SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ac0c880979c1a6768c12f960ba4e000ecad935b6e83311a57c797873ae95bd3' 
  AND token = 'i8A8A2dIjb+pHNmy9D/ZDhyJTwxULKEujoqiVBq5TGY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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