SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eba584a32be10ebe46eb7517adc1ca05f26fd72e904baf897e2830266ea09621' 
  AND token = 'DkWg3S12fSXgk3XuHD9X/K4vwcTdFNqcalXO2kto8gQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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