SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '897c65c5fa38c151ce1b4fe0d6548ab946a0db0eb9c7b449c34dfb379a807672' 
  AND token = 'ljYoKwCYVcorzXXRJjXyzGOoF7wUSnhoyppwnCBQcNM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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