SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f8a2f8388175603744ce5e505dd584a5ddff71e685297002b29a4183e80107bd' 
  AND token = 'CxhytLSaUY1bFT0DRLChFyGj01ezxTXyqio9aEf1sBU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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