SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9cdad5d09867b7db368aeaaba7a98074e402ccd1ab1d282da17b2e5501f92202' 
  AND token = 'E0LooEHStxvneEA6okfBQxpyCjF4mGBnZtib8YLuDj4=' 
  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"
    }
  }
}