SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f4af73a7814fe633a676a16b5fe5e77cfd18bdc3a0a480cd1de1673be64ddcc' 
  AND token = 'N+WNGrKeM8Bz40FCX0QHAdkSvnhjXb929rswptEdH/I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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