SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4cc1313d6256c807c2890ebf8391d67f377bfb394df5695e4a96cc099fc850ed' 
  AND token = 'AzJK9KF5dO0E6gQCrSbRGLU93jfw9STNgnrTkOSkHzc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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