SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bffe9767d2b1495d2a54a880cbbd067af9a690f949a56738228d3a6190ac7fd2' 
  AND token = '01W+YmMox31Pf9ve7uLQRpF/5mJBbgFVjmT1UlYYGCg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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