SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa3222e50551be501696521e8c31bb72ce5bd26d729df82c70fb9ad7c8c295b1' 
  AND token = 'OMPeMN1wbiSPrUsn3bMpcf0TCEmHtJI03PwYRJTJhmc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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