SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '87e6c42712c1f5603d4778bf5132712616eab63aa0880ba0b43d2733b551e33d' 
  AND token = 'jmj5nesuZUR+BX/UAC200daKqgJYOFX0vWDYzyyC8LY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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