SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3d1d7aa77be82b4633824db35d64e7ff2b064ca1c890ec4243e3eeb33950569d' 
  AND token = 'gvwSpPT8ML5a39oDX6DI2yN1K99UFRD9uQCJem2TmHc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00054

JSON explain

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