SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '928189f207c7975e1d664ac2e7fcbe4e354353f94776e779ceb9776f116f4d9a' 
  AND token = '0Z5dnA7WqMVuVQ8AjMeGIM/HMrlGQcyyPrI37rx1DS4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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