SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '956d4e4b238230d876d0ed2fff9fcf46c07145bcf1b6eec3c58fc3c4c7cbb421' 
  AND token = 'TkGsLTVwZoQOCjWAz1Je5dZmYWwzG+/B7cXKg/ImaFc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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