SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f28168f22c5798ecc11e0c5ff84fc92d438bf50304d46408ffa3fd5c4b80aab7' 
  AND token = 'W078IEyzsBJNiHUmaImmNfIvlWbUZVgboZkKlLNI1Gc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00055

JSON explain

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