SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'df41dcf9ef3965f94ff85c87baf61a362ba685a9152c1d9f4488e4af3ccef1d7' 
  AND token = 'w2EfP54wi8rR5YJCqxi1xW5EppYmfBJ2I13Kxrk/8Z4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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