SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9da90dfe640efed9ee8d1c782de87693fb56601ded103222403281af2d39783d' 
  AND token = 'MypHm96/dUZ9vrnh2wds1oWYbukZZ3vTJSeEvkMqJZM=' 
  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"
    }
  }
}