SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9c2445cde085cb8f7e7f7c5c152a35db093c6493dd56110181872a6d8b252740' 
  AND token = 'lk1qd/k/VVxfuCLqLutwKo0/NWT2xagw504ZXvmEDvo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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