SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '18fda4f5abdc0c6825f5543d19c1fdffa835dfeca2b4ce37bbac529e0ee1fa4e' 
  AND token = '5Abw7BkjNmdAS3F2rvkvT0rsQzmU8U2eaXgacgNEHbA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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