SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b85f96fcb23059193bff35f73a421a7bc06f0272d3b7f9ce20e5c540eebc2198' 
  AND token = 'gJcD7Zf56H8iIMMB6zbeUnRotbKkJKCzHLTGUYyhJYo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}