SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '585571398151f546a13d0b0a1432d0c95ce2bb6679386e6d7cd06a5669f5143f' 
  AND token = 'mi/yKWpkVPDehrhACVEhYFeJ6fYozpg+Ti8x+S/XxTk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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