SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '14978caf99eb271d7cdd42680ba5e580e48d15f75ac0a52dc0bb94b732fbc75d' 
  AND token = 'mJFcbW4Km0YKH9zFWZnB+jgZaHW8gnWBiDK0M7pvF+Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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