SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cae315f7e48842828db39cabba24318336ccdbbd58b1a182f1fb5e4cd75b5569' 
  AND token = 'JX7gZ4rQJbAxzixPTpOaNCAsTBMATDHDBVPbbDDSAvw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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