SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd1b4fc949bbfa5843c72c67ba92533e31516c13cfc7b53029ca8e37f5512e8ad' 
  AND token = 'Bz+3oiWmZe3TPjjontYeh7Rm4SHZVf5ohMtOx1wkcHc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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