SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a7d28c483ded2085eec0da9a85ff7d97d30144a59ffc64c05de0d0082ced9d2d' 
  AND token = 'ZsVakPaol/lE4qAn8B1FAupEiz5u78HchNwJB+6b5QU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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