SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ec4f1be36b3f1ddf7e5849436af6581e3636b8106632ef9bd881ac812580331a' 
  AND token = 'Pm6t5WWUoKQCZSeR95vw4bPtzPUje133jak1khIizUE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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