SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '00be60cadcb4c18aeb2ff68850d0052dec11624986ee694686ff4f30bfad762b' 
  AND token = 'xbO7wi0jQumfijr9H8Nr4C5ZrQchUJJkewtOzLewIl8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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