SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3cb5f2694b924cce0687918556787f90703041a2f6a815ceccc559c9f5d1f07a' 
  AND token = 'NOL26yIRLeKK6I6y321RF+Sj3CZgnj8U/0kxAwGkkDs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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