SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62a84cf6cdc33549195f0488c374f8d09a43eebaa96ebba2ef7dae06a72122ab' 
  AND token = 't/sLThqfwpRWs9Re0sDzPIvAlTOS4miZV+wy+nuGPuY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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