SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f322270675c282b40e0fd377fafca61cb02d8e550c52ab1c32f43bedd64069a1' 
  AND token = 'wiylVoJsez7FxLVFuWRVvdq2z7oJmk+xfJEh5Zp6gKo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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