SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '63cb4386cc094018f5e65239e596be74109e48cdd4984b25e8b02e8af417f326' 
  AND token = 'WeE/Mlc9EIHPEiJQQmcsqdvMvm/6T7ar2lCebwLHzQU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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