SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4080ac602f387aab3fdf67bc31d4f5c5d04ade1e884c3fdbe0aef4bf3280825e' 
  AND token = '1C3RHw/Rrv8LEMH9+5ALRk7rnmsZ/6IVC5A163YPuTE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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