SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b0cbe3ec8b00bb75fb4cbb0d4d22c68ff538a5d07e639136b204911a67e973ff' 
  AND token = 'swzqrIMPJp3IkG2m8OcQwHQ5YW/Iw6iiE+TEXXmRIMg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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