SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25a69fa14d179a666eb894c622f618f9fa6e3796064bd62aff87e54899bc4f89' 
  AND token = 'w5e1HntfcNeJQZtMVL1GTF8TS/ar+3tqvwbr2oBYpl0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

JSON explain

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