SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf30e0bac2a91d0cefc95298ae421438126f4002fd45eda7f6955b9d994ea951' 
  AND token = '3341tGQ55aoNDYov6jiyOJGhpP2ONd4FnSvDbovYOGY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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