SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1da7a399e5e196d105bfc2f40e013e8700ad3091fd1db3bae8b0e398a87122d2' 
  AND token = 'SYGNLnfN5YtjEgnYpiVuDn2eeF297Pt7m7J+AJsLn20=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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