SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f33fc5c740fc3b1d34c2f40ba30965c104308e5186babf055e16d73ffa31810f' 
  AND token = 'Z9GB04bVTnXDw0qnRlerylq/tGi8vY0VabJPQB1at2I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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