SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '952cfba05083d19f1a2b2ad137478a7a4185a0dfa48b5fbf9fcfe249de93968f' 
  AND token = 'mIo/8iNx7Tb30MUSbVVRP/JLP+FVzyQDhDRIdjZgdgk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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