SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e12ea825313cc320d5d94a7f64aa8b58758cbb9cdebeffc48ae2ee6e060b624b' 
  AND token = 'eybVnYwfQYklPG1IsEQfJKkF2NUmtaRoiErx1tNlcaU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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