SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e743c56dc8fd38bb6c61862d44ac5d5843f529779f6fef7eb7cc552e59df7d54' 
  AND token = 'B1JV7+0A9ZlejPjhqZ+R+pFzA6DXzn8+xlcmwRx6vuU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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