SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '207e672c4e352accd35915d30a13283a182db18d0209a262c045928e53db8e3e' 
  AND token = 'pfRtNh3ChX5ZoHzt6DQmnPRoyp3d+i7QtLhaJpo0pYY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

JSON explain

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