SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f495c5d19a645c55b52f02bacfa3588b5cd82f75e2713c59ef62173011b8440d' 
  AND token = '9/HpaVocPvhTCrz6jSV6utDP3vQGihOXF322qDspcZw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}