SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'dc741289bf4833e55fe4c7a6c2e57bd262291ab1aa4a9f344f2e2c43996fb219' 
  AND token = 'G42LHZe3idZEKXHle9MMFYy+aXv0/9Upbzv9Ifs6mUM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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