SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f99f5fedbda4675c0807a806b64fc70f5f81a800bebd0db6a40c7356a0828ead' 
  AND token = '+qquH5O/msDIslH0JdAwMHtM/wzpbmG0fP39RflgwiY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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