SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f3c88e2b2fefe1f490b2e3daf43d32d8c246843237178c20a8e7cf51aabe3107' 
  AND token = '/dzE7GiVzH1eXFlhtP2Xkb9Z+I8fSNDh+bGA+LMXwt0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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