SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'aa6cc41ccf0450d390bfadb4ab720ce63e693138222864a4db4728944cc89ca2' 
  AND token = '8dgbU6InBn5w5o0Bs2xcgxQ1Njs1bKakBZJ7h98NoPs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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