SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1810269e772446a281cd6d0d4570cd32682d1f8fbad7a079647a03d4b3aad9dc' 
  AND token = 'aUifjpcmT7YTFJ7pHJwI/w7j/nrkOj9FOrbQIKBFpjc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}