SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f16633585cc497d8513eefc80f4421e092e16d125234cc37985189d69d5b974f' 
  AND token = 'NlLEp1xk3ixgZqzVGbrKJGUJH4cqaBscU8fgwy6ldRM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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