SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aafea8aa9a4576ff9f8e70bbd956412176874951972374955f511460a7021bd5' 
  AND token = 'EruZ6aPkgfImB9amEacX/ylR+e5oQeV2Cj9ib0TYlRE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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