SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cf3e3852530ba6a1c084223821d1e91aab168ea21c7f4fd5385f402272394964' 
  AND token = 'dpbcOjbOM8iqJ5OhA0zWRGr/4KavDnxw0HgTgMcruCA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}