SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3256fa984460055617d8c52b7cdd27759a40d97d358323826cf2a6cf7fc2c8f5' 
  AND token = 'KpnjtxxZxBgW0t++mB7yI7M7nnKiG7+YOUAV9C4LqyM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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