SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5d2402a62f416292dad39a2767067db8a59f926e67a9833f3c1be5704b192f67' 
  AND token = 'eDG3LI3V6xz5URdCt3668lpjh17xl4UyGHI+XI2YIEs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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