SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c272ddcc26a2555ca996dc346a76d082f83dbbeebdba2feee7ec54738325f163' 
  AND token = '3/eXtqc9cqkJV4DuVg/Pe87h2z454wsOMmP1eFkKsgU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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