SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '980fe6167e969f1edc4c38b68b1c32c66f91f74fda9e267cc263b502218757a8' 
  AND token = '7q2tMCa+S3UqRPsrTOn7+Q6rkPyXbQTDNEvggTVwDUk=' 
  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"
    }
  }
}