SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '093ddbb73df2e6b50e0d8aa62a0fee14ccaea6246d1fd89df34edf88cf64a861' 
  AND token = 'MUKmo+D8J2FexRZnasMLcTLXDDXZwtJrtm2FiFIImJI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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