SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ed6e7b6867b7a642d9d20c12d43e959319f12449c05e7179bf99946ea528211' 
  AND token = '25giY+jJpyi+VGB+KXaLSoXyePk64AXKeAdP/Z8rdbc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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