SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3a854c1326184660042f033d418815015051c511cdd6d43e9787a561fe10738e' 
  AND token = 'ijfBFKQQgPbdFT6PkOmfb/ID9wuVErV7npaRzuIIRPQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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