SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9940c7f95f239d3453b2cb5a113ee02980b3941818b5cce16215284006ee32cf' 
  AND token = 'bZGUpxBJqmfqxLEo5+FR/q3zdJBHX7TScUa/DchEp0Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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