SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dcb8a65cadc895adf2739e03c6c1905d5619eec56f66fe92b697961e15eda52e' 
  AND token = '2RUAawziWzyy+UGX3IE2/DFDcoCWRcKws9XYlglLhls=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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