SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f979de321b2a8fe345212bd28c239538db9920197a537dd08d328a3aeee5493d' 
  AND token = 'rag1BkG0kW+FhlC63DV5PBP+wSN8IbEkphG+KXd6DNw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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