SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '824e64a780a635a160a14e5254db882127534bba7634b07a28afd9a9c65b9785' 
  AND token = 'Y/qpTLKs3YuF14hlS3Xw+Qjpq6M2FkxsBcv40j5/iKs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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