SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f361b1a2882c20421b7c2f51b28e3862ec7d37be77bff6da467aeeb6a8f631f7' 
  AND token = 'xNPZnOuMiaOIOdmUiLDD9wzB9LwNA9em8coZnEOkj9M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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