SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64906bd96888cbed067e7503a2374d0164ec6f22468463516fc2a8e0eee61765' 
  AND token = 'MFB6eTaUJEwfuiUCwYuhWdbu0g3TYLNWamkO12u8u0s=' 
  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"
    }
  }
}