjJPxPIVOmg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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