SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '04af8f86c0c0ca496e07ee7fd5960892576f30ed3f5ac18a8cb52e83e8ab6587' 
  AND token = 'cPo5WkcFQggZog5q1UxTfCobUBLdc07KzxhsyFfEiGg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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