SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '09ae8d5edfc56f304c4d04891c093171d547faa393cb675c2eb6319c14ca1ac3' 
  AND token = 'eCxPvFGhVfqzkBl7GbQ+lUhm8XsduG2GqNN+42/j1T8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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