SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd8ab4df5e4eda9744a087e745aebbafca7fe16b75d12d9bc41bbbcb55b35fbb6' 
  AND token = 'qc5Gx5rPKSE5qz7hmQmSgOxL3dFP36Q825r/7jcBHNs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}