SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cf96a98df8a25934fe6af6b4dd72d12a4aa3f38272a07fa9a524b9a7506bfde1' 
  AND token = 'JvGRVLu0CtHgMj7EFDyQFDi5xBFwe39iMngj303K64o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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