SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8fdce9b0a3276be475a3576e1b0cfbb22d647af9d7928d8adf969822d8c1f91a' 
  AND token = 'VXFSGNTgNIga7VhFVtPlEB9sjX4oB1m/XGZvxOT+fwg=' 
  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"
    }
  }
}