SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5b822ccfbdf53f867cb8dc36f34abe05d8908565692f6f8eb08aba6317054bc7' 
  AND token = 'cbEGCA0AB1fuVRgZTDoisFPPqPhUntrmveJ7wdqMi2k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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